KR102630314B1 - AC-DC converter employing high efficiency load sharing with parrallel structure - Google Patents

Abstract

The embodiment relates to a high-efficiency load sharing parallel structure AC-DC converter for a special vehicle equipped with a single-phase alternator.
Specifically, this AC-DC converter is a high-efficiency converter with a load sharing method in a parallel structure. When multiple converter modules in a parallel structure are in a normal state, the AC-DC power conversion operation is performed as a whole from these converter modules, DC power is supplied to shared loads.
And, when one or more converter modules among these converter modules are in an abnormal state, the AC-DC conversion operation is partially performed by the remaining converter modules in addition to the converter module in the abnormal state.
In addition, in the case of partial conversion in this way, the output of the output module is divided into 1/3, etc., and a load sharing type output technology is applied, thereby maintaining the minimum output.
Therefore, through this, the operability of the operating equipment in use is maintained with minimal output under extreme operating conditions, such as in vehicles. Therefore, if there is no countermeasure for various failure situations, it becomes impossible to operate the equipment in extreme situations. By overcoming these conditions, AC input is maintained as a converter for vehicles.

Description

AC-DC converter employing high efficiency load sharing with parallel structure for special vehicles equipped with single-phase alternator

The content disclosed in this specification relates to an AC-DC converter, and more specifically, to a special vehicle converter that receives AC power from an external source, converts it to DC power, and supplies power to the vehicle while operating a vehicle.

Unless otherwise indicated herein, the material described in this section is not prior art to the claims of this application, and is not admitted to be prior art by inclusion in this section.

Generally, an AC-DC converter is a device that converts external AC power into DC power and supplies it to a load, and is used in vehicles, such as refrigerated trucks.

For example, three-phase AC-DC converters are widely used in many fields. Thanks to the technology development of electric vehicles, interest in the power quality of vehicle power conversion devices is growing, and at the same time, responsibility for technology development to curb global warming is increasing.

Meanwhile, it is estimated that most converter failures during PWM control of power devices, which are the core of power conversion devices, are caused by failures of switching devices such as IGBT and SiC. Failure of switching elements can be broadly divided into short circuit failure and open circuit failure. For example, when a short circuit failure occurs, power is generally cut off by a protection circuit such as a breaker or fuse, but if not, not only is the switching element destroyed, but it also causes serious damage to surrounding elements.

On the other hand, if an open circuit failure occurs, the system does not immediately stop but continues to operate with reduced performance. At this time, the current contains many harmonic components, and each phase not only causes unbalance, but also causes fluctuation of the system frequency component in the generated DC terminal voltage. If this abnormal operation continues, there is a possibility that malfunctions of other elements caused by fatigue accumulated due to unstable operation may lead to secondary failures in the converter system, load, or system. Therefore, when a failure of a switching element occurs in a converter system, it is necessary to quickly determine the cause of the failure and take action to resolve it. And, when a failure occurs in the converter system, finding the cause takes a lot of time and money, and becomes more difficult as the system becomes more complex.

In addition to these points, the AC-DC converter creates an environment in which the equipment can no longer be operated if the converter breaks down while the equipment is in operation.

The prior art literature against this background is limited to the extent of the patent documents below.

(Patent Document 1) KR101235182 B1

For reference, the technology in Patent Document 1 relates to a failure diagnosis device for AC-DC converters, which monitors the current value of three phases by changing the current vector position angle of two phases to accurately detect a failed phase during operation of the converter system. do.

The disclosed content maintains the operability of operating equipment in use with minimum output under extreme operating conditions such as vehicles, and maintains AC input to operate the equipment in various failures or extreme situations, while maintaining a power control module in a high-efficiency load sharing parallel structure. We aim to provide an AC-DC converter.

The high-efficiency load-sharing parallel structure AC-DC converter for a special vehicle equipped with a single-phase alternator according to the embodiment is a high-efficiency load-sharing converter implemented with three power control modules with a total capacity of 3 kW each, with a capacity of 1 kW each, and has a parallel structure. When multiple converter modules are in a normal state, the AC-DC power conversion operation from the converter modules is operated with the total output, so DC power is supplied to the shared load.

When one or more converter modules among these converter modules are in an abnormal state, the AC-DC conversion operation is partially performed by the remaining converter modules in addition to the converter module in the abnormal state. In addition, in the case of partial conversion in this way, the output of the output module is divided into 1/3, etc., and a load sharing type output technology is applied, thereby maintaining the minimum output.

According to embodiments, the operability of operational equipment in use is maintained with minimal output under extreme operating conditions, such as in vehicles. Therefore, if there is no countermeasure for various failure situations, it becomes impossible to operate the equipment in extreme situations. By overcoming these conditions, a converter for a vehicle that maintains AC input is provided.

1 is a diagram conceptually illustrating a high-efficiency load sharing parallel structure AC-DC converter for a special vehicle equipped with a single-phase alternator according to an embodiment.
Figure 2 is a diagram showing the overall system to which a high-efficiency load sharing parallel structure AC-DC converter is applied for a special vehicle equipped with a single-phase alternator according to an embodiment.
Figure 3 is a block diagram showing the configuration of a high-efficiency load sharing parallel structure AC-DC converter for a special vehicle equipped with a single-phase alternator according to an embodiment.
Figure 4 is a functional configuration diagram of the AC-DC converter of Figure 3
Figure 5 is a flow chart sequentially showing the operation of the high-efficiency load sharing parallel structure AC-DC converter of a special vehicle equipped with a single-phase alternator according to an embodiment.

Figure 1 is a diagram conceptually illustrating a high-efficiency load sharing parallel structure AC-DC converter for a special vehicle equipped with a single-phase alternator according to an embodiment.

As shown in FIG. 1, the basic feature of the high-efficiency load sharing parallel structure AC-DC converter according to one embodiment is operability under extreme operating conditions. In other words, existing converters can no longer be used when a failure occurs during operation, but one embodiment is characterized by limiting the use of only the failed module. For reference, these loads include fans and heaters.

Specifically, the AC-DC converter according to one embodiment is a high-efficiency converter with a load sharing method in a parallel structure. When multiple converter modules in a parallel structure are in a normal state, the AC-DC power conversion operation is performed from these converter modules. To perform the entire operation, DC power is supplied to the shared load.

And, when one or more converter modules among these converter modules are in an abnormal state, the AC-DC conversion operation is partially performed by the remaining converter modules in addition to the converter module in the abnormal state.

In addition, in the case of partial conversion like this, the output of the output module is divided into 1/3, etc., and a load sharing type output technology is applied, thereby maintaining the minimum output.

For example, when there are three output modules, the output is limited to 2/3 when there is one or more modules, and the output is limited to 1/3 when there are two or more modules.

Additionally, in this case, this AC-DC converter performs a power monitoring function while operating the parallel structure converter, specifically, power control modules 1, 2, and 3, and monitors the DC output status. , In addition, it displays AC input power status and load amount.

Therefore, through this, the AC-DC converter according to one embodiment maintains the operability of the operating equipment in use with minimum output under extreme operating conditions. Therefore, if there is no countermeasure for various failure situations, it becomes impossible to operate the equipment in extreme situations. By overcoming these conditions, AC input is maintained as a converter for vehicles.

Additionally, when the AC-DC converter of this embodiment performs monitoring in this way, it also monitors the load and monitors the load that is driven by receiving DC power from the converter itself.

Specifically, when this AC-DC converter supplies DC power to shared loads, it determines the presence or absence of an abnormality from each load for each load depending on whether an abnormal signal is input from the load.

As a result of the determination, if there is an abnormality in the load, the corresponding lamp in the display unit is turned on to alarm the abnormal state of the load.

Additionally, the loads at this time are, for example, fans, heaters, and lower-order controllers, and are connected to various actuators and management devices through the lower-order controllers and remotely managed through external communication (CAN).

Figure 2 is a diagram illustrating the overall system to which a high-efficiency load sharing parallel structure AC-DC converter is applied for a special vehicle equipped with a single-phase alternator according to an embodiment.

As shown in FIG. 2, the system of one embodiment includes an AC-DC converter 100 and a load according to one embodiment.

The AC-DC converter 100 maintains the operability of operational equipment with minimum output under extreme operating conditions, such as in vehicles, and maintains AC input even in a malfunction situation. So, for this purpose, the AC-DC converter 100 is composed of a high-efficiency converter with a parallel structure and load sharing method. So, in this case, when multiple converter modules are in a normal state, that is, in normal times, the AC-DC power conversion operation is performed entirely from these converter modules to supply DC power to the shared load. And, when an abnormal state occurs in such a converter module, the AC-DC conversion operation is partially performed by the remaining converter modules in addition to the converter module in the abnormal state. In addition, in the case of partial conversion like this, the minimum output is maintained by dividing the output of the output module into 1/3, etc. and applying load sharing output technology. Additionally, when this AC-DC converter supplies DC power to shared loads, it determines the presence or absence of an abnormality from each load for each load depending on whether an abnormal signal is input from the load. As a result of the determination, if there is an abnormality in the load, the corresponding lamp in the display unit is turned on to alarm the abnormal state of the load. So, this allows the shared load to be monitored from the converter itself.

When DC power is generated in the AC-DC converter 100, the load is driven by receiving DC power from the AC-DC converter 100. At this time, multiple loads receive DC power in a shared manner. Provides high efficiency. And, at this time, each load transmits and receives signals to and from the AC-DC converter 100 so that the AC-DC converter 100 can report any abnormality. For example, these loads include fans and heaters, and may further include various actuators and management devices through sub-controllers.

Figure 3 is a block diagram showing the configuration of a high-efficiency load sharing parallel AC-DC converter for a special vehicle equipped with a single-phase alternator according to an embodiment.

As shown in FIG. 3, the high-efficiency load sharing parallel structure AC-DC converter 100 of one embodiment includes a plurality of converter modules 101 and a control motherboard 102.

Additionally, the AC-DC converter 100 according to one embodiment includes a DC output switch 103, an EMI filter 104, and a display unit 105.

*First, as before, when driving a load, the plurality of converter modules 101 perform AC-DC power conversion from an external AC power source and supply DC power for driving to the load. In this state, according to one embodiment, it is made in the form of a module as a load sharing type in a parallel structure, and when AC-DC power conversion is performed in this way, the AC input is maintained even in a failure situation.

The control motherboard 102 controls the AC-DC power conversion operation by the plurality of converter modules 101. Specifically, according to one embodiment, the control motherboard 102 operates as follows. That is, a) First, when controlling the AC-DC power conversion operation, the presence of a module error and the number of module errors are determined from the plurality of converter modules 101 as a result of comparison between the current DC power value and the setting standard DC power value. do. b) As a result of the determination, when the plurality of converter modules 101 are in a normal state, the AC-DC power conversion operation is performed as a whole from the plurality of converter modules 101 to supply DC power to the shared load. c-1) In this state, when one or more converter modules among the plurality of converter modules 101 are in an abnormal state, the AC-DC conversion operation is partially performed by the remaining converter modules in addition to the converter module in the abnormal state. c-2) Also, in this case, that is, when the AC-DC conversion operation is partially performed, the output from the remaining converter modules is reduced differently in proportion to the number of modules, thereby limiting the output and reducing DC power. Supply to shared load.

As described above, when performing partial DC power conversion to AC power, the DC output switch 103 limits the output of the output module to apply the output technology of the load sharing method, thereby providing the minimum output. maintain For example, when there are three output modules, the DC output switch 103 divides and limits the output to 2/3 when there is more than one module, and to 1/3 when there are more than two modules.

When external AC power is input, the EMI filter 104 removes electrical noise from the AC power and supplies stable power to the AC-DC converter 100.

The display unit 105 performs a power monitoring function on the lamp while operating the converter in this parallel structure, displays the DC output status, and also displays the AC input power status and load amount. At this time, the lamp is provided for each of these various functions. In addition, when this DC power is supplied to the shared load, the display unit 105 determines the presence or absence of an abnormality from each load for each load, as described above in the control motherboard 102, and the determination result, load If there is an abnormality, the corresponding lamp is turned on to alarm the abnormal condition of the load.

Meanwhile, additionally, when the AC-DC converter 100 converts DC power in this way, it stores DC power from the configuration below and supplies it to each load in a load sharing method, thereby increasing high efficiency and operating effectively.

To this end, the AC-DC converter 100 further includes a storage battery module (not shown) that stores the DC power.

In this case, the control motherboard 102 monitors the stored voltage of the storage battery module (not shown), sets the number of converter modules correspondingly for each level to which the current voltage belongs, and configures the converter modules differently for each stored voltage. It runs properly.

In addition, in this case, when driving the converter module, the control motherboard 102 controls the AC-DC power conversion operation of the converter module differently in response to the current number of converter modules and the number of shared loads.

In addition, the control motherboard 102 may further include the following components.

a) That is, when driving the converter module, a map table that converts the mapping relationship between the request command value of the converter module and the set reference output operation value is registered in advance for a plurality of different stored voltage levels.

b) Therefore, the AC-DC power conversion operation of the converter module is controlled differently according to the voltage level currently stored by the map table, so the converter module is driven according to the stored voltage.

In this case, the control motherboard 102 provides, for example, information that converts the mapping relationship between the request command value of the converter module and the reference output operation value for each number of different shared loads and shared load types in the map table. Includes.

FIG. 4 is a functional configuration diagram of the AC-DC converter of FIG. 3.

As shown in FIG. 4, the AC-DC converter 100 according to one embodiment represents the functional configuration of a vehicle converter and is largely made of a converter module 101 and a control motherboard 102.

In this case, the converter module 101 consists of an AC input, a two-phase interleaved bridgeless PFC converter, a dc-dc ZVS PSFB, and a synchronous rectifier.

In addition, the control motherboard 102 is composed of a converter parallel structure MCU, and this MCU includes a plurality of gate drivers.

Figure 5 is a flow chart sequentially showing the operation of a high-efficiency load sharing parallel structure AC-DC converter of a special vehicle equipped with a single-phase alternator according to an embodiment (see Figure 3).

As shown in FIG. 5, when the high-efficiency load sharing parallel structure AC-DC converter of one embodiment first receives external AC power from the control motherboard, it determines whether the module is defective from a plurality of converter modules in a parallel structure. The number of abnormalities is determined as a result of comparison between the current DC power value and the preset reference DC power value (S501).

As a result of the determination, when the plurality of converter modules are in a normal state (S502), the AC-DC power conversion operation is performed as a whole from the plurality of converter modules (S503), and DC power is supplied to the shared load (S504). .

On the other hand, when one or more converter modules among the plurality of converter modules are in an abnormal state, the AC-DC conversion operation is partially performed by the remaining converter modules in addition to the converter module in the abnormal state.

Also, when the AC-DC conversion operation is partially performed, the output from the remaining converter modules is reduced differently in proportion to the number of modules (S505), thereby limiting the output and directing the DC power to the shared load. supply.

Therefore, through this, the AC-DC converter according to one embodiment maintains the operability of the operating equipment in use with minimum output under extreme operating conditions. Therefore, if there is no countermeasure for various failure situations, it becomes impossible to operate the equipment in extreme situations. By overcoming these conditions, AC input is maintained as a converter for vehicles.

As described above, one embodiment is a high-efficiency converter with a load sharing method in a parallel structure. When a plurality of converter modules in a parallel structure are in a normal state, the overall AC-DC power conversion operation is performed from these converter modules, Supply power to shared loads.

And, when one or more converter modules among these converter modules are in an abnormal state, the AC-DC conversion operation is partially performed by the remaining converter modules in addition to the converter module in the abnormal state.

In addition, when converting only parts like this, the output of the output module is divided into 1/3, etc., and the output technology of the load sharing method is applied to maintain the minimum output.

Accordingly, through this, one embodiment maintains the operability of the operating equipment in use with minimal output under extreme operating conditions, such as in vehicles. Therefore, if there is no countermeasure for various failure situations, it becomes impossible to operate the equipment in extreme situations. By overcoming these conditions, AC input is maintained as a converter for vehicles.

100: AC-DC converter 101: Converter module
102: Motherboard for control 103: DC output switch
104: EMI filter 105: display unit

Claims (1)

In the high-efficiency load sharing parallel structure AC-DC converter for special vehicles equipped with a single-phase alternator that converts external AC power to AC-DC and supplies DC power to the load,
The AC-DC converter is
Multiple converter modules in parallel load sharing type;
A control motherboard that controls AC-DC conversion by the plurality of converter modules; and
A display unit including a lamp indicating the output state of the DC power converted by the control motherboard and a lamp indicating whether the load is abnormal,

How the control motherboard controls AC-DC conversion is
A first step of determining whether an abnormality exists by comparing the current DC power value of the plurality of converter modules with a preset reference DC power value,
In the first step, when the plurality of converter modules are in a normal state, a second step of performing an entire AC-DC conversion operation from the plurality of converter modules to supply DC power to the shared load;
In the first step, if one or more of the plurality of converter modules is in an abnormal state, an AC-DC conversion operation is performed with the remaining converter modules in addition to the converter module in the abnormal state to supply DC power to the shared load, and the abnormality A third step of limiting DC power output according to the number of converter modules in the state;
In the third step, when there are three converter modules, if one converter module is in an abnormal state, the DC power output is limited to 2/3, and if two converter modules are in an abnormal state, the DC power output is limited to 1/3,

The method for the control motherboard to drive the plurality of converter modules is
The number of converter modules is set correspondingly for each voltage level of the storage battery module that stores the DC power, and a mapping relationship between the request command value of the converter module and the preset reference output operation value is established for a plurality of different shared loads and shared load types. Registering a map table that converts the number of converter modules for each voltage level of the storage battery module and controlling the plurality of converter modules based on the map table; A special vehicle equipped with a single-phase alternator, characterized in that High-efficiency load sharing parallel structure AC-DC converter.