Group black start method and device of multi-machine parallel energy storage system and energy storage system

Abstract

The application provides a group black start method and device of a multi-machine parallel energy storage system and an energy storage system, and belongs to the field of energy storage. The method comprises the following steps: obtaining positive sequence feedback current average, negative sequence feedback current average and group black start given voltage of the energy storage system; performing current sharing control based on the positive sequence feedback current average and the negative sequence feedback current average to obtain positive sequence average current control quantity and negative sequence average current control quantity; performing positive sequence voltage control based on the positive sequence average current control quantity and the group black start given voltage to obtain given output current; performing current control based on the negative sequence average current control quantity and the given output current to determine a target control quantity; and controlling the corresponding energy storage converter to perform synchronous black start based on the target control quantity. The application can realize synchronous black start of each energy storage converter, and can save a large amount of time without starting in sequence, while ensuring that the power of the energy storage system can reach the expected output level.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage, and in particular to a group black start method and device for a multi-machine parallel energy storage system and an energy storage system. BACKGROUND

[0002] Black start refers to the process of restoring the operation of a power system without relying on external power sources after the power system is completely or partially powered off. Black start is an important means of emergency recovery of a power system, especially after a large-scale power outage or natural disaster, to ensure that critical facilities and services are restored to normal operation as soon as possible.

[0003] In related technologies, when a multi-machine system is black started, each machine is usually started in turn, i.e., after one machine is started, the next machine is started, and this process is repeated until all machines are started. However, this black start method takes a long time and the power output may not reach the expected level. SUMMARY

[0004] Embodiments of the present application provide a group black start method and device for a multi-machine parallel energy storage system and a controller to solve the problem that existing black start methods take a long time and the power output may not reach the expected level.

[0005] In a first aspect, embodiments of the present application provide a group black start method for a multi-machine parallel energy storage system. The energy storage system includes a plurality of parallel energy storage converters. The group black start method for the multi-machine parallel energy storage system is applied to a controller corresponding to each energy storage converter and includes:

[0006] obtaining a positive sequence feedback current average value, a negative sequence feedback current average value, and a group black start given voltage of the energy storage system;

[0007] performing current sharing control based on the positive sequence feedback current average value and the negative sequence feedback current average value to obtain a positive sequence average current control quantity and a negative sequence average current control quantity;

[0008] performing positive sequence voltage control based on the positive sequence average current control quantity and the group black start given voltage to obtain a given output current;

[0009] performing current control based on the negative sequence average current control quantity and the given output current to determine a target control quantity;

[0010] controlling the corresponding energy storage converter to perform synchronous black start based on the target control quantity to enable all energy storage converters of the energy storage system to perform synchronous black start.

[0011] In one possible implementation, performing positive sequence voltage control based on the positive sequence average current control quantity and the group black start given voltage to obtain a given output current includes:

[0012] Superimpose the positive sequence average current control amount on the group black start given voltage, and perform positive sequence voltage control to obtain a given output current.

[0013] In a possible implementation, based on the negative sequence average current control amount and the given output current, current control is performed to determine the target control amount, including:

[0014] The negative sequence average current control amount is subjected to negative sequence voltage control to obtain a first positive sequence control amount.

[0015] The first positive sequence control amount is superimposed on the given output current, and current control is performed to determine the target control amount.

[0016] In a possible implementation, based on the positive sequence feedback current average and the negative sequence feedback current average, current sharing control is performed to obtain the positive sequence average current control amount and the negative sequence average current control amount, including:

[0017] The positive sequence feedback current average is subjected to positive sequence current sharing control to obtain the positive sequence average current control amount.

[0018] The negative sequence feedback current average is subjected to negative sequence current sharing control to obtain the negative sequence average current control amount.

[0019] In a possible implementation, when there is a new energy storage converter integrated into the energy storage system during the group black start of the energy storage system, the control method for the current energy storage converters in the energy storage system is adopted to control the new energy storage converter, so that the new energy storage converter is kept in voltage synchronization and current sharing with the current energy storage converters in the energy storage system.

[0020] In a possible implementation, the positive sequence feedback current average is an average of the positive sequence feedback currents of the energy storage converters in the energy storage system, and the negative sequence feedback current average is an average of the negative sequence feedback currents of the energy storage converters in the energy storage system.

[0021] In a possible implementation, the corresponding energy storage converter is controlled to perform synchronous black start based on the target control amount, including:

[0022] The target control amount is subjected to drive control to determine a drive control signal.

[0023] The corresponding energy storage converter is controlled to perform synchronous black start based on the drive control signal.

[0024] In a second aspect, an embodiment of the present application provides a group black start device for a multi-machine parallel energy storage system. The energy storage system includes a plurality of parallel energy storage converters. The group black start device for the multi-machine parallel energy storage system is applied to a controller corresponding to each energy storage converter, and includes:

[0025] The acquisition module is configured to acquire a positive sequence feedback current average value, a negative sequence feedback current average value, and a group black start given voltage of the energy storage system.

[0026] The current sharing control module is configured to perform current sharing control based on the positive sequence feedback current average value and the negative sequence feedback current average value to obtain a positive sequence average current control quantity and a negative sequence average current control quantity.

[0027] The voltage control module is configured to perform positive sequence voltage control based on the positive sequence average current control quantity and the group black start given voltage to obtain a given output current.

[0028] The current control module is configured to perform current control based on the negative sequence average current control quantity and the given output current to determine a target control quantity.

[0029] The synchronous black start control module is configured to control a corresponding energy storage converter to perform synchronous black start based on the target control quantity, so that all energy storage converters of the energy storage system are synchronously black started.

[0030] In a third aspect, an embodiment of the present application provides a controller, including a processor and a memory, the memory is configured to store a computer program, and the processor is configured to invoke and run the computer program stored in the memory to execute the group black start method of the multi-machine parallel energy storage system as described in the first aspect or any possible implementation manner of the first aspect.

[0031] In a fourth aspect, an embodiment of the present application provides an energy storage system, including a plurality of parallel energy storage converters, and a controller corresponding to the energy storage converter as described in the third aspect; the energy storage converter is controlled by the corresponding controller.

[0032] In a fifth aspect, an embodiment of the present application provides a computer readable storage medium, the computer readable storage medium stores a computer program, and the computer program is executed by a processor to implement the steps of the group black start method of the multi-machine parallel energy storage system as described in the first aspect or any possible implementation manner of the first aspect.

[0033] The embodiment of the present application provides a group black start method, device and energy storage system of a multi-machine parallel energy storage system, the method performs current sharing control based on positive sequence feedback current average and negative sequence feedback current average, obtains positive sequence average current control quantity and negative sequence average current control quantity, then performs positive sequence voltage control based on the positive sequence average current control quantity and group black start given voltage, obtains given output current, then performs current control based on the negative sequence average current control quantity and the given output current, determines a target control quantity, and finally controls the corresponding energy storage converter based on the target control quantity to perform synchronous black start, so that all energy storage converters of the energy storage system can be synchronously black started, voltage synchronous control and current sharing control of each energy storage converter of the energy storage system can be realized, each energy storage converter can be synchronously black started without being started in turn, a large amount of time can be saved, and the power of the energy storage system can reach the expected output level. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0035] Figure 1 is an implementation flowchart of the group black start method of the multi-machine parallel energy storage system provided by the embodiment of the present application;

[0036] Figure 2 is a schematic diagram of the control loop corresponding to the group black start method of the multi-machine parallel energy storage system provided by the embodiment of the present application;

[0037] Figure 3 is a structural schematic diagram of the group black start device of the multi-machine parallel energy storage system provided by the embodiment of the present application;

[0038] Figure 4 is a schematic diagram of the controller provided by the embodiment of the present application. DETAILED DESCRIPTION

[0039] In the following description, specific details such as specific system structures, techniques, etc. are presented in order to thoroughly understand the embodiments of the present application, but it should be clear to those skilled in the art that the present application can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits and methods are omitted to avoid unnecessary details that hinder the description of the present application.

[0040] In order to make the objects, technical solutions and advantages of the present application clearer, the following will be described by specific embodiments with reference to the drawings.

[0041] Referring to Figure 1 , which shows an implementation flowchart of the group black start method of the multi-machine parallel energy storage system provided by the embodiment of the application. The multi-machine parallel energy storage system can be referred to as an energy storage system. The energy storage system includes a plurality of parallel energy storage converters (PCSs), and the number of energy storage converters in the energy storage system can be set according to actual requirements and is not specifically limited. Each energy storage converter in the energy storage system is controlled by the group black start method of the multi-machine parallel energy storage system described above to achieve group black start or synchronous black start.

[0042] The execution subject of the group black start method of the multi-machine parallel energy storage system described above can be a control device. In an implementation, the control device can be a general controller in the energy storage system, and each energy storage converter is controlled by the general controller. The general controller controls each energy storage converter by the method described above to achieve group black start. It should be noted that when the general controller controls each energy storage converter by the method described above, the required feedback parameters are the feedback parameters of the corresponding energy storage converter. For example, when the energy storage converter A is controlled, the feedback parameters required in the method are usually the feedback parameters of the energy storage converter A. The feedback parameters can include feedback current, feedback voltage, and other required feedback parameters. The feedback parameters can also be referred to as sampling parameters, which can be understood as the actual value of the parameter of the energy storage converter.

[0043] In another implementation, the control device can also be a controller corresponding to each energy storage converter in the energy storage system. Each controller controls the corresponding energy storage converter by the group black start method of the multi-machine parallel energy storage system described above to achieve group black start. That is, the method described above is applied to the controller corresponding to each energy storage converter in the energy storage system. It should be noted that when the controller controls the corresponding energy storage converter by the method described above, the required feedback parameters are the feedback parameters of the corresponding energy storage converter.

[0044] The following will be described in detail taking the control device as the controller corresponding to each energy storage converter in the energy storage system as an example.

[0045] Referring to Figure 1 , the method is described in detail as follows:

[0046] In S101, the positive sequence feedback current average value, the negative sequence feedback current average value, and the group black start given voltage of the energy storage system are obtained.

[0047] The positive sequence feedback current average value of the energy storage system is the average value of the positive sequence feedback current of each energy storage converter in the energy storage system; and the negative sequence feedback current average value of the energy storage system is the average value of the negative sequence feedback current of each energy storage converter in the energy storage system.

[0048] The embodiments of the present application do not make specific limitations on the acquisition means of the positive sequence feedback current and the negative sequence feedback current of each energy storage converter. After summing the positive sequence feedback currents of each energy storage converter, the positive sequence feedback current average value is obtained by dividing the number of energy storage converters. After summing the negative sequence feedback currents of each energy storage converter, the negative sequence feedback current average value is obtained by dividing the number of energy storage converters. The calculation process of the positive sequence feedback current average value and the negative sequence feedback current average value can be realized in the total controller, and then issued to the corresponding controller of each energy storage converter, or directly realized in the corresponding controller of each energy storage converter.

[0049] The group black start given voltage of the energy storage system can also be referred to as the group black start reference voltage of the energy storage system, which refers to the voltage that each energy storage converter in the energy storage system needs to reach during group black start. The group black start given voltage can include a given voltage amplitude and a given phase. The group black start given voltage of each energy storage converter in the energy storage system is the same, so that voltage synchronization control can be achieved.

[0050] In some possible implementations, when each energy storage converter of the energy storage system performs group black start, a slow start mode is adopted. Based on the slow start mode, the above-mentioned group black start given voltage of the energy storage system can be gradually increased from 0 until the voltage of the energy storage converter when it is working normally. That is, the group black start given voltage of each energy storage converter is increased synchronously.

[0051] The above-mentioned group black start given voltage of the energy storage system can be issued by the total controller to the corresponding controller of each energy storage converter. After the corresponding controller of each energy storage converter receives it for the first time, the above-mentioned method is started to be executed, and then each time a new group black start given voltage is received, the new group black start given voltage is used for control.

[0052] In some possible implementations, the S101 can include:

[0053] When the group black start instruction is received, the positive sequence feedback current average value, the negative sequence feedback current average value and the group black start given voltage of the energy storage system are acquired to achieve synchronous black start.

[0054] In S102, based on the positive sequence feedback current average value and the negative sequence feedback current average value, flow equalization control is performed to obtain a positive sequence average current control quantity and a negative sequence average current control quantity.

[0055] The embodiment of the present application can perform current sharing control based on the positive sequence feedback current average value and the negative sequence feedback current average value, so that the positive sequence average current control quantity and the negative sequence average current control quantity corresponding to the energy storage converter can be obtained. The positive sequence average current control quantity can be used for positive sequence voltage control. The negative sequence average current control quantity can be transformed into positive sequence timing and then current control is performed.

[0056] The embodiment of the present application does not make specific limitation on the specific implementation means of performing current sharing control based on the positive sequence feedback current average value and the negative sequence feedback current average value to obtain the positive sequence average current control quantity and the negative sequence average current control quantity, and any implementable means can be used.

[0057] In S103, the positive sequence voltage control is performed based on the positive sequence average current control quantity and the group black start given voltage, and the given output current is obtained.

[0058] The group black start given voltage can be used as the given output voltage of each energy storage converter, and the positive sequence voltage control is performed in combination with the positive sequence average current control quantity to obtain the given output current of the corresponding energy storage converter. Since the group black start given voltage includes the given voltage amplitude and the given phase, the same group black start given voltage is used for control, and the voltage amplitude and the voltage phase of each energy storage converter can be synchronized.

[0059] In S104, the current control is performed based on the negative sequence average current control quantity and the given output current, and the target control quantity is determined.

[0060] The embodiment of the present application can perform current control according to the current sharing control quantity and the given output current, so that the target control quantity of the corresponding energy storage converter is obtained. The target control quantity can be used to generate the corresponding drive control signal for controlling the corresponding energy storage converter.

[0061] The embodiment of the present application does not make specific limitation on the specific implementation means of performing current control based on the negative sequence average current control quantity and the given output current to determine the target control quantity, and any implementable means can be used.

[0062] In S105, the corresponding energy storage converter is controlled to perform synchronous black start based on the target control quantity, so that all energy storage converters of the energy storage system are synchronously black started.

[0063] The embodiment of the present application controls the corresponding energy storage converter based on the target control quantity. Since each controller of each energy storage converter of the energy storage system synchronously performs the method provided by the embodiment of the present application to realize the synchronous black start control of the corresponding energy storage converter, all energy storage converters of the energy storage system can be synchronously black started.

[0064] The embodiment of the application performs current sharing control based on the positive sequence feedback current average value and the negative sequence feedback current average value, obtains a positive sequence average current control quantity and a negative sequence average current control quantity, then performs positive sequence voltage control based on the positive sequence average current control quantity and a group black start given voltage, obtains a given output current, then performs current control based on the negative sequence average current control quantity and the given output current, determines a target control quantity, and finally controls the corresponding energy storage converter to perform synchronous black start based on the target control quantity, so that all energy storage converters of the energy storage system can be synchronously black started, voltage synchronous control and current sharing control of each energy storage converter of the energy storage system can be realized, each energy storage converter can be synchronously black started without being started in sequence, a large amount of time can be saved, and the power of the energy storage system can reach the expected output level.

[0065] In some embodiments, S102 can include:

[0066] The positive sequence feedback current average value is subjected to positive sequence current sharing control to obtain a positive sequence average current control quantity.

[0067] The negative sequence feedback current average value is subjected to negative sequence current sharing control to obtain a negative sequence average current control quantity.

[0068] Referring to the control loop shown in Figure 2 The positive and negative sequence feedback current average values include the positive sequence feedback current average value and the negative sequence feedback current average value.

[0069] The positive sequence feedback current average value is subjected to positive sequence current sharing control to obtain a positive sequence average current control quantity. Specifically, the positive sequence feedback current of the corresponding energy storage converter is obtained, a first difference between the positive sequence feedback current average value and the positive sequence feedback current is calculated, and the first difference is input into a first preset proportional integral controller to obtain the positive sequence average current control quantity. The related parameters in the first preset proportional integral controller have been pre-set and can be set according to actual needs.

[0070] The negative sequence feedback current average value is subjected to negative sequence current sharing control to obtain a negative sequence average current control quantity. Specifically, the negative sequence feedback current of the corresponding energy storage converter is obtained, a second difference between the negative sequence feedback current average value and the negative sequence feedback current is calculated, and the second difference is input into a second preset proportional integral controller to obtain the negative sequence average current control quantity. The related parameters in the second preset proportional integral controller have been pre-set and can be set according to actual needs.

[0071] In some embodiments, S103 can include:

[0072] The positive sequence average current control quantity is superimposed on the group black start given voltage, and positive sequence voltage control is performed to obtain a given output current.

[0073] Referring to Figure 2 The positive sequence average current control quantity can be superimposed on the group black start given voltage, i.e., the positive sequence average current control quantity and the group black start given voltage are summed to obtain a superimposed given voltage of the energy storage converter. Based on the superimposed given voltage, positive sequence voltage control can be performed to obtain a given output current of the energy storage converter.

[0074] Exemplarily, a feedback voltage corresponding to the energy storage converter can be obtained, and the feedback voltage is a feedback output voltage; a third difference between the superimposed given voltage and the feedback voltage is calculated, and the third difference is input into a third preset proportional integral controller to obtain the given output current. The related parameters in the third preset proportional integral controller are pre-set and can be set according to actual needs.

[0075] In some possible implementations, the output end of the parallel energy storage converter can be connected to a transformer, so that three-phase three-wire to three-phase four-wire conversion can be realized. Based on the structure, the group black start given voltage can be determined according to a given output voltage of the transformer. Specifically, a feedback voltage of the transformer is obtained, a fourth difference between the given output voltage of the transformer and the feedback voltage of the transformer is calculated, and the fourth difference is input into a fourth preset proportional integral controller to obtain the group black start given voltage. The related parameters in the fourth preset proportional integral controller are pre-set and can be set according to actual needs.

[0076] In some possible implementations, the positive sequence average current control quantity, the voltage DC component control quantity and the current DC component control quantity can all be superimposed on the group black start given voltage, and positive sequence voltage control is performed to obtain the given output current.

[0077] In some embodiments, S104 can include:

[0078] The negative sequence average current control quantity is subjected to negative sequence voltage control to obtain a first positive sequence control quantity;

[0079] The first positive sequence control quantity is superimposed on the given output current, and current control is performed to determine a target control quantity.

[0080] The negative sequence average current control quantity is controlled by the negative sequence voltage to obtain the first positive sequence control quantity, which can include: obtaining the negative sequence feedback voltage of the corresponding energy storage converter, calculating the fifth difference value between the negative sequence average current control quantity of the corresponding energy storage converter and the negative sequence feedback voltage of the corresponding energy storage converter, inputting the fifth difference value into the fifth preset proportional integral controller to obtain the first negative sequence control quantity of the corresponding energy storage converter, and transforming the first negative sequence control quantity to the positive sequence time sequence to obtain the first positive sequence control quantity of the corresponding energy storage converter. The related parameters in the fifth preset proportional integral controller are pre-set and can be set according to actual needs.

[0081] Referring to Figure 2 The first positive sequence control quantity can be superimposed on the given output current of the corresponding energy storage converter, that is, the first positive sequence control quantity and the given output current are summed to obtain the superimposed given output current of the corresponding energy storage converter. Based on the superimposed given output current, current control is performed to obtain the target control quantity of the corresponding energy storage converter.

[0082] Exemplarily, the feedback output current of the corresponding energy storage converter can be obtained; the sixth difference value between the superimposed given output current and the feedback output current is calculated, and the sixth difference value is input into the sixth preset proportional integral controller to obtain the target control quantity. The related parameters in the sixth preset proportional integral controller are pre-set and can be set according to actual needs.

[0083] The above-mentioned current sharing control method can obtain the positive sequence average current control quantity and the negative sequence average current control quantity by the above-mentioned current sharing control, superimpose the positive sequence average current control quantity on the group black start given voltage to perform positive sequence voltage control, superimpose the first positive sequence control quantity obtained by controlling the negative sequence average current control quantity by the negative sequence voltage on the given output current to perform current control, so that the current sharing control of each energy storage converter can be realized.

[0084] In some embodiments, when there is a new energy storage converter integrated into the energy storage system during the group black start of the energy storage system, the control method of the current energy storage converters in the energy storage system is used to control the new energy storage converter, so that the new energy storage converter is kept in voltage synchronization and current sharing with the current energy storage converters in the energy storage system.

[0085] In the embodiments of the present application, when the energy storage system is performing group black start, a new energy storage converter can be incorporated into the energy storage system at any time during the process of black start and participate in the group black start. The new incorporated energy storage converter adopts the same group black start given voltage and the same control method, so that the new incorporated energy storage converter is under the same closed-loop control quantity, ensures that the output voltage is synchronized with other energy storage converters, and after the same current sharing control, ensures that the new incorporated energy storage converter and other energy storage converters share the current, thereby realizing the voltage synchronization and current sharing of all energy storage converters in the energy storage system.

[0086] In some embodiments, in the above S105, the corresponding energy storage converter is controlled to perform synchronous black start based on the target control quantity, including:

[0087] The target control quantity is driven and controlled to determine a drive control signal;

[0088] Based on the drive control signal, the corresponding energy storage converter is controlled to perform synchronous black start.

[0089] The above driving and controlling of the target control quantity to determine the drive control signal can include: summing the above target control quantity and the feedback output voltage of the corresponding energy storage converter, and normalizing the summed voltage to obtain a target duty cycle, and generating the drive control signal based on the target duty cycle.

[0090] Based on the drive control signal, the corresponding energy storage converter is controlled.

[0091] It should be understood that the size of the serial number of each step in the above embodiments does not mean the order of execution, and the execution order of each process should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0092] Figure 3 The structure of the group black start device of the multi-machine parallel energy storage system provided by the embodiments of the present application is shown, only the parts related to the embodiments of the present application are shown for convenience, and the details are as follows:

[0093] The energy storage system includes a plurality of parallel energy storage converters, and the group black start device of the multi-machine parallel energy storage system is applied to the controller corresponding to each energy storage converter in the energy storage system, as shown in Figure 3 The group black start device 30 of the multi-machine parallel energy storage system includes an acquisition module 31, a current sharing control module 32, a voltage control module 33, a current control module 34, and a synchronous black start control module.

[0094] The acquisition module 31 is used to acquire the positive sequence feedback current average value, the negative sequence feedback current average value and the group black start given voltage of the energy storage system;

[0095] The current-sharing control module 32 is configured to perform current-sharing control based on the positive-sequence feedback current average value and the negative-sequence feedback current average value, to obtain a positive-sequence average current control quantity and a negative-sequence average current control quantity;

[0096] The voltage control module 33 is configured to perform positive-sequence voltage control based on the positive-sequence average current control quantity and a group black-start given voltage, to obtain a given output current;

[0097] The current control module 34 is configured to perform current control based on the negative-sequence average current control quantity and the given output current, to determine a target control quantity;

[0098] The synchronous black-start control module 35 is configured to control the corresponding energy storage converter to perform synchronous black-start based on the target control quantity, so that all the energy storage converters of the energy storage system are synchronously black-started.

[0099] In a possible implementation, the voltage control module 33 is specifically configured to:

[0100] superimpose the positive-sequence average current control quantity on the group black-start given voltage, and perform positive-sequence voltage control to obtain the given output current.

[0101] In a possible implementation, the current control module 34 is specifically configured to:

[0102] perform negative-sequence voltage control on the negative-sequence average current control quantity to obtain a first positive-sequence control quantity;

[0103] superimpose the first positive-sequence control quantity on the given output current, and perform current control to determine the target control quantity.

[0104] In a possible implementation, the current-sharing control module 32 is specifically configured to:

[0105] perform positive-sequence current-sharing control on the positive-sequence feedback current average value to obtain the positive-sequence average current control quantity;

[0106] perform negative-sequence current-sharing control on the negative-sequence feedback current average value to obtain the negative-sequence average current control quantity.

[0107] In a possible implementation, when there is a new energy storage converter incorporated into the energy storage system during the group black-start of the energy storage system, the control method for the current energy storage converters in the energy storage system is adopted to control the new energy storage converter, so that the new energy storage converter is kept in voltage synchronization and current sharing with the current energy storage converters in the energy storage system.

[0108] In a possible implementation, the positive-sequence feedback current average value is an average value of the positive-sequence feedback currents of the energy storage converters in the energy storage system; and the negative-sequence feedback current average value is an average value of the negative-sequence feedback currents of the energy storage converters in the energy storage system.

[0109] In one possible implementation, the synchronous black-start control module 35 is specifically used for:

[0110] Drive the target control quantity to determine the drive control signal;

[0111] Based on the drive control signal, the corresponding energy storage converter is controlled to perform synchronous black start.

[0112] Figure 4 This is a schematic diagram of the controller provided in an embodiment of the present invention. Figure 4 As shown, the controller 4 in this embodiment includes a processor 40 and a memory 41. The memory 41 stores a computer program 42, and the processor 40 calls and runs the computer program 42 stored in the memory 41 to execute the steps in the above embodiments of the group black start method for various multi-machine parallel energy storage systems, for example... Figure 1 S101 to S105 are shown. Alternatively, the processor 40 is used to call and run the computer program 42 stored in the memory 41 to implement the functions of each module / unit in the above-described device embodiments, for example... Figure 3 The functions of each module are shown.

[0113] For example, the computer program 42 can be divided into one or more modules / units, which are stored in the memory 41 and executed by the processor 40 to complete the present invention. The one or more modules / units can be a series of computer program instruction segments capable of performing a specific function, which describe the execution process of the computer program 42 in the controller 4. For example, the computer program 42 can be divided into... Figure 3 The modules shown.

[0114] The controller 4 may include, but is not limited to, a processor 40 and a memory 41. Those skilled in the art will understand that... Figure 4 This is merely an example of controller 4 and does not constitute a limitation on controller 4. It may include more or fewer components than shown, or combine certain components, or different components. For example, the controller may also include input / output devices, network access devices, buses, etc. For example, the controller may also include the aforementioned DMS and OMS, etc.

[0115] The processor 40 can be a central processing unit (CPU), and can also be other general-purpose processors, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor.

[0116] The memory 41 can be an internal storage unit of the controller 4, such as a hard disk or a memory of the controller 4. The memory 41 can also be an external storage device of the controller 4, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. Further, the memory 41 can include both an internal storage unit and an external storage device of the controller 4. The memory 41 is used to store the computer program and other programs and data required by the controller. The memory 41 can also be used to temporarily store data that has been output or is to be output.

[0117] Corresponding to the above controller, the embodiment of the present application further provides an energy storage system, comprising a plurality of energy storage converters connected in parallel, and a controller as described above corresponding to the energy storage converter; the energy storage converter is controlled by the corresponding controller.

[0118] The energy storage system is described in the foregoing embodiments, and will not be described again.

[0119] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the above-mentioned division of each functional unit and module is exemplified, and in actual application, the above-mentioned functions can be completed by different functional units and modules according to needs, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiment can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be realized in the form of hardware or software. In addition, the specific names of each functional unit and module are only for easy distinction, and do not limit the protection scope of the present application. The specific working process of the units and modules in the above system can refer to the corresponding process in the foregoing method embodiments, which will not be repeated here.

[0120] In the above embodiments, the description of each embodiment has its own emphasis, and the parts not described or recorded in detail in a certain embodiment can be referred to the related description of other embodiments.

[0121] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be realized in electronic hardware or a combination of computer software and electronic hardware. Whether the functions are executed in hardware or software depends on the specific application and design constraints of the technical solution. A person skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0122] In the embodiments provided by the present application, it should be understood that the disclosed devices / controllers and methods can be implemented in other ways. For example, the above-described device / controller embodiments are only schematic. The division of the modules or units is only a logical function division, and there can be another division manner in actual implementation. For example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some interface, device or unit, and can be electrical, mechanical or in other forms.

[0123] The units described as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, that is, they can be located in one place, or can be distributed on a plurality of network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0124] In addition, each function unit in each embodiment of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software function unit.

[0125] The integrated module / unit, if realized in the form of a software function unit and sold or used as an independent product, can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the above-mentioned embodiment methods can also be completed by a computer program instructing related hardware, and the computer program can be stored in a computer-readable storage medium. When the processor executes the computer program, the steps of each of the above-mentioned multi-machine parallel energy storage system group black start method embodiments can be implemented. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or some intermediate forms, etc. The computer-readable medium can include any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the contents included in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction, for example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0126] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of each embodiment of the present application, and should be included in the protection scope of the present application.

Claims

1. A group black start method of a multi-machine parallel energy storage system, characterized in that, The energy storage system comprises a plurality of parallel energy storage converters, and the method is applied to a controller corresponding to each energy storage converter, and comprises the following steps of: obtaining positive sequence feedback current average value, negative sequence feedback current average value and group black start given voltage of the energy storage system; based on the positive sequence feedback current average value and the negative sequence feedback current average value, current sharing control is performed to obtain positive sequence average current control quantity and negative sequence average current control quantity; wherein the positive sequence feedback current of the corresponding energy storage converter is obtained, the first difference value between the positive sequence feedback current average value and the positive sequence feedback current is calculated, and the first difference value is input into the first preset proportional integral controller to obtain the positive sequence average current control quantity; the negative sequence feedback current of the corresponding energy storage converter is obtained, the second difference value between the negative sequence feedback current average value and the negative sequence feedback current is calculated, and the second difference value is input into the second preset proportional integral controller to obtain the negative sequence average current control quantity; based on the positive sequence average current control quantity and the group black start given voltage, positive sequence voltage control is performed to obtain given output current; based on the negative sequence average current control quantity and the given output current, current control is performed to determine target control quantity; based on the target control quantity, synchronous black start of the corresponding energy storage converter is controlled to enable synchronous black start of all energy storage converters of the energy storage system.

2. The method of black start of a group of multi-parallel energy storage systems according to claim 1, characterized in that, The positive sequence voltage control based on the positive sequence average current control quantity and the group black start given voltage to obtain the given output current comprises the following steps of: the positive sequence average current control quantity is superimposed on the group black start given voltage, and positive sequence voltage control is performed to obtain the given output current.

3. The method of black start of a group of multi-parallel energy storage systems of claim 1, wherein, The current control based on the negative sequence average current control quantity and the given output current to determine the target control quantity comprises the following steps of: the negative sequence average current control quantity is subjected to negative sequence voltage control to obtain first positive sequence control quantity; the first positive sequence control quantity is superimposed on the given output current, and current control is performed to determine the target control quantity.

4. The method of black start of a group of multi-parallel energy storage systems of claim 1, wherein, The current sharing control based on the positive sequence feedback current average value and the negative sequence feedback current average value to obtain the positive sequence average current control quantity and the negative sequence average current control quantity comprises the following steps of: the positive sequence feedback current average value is subjected to positive sequence current sharing control to obtain the positive sequence average current control quantity; the negative sequence feedback current average value is subjected to negative sequence current sharing control to obtain the negative sequence average current control quantity.

5. The method of black start of a group of multi-parallel energy storage systems of claim 1, wherein, When a new energy storage converter is incorporated into the energy storage system during group black start of the energy storage system, the control method for the current energy storage converters in the energy storage system is adopted to control the new energy storage converter, so that the new energy storage converter is kept in voltage synchronization and current sharing with the current energy storage converters in the energy storage system.

6. The method of black start of a group of multi-parallel energy storage systems according to any one of claims 1 to 5, characterized in that, The positive sequence feedback current average value is the average value of the positive sequence feedback current of each energy storage converter in the energy storage system; and the negative sequence feedback current average value is the average value of the negative sequence feedback current of each energy storage converter in the energy storage system.

7. The method of black start of a group of multi-parallel energy storage systems according to any one of claims 1 to 5, characterized in that, The synchronous black start of the corresponding energy storage converter based on the target control quantity comprises the following steps of: drive control is performed on the target control quantity to determine a drive control signal; based on the drive control signal, the corresponding energy storage converter is controlled to perform synchronous black start.

8. A group black start device for a plurality of energy storage systems connected in parallel, characterized in that, The energy storage system includes a plurality of parallel energy storage converters, and the device is applied to a controller corresponding to each energy storage converter, comprising: an acquisition module for acquiring a positive sequence feedback current average value, a negative sequence feedback current average value and a group black start given voltage of the energy storage system; a current sharing control module for performing current sharing control based on the positive sequence feedback current average value and the negative sequence feedback current average value to obtain a positive sequence average current control quantity and a negative sequence average current control quantity; wherein the positive sequence feedback current of the corresponding energy storage converter is acquired, the first difference value between the positive sequence feedback current average value and the positive sequence feedback current is calculated, and the first difference value is input into a first preset proportional integral controller to obtain the positive sequence average current control quantity; the negative sequence feedback current of the corresponding energy storage converter is acquired, the second difference value between the negative sequence feedback current average value and the negative sequence feedback current is calculated, and the second difference value is input into a second preset proportional integral controller to obtain the negative sequence average current control quantity; a voltage control module for performing positive sequence voltage control based on the positive sequence average current control quantity and the group black start given voltage to obtain a given output current; a current control module for performing current control based on the negative sequence average current control quantity and the given output current to determine a target control quantity; a synchronous black start control module for controlling the corresponding energy storage converter to perform synchronous black start based on the target control quantity, so that all energy storage converters of the energy storage system are synchronously black started.

9. A controller characterized by comprising: comprising a memory and a processor, the memory being used to store a computer program, and the processor being used to call and run the computer program stored in the memory to execute the group black start method of the multi-machine parallel energy storage system according to any one of claims 1 to 7.

10. An energy storage system characterized by, comprising a plurality of parallel energy storage converters, and a controller corresponding to the energy storage converter according to claim 9; the energy storage converter is controlled by the corresponding controller.

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