Cooperative control test method and system suitable for sodium ion energy storage equipment

Abstract

The invention provides a cooperative control test method and system suitable for sodium ion energy storage equipment, and relates to the technical field of energy storage equipment. When a high-power test is carried out on tested energy storage equipment in a test mode, auxiliary energy storage equipment can be used for compensating power overflowing out of the power grid capability, so that the test efficiency is improved; and aiming at the tested energy storage equipment and the auxiliary energy storage equipment which are of a string structure, the influence of the operation state of the PCS is considered in the testing process, the combined control of each PCS in the tested energy storage equipment and the auxiliary energy storage equipment is realized, and the combined control mode can avoid the impact on a power grid caused by the fault of a single PCS or a small number of PCS, so that the reliability of the system is improved. Therefore, under the condition that the power provided by the power grid is smaller than the power required by the test, the high-power test of the energy storage equipment is realized, and meanwhile, the damage of a single PCS fault to the power grid is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage equipment, and in particular to a collaborative control test method and system suitable for sodium ion energy storage equipment. Background Art

[0002] In the energy storage system, EMS (Energy Management System) is a set of energy management systems suitable for low-voltage distribution systems that are secondary developed according to user needs and in compliance with the standard specifications of the distribution system. It has the characteristics of strong professionalism, high degree of automation, ease of use, high performance, and high reliability. Through telemetry and remote control, loads can be reasonably allocated, optimized operation can be achieved, and electricity can be effectively saved. There are records of peak and valley electricity consumption, which provides the necessary conditions for energy management. At the same time, electricity is measured by item according to the electricity consumption of open sockets, power electricity, air conditioning electricity, and special electricity consumption, providing a basis for energy energy conservation audits of enterprises and institutions.

[0003] The energy storage equipment of the energy storage system needs to be tested at full power to verify whether the quality of the energy storage equipment is qualified. However, during the full power test, the power required by the energy storage equipment under test will be greater than the power that the distribution network can provide. For example, the distribution network can only provide 150kW of power, and the energy storage equipment needs to support 1.25MW of power during testing. How to achieve high-power testing of energy storage equipment when the power provided by the grid is less than the power required for the test is an urgent problem to be solved. Summary of the invention

[0004] The object of the present invention is to provide a collaborative control test method and system suitable for sodium ion energy storage equipment, so as to realize high-power testing of sodium ion energy storage equipment and the like when the power provided by the power grid is less than the power required for the test, while reducing the damage to the power grid caused by a single PCS (Power Conversion System, energy storage converter) failure.

[0005] In a first aspect, an embodiment of the present invention provides a collaborative control test method applicable to a sodium ion energy storage device, which is applied to a control device, wherein the control device is connected to a tested energy storage device and an auxiliary energy storage device respectively, wherein both the tested energy storage device and the auxiliary energy storage device adopt a string architecture in which battery clusters are connected to a plurality of independently controlled PCSs, and the AC output terminals of the tested energy storage device and the auxiliary energy storage device are connected in parallel to the same target AC bus of the power grid; the method comprises:

[0006] In response to the test start instruction, a test mode of the energy storage device under test is obtained; wherein the test mode includes a charging mode or a discharging mode;

[0007] During the test, the first PCS operating status information corresponding to the energy storage device under test and the second PCS operating status information corresponding to the auxiliary energy storage device are obtained in real time, and based on the first PCS operating status information, the second PCS operating status information and the test mode, each PCS in the energy storage device under test and the auxiliary energy storage device is controlled to charge and discharge through the power grid; wherein the charging and discharging state of the energy storage device under test is opposite to that of the auxiliary energy storage device, and the auxiliary energy storage device is used to charge and discharge through the power grid to compensate for the output power of the power grid.

[0008] Further, based on the first PCS operation status information, the second PCS operation status information and the test mode, each PCS in the energy storage device under test and the auxiliary energy storage device is controlled to charge and discharge through the power grid, including:

[0009] Based on the first PCS operation status information, the current output power of each PCS in the energy storage device under test, and the test mode, calculate the current total output power of the energy storage device under test;

[0010] Determine whether the absolute value of the current total output power of the energy storage device under test is less than the total rated power of the energy storage device under test, and obtain a first determination result;

[0011] If the first judgment result is yes, the current total output power of the auxiliary energy storage device is calculated based on the second PCS operation status information, the current output power of each PCS in the auxiliary energy storage device, and the test mode;

[0012] Based on the current total output power of the energy storage device under test and the current total output power of the auxiliary energy storage device, the output power of each target PCS in the energy storage device under test and the auxiliary energy storage device is dynamically increased; wherein the target PCS is a running PCS;

[0013] Re-execute the step of determining whether the absolute value of the current total output power of the energy storage device under test is less than the total rated power of the energy storage device under test to obtain a first determination result until the energy storage device under test operates at full power;

[0014] Among them, when the test mode is the charging mode, the energy storage device under test is charged through the power grid, the current total output power of the energy storage device under test is a negative value, the auxiliary energy storage device is discharged through the power grid, and the current total output power of the auxiliary energy storage device is a positive value; when the test mode is the discharging mode, the energy storage device under test is discharged through the power grid, the current total output power of the energy storage device under test is a positive value, the auxiliary energy storage device is charged through the power grid, and the current total output power of the auxiliary energy storage device is a negative value.

[0015] Further, based on the first PCS operation status information, the current output power of each PCS in the energy storage device under test, and the test mode, the current total output power of the energy storage device under test is calculated, including:

[0016] The current total output power P1 of the energy storage device under test is calculated by the following formula:

[0017]

[0018] Among them, P 1i is the current output power of the i-th PCS in the energy storage device under test, E 1i is the power coefficient corresponding to the operating state of the i-th PCS in the energy storage device under test, n is the number of PCSs in the energy storage device under test, the power coefficient corresponding to the PCS running in the charging state is -1, the power coefficient corresponding to the PCS running in the discharging state is 1, and the power coefficient corresponding to the PCS not running is 0.

[0019] Furthermore, based on the current total output power of the energy storage device under test and the current total output power of the auxiliary energy storage device, the output power of each target PCS in the energy storage device under test and the auxiliary energy storage device is dynamically increased, including:

[0020] Increasing the corresponding unit power of each target PCS in the energy storage device under test and the auxiliary energy storage device, and updating the current total output power of the energy storage device under test and the current total output power of the auxiliary energy storage device;

[0021] Determine whether the absolute value of the current total output power of the energy storage device under test is greater than the absolute value of the current total output power of the auxiliary energy storage device, and obtain a second determination result;

[0022] Based on the second judgment result, the corresponding unit power of each target PCS in the energy storage device under test or the auxiliary energy storage device is increased.

[0023] Furthermore, each PCS in the energy storage device under test and the auxiliary energy storage device is configured with redundant power, and the above method further includes:

[0024] If the first judgment result is no, determining that the energy storage device under test is operating at full power;

[0025] During full power operation of the energy storage device under test, output power is dynamically allocated to each target PCS in the energy storage device under test based on the first PCS operating status information, and output power is dynamically allocated to each target PCS in the auxiliary energy storage device based on the second PCS operating status information.

[0026] Furthermore, after the energy storage device under test is running at full power, the method further includes:

[0027] In response to the test end event, the output power of each target PCS in the energy storage device under test and the auxiliary energy storage device is dynamically reduced until the current total output power of the energy storage device under test and the current total output power of the auxiliary energy storage device are both 0; wherein the test end event includes a first event corresponding to the test end instruction input by the user, or a second event corresponding to the full-power operation time reaching a preset time.

[0028] Furthermore, the control device is also connected to a dynamic load energy storage device, and the AC output terminal of the dynamic load energy storage device is connected to the target AC bus of the power grid; based on the first PCS operating status information, the second PCS operating status information and the test mode, each PCS in the energy storage device under test and the auxiliary energy storage device is controlled to charge and discharge through the power grid, including:

[0029] Based on the first PCS operating status information, the second PCS operating status information and the test mode, each PCS in the energy storage device under test and the auxiliary energy storage device, as well as the dynamic load energy storage device are controlled to charge and discharge through the power grid.

[0030] Further, in the process of controlling each PCS in the energy storage device under test and the auxiliary energy storage device, and the dynamic load energy storage device to charge and discharge through the power grid based on the first PCS operating status information, the second PCS operating status information and the test mode, the following formula is satisfied:

[0031]

[0032] Among them, P 1i is the current output power of the i-th PCS in the energy storage device under test, E 1i is the power coefficient corresponding to the operating state of the i-th PCS in the energy storage device under test, n is the number of PCSs in the energy storage device under test, P 2i is the current output power of the i-th PCS in the auxiliary energy storage device, E 2i is the power coefficient corresponding to the operating state of the i-th PCS in the auxiliary energy storage device, m is the number of PCS in the auxiliary energy storage device, the power coefficient corresponding to the PCS in operation in the charging state is -1, the power coefficient corresponding to the PCS in operation in the discharging state is 1, and the power coefficient corresponding to the PCS not in operation is 0, P rated is the total rated power of the energy storage device under test, P limi is the power limit at the grid access interface where the target AC busbar of the grid is located, P load It is used to store dynamic load energy of dynamic load energy storage equipment.

[0033] In a second aspect, an embodiment of the present invention further provides a control device, including a memory and a processor, wherein the memory stores a computer program that can be run on the processor, and when the processor executes the computer program, the collaborative control test method applicable to the sodium ion energy storage device of the first aspect is implemented.

[0034] In a third aspect, an embodiment of the present invention further provides a collaborative control test system suitable for a sodium ion energy storage device, comprising the control device of the second aspect, and also comprising a tested energy storage device and an auxiliary energy storage device respectively connected to the control device.

[0035] In a collaborative control test method and system for sodium ion energy storage devices provided by an embodiment of the present invention, the method is applied to a control device, the control device is respectively connected to a tested energy storage device and an auxiliary energy storage device, the tested energy storage device and the auxiliary energy storage device both adopt a string-type architecture in which battery clusters are respectively connected to a plurality of independently controlled PCSs, and the AC output terminals of the tested energy storage device and the auxiliary energy storage device are connected in parallel to the same target AC bus of the power grid; the method comprises: in response to a test start instruction, obtaining a test mode of the tested energy storage device; wherein the test mode comprises a charging mode or a discharging mode; during the test, obtaining in real time the first PCS operating status information corresponding to the tested energy storage device and the second PCS operating status information corresponding to the auxiliary energy storage device, and based on the first PCS operating status information, the second PCS operating status information and the test mode, controlling the tested energy storage device and the auxiliary energy storage device to charge and discharge through the power grid; wherein the charging and discharging state of the tested energy storage device is opposite to the charging and discharging state of the auxiliary energy storage device, and the auxiliary energy storage device is used to charge and discharge through the power grid to compensate for the output power of the power grid. In this way, when conducting high-power tests in the test mode of the energy storage device under test, the auxiliary energy storage device can be used to compensate for the power overflowing the grid capacity. In addition, for the energy storage device under test and the auxiliary energy storage device in the string architecture, the influence of the PCS operating status is considered during the test process, and the joint control of each PCS in the energy storage device under test and the auxiliary energy storage device is realized. This joint control method can avoid the impact of a single or a small number of PCS failures on the grid, thereby realizing high-power testing of the energy storage device when the power that the grid can provide is less than the power required for the test, while reducing the damage to the grid caused by a single PCS failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 A schematic diagram of the structure of a collaborative control test system applicable to a sodium ion energy storage device provided in an embodiment of the present invention;

[0038] Figure 2 A schematic flow chart of a collaborative control test method applicable to a sodium ion energy storage device provided in an embodiment of the present invention;

[0039] Figure 3 A schematic diagram of a power control flow of a collaborative control test system in a charging mode provided by an embodiment of the present invention;

[0040] Figure 4 A schematic diagram of a power control flow of a collaborative control test system in a discharge mode provided by an embodiment of the present invention;

[0041] Figure 5 A schematic diagram of the structure of a control device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0042] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] A pair-to-pair test method can be used to use auxiliary energy storage devices to provide power compensation for the test of the energy storage device under test; in the pair-to-pair test, one energy storage device is charged and the other energy storage device is discharged. The energy storage device under test and the auxiliary energy storage device are usually managed for charging and discharging through a PCS. Considering that when two PCSs are tested in a pair-to-pair test, when one PCS fails, the output power of the corresponding energy storage device under test or the auxiliary energy storage device will drop off a cliff, which has a great impact on the power grid and is likely to damage the power grid equipment. Based on this, the collaborative control test method and system for sodium ion energy storage devices provided in the embodiment of the present invention solves the problem of system crash caused by a PCS failure through group control pair-to-pair in string mode.

[0044] The embodiment of the present invention provides a collaborative control test system suitable for sodium ion energy storage equipment, see Figure 1 A structural schematic diagram of a collaborative control test system suitable for sodium ion energy storage devices is shown, the system comprising a control device 100, and also comprising a tested energy storage device 101 and an auxiliary energy storage device 102 respectively connected to the control device 100.

[0045] The energy storage device 101 under test and the auxiliary energy storage device 102 are both charged and discharged through the power grid. Specifically, the energy storage device 101 under test and the auxiliary energy storage device 102 both adopt a string-type architecture in which battery clusters are connected to multiple independently controlled PCSs, and the AC output terminals of the PCSs in the energy storage device 101 under test and the auxiliary energy storage device 102 are connected in parallel to the same target AC bus of the power grid, such as Figure 1 The AC bus where M (i.e., the energy meter) is located. The control device 100 is used to control the charge and discharge state and output power of each PCS of the energy storage device 101 under test and the auxiliary energy storage device 102 by executing a preset coordinated control test method applicable to sodium ion energy storage devices, so as to achieve full power test of the energy storage device 101 under test mode when the power that the power grid can provide is less than the power required for the test; wherein, the test mode can be a charging mode or a discharging mode; in different test modes, the charge and discharge states of the energy storage device 101 under test and the auxiliary energy storage device 102 are different.

[0046] The energy storage device 101 under test is an energy storage device that needs to be tested by power test (such as constant power operation test) or power test, and the power required by the energy storage device 101 under test is greater than the power that the power grid can provide. It should be noted that this embodiment does not limit the test type. In specific implementation, the energy storage device 101 under test can be tested at full power, that is, the maximum power required for the test is equal to the rated maximum power (that is, the total rated power) of the energy storage device 101 under test; or the energy storage device 101 under test can be tested at non-full power, that is, the maximum power required for the test is lower than the rated maximum power of the energy storage device 101 under test. The auxiliary energy storage device 102 is used to provide power compensation to the power grid during the test of the energy storage device 101 under test to assist in the test of the energy storage device 101 under test. The energy storage device 101 under test and the auxiliary energy storage device 102 can be energy storage devices of the same model or different models. This embodiment does not limit the specific energy storage device.

[0047] In the energy storage device 101 under test and the auxiliary energy storage device 102, one PCS is used to control the charging and discharging process of a Na battery (i.e., sodium battery) to achieve AC-DC conversion. The number of PCSs in the energy storage device 101 under test and the number of PCSs in the auxiliary energy storage device 102 can be the same or different. For example, Figure 1 The energy storage device 101 under test and the auxiliary energy storage device 102 each include 44 PCSs. Preferably, the number of PCSs in the auxiliary energy storage device 102 is not less than the number of PCSs in the energy storage device 101 under test to improve system stability. It should be noted that the above system is not only applicable to sodium ion energy storage devices, but also to other energy storage devices, such as lithium ion energy storage devices, etc., that is, Figure 1The Na batteries in the battery can be replaced by other types of batteries.

[0048] The auxiliary energy storage device 102 adopts a battery cluster connected to independently controlled PCSs, and a string-type architecture with parallel convergence control on the AC side of multiple PCSs. This can achieve power and energy redundancy of the auxiliary energy storage device 102. When a single cluster failure (such as a single battery failure and / or a single PCS failure) occurs, the operation sequence can be independently cut off to improve system stability.

[0049] Due to the existence of charging and discharging losses of the energy storage device, the total energy of the auxiliary energy storage device 102 can be higher than 120% of the total energy of the energy storage device 101 under test (that is, the total energy of the auxiliary energy storage device 102 is 1.2 times higher than the total energy of the energy storage device 101 under test) to avoid test interruption due to the auxiliary energy storage device 102 reaching the operating boundary conditions in advance (such as the battery is fully charged or discharged in advance).

[0050] Optionally, the above-mentioned collaborative control test system also has a fault redundancy adjustment function, that is, each PCS in the energy storage device 101 under test and the auxiliary energy storage device 102 is configured with redundant power. Figure 1 In the system, all 88 PCSs are configured with redundant power (e.g. rated power is 30kW and redundant power is 50kW). When one or several PCSs have problems, other normal PCSs can quickly supplement the output power of the faulty PCSs, thereby ensuring the output power and system stability.

[0051] Optionally, to further improve system stability, such as Figure 1 As shown, the system further includes a dynamic load energy storage device 103 , which is connected to the control device 100 , and an AC output terminal of the dynamic load energy storage device 103 is connected to a target AC bus of the power grid.

[0052] The dynamic load energy storage device 103 and the auxiliary energy storage device 102 jointly provide power compensation for the test of the energy storage device 101 under test. The dynamic load energy storage device 103 can provide fault redundancy adjustment for the auxiliary energy storage device 102, further improving the system stability. The dynamic load energy storage device 103 can use a lithium battery energy storage device. It should be noted that this embodiment does not limit this, and the dynamic load energy storage device 103 can also use other types of energy storage devices.

[0053] like Figure 1As shown, the communication between the control device 100 and the energy storage device 101 to be tested, the auxiliary energy storage device 102 and the dynamic load energy storage device 103 can be, but is not limited to, using the ModbusTCP communication protocol. The ModbusTCP communication protocol is a Modbus variant based on the TCP / IP protocol, which allows the Modbus protocol to run on an Ethernet network, allowing devices to exchange data through an IP network. This communication method is relatively low cost.

[0054] In one possible implementation, Figure 1 As shown, the collaborative control test system in this embodiment adopts a joint control mode of 88 sets of PCS+dynamic load energy storage devices. Through internal energy flow, the mutual control and energy flow between each PCS of the energy storage device 101 under test and each PCS of the auxiliary energy storage device 102 are guaranteed, and the power control steps of the energy storage device 101 under test and the auxiliary energy storage device 102 are kept consistent; all energy storage devices transfer energy under the joint action of the control device 100; through the group control strategy (dynamic increase and dynamic decrease of group control PCS power, and group control of single PCS failure), the power of the energy storage device 101 under test is guaranteed to be constant, and the auxiliary power energy flows dynamically to the energy storage device 101 under test, so as to ensure that the distribution network operates at rated power to prevent overage, take as little power from the distribution network as possible, and save test costs.

[0055] The above energy storage equipment can be used for capacity reduction on the grid side (i.e., capacity expansion and charging on the user side) and for the adjustment of demand electricity charges on the user side. For example, when the on-site load is large and exceeds the rated power of the transformer, the energy storage equipment can be discharged to reduce the power obtained from the grid and achieve capacity reduction on the grid side. The above energy storage equipment can also realize a sponge-type energy storage system, such as in charging piles and other aspects.

[0056] To facilitate understanding of this embodiment, the collaborative control test method applicable to the sodium ion energy storage device performed by the above-mentioned control device 100 is described in detail below.

[0057] The embodiment of the present invention provides a collaborative control test method applicable to sodium ion energy storage devices. The method is applied to the control device 100 in the collaborative control test system applicable to sodium ion energy storage devices, that is, the method can be executed by the control device 100. The method is not only applicable to the test of sodium ion energy storage devices, but also to the test of other energy storage devices (such as lithium ion energy storage devices, etc.). Figure 2 A flow chart of a collaborative control test method applicable to a sodium ion energy storage device is shown, and the method mainly includes the following steps S210 to S220:

[0058] Step S210, in response to a test start instruction, obtaining a test mode of the energy storage device under test.

[0059] The test mode includes a charging mode or a discharging mode.

[0060] In a possible implementation, the control device has a display screen, and the user can select a test mode (charging mode or discharging mode) and a test type (such as a power test or a power test) through a test interface displayed on the display screen, and click a start icon (such as an OK button) to issue a test start instruction to start the test. The control device can parse the test mode and test type from the test start instruction, and control the energy storage device under test and the auxiliary energy storage device based on the test mode and test type.

[0061] Step S220, during the test, the first PCS operating status information corresponding to the energy storage device under test and the second PCS operating status information corresponding to the auxiliary energy storage device are obtained in real time, and based on the first PCS operating status information, the second PCS operating status information and the test mode, each PCS in the energy storage device under test and the auxiliary energy storage device is controlled to charge and discharge through the power grid; wherein the charge and discharge state of the energy storage device under test is opposite to the charge and discharge state of the auxiliary energy storage device, and the auxiliary energy storage device is used to charge and discharge through the power grid to compensate for the output power of the power grid.

[0062] The above-mentioned first PCS operating status information includes the operating status of each PCS in the energy storage device under test, and the second PCS operating status information includes the operating status of each PCS in the auxiliary energy storage device, wherein the operating status of the PCS can include two categories: operating and not operating, and not operating can include two situations: shutdown and failure.

[0063] In order to test high-power energy storage equipment under the condition of limited grid power, the sum of the output power of the auxiliary energy storage equipment and the output power of the grid shall not be lower than the output power of the energy storage equipment under test.

[0064] Optionally, the output power of the energy storage device under test matches the output power of the auxiliary energy storage device, that is, the output power of the auxiliary energy storage device can offset the power overflowing from the output power of the energy storage device under test to the power grid, that is, the output power of the auxiliary energy storage device (here refers to the absolute value) is within the preset range corresponding to the difference between the output power of the energy storage device under test and the maximum power provided by the power grid. The preset range can be set according to actual needs and is not limited here. For example, the lower limit of the preset range is the difference between the output power of the energy storage device under test and the maximum power provided by the power grid, and the upper limit of the preset range is the sum of the output power of the energy storage device under test and the maximum power provided by the power grid. In this embodiment, the energy storage device under test actively adjusts, and the auxiliary energy storage device cooperates passively; some cooperation strategies are predefined, and the user can select the required cooperation strategy through the interface, such as selecting the subsequent unit power size.

[0065] During the charging and discharging process, the power of the energy storage device under test and the auxiliary energy storage device can be controlled by a power ladder increase method, and the power overflowing from the power grid capacity of the energy storage device under test can be offset by the auxiliary energy storage device during the increase process until the energy storage device under test runs at full power. This can improve the stability of power control and reduce the impact on the power grid gateway power; the gateway power is the output power at the grid access interface where the target AC bus of the grid is located, that is, the output power of the grid at the interface where the collaborative control test system is connected to the grid; when the energy storage device is charged through the grid, the gateway power will increase, and when the energy storage device is discharged through the grid, the gateway power will decrease.

[0066] Based on this, in some possible embodiments, the above step S220 may include the following sub-steps:

[0067] Sub-step 221, based on the first PCS operation status information, the current output power of each PCS in the energy storage device under test and the test mode, calculate the current total output power of the energy storage device under test. Then, sub-step 222 is executed.

[0068] Sub-step 222, determine whether the absolute value of the current total output power of the energy storage device under test is less than the total rated power of the energy storage device under test, and obtain a first determination result. Then, execute sub-step 223 (if the first determination result is yes) or sub-step 225 (if the first determination result is no).

[0069] Sub-step 223, if the first judgment result is yes, the current total output power of the auxiliary energy storage device is calculated based on the second PCS operation status information, the current output power of each PCS in the auxiliary energy storage device, and the test mode. Then, sub-step 224 is executed.

[0070] Sub-step 224, based on the current total output power of the energy storage device under test and the current total output power of the auxiliary energy storage device, dynamically increase the output power of each target PCS in the energy storage device under test and the auxiliary energy storage device; wherein the target PCS is the running PCS. Then re-execute sub-step 222 until the energy storage device under test is running at full power.

[0071] Sub-step 225: If the first judgment result is no, it is determined that the energy storage device under test is running at full power. Then, sub-step 226 is executed or sub-step 227 is directly executed.

[0072] Sub-step 226, during the full power operation of the energy storage device under test, dynamically allocate the output power of each target PCS in the energy storage device under test based on the first PCS operation status information, and dynamically allocate the output power of each target PCS in the auxiliary energy storage device based on the second PCS operation status information. Wherein, each PCS in the energy storage device under test and the auxiliary energy storage device is configured with redundant power. Then execute sub-step 227.

[0073] Sub-step 227, in response to the test end event, dynamically reduce the output power of each target PCS in the energy storage device under test and the auxiliary energy storage device until the current total output power of the energy storage device under test and the current total output power of the auxiliary energy storage device are both 0; wherein the test end event includes a first event corresponding to the test end instruction input by the user, or a second event corresponding to the full-power operation time reaching a preset time.

[0074] Among them, when the test mode is the charging mode, the energy storage device under test is charged through the power grid, the current total output power of the energy storage device under test is a negative value, the auxiliary energy storage device is discharged through the power grid, and the current total output power of the auxiliary energy storage device is a positive value; when the test mode is the discharging mode, the energy storage device under test is discharged through the power grid, the current total output power of the energy storage device under test is a positive value, the auxiliary energy storage device is charged through the power grid, and the current total output power of the auxiliary energy storage device is a negative value.

[0075] For the above sub-step 221, in a possible implementation, the current total output power P1 of the energy storage device under test can be calculated by the following formula:

[0076]

[0077] Among them, P 1i is the current output power of the i-th PCS in the energy storage device under test, E 1i is the power coefficient corresponding to the operating state of the i-th PCS in the energy storage device under test, n is the number of PCSs in the energy storage device under test, the power coefficient corresponding to the PCS running in the charging state is -1, the power coefficient corresponding to the PCS running in the discharging state is 1, and the power coefficient corresponding to the PCS not running is 0.

[0078] Correspondingly, for the above sub-step 223, the current total output power P2 of the auxiliary energy storage device can be calculated by the following formula:

[0079]

[0080] Among them, P 2i is the current output power of the i-th PCS in the auxiliary energy storage device, E 2iis the power coefficient corresponding to the operating state of the i-th PCS in the auxiliary energy storage device, m is the number of PCS in the auxiliary energy storage device, the power coefficient corresponding to the PCS in operation in the charging state is -1, the power coefficient corresponding to the PCS in operation in the discharging state is 1, and the power coefficient corresponding to the PCS not in operation is 0.

[0081] For the above-mentioned sub-step 224, in a possible implementation, the corresponding unit power of each target PCS in the energy storage device under test and the auxiliary energy storage device can be increased first, and the current total output power of the energy storage device under test and the current total output power of the auxiliary energy storage device can be updated; after the update, it is determined whether the absolute value of the current total output power of the energy storage device under test is greater than the absolute value of the current total output power of the auxiliary energy storage device to obtain a second judgment result; based on the second judgment result, the corresponding unit power of each target PCS in the energy storage device under test or the auxiliary energy storage device is increased.

[0082] The unit power corresponding to the energy storage device under test and the unit power corresponding to the auxiliary energy storage device can be set according to actual needs, and the two can be the same or different. Preferably, the unit power corresponding to the energy storage device under test is greater than or equal to the unit power corresponding to the auxiliary energy storage device. Among them, the larger the unit power, the shorter the time required for the energy storage device under test to reach the full power state, but the greater the fluctuation of the gateway power of the power grid; conversely, the smaller the unit power, the longer the time required for the energy storage device under test to reach the full power state, but the smaller the fluctuation of the gateway power of the power grid. When the second judgment result is yes, only the corresponding unit power of each target PCS in the auxiliary energy storage device is increased; when the second judgment result is no, only the corresponding unit power of each target PCS in the energy storage device under test is increased.

[0083] For the above-mentioned sub-step 226, in a possible implementation, the first PCS operating status information and the second PCS operating status information are monitored in real time to see whether they change; when the first PCS operating status information changes, based on the current number of target PCSs in the energy storage device under test and the total rated power of the energy storage device under test, the first target power corresponding to the single target PCS is calculated, and each target PCS in the energy storage device under test is controlled to operate at the first target power; when the second PCS operating status information changes, based on the current number of target PCSs in the auxiliary energy storage device and the total rated power of the energy storage device under test, the second target power corresponding to the single target PCS is calculated, and each target PCS in the auxiliary energy storage device is controlled to operate at the second target power.

[0084] For the above sub-step 227, the dynamic decreasing process is opposite to the above dynamic increasing process. In specific implementation, it can be first determined whether the absolute value of the current total output power of the energy storage device under test is greater than 0 to obtain a third judgment result; if the third judgment result is yes, the corresponding unit power of each target PCS in the energy storage device under test and the auxiliary energy storage device is decreased, and the current total output power of the energy storage device under test and the current total output power of the auxiliary energy storage device are updated; it is determined whether the absolute value of the current total output power of the energy storage device under test is less than the absolute value of the current total output power of the auxiliary energy storage device to obtain a fourth judgment result; if the fourth judgment result is yes, the corresponding unit power of each target PCS in the auxiliary energy storage device is decreased; if the fourth judgment result is no, the corresponding unit power of each target PCS in the energy storage device under test is decreased, and then the step of determining whether the absolute value of the current total output power of the energy storage device under test is greater than 0 to obtain the third judgment result is re-executed; if the third judgment result is no, it is determined that the current total output power of the energy storage device under test and the current total output power of the auxiliary energy storage device are both 0, and the process ends.

[0085] In the embodiment of the present invention, the control device is connected to the energy storage device under test and the auxiliary energy storage device respectively. The energy storage device under test and the auxiliary energy storage device both adopt a string-type architecture in which battery clusters are connected to multiple independently controlled PCSs respectively. The AC output terminals of the PCSs in the energy storage device under test and the auxiliary energy storage device are connected in parallel to the same target AC bus of the power grid. When performing a high-power test in the test mode of the energy storage device under test, the auxiliary energy storage device can be used to compensate for the power overflowing the power grid capacity. In addition, for the energy storage device under test and the auxiliary energy storage device of the string-type architecture, the influence of the PCS operating state is considered during the test process, and the joint control of the PCSs in the energy storage device under test and the auxiliary energy storage device is realized. This joint control method can avoid the impact of a single or a small number of PCS failures on the power grid, thereby realizing a high-power test of the energy storage device when the power that the power grid can provide is less than the power required for the test, and at the same time reducing the damage to the power grid caused by a single PCS failure.

[0086] Further optionally, the control device is also connected to a dynamic load energy storage device, and the AC output terminal of the dynamic load energy storage device is connected to the target AC bus of the power grid; the above step S220 includes: based on the first PCS operating status information, the second PCS operating status information and the test mode, controlling each PCS in the energy storage device under test and the auxiliary energy storage device, and the dynamic load energy storage device to charge and discharge through the power grid. The dynamic load energy storage device can provide fault redundancy adjustment for the auxiliary energy storage device, further improving the system stability.

[0087] Optionally, in the process of controlling each PCS in the energy storage device under test and the auxiliary energy storage device, and the dynamic load energy storage device to charge and discharge through the power grid based on the first PCS operating status information, the second PCS operating status information and the test mode, the following formula is satisfied:

[0088]

[0089] Among them, P 1i is the current output power of the i-th PCS in the energy storage device under test, E 1i is the power coefficient corresponding to the operating state of the i-th PCS in the energy storage device under test, n is the number of PCSs in the energy storage device under test, P 2i is the current output power of the i-th PCS in the auxiliary energy storage device, E 2i is the power coefficient corresponding to the operating state of the i-th PCS in the auxiliary energy storage device, m is the number of PCS in the auxiliary energy storage device, the power coefficient corresponding to the PCS in operation in the charging state is -1, the power coefficient corresponding to the PCS in operation in the discharging state is 1, and the power coefficient corresponding to the PCS not in operation is 0, P rated is the total rated power of the energy storage device under test, P limi is the power limit at the grid access interface where the target AC busbar of the grid is located, P load It is used to store dynamic load energy of dynamic load energy storage equipment.

[0090] Optionally, the method further comprises: during the test, detecting the gateway power of the power grid in real time; wherein the gateway power is the output power at the access interface of the power grid, such as Figure 1 The coupled grid-connected point power detected by M; anomaly detection based on the gateway power.

[0091] Specifically, the threshold power can be compared with the preset rated value (ie, the above-mentioned limit power P limi ) are compared. When the gateway power exceeds the rated value, it is determined that an abnormality is detected and the test can be interrupted; when the gateway power does not exceed the rated value, it is determined that no abnormality is detected and the test can continue.

[0092] Furthermore, when an abnormality is detected, an alarm can be issued through a preset alarm method to promptly remind the user of the abnormal situation and handle the abnormal situation in a timely manner. The alarm method can be set according to actual needs and is not limited here, such as using one or more of an audible and visual alarm, SMS reminder, phone reminder, email reminder, etc.

[0093] For ease of understanding, the following will refer to Figure 3 to Figure 4 , the power control process in the two test modes is introduced by way of example.

[0094] Figure 3The power control process of a collaborative control test system in charging mode is shown. Figure 4 The power control process of a collaborative control test system in discharge mode is shown. Figure 3 and Figure 4 The relevant symbols in are introduced:

[0095] E ci is the power coefficient corresponding to the PCS in the i-th charging state; -1: running; 0: shutdown or fault;

[0096] E di is the power coefficient corresponding to the PCS in the i-th discharge state; 1: running; 0: shutdown or fault;

[0097] P ci is the charging power of the i-th PCS;

[0098] P di is the discharge power of the i-th PCS;

[0099] P off is the power of the coupling grid point;

[0100] P limi The limiting power of the coupling grid point, i.e. the maximum threshold power value;

[0101] P load For dynamic load energy storage, charging is a negative power value and discharging is a positive power value;

[0102] △P ci is the charging step increase value of the i-th PCS (i.e. the above-mentioned unit power), a negative power value;

[0103] △P di is the increase in the discharge level of the i-th PCS (i.e., the above-mentioned unit power), a positive power value;

[0104] P rated is the total rated power of the energy storage device under test.

[0105] Taking the case where the number of PCSs in both the energy storage device under test and the auxiliary energy storage device is n, the above-mentioned collaborative control test system should satisfy the following relationship:

[0106]

[0107] In charging mode, the following conditions should be met:

[0108]

[0109] In discharge mode, the following conditions should be met:

[0110]

[0111] like Figure 3 As shown in the figure, the group control process of the charging test is as follows: After the charging test starts, first determine whether the absolute value of the current total output power of the energy storage device under test is less than the total rated power of the energy storage device under test, that is, |∑P ci ×E ci |<P rated ; If yes (i.e. satisfying |∑P ci ×E ci |<P rated ), let P ci =P ci +ΔP ci , P di =P di +ΔP di , and then determine whether the current total output power of the energy storage device under test is greater than the current total output power of the auxiliary energy storage device, that is, |∑P ci ×E ci |>|∑P di ×E di |; If yes (i.e. satisfying |∑P ci ×E ci |>|∑P di ×E di |), let P ci =P ci +0,P di =P di +ΔP di , if not (i.e. does not satisfy |∑P ci ×E ci |>|∑P di ×E di |), let P di =P di +0,P ci =P ci +ΔP ci ; Then re-execute |∑P ci ×E ci |<P rated If no (i.e., it does not satisfy |∑P ci ×E ci |<P rated ), confirm that the energy storage device under test is running at full power, and do not change the output power of each PCS, that is, P di =P di , P ci =P ci .

[0112] At the end of the charging test, it is determined whether the absolute value of the current total output power of the energy storage device under test is greater than 0, that is, |∑P ci ×Eci |>0; if (i.e. satisfying |∑P ci ×E ci |>0), let P ci =P ci -ΔP ci , P di =P di -ΔP di ; Then determine whether the current total output power of the energy storage device under test is less than the current total output power of the auxiliary energy storage device, that is, |∑P ci ×E ci |<|∑P di ×E di |; If yes (i.e. satisfying |∑P ci ×E ci |<|∑P di ×E di |), let P ci =P ci -0,P di =P di -ΔP di ; If not (i.e. does not satisfy |∑P ci ×E ci |<|∑P di ×E di |), let P di =P di -0,P ci =P ci -ΔP ci ; Then re-execute |∑P ci ×E ci |>0 judgment step. If no (i.e., it does not satisfy |∑P ci ×E ci |>0), it is determined that the current total output power of the energy storage device under test and the current total output power of the auxiliary energy storage device are both 0, that is, P di =0,P ci =0, the process ends.

[0113] like Figure 4 As shown in the figure, the group control process of the discharge test is as follows: After the discharge test starts, first determine whether the absolute value of the current total output power of the energy storage device under test is less than the total rated power of the energy storage device under test, that is, |∑P di ×E di |<P rated ; If yes (i.e. satisfying |∑P di ×E di |<P rated ), let P di =P di +ΔP di , P ci =Pci +ΔP ci , and then determine whether the current total output power of the energy storage device under test is greater than the current total output power of the auxiliary energy storage device, that is, |∑P di ×E di |>|∑P ci ×E ci |; If yes (i.e. satisfying |∑P di ×E di |>|∑P ci ×E ci |), let P di =P di +0,P ci =P ci +ΔP ci , if not (i.e. does not satisfy |∑P di ×E di |>|∑P ci ×E ci |), let P ci =P ci +0,P di =P di +ΔP di ; Then re-execute |∑P di ×E di |<P rated If no (i.e., it does not satisfy |∑P di ×E di |<P rated ), confirm that the energy storage device under test is running at full power, and do not change the output power of each PCS, that is, P ci =P ci , P di =P di .

[0114] At the end of the discharge test, determine whether the absolute value of the current total output power of the energy storage device under test is greater than 0, that is, |∑P di ×E di |>0; if (i.e. satisfying |∑P di ×E di |>0), let P di =P di -ΔP di , P ci =P ci -ΔP ci ; Then determine whether the current total output power of the energy storage device under test is less than the current total output power of the auxiliary energy storage device, that is, |∑P di ×E di |<|∑P ci ×E ci |; If yes (i.e. satisfying |∑P di×E di |<|∑P ci ×E ci |), let P di =P di -0,P ci =P ci -ΔP ci ; If not (i.e. does not satisfy |∑P di ×E di |<|∑P ci ×E ci |), let P ci =P ci -0,P di =P di -ΔP di ; Then re-execute |∑P di ×E di |>0 judgment step. If no (i.e., it does not satisfy |∑P di ×E di |>0), it is determined that the current total output power of the energy storage device under test and the current total output power of the auxiliary energy storage device are both 0, that is, P di =0,P ci =0, the process ends.

[0115] The embodiment of the present invention can realize the test of high-power energy storage equipment under the condition of limited power grid power through the coordinated control of three sets of equipment: control equipment, energy storage equipment under test, and auxiliary energy storage equipment. Based on the coordinated control test system, one set of energy storage equipment (i.e., energy storage equipment under test) can be tested at full power, and a test based on 150kW can be realized; at the same time, the damage to the power grid caused by a single PCS failure can be avoided.

[0116] like Figure 5 As shown, a control device 100 provided in an embodiment of the present invention includes: a processor 501, a memory 502 and a bus, the memory 502 stores a computer program that can be run on the processor 501, when the control device 100 is running, the processor 501 and the memory 502 communicate through the bus, and the processor 501 executes the computer program to implement the above-mentioned collaborative control test method applicable to sodium ion energy storage equipment.

[0117] Specifically, the memory 502 and the processor 501 can be general-purpose memories and processors, which are not specifically limited here.

[0118] The embodiment of the present invention also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by the processor, the collaborative control test method applicable to the sodium ion energy storage device in the previous method embodiment is executed. The computer-readable storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a RAM, a magnetic disk or an optical disk, and other media that can store program codes.

[0119] The term "and / or" herein is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the term "at least one" herein represents any combination of at least two of any one or more of a plurality of. For example, including at least one of A, B, and C can represent including any one or more elements selected from the set consisting of A, B, and C.

[0120] In all examples shown and described herein, any specific values ​​should be interpreted as merely exemplary and not as limiting, and thus other examples of the exemplary embodiments may have different values.

[0121] The flow chart and block diagram in the accompanying drawings show the possible architecture, function and operation of the system, method and computer program product according to multiple embodiments of the present invention. In this regard, each box in the flow chart or block diagram can represent a module, a program segment or a part of the code, and a part of the module, program segment or code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flow chart, and the combination of the boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs the specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0122] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A collaborative control test method suitable for sodium ion energy storage equipment, characterized in that: Applied to a control device, the control device is connected to a tested energy storage device and an auxiliary energy storage device respectively, the tested energy storage device and the auxiliary energy storage device both adopt a string-type architecture in which battery clusters are connected to a plurality of independently controlled energy storage converters PCS respectively, and the AC output terminals of the tested energy storage device and each of the PCSs in the auxiliary energy storage device are connected in parallel to the same target AC bus of the power grid; the method comprises: In response to a test start instruction, obtaining a test mode of the energy storage device under test; wherein the test mode includes a charging mode or a discharging mode; During the test, the first PCS operating status information corresponding to the energy storage device under test and the second PCS operating status information corresponding to the auxiliary energy storage device are obtained in real time, and based on the first PCS operating status information, the second PCS operating status information and the test mode, each PCS in the energy storage device under test and the auxiliary energy storage device is controlled to charge and discharge through the power grid; wherein the charging and discharging state of the energy storage device under test is opposite to the charging and discharging state of the auxiliary energy storage device, and the auxiliary energy storage device is used to charge and discharge through the power grid to compensate for the output power of the power grid.

2. The method according to claim 1, characterized in that The controlling each PCS in the energy storage device under test and the auxiliary energy storage device to charge and discharge through the power grid based on the first PCS operation status information, the second PCS operation status information and the test mode includes: Based on the first PCS operation state information, the current output power of each of the PCSs in the energy storage device under test and the test mode, calculate and obtain the current total output power of the energy storage device under test; Determine whether the absolute value of the current total output power of the energy storage device under test is less than the total rated power of the energy storage device under test, and obtain a first determination result; If the first judgment result is yes, based on the second PCS operation status information, the current output power of each of the PCSs in the auxiliary energy storage device and the test mode, calculate the current total output power of the auxiliary energy storage device; Based on the current total output power of the energy storage device under test and the current total output power of the auxiliary energy storage device, dynamically increasing the output power of each target PCS in the energy storage device under test and the auxiliary energy storage device; wherein the target PCS is a running PCS; Re-execute the step of determining whether the absolute value of the current total output power of the energy storage device under test is less than the total rated power of the energy storage device under test to obtain a first determination result until the energy storage device under test runs at full power; Among them, when the test mode is the charging mode, the energy storage device under test is charged through the power grid, the current total output power of the energy storage device under test is a negative value, the auxiliary energy storage device is discharged through the power grid, and the current total output power of the auxiliary energy storage device is a positive value; when the test mode is the discharging mode, the energy storage device under test is discharged through the power grid, the current total output power of the energy storage device under test is a positive value, the auxiliary energy storage device is charged through the power grid, and the current total output power of the auxiliary energy storage device is a negative value.

3. The method according to claim 2, characterized in that The calculating the current total output power of the energy storage device under test based on the first PCS operation status information, the current output power of each of the PCSs in the energy storage device under test, and the test mode includes: The current total output power P1 of the energy storage device under test is calculated by the following formula: Among them, P 1i is the current output power of the i-th PCS in the energy storage device under test, E 1i is the power coefficient corresponding to the operating state of the i-th PCS in the energy storage device under test, n is the number of PCSs in the energy storage device under test, the power coefficient corresponding to the PCS running in the charging state is -1, the power coefficient corresponding to the PCS running in the discharging state is 1, and the power coefficient corresponding to the PCS not running is 0.

4. The method according to claim 2, characterized in that: The dynamically increasing the output power of each target PCS in the energy storage device under test and the auxiliary energy storage device based on the current total output power of the energy storage device under test and the current total output power of the auxiliary energy storage device includes: Increasing the corresponding unit power of each target PCS in the energy storage device under test and the auxiliary energy storage device, and updating the current total output power of the energy storage device under test and the current total output power of the auxiliary energy storage device; Determine whether the absolute value of the current total output power of the energy storage device under test is greater than the absolute value of the current total output power of the auxiliary energy storage device, and obtain a second determination result; Based on the second judgment result, the corresponding unit power of each target PCS in the energy storage device under test or the auxiliary energy storage device is increased incrementally.

5. The method according to claim 2, characterized in that: Each of the PCSs in the energy storage device under test and the auxiliary energy storage device is configured with redundant power, and the method further includes: If the first judgment result is no, determining that the energy storage device under test is operating at full power; During the full-power operation of the energy storage device under test, the output power of each target PCS in the energy storage device under test is dynamically allocated based on the first PCS operating status information, and the output power of each target PCS in the auxiliary energy storage device is dynamically allocated based on the second PCS operating status information.

6. The method according to claim 2, characterized in that After the energy storage device under test is running at full power, the method further includes: In response to the test end event, the output power of each target PCS in the energy storage device under test and the auxiliary energy storage device is dynamically reduced until the current total output power of the energy storage device under test and the current total output power of the auxiliary energy storage device are both 0; wherein the test end event includes a first event corresponding to a test end instruction input by the user, or a second event corresponding to a full-power operation time reaching a preset time.

7. The method according to any one of claims 1 to 6, characterized in that The control device is also connected to a dynamic load energy storage device, and the AC output end of the dynamic load energy storage device is connected to the target AC bus of the power grid; based on the first PCS operating status information, the second PCS operating status information and the test mode, controlling each PCS in the energy storage device under test and the auxiliary energy storage device to charge and discharge through the power grid, including: Based on the first PCS operating status information, the second PCS operating status information and the test mode, the PCSs in the energy storage device under test and the auxiliary energy storage device, and the dynamic load energy storage device are controlled to charge and discharge through the power grid.

8. The method according to claim 7, characterized in that In the process of controlling the tested energy storage device and each PCS in the auxiliary energy storage device, and the dynamic load energy storage device to charge and discharge through the power grid based on the first PCS operating status information, the second PCS operating status information and the test mode, the following formula is satisfied: Among them, P 1i is the current output power of the i-th PCS in the energy storage device under test, E 1i is the power coefficient corresponding to the operating state of the i-th PCS in the energy storage device under test, n is the number of PCSs in the energy storage device under test, P 2i is the current output power of the i-th PCS in the auxiliary energy storage device, E 2i is the power coefficient corresponding to the operating state of the i-th PCS in the auxiliary energy storage device, m is the number of PCSs in the auxiliary energy storage device, the power coefficient corresponding to the PCS in operation in the charging state is -1, the power coefficient corresponding to the PCS in operation in the discharging state is 1, and the power coefficient corresponding to the PCS not in operation is 0, P rated is the total rated power of the energy storage device under test, P limi is the power limit at the grid access interface where the target AC bus of the grid is located, P load The dynamic load energy storage device stores dynamic load energy.

9. A control device, comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, characterized in that: When the processor executes the computer program, the collaborative control test method applicable to sodium ion energy storage equipment described in any one of claims 1-8 is implemented.

10. A collaborative control test system suitable for sodium ion energy storage equipment, characterized in that: The invention comprises the control device as claimed in claim 9, and further comprises a tested energy storage device and an auxiliary energy storage device respectively connected to the control device.

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