CN113555958B

CN113555958B - Intelligent power server and power protection measurement and control system

Info

Publication number: CN113555958B
Application number: CN202010335119.XA
Authority: CN
Inventors: 李平
Original assignee: Kyland Technology Co Ltd
Current assignee: Kyland Technology Co Ltd
Priority date: 2020-04-24
Filing date: 2020-04-24
Publication date: 2024-04-09
Anticipated expiration: 2040-04-24
Also published as: CN113555958A

Abstract

The embodiment of the invention discloses an intelligent power server and a power protection measurement and control system. The intelligent power server comprises a total station multi-interval comprehensive measurement and control module and a plurality of protection modules; the total station multi-interval comprehensive measurement and control module measures and controls primary equipment of all the accessed intelligent local units; the protection module is connected with the intelligent local units in a one-to-one correspondence manner through the optical ports, and fixed-value virtual terminals of the protection module are connected with fixed-value virtual terminals of the intelligent local units connected with the protection module; the protection module protects primary equipment of the intelligent local unit connected with the protection module, and realizes fixed value management of the protection module and the intelligent local unit connected with the protection module; the fixed value database and the fixed value data set of the intelligent power server respectively comprise fixed value data sets of all intelligent local units. The intelligent power server realizes the unified management of the whole station, the intelligent local unit does not need to be connected to equipment except the intelligent power server, communication links are reduced, hardware expenditure is reduced, and reliability and convenience are improved.

Description

Intelligent power server and power protection measurement and control system

Technical Field

The embodiment of the invention relates to the field of protection measurement and control of substations and distribution stations, in particular to an intelligent power server and a power protection measurement and control system.

Background

With the gradual development of construction work of a digital transformer substation and a smart grid, devices of all levels of a power system are increasingly digitized and intelligentized. After going through the course of the development of automation of the transformer substation from centralization to decentralization, the intelligent equipment of the transformer substation is again centralized to a new level from decentralization along with the progress of IT and communication technology. According to different application requirements of the transformer substation, a new generation of centralized multifunctional intelligent equipment and a centralized digital transformer substation play an important role in the process of power grid digital.

Along with the continuous popularization and the deep penetration of IEC61850 standard, the design idea of centralized protection is proposed, and a centralized protection measurement and control device is designed and developed immediately. However, the centralized protection device does not adopt the improved new protection principle, but only realizes the protection and control functions of the whole station and the requirement of digitalization.

The protection fixed value management is an important component of the protection function, and the correct fixed value management is a precondition for realizing correct protection of the transformer substation and the power distribution station. The inventor finds that in the process of implementing the invention, the fixed value management of the intelligent on-site unit in the centralized protection measurement and control system needs to be operated on site if an HMI (Human Machine Interface, human-machine interface) mode and a maintenance software mode are adopted, which brings great inconvenience to the later maintenance; if a background or a signal-protection sub-station mode is adopted, a station control layer network port of the intelligent local unit is connected to a signal-protection sub-station module of a background or a transformer station server (or a power distribution station server) through a network cable, and at least one intelligent local unit is required to be installed at each interval, so that a plurality of network cable connections are required, the increase of hardware expenditure and communication fault points is brought, and the inconvenience is brought to the fixed value management of the intelligent local unit.

Disclosure of Invention

The embodiment of the invention provides an intelligent power server and a power protection measurement and control system, which are used for realizing unified management of a whole station, reducing the cost of software and hardware, reducing communication paths and improving reliability and convenience.

In a first aspect, an embodiment of the present invention provides an intelligent power server applied to an intelligent substation or a protection control system of a power distribution station, including: a total station multi-interval comprehensive measurement and control module and a plurality of protection modules, wherein,

the total station multi-interval comprehensive measurement and control module is used for measuring and controlling all primary equipment connected with the intelligent local units accessed by the intelligent power server;

the protection module is connected with at least one intelligent local unit through at least one optical port on the intelligent power server, and a fixed value virtual terminal of the protection module is connected with a fixed value virtual terminal of the intelligent local unit connected with the protection module, wherein each optical port is used for being independently connected with one intelligent local unit, and each intelligent local unit is independently connected with one optical port; the protection module is used for protecting primary equipment connected with the intelligent local unit, managing protection fixed values of the protection module and managing the protection fixed values of the intelligent local unit connected with the protection module;

Wherein, the fixed value database of the intelligent power server and the ICD (Intelligent Electronic Device Capability Description, intelligent power device capability description) fixed value data set of the intelligent power server respectively comprise ICD fixed value data sets of intelligent local units connected with the protection modules.

In a second aspect, an embodiment of the present invention further provides a power protection measurement and control system, where the system includes: the intelligent power server of any embodiment of the present invention, and a plurality of intelligent in-place units accessing the intelligent power server;

the intelligent on-site unit has an intelligent unit combining function and an on-site protection function; the intelligent local unit executes the intelligent unit function and locks the local protection function when the intelligent local unit is communicated with the protection module of the intelligent power server normally; and when the intelligent on-site unit is in communication failure with the protection module of the intelligent power server, executing the intelligent unit function and starting the on-site protection function.

In the technical scheme provided by the embodiment of the invention, the intelligent power server is used for completing the protection, measurement and control and fixed value (fixed value of the intelligent power server and fixed value of each intelligent local unit) management of the whole station, the intelligent local units do not need to be connected to equipment except the intelligent power server, the unified management of the whole station is realized, the intelligent local units do not need to be connected to equipment except the intelligent power server, the communication link is reduced, the hardware cost is reduced, and the reliability and convenience are improved. In addition, the fixed value database of the intelligent power server and the ICD fixed value data set of the intelligent power server respectively comprise the ICD fixed value data set of the intelligent local unit connected with each protection module, the background modifies the fixed value of one protection module to only influence the function of the protection module, the functions of other protection modules are not influenced, and the background modifies the fixed value of one intelligent local unit to only influence the functions of the protection module connected with the intelligent local unit and not influence the functions of other intelligent local units.

Drawings

Fig. 1 is a schematic structural diagram of an intelligent power server applied to an intelligent substation or substation protection control system according to a first embodiment of the present invention;

FIG. 2 is a flowchart of a method for implementing a small current grounding line selection function by using the total station multi-interval integrated measurement and control module in the second embodiment of the invention;

FIG. 3 is a schematic structural diagram of an electric power protection measurement and control system according to a third embodiment of the present invention;

fig. 4 is a schematic hardware structure of an intelligent in-situ unit in accordance with the third embodiment of the present invention.

Detailed Description

Embodiments of the present invention will be described in further detail below with reference to the drawings and examples. It should be understood that the particular embodiments described herein are illustrative only and are not limiting of embodiments of the invention. It should be further noted that, for convenience of description, only some, but not all of the structures related to the embodiments of the present invention are shown in the drawings.

Before discussing exemplary embodiments in more detail, it should be mentioned that some exemplary embodiments are described as processes or methods depicted as flowcharts. Although a flowchart depicts operations (or steps) as a sequential process, many of the operations can be performed in parallel, concurrently, or at the same time. Furthermore, the order of the operations may be rearranged. The process may be terminated when its operations are completed, but may have additional steps not included in the figures. The processes may correspond to methods, functions, procedures, subroutines, and the like.

The main inventive concept of the embodiments of the present invention will be briefly described for easy understanding.

In the invention, the intelligent power server is used for protecting, measuring and controlling the total station and managing the fixed value (comprising the fixed value management of the intelligent power server and the fixed value management of each intelligent local unit). The intelligent power server can be a transformer station server or a power distribution station server; the intelligent local unit is an integrated device of the merging unit and the intelligent terminal, and bears the function of each interval GOOSE (Generic Object-Oriented Substation Event, general Object-oriented substation event)/SV (Sampled Value) to be collected and sent to the intelligent power server in situ, executes a GOOSE tripping and closing command from the intelligent power server, bears the function of local backup protection, and particularly enables the local protection function when a protection module of the intelligent power server connected with the intelligent local unit fails.

Example 1

Fig. 1 is a schematic structural diagram of an intelligent power server applied to a protection control system of an intelligent substation or a distribution substation according to a first embodiment of the present invention, where the embodiment may be applicable to a case of managing protection fixed values of an intelligent local unit in the intelligent substation or the distribution substation, and an exemplary fixed value management function of the intelligent local unit may include: checking a fixed value, modifying the fixed value, checking the fixed value, communicating the fixed value, storing the fixed value and the like. Specifically, as shown in fig. 1, the intelligent power server 1 mainly includes: the system comprises a total station multi-interval comprehensive measurement and control module 110 and a plurality of protection modules 120. Wherein,

The total station multi-interval comprehensive measurement and control module 110 is used for measuring and controlling all primary equipment connected with the intelligent local unit accessed by the intelligent power server;

the fixed value database of the intelligent power server and the ICD fixed value data set of the intelligent power server respectively comprise ICD fixed value data sets of intelligent local units connected with the protection modules.

In this embodiment, the measurement and control functions of each interval may be configured according to a unified standard, so that all the measurement and control functions of each interval are integrated into one module, that is, the total station multi-interval comprehensive measurement and control module can implement measurement and control of all the primary devices connected to the intelligent local unit accessed by the intelligent power server.

The total station multi-interval comprehensive measurement and control module can receive GOOSE messages and SV messages sent by all intelligent local units and can send GOOSE remote control outlet messages to all intelligent local units. Specifically, the total station multi-interval comprehensive measurement and control module can perform telemetry calculation on the received SV message; remote signaling discrimination can be carried out on the received GOOSE message; after receiving remote control command of SCADA (Supervisory Control And Data Acquisition Acquisition, data acquisition and monitoring control system) background to a certain interval and associating five-prevention and synchronization equivalent locking conditions, sending GOOSE message (including control opening and control closing) containing remote control command to switch or knife switch of corresponding interval. Compared with the technical scheme of respectively configuring the measurement and control module for each interval, the advantage of arranging the total-station multi-interval comprehensive measurement and control module is that the convenience of measuring and controlling all intervals is improved.

Specifically, the intelligent on-site units and the intelligent power server adopt a peer-to-peer direct connection mode, taking n (n > 2) intelligent on-site units and m (m > 2) protection modules as examples, the n intelligent on-site units are connected to n optical ports of the intelligent power server, and data of the n optical ports are shared by the m protection modules and 1 measurement and control module (namely, a total station multi-interval comprehensive measurement and control module) of the intelligent power server. Any one of the protection modules uses data of one or more (less than n) optical ports, and the total station multi-interval comprehensive measurement and control module uses data of all (n) optical ports.

The protection module may be divided into a single-interval protection module and a multi-interval protection module. The single-gap protection module is, for example, a line protection module, a used variable protection module, a capacitor protection module, a reactor protection module, and the like, and is connected with an intelligent local unit through an optical port on the intelligent power server, as shown in fig. 1, the protection module 121 is a single-gap protection module, and is connected with an intelligent local unit through an optical port, that is, the protection module 121 (single-gap protection module) uses data of only one optical port; the multi-interval protection module is, for example, a main transformer protection module, a bus protection module, a spare power automatic switching protection module, etc., and is connected with a plurality of intelligent local units through a plurality of optical ports on the intelligent power server, as shown in fig. 1, the protection module 122 is a multi-interval protection module, which is connected with three intelligent local units through three optical ports (in fig. 1, three optical ports are connected with the multi-interval protection module for example), that is, the protection module 122 (multi-interval protection module) uses data of 3 optical ports.

For a single-interval protection module, a fixed value virtual terminal is connected with a fixed value virtual terminal of an intelligent local unit connected with the fixed value virtual terminal.

Specifically, the fixed value transmitting virtual terminal of the single-interval protection module is connected with the fixed value receiving virtual terminal of the intelligent local unit connected with the fixed value transmitting virtual terminal of the single-interval protection module, and the fixed value receiving virtual terminal of the single-interval protection module is connected with the fixed value transmitting virtual terminal of the intelligent local unit connected with the fixed value receiving virtual terminal of the single-interval protection module.

For the multi-interval protection module, the fixed value virtual terminal is connected with the fixed value virtual terminals of a plurality of intelligent local units connected with the fixed value virtual terminals.

Specifically, the fixed value sending virtual terminals of the multi-interval protection module are respectively connected with the fixed value receiving virtual terminals of the plurality of intelligent local units connected with the fixed value sending virtual terminals, and the fixed value receiving virtual terminals of the multi-interval protection module are respectively connected with the fixed value sending virtual terminals of the plurality of intelligent local units connected with the fixed value receiving virtual terminals.

It is worth noting that each optical port of the intelligent power server is used for individually accessing one intelligent local unit, and the situation that a plurality of intelligent local units access one optical port does not exist. That is, an intelligent in-situ unit is connected to an optical port of the intelligent power server through a light, and the intelligent in-situ unit is in one-to-one correspondence with the optical port of the intelligent power server.

It should be noted that the number of the intelligent local units in this embodiment is not fixed, and is specifically related to the type and number of the protection modules included in the intelligent power server.

Illustratively, the fixed values of the intelligent local unit in the embodiment may be a control word fixed value, an overcurrent fixed value, a delay fixed value, a soft pressing plate fixed value, and the like. Through setting reasonable fixed values to the intelligent power server protection module and the intelligent on-site unit, the rapidity, the selectivity, the sensitivity and the reliability of each interval protection of the transformer substation can be realized. It should be noted that, in the intelligent power server according to this embodiment, a plurality of fixed values may be set in each protection module and the intelligent local unit.

Illustratively, the fixed-value virtual terminal mentioned in this embodiment is a GOOSE fixed-value virtual terminal, where the GOOSE fixed-value transceiver virtual terminal includes: GOOSE constant value transmitting virtual terminal and GOOSE constant value receiving virtual terminal.

And the single-interval protection module is in communication connection with an intelligent local unit through a GOOSE fixed value transceiving virtual terminal. Specifically, the fixed value transmitting virtual terminal of the single-interval protection module is connected with the fixed value receiving virtual terminal of the intelligent local unit connected with the fixed value transmitting virtual terminal of the single-interval protection module, and the fixed value receiving virtual terminal of the single-interval protection module is connected with the fixed value transmitting virtual terminal of the intelligent local unit connected with the fixed value receiving virtual terminal of the single-interval protection module.

And the multi-interval protection module is in communication connection with a plurality of intelligent local units through GOOSE fixed value transceiving virtual terminals. Specifically, the fixed value sending virtual terminals of the multi-interval protection module are respectively connected with the fixed value receiving virtual terminals of the plurality of intelligent local units connected with the fixed value sending virtual terminals, and the fixed value receiving virtual terminals of the multi-interval protection module are respectively connected with the fixed value sending virtual terminals of the plurality of intelligent local units connected with the fixed value receiving virtual terminals. For example, a multi-compartment intelligent power server may be communicatively coupled to 16 or 32 intelligent in-situ units via GOOSE-valued transceiving virtual terminals.

Typically, the ICD file of the intelligent power server is composed of a plurality of functional modules, and the functional modules include different protection modules and a total station multi-interval comprehensive measurement and control module. The protection modules can be a main transformer protection module, a line protection module, a used transformer (grounding transformer) protection module, a capacitor protection module, a reactor protection module, a spare power automatic switching module and the like, and each protection module comprises data sets such as telemetry, remote signaling, remote control, equipment parameters, fixed values, SV receiving, GOOSE sending and the like, wherein ICD fixed value data sets of different protection modules can be distinguished through module numbers in a short address of the ICD fixed value data set. Therefore, the ICD file of the intelligent power server has the advantages of unified configuration of the whole station and good expansibility, and for an ICD fixed value data set, modifying the fixed value of a certain function module from the background only affects the protection function of the module, and the functions of other protection modules are not affected.

The intelligent power server accesses the SV and GOOSE data of each interval in a point-to-point mode, and the specific access mode is that after the ICD file of the intelligent power server and the ICD file of each interval intelligent local unit are imported in an SCD (Substation Configuration Description ) file, the connection relation of the SV/GOOSE virtual terminal is established, then the CID (Configured IED Description, intelligent electronic equipment example configuration) file is respectively exported and downloaded to the intelligent power server and the intelligent local unit of each interval.

In this embodiment, the fixed value database of the intelligent power server and the ICD fixed value data set of the intelligent power server respectively include ICD fixed value data sets of the intelligent in-situ unit connected to each protection module. Specifically, the fixed value data set of the intelligent local unit is added to the back of the fixed value data set of the corresponding protection module of the intelligent power server, and is added to the fixed value database of the intelligent power server local protection. The ICD constant value data set of the protection module is stored in an ICD file, and the constant value database of the intelligent power server is a Flash constant value database locally protected by the intelligent power server.

For the single-interval protection module, the ICD constant value data set of the intelligent local unit connected with the single-interval protection module can be added into the constant value data set of the single-interval protection module; for the multi-interval protection module, ICD fixed value data sets of each intelligent local unit connected with the multi-interval protection module can be added into the fixed value data sets of the multi-interval protection module after being combined.

Specifically, for a single-gap protection module, for example, a line protection module, a used variable protection module, a capacitor protection module, a reactor protection module, and the like, since each single-gap protection module is connected to one intelligent local unit through only one optical fiber, the ICD constant value data set of the intelligent local unit connected with the single-gap protection module can be directly added to the ICD constant value data set of the single-gap protection module, and specifically, the ICD constant value data set of the intelligent local unit connected with the single-gap protection module can be directly added to the back of the ICD constant value data set of the single-gap protection module.

For multi-interval protection modules, such as a main transformer protection module, a bus protection module, a spare power automatic switching protection module and the like, each multi-interval protection module is connected to a plurality of intelligent local units through a plurality of optical fibers, so that ICD fixed value data sets of each intelligent local unit connected with each multi-interval protection module are required to be combined and then added into the fixed value data set of the multi-interval protection module, and specifically, ICD fixed value data sets of a plurality of intelligent local units can be combined and then added into the back of the ICD fixed value data set of the multi-interval protection module.

Specifically, after adding the ICD constant value data set of the intelligent local unit connected with each protection module into the constant value database and the ICD file of the intelligent power server, adding GOOSE constant value receiving and transmitting virtual terminals into the ICD file of the intelligent power server and the ICD file of each intelligent local unit respectively.

And creating a connection relation between each protection module in the intelligent power server and the GOOSE fixed value receiving and transmitting virtual terminal of the intelligent local unit, namely a connection relation between each fixed value virtual terminal according to an SCD file formed by the intelligent power server and the ICD file of each intelligent local unit. For example, for a single-gap protection module, the single-gap protection module is connected to an intelligent local unit through only one optical fiber, and a GOOSE constant value sending virtual terminal of the single-gap protection module is directly connected to a GOOSE constant value receiving virtual terminal of the intelligent local unit, and a GOOSE constant value receiving virtual terminal of the single-gap protection module is connected to a GOOSE constant value sending virtual terminal of the intelligent local unit; for the multi-interval protection module, the multi-interval protection module is connected to a plurality of intelligent local units through a plurality of optical fibers, a GOOSE constant value sending virtual terminal of the multi-interval protection module is sequentially connected to GOOSE constant value receiving virtual terminals of m intelligent local units, and the GOOSE constant value receiving virtual terminals of the multi-interval protection module are connected to GOOSE constant value sending virtual terminals of m intelligent local units, wherein m can be any positive integer greater than 1, and the multi-interval protection module is not limited in the embodiment of the invention.

After the connection relationship between each protection module in the intelligent power server and the intelligent local unit is established, a CCD (loop instance configuration file, configured Circuit Description) file and a CID file of the intelligent power server and each intelligent local unit can be derived from an SCD file composed of ICD files of the intelligent power server and each intelligent local unit, and simultaneously the CCD file and the CID file are respectively downloaded to the intelligent power server and each intelligent local unit, and the SCD file is imported to the SCADA background.

In this embodiment, the SCD file of the intelligent power server is configured with a correspondence between each intelligent local unit and the optical ports of the intelligent power server, and a correspondence between the total-station multi-interval comprehensive measurement and control module and all the optical ports of the intelligent power server. The total station multi-interval comprehensive measurement and control module is specifically configured to receive a message reported by the intelligent local unit from each optical port according to configuration of the SCD file, and measure and control primary equipment connected with the intelligent local unit corresponding to each optical port according to the message.

Specifically, the SCD file of the intelligent power server is configured with the SV message and the GOOSE message of the intelligent local unit to which optical port, namely, the one-to-one correspondence between each intelligent local unit and the optical port of the intelligent power server, and the total station multi-interval comprehensive measurement and control module is also configured with the corresponding relationship between the total station multi-interval comprehensive measurement and control module and all the optical ports, wherein the SV message and the GOOSE message are acquired from all the optical ports.

That is, the total station multi-interval comprehensive measurement and control module uses all data of all optical ports, receives a GOOSE message and an SV message reported by an intelligent local unit corresponding to each optical port from each optical port according to SCD configuration, and measures and controls primary equipment connected with the intelligent local unit corresponding to each optical port respectively. The total station multi-interval comprehensive measurement and control module receives the message reported by the target optical port, and after analyzing the message, the corresponding intelligent on-site unit connected primary equipment is still measured and controlled through the target optical port.

Further, the SCD file of the intelligent power server is also configured with the corresponding relation between each protection module of the intelligent power server and the optical port of the intelligent power server; the protection module is specifically configured to receive a message reported by the intelligent local unit from an optical port corresponding to the SCD file according to configuration of the SCD file, and protect primary equipment connected with the intelligent local unit according to the message. For the single-interval protection module, receiving a message reported by an intelligent local unit from an optical port corresponding to the single-interval protection module according to the configuration of the SCD file, and protecting primary equipment connected with the intelligent local unit according to the message; and for the multi-interval protection module, receiving messages reported by a plurality of intelligent local units from a plurality of optical ports corresponding to the SCD file according to the configuration of the SCD file, and protecting primary equipment connected with the intelligent local units according to the messages.

Specifically, the SCD file of the intelligent power server is further configured with an SV message and a GOOSE message obtained by each protection module from which optical ports, that is, a one-to-one relationship (for a single-interval protection module) or a one-to-many correspondence (for a multi-interval protection module) between each protection module and an optical port of the intelligent power server.

Namely, the protection module receives the SV message and the GOOSE message from the optical port corresponding to the protection module according to the configuration of the SCD file, and protects the primary equipment of the intelligent on-site unit connected with the corresponding optical port according to the received SV message and GOOSE message. For the single-interval protection module, the single-interval protection module receives an SV message and a GOOSE message from one optical port corresponding to the single-interval protection module according to the configuration of the SCD file, and protects primary equipment of an intelligent on-site unit connected with the optical port according to the received SV message and the received GOOSE message; for the multi-interval protection module, the multi-interval protection module receives SV messages and GOOSE messages from a plurality of optical ports corresponding to the SCD files according to configuration of the SCD files, and protects primary equipment connected with an intelligent local unit connected with the optical ports according to the optical ports to which the received SV messages and GOOSE messages belong.

Further, the intelligent power server is in communication connection with the intelligent local unit through a pre-configured GOOSE fixed value receiving and sending virtual terminal, and is also connected with the SCADA background through an MMS (multimedia messaging service) (Manufacture Message Sepecification, manufacturing message specification) protocol, and according to a fixed value management command sent by the SCADA background, the fixed value of each protection module and the fixed value of the intelligent local unit connected with each protection module are managed.

Typically, the protection module of the intelligent power server is specifically configured to manage, according to the fixed value database of the intelligent power server, the ICD fixed value data set of the intelligent power server, and the fixed value management command of the SCADA background, the fixed value of the protection module and the fixed value of the intelligent local unit connected to the protection module.

Further, the protection module of the intelligent power server is further configured to identify, according to the fixed value database, a fixed value modification object that is matched with the fixed value modification command when it is determined that the fixed value management command of the SCADA background is the fixed value modification command, and if it is determined that the fixed value modification object is a target intelligent local unit, send, through a matched fixed value sending virtual terminal, a fixed value mutation message that is matched with the fixed value modification command to the target intelligent local unit.

Optionally, when the intelligent power server does not receive the fixed value modification command sent by the SCADA background, the GOOSE fixed value of each intelligent local unit is taken out from the fixed value database, and a corresponding GOOSE fixed value heartbeat message is sent to each intelligent local unit; the GOOSE constant value heartbeat message contains all constant values of the corresponding intelligent local unit. For example, the smart power server may send corresponding GOOSE-constant heartbeat messages to each smart local unit at set time intervals (e.g., 5 seconds).

When the SCADA background modifies the fixed value in the fixed value data set of a certain protection module of the intelligent power server through the IEC61850 protocol (comprising modifying the fixed value of the certain protection module and modifying the fixed value of an intelligent local unit connected with the certain protection module), the protection module receives a corresponding fixed value modification command and identifies a fixed value modification object matched with the fixed value modification command according to a fixed value database.

After receiving the fixed value modification command, the protection module firstly refreshes the Flash fixed value stored locally to obtain the fixed value of the local cache. Since the protection module cannot distinguish whether to modify the fixed value of the protection module or modify the fixed value of the intelligent local unit connected with the protection module according to the received fixed value modification command, the fixed value data set carried in the fixed value modification command needs to be compared with the fixed value data set of the local cache, so as to determine which module the fixed value to be modified belongs to (the protection module or the intelligent local unit connected with the protection module).

Specifically, the fixed value carried in the fixed value modification command is a fixed value data set, the fixed value locally cached by the protection module is also a fixed value data set, and each data element in the fixed value data set sequentially represents the fixed value of the protection module and the fixed value of each intelligent local unit connected with the protection module. After the protection module receives the fixed value modification command sent by the SCADA background, the fixed value data set carried in the fixed value modification command is compared with the fixed value data set of the local cache, and the object corresponding to the changed data element in the fixed value data set is the fixed value management object needing to modify the fixed value.

Specifically, if the fixed value management object matched with the fixed value modification command is a protection module, the fixed value of the RAM area of the protection module is refreshed once and immediately started.

Specifically, if the fixed value management object matched with the fixed value modification command is a target intelligent local unit in communication connection with the protection module, the virtual terminal can be sent through the GOOSE fixed value matched with the target intelligent local unit by the protection module, and a GOOSE fixed value mutation message matched with the fixed value modification command is sent to the target intelligent local unit. The GOOSE fixed value mutation message contains all fixed values of the target intelligent local unit. The target intelligent in-situ unit may be any intelligent in-situ unit communicatively connected to any protection module of the intelligent power server, which is not limited by the embodiment of the present invention.

In a specific example of the embodiment of the present invention, if it is determined that the fixed value modification object is a target intelligent local unit in communication connection, refreshing GOOSE sending data and a fixed value checksum of the target intelligent local unit, and setting a fixed value modification identifier matched with the target intelligent local unit to be in a valid state; and constructing and sending a GOOSE fixed value mutation message according to the fixed value modification identifier and the new fixed value of the data set in the fixed value modification command.

Specifically, if it is determined that the constant value modification object is the target intelligent local unit, the constant value modification identifier matched with the target intelligent local unit is set to be in a valid state, and for example, the constant value modification identifier matched with the target intelligent local unit may be set to be 1; further, according to the fixed value modification identifier and the new fixed value of the data set in the fixed value modification command, a GOOSE fixed value mutation message is constructed, and the GOOSE fixed value mutation message is sent to the target intelligent on-site unit.

If the intelligent power server protection module is a single-interval protection module, the target intelligent local unit is an intelligent local unit connected with the single-interval protection module through a GOOSE fixed value transceiving virtual terminal; if the intelligent power server protection module is a multi-interval protection module, the target intelligent local unit may be a plurality of intelligent local units connected with the multi-interval protection module through GOOSE fixed value transceiving virtual terminals.

And the intelligent on-site unit is used for executing the fixed value management operation corresponding to the GOOSE fixed value mutation message when receiving the GOOSE fixed value mutation message through the GOOSE fixed value receiving virtual terminal. Specifically, the intelligent local unit configures a fixed value corresponding to the intelligent local unit locally according to the received GOOSE fixed value mutation message. The constant value management operation corresponding to the GOOSE constant value mutation message may include: the fixed value is modified, a new fixed value is enabled, or the fixed value is stored in a local database.

Specifically, the intelligent local unit can identify a fixed value modification identifier matched with the intelligent local unit in the received message; if a constant value modification is identified as being in a valid state, for example, a constant value modification is identified as 1; the intelligent local unit acquires a target fixed value matched with the intelligent local unit from the received GOOSE fixed value mutation message, wherein the target fixed value can be any fixed value, any fixed value or all fixed values which need to be modified in the GOOSE fixed value mutation message. If the target fixed value is inconsistent with the fixed value of the intelligent local unit, modifying the fixed value corresponding to the intelligent local unit according to the target fixed value, and constructing a GOOSE fixed value mutation message according to the modified configuration result and feeding back the GOOSE fixed value mutation message to an intelligent power server in communication connection; if the target fixed value is consistent with the fixed value of the intelligent local unit, a GOOSE fixed value heartbeat message is constructed and transmitted back to the intelligent power server in communication connection.

It should be noted that, if the constant value modification flag is identified as an invalid state, for example, the constant value modification flag is 0; and constructing a GOOSE constant value heartbeat message and transmitting the heartbeat message back to the intelligent power server in communication connection.

Further, after sending a GOOSE fixed value mutation message matched with the fixed value modification command to the target intelligent local unit through the GOOSE fixed value sending virtual terminal, the protection module of the intelligent power server receives the GOOSE fixed value message returned by the target intelligent local unit; if the target intelligent local unit does not successfully complete the modification of the fixed value according to the comparison result of the GOOSE fixed value sending message and the GOOSE fixed value returning message, maintaining a fixed value modification identifier of the effective state in the sending message, and continuously sending a GOOSE fixed value heartbeat message to the target intelligent local unit through a GOOSE fixed value sending virtual terminal; if the target intelligent local unit is determined to be unsuccessful in completing the configuration of the fixed value within the set time length, reporting an alarm signal; and if the target intelligent local unit successfully completes the configuration of the fixed value according to the comparison result of the GOOSE fixed value sending message and the GOOSE fixed value returning message, setting the fixed value modification identifier of the target intelligent local unit to be in an invalid state. Illustratively, the target smart in-place unit's fixed value modification flag is set to 0.

Further, the intelligent power server is further configured to extract a fixed value of the intelligent power server and each intelligent local unit from the fixed value database and upload the fixed value to the SCADA background when it is determined that the fixed value management command of the SCADA background is a fixed value query command.

In the technical scheme provided by the embodiment of the invention, the intelligent power server is used for completing the protection, measurement and control and fixed value (fixed value of the intelligent power server and fixed value of each intelligent local unit) management of the whole station, and the intelligent local units do not need to be connected to equipment except the intelligent power server, so that the unified management of the whole station is realized, the software cost and the hardware cost are reduced, the communication path is reduced, and the reliability and the convenience are improved. In addition, the fixed value database of the intelligent power server and the ICD fixed value data set of the intelligent power server respectively comprise the ICD fixed value data set of the intelligent local unit connected with each protection module, the background modifies the fixed value of one protection module to only influence the function of the protection module, the functions of other protection modules are not influenced, and the background modifies the fixed value of one intelligent local unit to only influence the functions of the protection module connected with the intelligent local unit and not influence the functions of other intelligent local units.

Example two

Fig. 2 is a flowchart of a method for implementing a small current grounding line selection function by using the total station multi-interval integrated measurement and control module in the second embodiment of the present invention. On the basis of the technical scheme, the total-station multi-interval comprehensive measurement and control module in the intelligent power server provided by the embodiment also has a small-current line selection function.

The neutral point indirect grounding distribution network system comprises three modes of neutral point non-grounding (switch K is open), arc suppression coil grounding (switch K is closed) and resistance grounding (switch K is closed), and when a single-phase grounding fault occurs to a line or a bus, a small-current grounding line selection algorithm calculated based on the zero sequence voltage 3U0 of the bus and the zero sequence current 3I0 of each line is adopted to determine the line with the single-phase grounding fault.

The low-current grounding line selection algorithm calculated based on the bus zero-sequence voltage 3U0 and the zero-sequence current 3I0 of each line can be roughly divided into two main algorithms based on transient sampling values and two main algorithms based on filtering values. The algorithm based on the transient sample value comprises: a first half-wave method, a transient capacitive current direction method, a transient energy integration method, a traveling wave method, a parameter identification method, a model identification method and the like; the filtered value based algorithm includes: the zero sequence current group amplitude/phase comparison method, the fifth harmonic method, the zero sequence active power direction method, the wavelet analysis method, the waveform transformation method (S transformation and Hilbert transformation), the frequency band analysis method and the like.

However, these algorithms have different requirements on sampling frequency and applicable neutral point grounding modes, for example, the parameter identification method and the wavelet analysis method generally require that the sampling rate is more than 20K (1000 points per week), and the zero sequence current group amplitude/phase comparison method is only applicable to the situation that the neutral point is not grounded, so that a single line selection algorithm is difficult to adapt to the situations of different neutral point grounding modes, different transition resistances, different fault moments and the like of a distribution network. In the existing comprehensive line selection algorithm, 2-3 kinds of algorithms are adopted, but the comprehensive line selection algorithm is switched and used only according to different neutral point grounding modes, and still is difficult to adapt to the situations of different neutral point grounding modes, different transition resistances, different fault moments and the like of a distribution network.

In this embodiment, the total station multi-interval comprehensive measurement and control module is used for integrating the line selection results of different types of line selection algorithms to determine the single-phase grounding fault line selection alarm information of the intelligent power server, so as to realize the small current line selection function. The technical scheme is a comprehensive general low-current grounding line selection scheme, and is suitable for the situations of different neutral point grounding modes, different transition resistances, different fault moments and the like of a power distribution network.

Before the technical scheme of the embodiment is implemented, firstly, configuration is performed on input and output information of a process layer:

the intelligent power server is accessed to SV and GOOSE data of 10KV at intervals in a point-to-point mode, wherein the specific access mode is that after ICD files of the power distribution station server and ICD files of intelligent local units are imported into SCD files, connection relations of SV/GOOSE virtual terminals are established, then CID files are exported respectively, and the ICD files are downloaded to the intelligent power server and each intelligent local unit. The SV dummy terminals for each interval include: ua, ub, uc, 3U0, ia, ib, ic, 3I0 (where 3U0 is from a 10KV bus interval), GOOSE input dummy terminals of each interval including circuit breaker double-point positions and the like, GOOSE output dummy terminals including circuit breaker trip and closing outlets and the like.

And then establishing storage space of various data:

establishing a sampling value storage space of 3U0 and n lines 3I0 with set frequency, taking 3 frequency as an example, and establishing a sampling value storage space of 240 points at 80 points per frequency; and establishing n lines, m kinds of classified line selection result storage spaces R [ m ] [ n ], establishing comprehensive line selection result storage spaces A [ n ] and the like. Because fundamental waves, harmonic waves and the like are required to be calculated when the line selection algorithm is applied, storage spaces of real parts, imaginary parts, amplitude values and the like of the fundamental waves and 5 th harmonic waves of n lines are also required to be established.

As shown in fig. 2, the method for implementing the small-current grounding line selection function by the total station multi-interval comprehensive measurement and control module includes:

and S210, after the busbar zero sequence voltage abrupt change starting element acts, caching sampling values of busbar zero sequence voltages of set frequency numbers and sampling values of zero sequence currents of all lines in the fault transient process.

The busbar zero sequence voltage abrupt change starting element is used for distinguishing the occurrence time of the single-phase earth fault so as to determine an SV data window for calculation.

Specifically, a 3U0 abrupt change starting element may be designed by using the bus zero sequence voltage, and is used to determine whether the abrupt change of 3U0 is greater than a set threshold:

|3U0 _k -3U0 _k-2N |＞3U0 _set

wherein 3U0 _k For the sampling value of the bus 3U0 voltage at the current moment, 3U0 _k-2N For the bus 3U0 voltage, the sampling value is sampled before two cycles (such as N=80 points/cycle), 3U0 _k And 3U0 _k-2N The difference of (2) is 3U0, and 3U0set is the threshold for starting the abrupt change.

Since the maximum voltage of the bus 3U0 can reach 3 times of the phase voltage when the single-phase grounding fault occurs, the 3U0set can be set to 20V to ensure that the starting element has enough sensitivity when the single-phase grounding fault occurs through high resistance and can not be started by mistake when the three-phase voltage is unbalanced.

After the 3U0 abrupt change starting element acts, caching sampling values of bus zero sequence voltage of set frequency numbers and zero sequence currents of all lines. Taking the setting of the cycle number as 3 cycles as an example, 80 points per cycle, the sampling value of the buffer busbar 3U0 is 240 points, and the sampling value of each buffer line 3I0 is 240 points.

Since the SV value is constantly changing, the buffer means to lock the transient process data window after the single-phase ground fault occurs, so that different kinds of line selection algorithms can use fault latch data to calculate, especially to perform time-sharing calculation.

S220, calculating and outputting a classified line selection result array corresponding to each line selection algorithm on the sampling value of the bus zero sequence voltage and the sampling value of each line zero sequence current by using different types of line selection algorithms.

And carrying out low-current grounding line selection calculation by using different types of multiple line selection algorithms and adopting sampling values of the bus zero sequence voltage and sampling values of the zero sequence currents of all lines respectively. Wherein a plurality of line selection algorithms of different kinds are predetermined.

Each of the classified line selection result arrays includes n elements, which are respectively corresponding to line selection results of n lines, for example, if a line selection result of a certain line is a faulty line, the corresponding element in the classified line selection result array is 1, and if a line selection result of a certain line is a non-faulty line, the corresponding element in the classified line selection result array is 0. Specifically, all the classified line selection result arrays can be represented by Rm n, where m represents the total number of line selection algorithms and n represents the total number of lines.

As a specific implementation manner of this embodiment, the sampling rate of sampling values of the bus zero-sequence voltage and the zero-sequence current of each line is 80 points per wave. Wherein, 80 points per cycle are standard SV sampling rate output by the merging unit or the intelligent unit, and the sampling is not needed to be independently sampled by the power distribution station server.

Correspondingly, the sampling value of the bus zero sequence voltage and the sampling value of each line zero sequence current by using different types of line selection algorithms are calculated and output into a classified line selection result array corresponding to each line selection algorithm, and the method specifically comprises the following steps: and calculating and outputting a classified line selection result array corresponding to each line selection algorithm on the sampling value of the bus zero-sequence voltage and the sampling value of the zero-sequence current of each line by using a first half-wave method, a zero-sequence active component direction method, a transient capacitive current direction method, a transient energy integration method, a zero-sequence current group comparison method and a 5-harmonic group comparison method.

In other words, in this embodiment, in order to adapt to the sampling rate of the SV data received by the measurement and control module of the power distribution station server at 80 points per cycle and consider three neutral point grounding modes, six line selection algorithms, i.e., a first half-wave method, a zero-sequence active component direction method, a transient capacitive current direction method, a transient energy integration method, a zero-sequence current group amplitude comparison method and a 5-harmonic group amplitude comparison method, are selected to perform the small-current grounding line selection calculation respectively. The array of sorting line selection results generated by these six line selection algorithms is R6 n.

Regarding the first half-wave method:

the method is based on the assumption that single-phase earth faults occur when the phase voltage is close to the maximum value, transient zero-sequence current of a fault line is caused by capacitor discharge with reduced fault phase voltage, and transient zero-sequence current of a non-fault line is caused by capacitor charge with increased non-fault phase voltage, so that the characteristic that the first half wave of the transient zero-sequence current is opposite after the fault can be utilized to judge the fault line. For any line j, calculating the following criteria from two continuous points after the 3U0 starting element action moment, if the two continuous points simultaneously meet the following criteria: (3U 0) _k -3U0 _k-1 )×(3I0 _jk -3I0 _j(k-1) ) If the value is less than 0, the line selection result of the line j is set to be 1 (fault line), otherwise, the line selection result of the line j is set to be 0 (non-fault line), and the line selection result is correspondingly stored in a classified line selection result array R [0 ] corresponding to the first half-wave method][j](j=0, …, n-1).

Regarding the zero sequence active component direction method:

for a system with neutral points grounded through a resistor or arc suppression coil parallel (series) resistor, zero sequence active component current (phase lag zero sequence voltage 90 DEG) only flows through a fault line when single-phase grounding occurs, and non-fault line only flows through capacitive reactive component current (phase lead zero sequence voltage 90 DEG); for a neutral point ungrounded system, when single-phase grounding occurs, the fault line and the non-fault line only flow capacitive current and have opposite directions, and the method can be adopted for converting zero-sequence current into active components after phase shifting. Firstly, calculating fundamental wave real parts and imaginary parts of one cycle of 3U0 and n lines after faults (after the 3U0 starting element acts), and marking as: 3 u0=u0 _R +jU0 _X ，3I0 _j ＝I0 _jR +jI0 _jX . For any one lineRoad j, if satisfied: u0 _R ×I0 _jR +U0 _X ×I0 _jX Setting the line selection result of the line j as 1 (fault line) if the value is more than 0, otherwise setting the line selection result of the line j as 0 (non-fault line), and correspondingly storing a classified line selection result array R [1 ] corresponding to the zero sequence active component direction method][j](j=0, …, n-1).

Regarding the transient capacitive current direction method:

based on the characteristic that transient inductive current can not be suddenly changed in a neutral point through arc suppression coil grounding system, the method extracts the construction parameters of the transient capacitive current direction to judge the fault line, so that the method is suitable for all low-current grounding systems. For any line j, calculating the parameter integral value of the cycle after the fault, if the parameter integral value meets the following conditions:n is the number of points per cycle, N=80, then the line j's line selection result is set to 1 (fault line), otherwise the line j's line selection result is set to 0 (non-fault line), and the classified line selection result array R2 corresponding to transient capacitive current direction method is stored correspondingly][j](j=0, …, n-1).

Regarding the transient energy integration method:

the method is based on the characteristic that after single-phase grounding faults occur in a small-current grounding system with various neutral point grounding modes, only a fault line releases transient energy, and a non-fault line or a neutral point grounding line through an arc suppression coil (or a resistor) absorbs the transient energy. For any line j, calculating the energy integral value of two cycles after the fault, if: N is the number of points per cycle, N=80, then the line j's line selection result is set to 1 (fault line), otherwise the line j's line selection result is set to 0 (non-fault line), and the line selection result is correspondingly stored into the classified line selection result array R3 corresponding to the transient energy integration method][j](j=0, …, n-1).

Regarding the zero sequence current group amplitude comparison method:

at neutralityIn the point ungrounded system, the zero sequence current of the fault line is the sum of the capacitance currents of all non-fault lines, so that the zero sequence current of the fault line is the largest; in a neutral point through resistance grounding system, the zero sequence current of the fault line is the capacitance current of all non-fault lines plus the resistive current of the neutral point, so that the zero sequence current of the fault line is also the maximum; but this method is not applicable to neutral point via arc suppression coil grounding systems. Firstly, calculating the zero sequence fundamental current amplitude |3I0 of each circuit _j The zero sequence fundamental wave amplitude values of n lines are sequenced, the lines with the maximum value at the first few bits (for example, the first three bits) are selected, the line selection results of the lines are set as 1 (fault line), the line selection results of other lines are set as 0 (non-fault line), and the classified line selection result array R4 corresponding to the zero sequence current group amplitude comparison method is correspondingly stored ][j](j=0, …, n-1).

Regarding the 5 th harmonic group amplitude comparison method:

the principle is based on that in a neutral point through arc suppression coil grounding system, the impedance of the arc suppression coil to 5 th harmonic is 5 omega L, the impedance of other lines to 5 th harmonic is 1/5 omega C, and 5 th harmonic current generated by a fault point mainly flows through a non-fault line and rarely flows to the neutral point, so that the 5 th harmonic current of the fault line is approximately equal to the sum of 5 th harmonic currents of all non-fault lines, and the method is also applicable to a neutral point non-grounding system. Firstly, calculating the zero sequence 5-order current amplitude value |3I05 of each line _j The 5 th harmonic amplitude values of the n lines are sequenced, the lines with the first few digits (such as the first three digits) of the maximum value are selected, the line selection results of the lines are set as 1 (fault line), the line selection results of other lines are set as 0 (non-fault line), and the line selection results are correspondingly stored in a classified line selection result array R [5 ] corresponding to the 5 th harmonic group amplitude comparison method][j](j=0, …, n-1).

S230, outputting single-phase grounding fault line selection alarm information of the intelligent power server according to the classified line selection result arrays corresponding to the line selection algorithms.

Specifically, according to the classified line selection result arrays corresponding to the line selection algorithms, a comprehensive line selection result array is calculated and output, and according to the comprehensive line selection result array, single-phase earth fault line selection alarm information of the power distribution station server is output.

The comprehensive line selection result array is obtained by calculating according to the classified line selection result data corresponding to different types of line selection algorithms, for example, the comprehensive line selection result array is obtained by calculating each classified line selection result array corresponding to different types of line selection algorithms by using a fuzzy weighted average algorithm, and typically, when the comprehensive line selection result array is obtained by calculating according to each classified line selection result array, the weight of each classified line selection result array is different.

As an optional implementation manner of this embodiment, the comprehensive line selection result array is obtained by calculating the classified line selection result array corresponding to each line selection algorithm, which specifically includes:

acquiring the weight of each line selection algorithm; and calculating the classified line selection result arrays corresponding to the line selection algorithms by adopting a fuzzy weighted average algorithm method to obtain the comprehensive line selection result arrays.

Wherein the weight of each line selection algorithm is set.

The weight of each line selection algorithm is represented by an array W [ l ] (l is the total number of line selection algorithms), and by taking six line selection algorithms as examples, the weights of the six line selection algorithms are represented by W [0], W [1], W [2], W [3], W [4], W [5], respectively.

The result arrays of the six kinds of line selection algorithms are R0 respectively ][n]、R[1][n]、R[2][n]、R[3][n]、R[4][n]、R[5][n]Calculating the comprehensive line selection result of n lines by adopting a fuzzy weighted average formula, and for any line j, comprehensively selecting a line result array

Taking the first half-wave method, the zero sequence active component direction method, the transient capacitive current direction method, the transient energy integration method, the zero sequence current group amplitude comparison method and the 5 th harmonic group amplitude comparison method as examples, the small current grounding line selection calculation is performed by six line selection algorithms respectively, and W [0], W [1], W [2], W [3], W [4] and W [5] can be expressed as the initial weight values of the six line selection algorithms in sequence, for example, W [0] = 0.3, W [1] = 0.2, W [2] = 0.2, W [3] = 0.1, W [4] = 0.1 and W [5] = 0.1. Wherein, the initial weight of each line selection algorithm is determined according to the characteristics of various line selection algorithms. For example, the first half-wave method has the most extensive adaptability, and the initial weight value of the line selection algorithm is set to be larger.

Furthermore, the weight of each line selection algorithm can be a final weight obtained by performing test fine adjustment on the small current grounding line selection algorithm through the fault simulation of a real-time digital simulator of the small current grounding system on the basis of the initial weight of each line selection algorithm.

For example, after initial weights are determined for the line selection algorithms, a simulation model of the low-current grounding system is established through an RTDS (Real Time Digital Simulator, real-time digital simulator), fault simulation is performed through the simulation model, so that fine adjustment is performed on each element in the array W [ l ] according to the fault simulation result, and then the weight final value of each line selection algorithm is determined. And determining an integrated line selection result array based on the weight final value of each line selection algorithm, so that the accuracy of low-current grounding line selection can be provided.

In the technical scheme, the six line selection algorithms, namely the first half-wave method, the zero sequence active component direction method, the transient capacitive current direction method, the transient energy integration method, the zero sequence current group comparison method and the 5-harmonic group comparison method, are selected, the sampling rate requirement is not too high, the existing 80-point sampling rate can be applied, the method can be simultaneously adapted to different neutral point grounding modes, a weighted average algorithm similar to the fuzzy recognition technology is adopted, and a large number of samples are not needed for weight training like a fuzzy recognition system.

After the comprehensive line selection result array A [ n ] is obtained, determining a line with single-phase grounding faults according to the sizes of elements in the array A [ n ].

Specifically, if a target element with the value larger than a set threshold exists in the comprehensive line selection result array, determining that a line corresponding to the target element is a line with single-phase earth fault, and outputting single-phase earth fault line selection alarm information of the line corresponding to the target element;

and if the target element with the value larger than the set threshold value does not exist in the comprehensive line selection result array, determining that the bus is a line with single-phase earth fault, and outputting single-phase earth fault line selection alarm information of the bus.

On the basis of the foregoing example, the set threshold value may be set to 0.6.

The array A [ n ] comprises n elements, which are the line selection results of n lines respectively, and the line selection results are respectively represented by elements A [ j ], j=0, … and n-1. And comparing the line selection results of the n lines, selecting the maximum value A [ s ] among the n lines, determining the line corresponding to A [ s ] as a fault line if A [ s ] is more than 0.6, and determining the bus as the fault line if A [ s ] is less than 0.6. In the extreme case, two lines are determined to be faulty lines, that is, the line selection results aj of the two lines are all greater than 0.6.

Further, if the line corresponding to the target element is a line with single-phase grounding fault, outputting a single-phase grounding alarm signal of the line corresponding to the target element, or outputting a GOOSE trip signal of the line corresponding to the target element; and if the bus is a line with single-phase earth fault, outputting an earth alarm signal of the bus.

After determining that the line s is a fault line, the method can directly output an SOE or a GOOSE of the single-phase grounding alarm action of the line s; after determining that the bus is a fault line, the bus grounding alarm action SOE can be directly output.

On the basis of the above technical solution, as an optional implementation manner, the method may further calculate the sampling value of the bus zero-sequence voltage and the sampling value of each line zero-sequence current by using different types of line selection algorithms to obtain a classified line selection result array corresponding to each line selection algorithm, where the method specifically includes:

determining each target line put into operation in each line, wherein the target line breaker position GOOSE input signal is required to be in a combined position, or the sampling value of the zero sequence current of the target line is greater than a set threshold value;

calculating sampling values of the bus zero sequence voltage and sampling values of the line zero sequence currents by using different types of line selection algorithms, and outputting a classified line selection result array corresponding to each line selection algorithm; and storing the classified line selection results corresponding to the marked lines of each item in the classified line selection result array.

For n lines connected to the distribution station server, whether the lines are put into operation or not can be judged first, and the lines which are not put into operation can not participate in line selection, so that the calculated amount of a line selection algorithm is reduced. Specifically, if a line breaker position GOOSE input signal is in a split state, or SV data of its zero sequence current is close to zero, the line is not a target line, and no participation in line selection is required. If the GOOSE input signal of one line breaker is in the combining position or the SV data of the zero sequence current is larger than the set threshold value, the line is a target line and needs to participate in line selection.

Assuming that two lines in n lines connected to the distribution station server are not put into operation, namely, only n-2 lines are used as target lines, the classified line selection result arrays of different line selection algorithms are R < m > [ n-2], and the comprehensive line selection result arrays are A < n-2 >, wherein the line selection results of only n-2 lines are included.

Furthermore, the sampling value of the bus zero-sequence voltage and the sampling value of each line zero-sequence current by using different types of line selection algorithms can be calculated and output into a classified line selection result array corresponding to each line selection algorithm, which specifically comprises: and applying different types of line selection algorithms to time-sharing calculation of sampling values of the bus zero-sequence voltage and sampling values of the zero-sequence currents of all lines to output a classified line selection result array corresponding to each line selection algorithm.

The submodule for realizing the low-current grounding line selection function is integrated in the total-station multi-interval comprehensive measurement and control module. Namely, a grounding line selection software module is added in a total station multi-interval comprehensive measurement and control module of the intelligent power server to complete a small-current grounding line selection function, and the device is different from two types of line selection devices (one is a special small-current line selection device and the other is a device which needs to receive other device information) which are commonly used at present. The grounding line selection software module is a subtask of the total-station multi-interval comprehensive measurement and control module, and the total-station multi-interval comprehensive measurement and control module is supposed to sequentially execute (order is irrelevant) 6 subtasks after the grounding line selection subtask is added to the original 5 subtasks of the total-station multi-interval comprehensive measurement and control module.

The submodule for realizing the small-current grounding line selection function is integrated in a total-station multi-interval comprehensive measurement and control module of the intelligent power server, certain software execution time is required to be occupied, in order to ensure that the execution time of each measurement and control interrupt is controlled below a certain duty ratio, the interrupt execution time is prevented from overtime, after a 3U0 mutation starting element is adopted to act, 3U0 and n lines 3I0 sampling value data windows are firstly locked, then various line selection criteria are calculated in a time-sharing mode, comprehensive line selection results are calculated, and finally the 3U0 mutation starting element is re-opened for the next grounding fault line selection.

Specifically, the input data of the submodule for realizing the small-current grounding line selection function is the zero-sequence voltage 3U0 of a 10KV bus and the SV data of the zero-sequence currents 3I0 (3I 01, 3I02, … and 3I0 n) of each line, the output data of the submodule is the grounding alarm SOE of each line and bus, and the GOOSE tripping signal of the grounding line can be directly output according to the situation.

In the technical scheme, the single-phase grounding fault line selection alarm information of the power distribution station server is determined by integrating the line selection results of different types of line selection algorithms, the single-phase grounding fault line selection alarm information is not determined on the basis of the line selection result of one line selection algorithm, and the single-phase grounding fault line selection alarm information is not determined by selecting one of a plurality of line selection methods, so that the single-phase grounding fault line selection alarm information can adapt to the conditions of different neutral point grounding modes, different transition resistances, different fault moments and the like of the power distribution network. In addition, the embodiment of the invention adds a grounding line selection software module to complete the grounding line selection function in the total station multi-interval comprehensive measurement and control module of the intelligent power server by utilizing the existing input conditions, and does not need to increase extra hardware cost.

Example III

Fig. 3 is a schematic structural diagram of an electric power protection measurement and control system in a third embodiment of the present invention. The embodiment may be applicable to the case of protecting and managing the fixed value of the intelligent local unit in the intelligent substation, and the fixed value management function of the intelligent local unit may include: checking a fixed value, modifying the fixed value, checking the fixed value, communicating the fixed value, storing the fixed value and the like. Specifically, as shown in fig. 3, the system includes an intelligent power server 1 according to any embodiment of the present invention, and a plurality of intelligent in-situ units 2 connected to the intelligent power server 1.

Wherein the intelligent local unit 2 has an intelligent unit combining function and a local protection function; when the intelligent local unit 2 communicates with the protection module of the intelligent power server 1 normally, the intelligent local unit performs an intelligent unit closing function and locks the local protection function; the intelligent in-situ unit 2 performs an intelligent unit function and opens an in-situ protection function when communication with the protection module of the intelligent power server 1 fails.

The intelligent in-situ unit is an integrated device of the merging unit and the intelligent terminal, and is also called an intelligent integrated unit. In this embodiment, the intelligent in-situ unit takes on the role of collecting and uploading GOOSE/SV at each interval to the substation server in situ, executing a GOOSE tripping and closing command from the substation server, and takes on the role of in-situ backup protection, that is, the intelligent in-situ unit enables in-situ protection function when the protection module of the intelligent power server connected with the intelligent in-situ unit fails.

As shown in fig. 4, the core chip of the intelligent local unit adopts a combination of a high-performance FPGA (Field Programmable Gate Array ) and a CPU (Central Processing Unit, central processing unit), and the FPGA and the CPU are connected and communicated through an ethernet port. The FPGA outputs two optical ports (for example, hundred megaoptical ports) and 1 electric B code time synchronization port to the outside, the optical ports are used for connecting a protection device of the intelligent power server to carry out SV/GOOSE communication, and the FPGA is also connected to a PTCT (voltage current transformer) module, a DIDO (digital input output) module and an electric B code input port; the CPU outputs two Ethernet ports to the outside for connecting background and maintenance software, and is also connected to the HMI module (mainly LED).

The FPGA is used for completing AD sampling and SV sending of the PTCT module, DI acquisition and GOOSE sending of the DIDO module, GOOSE receiving and DO driving functions of the protection device, and finishing analysis of IRIG-B time setting signals of the receiving electric B code port, finishing time setting functions and the like. The CPU completes the on-site backup protection function, 61850 server function and maintenance function, wherein the backup protection function comprises three-section inter-phase/grounding distance protection, three-section double-voltage direction overcurrent protection, two-section zero sequence overcurrent protection, reclosing, post acceleration protection and other functions. The communication content between the FPGA and the CPU comprises GOOSE/SV information, time scale information and the like.

Specifically, the FPGA outputs two optical ports to the outside, and has the functions of judging the communication state by using a GOOSE heartbeat message, receiving time setting information of the protection device by using a GOOSE time scale and the like besides the SV/GOOSE common port transmission function of the conventional intelligent unit; the two Ethernet ports of the CPU can be used for connecting the background to perform functions of remote signaling and telemetry uploading, protection fixed value modification, recording file uploading and the like, and also can be used for connecting the maintenance software to perform functions of parameter configuration, software downloading and the like.

Typically, when GOOSE communication between the intelligent local unit and the protection device is normal, the intelligent local unit performs the function of the intelligent unit, locks the local protection function, and completes the protection function of the local interval fault by the protection device; when the intelligent local unit and the protection device GOOSE have communication faults, the intelligent local unit can execute the function of the intelligent unit and also can start the function of local protection, and the intelligent local unit can complete the protection of local interval faults.

As a specific implementation manner, when the intelligent in-situ unit fails to communicate with the protection module of the intelligent power server, the in-situ protection function is started, which may be specifically: when the FPGA of the intelligent local unit cannot detect the heartbeat message of the protection module of the intelligent power server, the communication fault between the intelligent local unit and the protection module of the intelligent power server is determined, and the CPU is informed to start the local protection function through the embedded Ethernet, for example, the FPGA can be informed to start the local protection function through the embedded communication interface with the CPU.

Specifically, when the protection device fails, the sending of the GOOSE heartbeat message to the intelligent local unit is stopped, and when the FPGA cannot detect the GOOSE heartbeat message of the protection device of the intelligent power server at the hundred megalight port, the FPGA determines that the intelligent local unit is in communication failure with the protection module of the intelligent power server, sends an local protection signal to the CPU through the embedded Ethernet port, and notifies the CPU to start the local protection function.

Typically, when the intelligent local unit receives the electrical B code, the timing is performed according to an external clock device (i.e., according to the electrical B code), and when the electrical B code is not received, the timing may be performed according to the received GOOSE time stamp. Specifically, when the FPGA does not receive the IRIG-B time setting signal at the electric B code time setting port, the FPGA receives the GOOSE time mark sent by the protection device from the hundred megalight port, and reports the GOOSE time mark to the CPU through the Ethernet port, and the CPU completes time setting by using the GOOSE time mark.

Further, after the in-situ protection function is started, when the target interval fails, the intelligent in-situ unit can identify the direction and the section of the failure of the target interval through the distance protection element and/or the overcurrent protection element, and execute corresponding protection actions. The distance protection element can be three-section phase-to-phase or grounding distance protection; the directional overcurrent protection element can be three-section type double-voltage directional overcurrent protection or two-section type zero-sequence directional overcurrent protection. It should be noted that, the distance protection and the overcurrent protection related to the embodiment of the present invention may further include other protection elements, which are not limited in the embodiment of the present invention.

Note that the above is only a preferred embodiment of the present invention and the technical principle applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, while the invention has been described in connection with the above embodiments, the invention is not limited to the embodiments, but may be embodied in many other equivalent forms without departing from the spirit or scope of the invention, which is set forth in the following claims.

Claims

1. An intelligent power server for an intelligent substation or substation protection control system, comprising: a total station multi-interval comprehensive measurement and control module and a plurality of protection modules, wherein,

The intelligent power device capacity description ICD fixed value data set of the intelligent power server and the intelligent power device capacity description ICD fixed value data set of the intelligent power server respectively comprise ICD fixed value data sets of intelligent local units connected with the protection modules; the ICD fixed value data sets of different protection modules are distinguished through module numbers in the addresses of the ICD fixed value data sets;

the single-interval protection module is connected with an intelligent local unit through an optical port on the intelligent power server; the multi-interval protection module is connected with a plurality of intelligent local units through a plurality of optical ports on the intelligent power server; the fixed value transmitting virtual terminal of the single-interval protection module is connected with the fixed value receiving virtual terminal of the intelligent local unit connected with the fixed value transmitting virtual terminal of the single-interval protection module, and the fixed value receiving virtual terminal of the single-interval protection module is connected with the fixed value transmitting virtual terminal of the intelligent local unit connected with the fixed value receiving virtual terminal of the single-interval protection module; the fixed value transmitting virtual terminals of the multi-interval protection module are respectively connected with the fixed value receiving virtual terminals of the plurality of intelligent local units connected with the fixed value transmitting virtual terminals of the multi-interval protection module;

The protection module is specifically configured to manage a fixed value of the protection module and a fixed value of the intelligent local unit connected with the protection module according to a fixed value database of the intelligent power server, an ICD fixed value data set of the intelligent power server, and a fixed value management command of a SCADA background of a data acquisition and monitoring control system;

and the protection module is further used for identifying a fixed value modification object matched with the fixed value modification command according to the fixed value database when the fixed value management command is determined to be the fixed value modification command, and sending a fixed value mutation message matched with the fixed value modification command to the target intelligent on-site unit through a fixed value sending virtual terminal matched with the fixed value modification object if the fixed value modification object is determined to be the target intelligent on-site unit.

2. The intelligent power server according to claim 1, wherein the total station multi-interval comprehensive measurement and control module is further configured to synthesize line selection results of different types of line selection algorithms to determine single-phase ground fault line selection alarm information of the intelligent power server.

3. The intelligent power server according to claim 1, wherein,

for the single-interval protection module, adding the ICD constant value data set of the intelligent local unit connected with the single-interval protection module into the constant value data set of the single-interval protection module;

And for the multi-interval protection module, merging ICD fixed value data sets of all intelligent local units connected with the multi-interval protection module, and adding the merged ICD fixed value data sets into the fixed value data set of the multi-interval protection module.

4. The intelligent power server according to claim 1 or 2, wherein,

the substation configuration description SCD file of the intelligent power server is configured with the corresponding relation between each intelligent local unit and the optical ports of the intelligent power server, and the corresponding relation between the total station multi-interval comprehensive measurement and control module and all the optical ports of the intelligent power server;

the total station multi-interval comprehensive measurement and control module is specifically configured to receive a message reported by the intelligent local unit from each optical port according to configuration of the SCD file, and measure and control primary equipment connected with the intelligent local unit corresponding to each optical port according to the message.

5. The intelligent power server according to claim 1 or 2, wherein,

the substation configuration description SCD file of the intelligent power server is also configured with the corresponding relation between each protection module of the intelligent power server and the optical port of the intelligent power server; wherein,

The protection module is specifically configured to receive a message reported by the intelligent local unit from an optical port corresponding to the SCD file according to configuration of the SCD file, and protect primary equipment connected with the intelligent local unit according to the message;

for the single-interval protection module, receiving a message reported by an intelligent local unit from an optical port corresponding to the SCD file according to configuration of the SCD file, and protecting primary equipment connected with the intelligent local unit according to the message;

and for the multi-interval protection module, receiving messages reported by a plurality of intelligent local units from a plurality of optical ports corresponding to the SCD file according to the configuration of the SCD file, and protecting primary equipment connected with the intelligent local units according to the messages.

6. A power protection measurement and control system comprising the intelligent power server of any one of claims 1-5, and a plurality of intelligent in-situ units accessing the intelligent power server;

7. The power protection measurement and control system of claim 6, wherein the intelligent in-situ unit turns on an in-situ protection function upon a communication failure with a protection module of the intelligent power server, comprising:

and when the heartbeat message of the protection module of the intelligent power server cannot be detected by the optical port, the FPGA of the intelligent local unit determines that the communication fault between the intelligent local unit and the protection module of the intelligent power server occurs, and informs the CPU to start the local protection function through the embedded Ethernet.

8. The power protection and measurement and control system according to claim 7, characterized in that the intelligent in-situ unit, after switching on the in-situ protection function, when a fault occurs in a target interval, recognizes the direction and section of the fault in the target interval by means of a distance protection element and/or an overcurrent protection element and performs a corresponding protection action.