CN101667730A - Method for monitoring and managing electrical energy quality of electric distribution network - Google Patents

Abstract

The invention provides a method for monitoring and managing the electrical energy quality of an electric distribution network, which comprises the following steps of: inputting an electric load characteristic parameter and a system parameter; carrying out simulation calculation of the electrical energy quality; comparing a calculation result with an index limit of the electrical energy quality, and judging whether the calculation result accords with the index limit; and taking an electrical energy quality improving measure if the calculation result does not accords with the index limit.

Description

Method for monitoring and managing electrical energy quality of electric distribution network

Technical field

The present invention relates to a kind of supervisory methods, and be particularly related to a kind of method for monitoring and managing electrical energy quality of electric distribution network.

Background technology

Along with the high speed development of industry, the power load that application in recent years inserts electric power system gets more and more.Because the load character that application inserts is varied, in order to guarantee the public electric power system quality of power supply, safeguards all electricity consumption clients' just rights and interests, electric company need bear the responsibility that customer charge character is assessed and supervised.

Because the nonlinear-load among the electricity consumption client is more and more, the electric power system harmonics level is more outstanding, and according to State Grid's method and " power supply and business rules " the 55 regulation: the harmonic current that electrical network points of common connection voltage sinusoidal wave distortion rate and user inject electrical network must not surpass the regulation of standard GB/T14549-93.

At present, also be in the program and the method for standard for the load electricity quality evaluation that inserts electric power system of electricity consumption client, individual customer individual treated often, efficient is not high, and program is lack of standardization, is unfavorable for supervision and management.

Summary of the invention

The present invention proposes a kind of method for monitoring and managing electrical energy quality of electric distribution network, can address the above problem.

In order to achieve the above object, the present invention proposes method for monitoring and managing electrical energy quality of electric distribution network, comprises the steps: to import power load characterisitic parameter and system parameters; Carry out quality of power supply simulation calculation; Result of calculation and power quality index limit value are compared, judge whether result of calculation meets the index limit value; And if the result of previous step for not, takes quality of power supply corrective measure.

Optionally, this method also comprises when judging that result of calculation meets the index limit value, this power load is inserted electrical network

Optionally, this method also comprises after this power load inserts electrical network, and this power load is carried out the power quality index actual measurement; And, take quality of power supply corrective measure if results measured does not meet the requirement of index limit value.

Optionally, wherein quality of power supply corrective measure comprises: for the user who belongs to non-linear pollutional load, require harmonic wave control scheme, resolution assessment are examined, formulated to power supply plan; Requirement may produce the user installation electric energy quality monitor that the quality of power supply is polluted; And out-of-limit user's time limit is administered.

Optionally, wherein this power quality index limit value is provided by power supply enterprise.

Beneficial effect of the present invention is, for quality of power supply interference load for the impact evaluation of the electric power system quality of power supply and the supervision of load is provided the flow process and the method for a cover standard, angle from technology guarantees that the quality of power supply of electrical network remains in the scope that does not influence the normal operation of all electricity consumption clients on the one hand, from the supervision and management of angle reinforcement to loading of management, improve the safety and economic operation level of electrical network on the other hand.

Description of drawings

Figure 1 shows that the device schematic diagram of distribution network electric energy quality monitoring management system.

Figure 2 shows that the inputting interface schematic diagram of client.

Figure 3 shows that the method for monitoring and managing electrical energy quality of electric distribution network flow chart.

Embodiment

Supervise the regulation of rules for power quality index according to the national standard and the quality of power supply, power quality index comprises frequency, voltage deviation, voltage fluctuation and flickering, tri-phase unbalance factor, these five indexs of harmonic wave.Harmonic wave, voltage fluctuation and flickering and tri-phase unbalance factor produce owing to electrical network is subjected to effects of load often, and the control of voltage deviation and frequency is mainly realized by the control of scheduling based on trend, be subjected to user's influence fluctuation less, do not research and analyse among the present invention.

1, the calculating of harmonic wave

According to the regulation in the GB/T14549-1993 standard, points of common connection bus harmonic voltage (phase voltage) limit value is as shown in table 1.

Table 1 points of common connection bus harmonic voltage (phase voltage) limit value

According to the regulation in the GB/T14549-1993 standard, the total allowable harmonic current that injects points of common connection is as shown in table 2 again.

Table 2 injects total allowable harmonic current of points of common connection

When the minimum capacity of short circuit at points of common connection place is different from the benchmark capacity of short circuit:

$I_h=\frac{S_{k1}}{S_{k2}}{I}_{\mathrm{hp}}$

In the formula: S _K1---the minimum capacity of short circuit of points of common connection, MVA

S _K2---benchmark capacity of short circuit, MVA

I _Hp---h subharmonic current permissible value under the benchmark capacity of short circuit situation, A

I _h---capacity of short circuit is S _K1The time h subharmonic current permissible value, A.

The allowable harmonic current that each user of same points of common connection injects to electrical network distributes at the protocol capacity of this some ratio with the power supply capacity of its points of common connection by this user.

I _hi＝I _h(S _i/S _t) ^1/α

In the formula: I _h---through the harmonic current limit value of capacity of short circuit conversion, A

S _i---i user's agreement electricity capacity, MVA

S _t---the power supply unit capacity of points of common connection, MVA

α---phase place stack coefficient is according to the harmonic number acquisition of tabling look-up.

2. the calculating of voltage fluctuation and flickering limit value

According to the regulation in the GB 12326-2000 standard, the voltage fluctuation limit value is as shown in table 3 again.

Table 3 voltage fluctuation limit value

The calculating of flickering limit value is as shown in table 4:

The flickering limit value of each electric pressure of table 4

The electric power system points of common connection, the short time flickering value P that causes by fluctuating load _StWith long-time flickering value P _LtShould satisfy the listed limit value of table 4.

The flickering limit value is according to the customer charge size, and its agreement electricity capacity accounts for the ratio and the system voltage classification of power supply capacity and does different regulations and processing.

(1) first order regulation.Satisfy regulation at the corresponding levels, can adjust, allow to insert electrical network without flickering.For 10kV, 35kV electric pressure user, first order limit value sees Table 5.

Table 510kV, 35kV user's first order limit value

For 110kV, 220kV electric pressure user, satisfy (Δ S/S _SC) _Max＜0.1%.

(2) second level regulation.Flickering carry-over factor T such as table 6 are listed between the different electric pressures.

Flickering carry-over factor between the different electric pressures of table 6

	??T HM
		Scope	??0.8～1.0
General value	??0.9

Being calculated as follows of user's flickering limit value:

For 10kV, 35kV unique user, at first obtain the whole loads that are connected to common bus and produce total limit value G of flickering

$G=\sqrt[3]{{L^3}_{\mathrm{MV}}-{T^3}_{\mathrm{HM}}{L^3}_{\mathrm{HV}}}$

With reference to table 4-2, L in the following formula _MVAnd L _HVBe respectively the flickering limit value (P of 10kV, 35kV _St=0.9, P _Lt=0.7) and the flickering limit value (P of 110kV, 220kV _St=0.8, P _Lt=0.6).

Then unique user flickering limit value is:

$E_{\mathrm{iMV}}=G\sqrt[3]{\frac{S_i}{S_{\mathrm{MV}}}\·\frac{1}{F_{\mathrm{MV}}}}$

In the formula: F _MVBe the simultaneity factor of fluctuating load, its representative value F _MV=0.2～0.3 (but must satisfy S _i/ F _MV≤ S _MV)

For 110kV, 220kV unique user, flickering limit value calculating formula is:

$E_{\mathrm{iHV}}=L_{\mathrm{HV}}\sqrt[3]{\frac{S_i}{S_{\mathrm{tHV}}}}$

L in the formula _HVFlickering limit value (P for 110kV, 220kV among the table 4-2 _St=0.8, P _Lt=0.6).S _iBe user's protocol capacity, S _THVFor the total power supply capacity of common bus, be the transformer capacity sum that connects on this bus for 110kV user, for 220kV user, need to consider the influence of transfer capacity.

(3) exempt flow process.

For some less user, the flickering limit value can be with reference to table 7.

Some less user's flickering limit value of table 7

??Eipst	??Ei?plt
		??0.35	??0.25

3. imbalance of three-phase voltage degree limit value calculates

Same, according to the regulation of GB/T 15543-1995 standard,, provide the limit value of imbalance of three-phase voltage degree in this algorithm for each electricity consumption client of application electricity consumption.Do not repeat them here.

In order more to understand technology contents of the present invention, especially exemplified by specific embodiment and cooperate appended graphic being described as follows.

Figure 1 shows that the device schematic diagram of distribution network electric energy quality monitoring management system.

As shown in Figure 1, this system adopts by server, Web server, the frame mode of the B/S (browser/server) that Web client constitutes.Distribution network electric energy quality monitoring management system 100 comprises Power Quality Detection administrative center 101, the communication server 102, SCADA system 103, central server 104, database server 105, Web server 106, and client 107a, 107b..., 107n.

Client 107a, 107b..., 107n is connected to central server 104 by Web server 106.Client 107a, 107b ..., 107n is by local area network (LAN) visit Web server 106, and Web server 106 is suitable for from client 107a, 107b ..., the 107n place obtains data.

Central server 104 electrically connects the communication server 102, database server 105 and Web server 106.Central server 104 is responsible for collecting index from Web server 106 and is calculated the assessment basic data and these basic datas are stored in database server 105.Then, central server 104 is on the basis of these data, and the model that provides according to previously described standard calculates, and after calculation task is finished the result also is stored in database server 105.Simultaneously, central server 104 is also issued result of calculation by Web server.

The communication server 102 electrically connects administrative center 101, central server 104 and SCADA system 103.Central server 104 is after finishing calculating, also result of calculation can be sent to administrative center 101 or SCADA system 103, for administrative center 101 or monitoring and control configuration (Supervisory Control And DataAcquisition, SCADA) 103 pairs of user power utilization situations of system assess, supervise, action such as improvement.

Figure 2 shows that the inputting interface schematic diagram of client.

The inputting interface 200 of client is positioned at the Web server issue page, and client can be opened by the IE browser.

Please refer to Fig. 1 and Fig. 2.Central server 104 calculates needs following initial data:

(1) mode of connection of power supply transformer station;

(2) capacity of supply transformer, parameter;

(3) capacity of short circuit of power supply substation bus bar;

(4) user's protocol capacity;

(5) Fu He feature etc.;

In these data, (1)～(3) belong to electrical network parameter, are provided by power supply enterprise, and the mode that imports by text deposits database server in, and (4)～(5) belong to user profile, pass through client 107a by the user, 107b..., 107n input.

The electrical network parameter input selects district 201 to comprise at least 4 fields: select transformer station's title, bus; The inlet highway capacity of short circuit; Input substation equipment parameter; Select the mode of connection.The mode of filling in of these fields can be selected by user's input or by drop-down menu.

The customer parameter input selects district 202 to comprise at least three fields: user's agreement electricity capacity; The background harmonics voltage and current; Select the affiliated combined entry of user.The mode of filling in of these fields can be selected by user's input or by drop-down menu.

After input was finished, program can begin to calculate, and result calculated shows in Calculation results output area 203, is saved to database server simultaneously and puts on record, browses for other client querys.Wherein, user's harmonic wave limit value is the harmonic wave limit value that distributes to the user, and the supervision and management of user's quality of power supply requires part to point out the type quality of power supply supervision and management flow process that load need carry out, for business references such as worker's inquiries.

Figure 3 shows that the method for monitoring and managing electrical energy quality of electric distribution network flow chart.

Please in conjunction with reference to figure 1 and Fig. 3.The method for monitoring and managing electrical energy quality of electric distribution network that the embodiment of the invention provides may further comprise the steps:

The user imports quality of power supply interference power load characterisitic parameter and system parameters S301, and in this step, the user can use client 107a shown in Figure 1,107b..., and 107n carries out the input of parameter.

At step S301, obtain to calculate after the required parameter, central server 104 carries out quality of power supply simulation calculation S302.In this step, central server 104 is to carry out computing according to the model that previously described standard provides.

Among the step S303, central server 104 compares the power quality index limit value that result of calculation and power supply enterprise provide.If result of calculation surpasses the power quality index limit value that power supply enterprise provides, then the power load of being supervised does not meet the requirement of index limit value; If result of calculation is no more than the power quality index limit value that power supply enterprise provides, then the power load of being supervised meets the requirement of index limit value.

If the power load of being supervised does not meet the requirement of index limit value, then carry out step S304, take quality of power supply corrective measure.Wherein quality of power supply corrective measure comprises:

(1), requires harmonic wave control scheme, resolution assessment etc. are examined, formulated to power supply plan for the user who belongs to non-linear pollutional load.

(2) requirement may produce the user installation electric energy quality monitor that the quality of power supply is polluted.

(3) out-of-limit user's time limit is administered etc.

If the power load of being supervised meets the requirement of index limit value, then carry out step S304, this power load is inserted electrical network.Follow-uply also can carry out power quality index actual measurement S305 to this power load.

If the power quality index results measured does not meet the requirement of index limit value, execution in step S304.

Though the present invention discloses as above with preferred embodiment, so it is not in order to limit the present invention.The persond having ordinary knowledge in the technical field of the present invention, without departing from the spirit and scope of the present invention, when being used for a variety of modifications and variations.Therefore, protection scope of the present invention is as the criterion when looking claims person of defining.

Claims (5)

1. a method for monitoring and managing electrical energy quality of electric distribution network is characterized in that, comprises the steps:

Input power load characterisitic parameter and system parameters;

Carry out quality of power supply simulation calculation;

Result of calculation and power quality index limit value are compared, judge whether result of calculation meets the index limit value; And

If the result of previous step takes quality of power supply corrective measure for not.

2. method for monitoring and managing electrical energy quality of electric distribution network according to claim 1 is characterized in that, also comprises when judging that result of calculation meets the index limit value, and this power load is inserted electrical network.

3. method for monitoring and managing electrical energy quality of electric distribution network according to claim 2 is characterized in that, also comprises after this power load inserts electrical network, and this power load is carried out the power quality index actual measurement; And

If results measured does not meet the requirement of index limit value, take quality of power supply corrective measure.

4. method for monitoring and managing electrical energy quality of electric distribution network according to claim 1 is characterized in that, wherein quality of power supply corrective measure comprises:

For the user who belongs to non-linear pollutional load, require harmonic wave control scheme, resolution assessment are examined, formulated to power supply plan;

Requirement may produce the user installation electric energy quality monitor that the quality of power supply is polluted; And

Out-of-limit user's time limit is administered.

5. method for monitoring and managing electrical energy quality of electric distribution network according to claim 1 is characterized in that, wherein this power quality index limit value is provided by power supply enterprise.

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