Control method of combined power supply system of generator set and energy storage system and combined power supply system

Abstract

The invention relates to the technical field of combined power supply, in particular to a control method of a combined power supply system of a generator set and an energy storage system and the combined power supply system. The method comprises the following steps: when the current required power of a load is smaller than a power required threshold value, controlling an energy storage system to supply power to the load; in the power supply process, when it is monitored that the energy storage system cannot meet the power supply requirement of the load, if it is determined that the generator set is put into use for power supply, the output power of the generator set is determined according to the current required power of the load and the output power of the energy storage system when the current required power of the load is smaller than a power required threshold value; determining the target state of the energy storage system and the power in the target state according to the current required power of the load and the output power of the generator set; and controlling the generator set to supply power to the load according to the corresponding output power, and controlling the energy storage system to work in the target state and the corresponding power. The method can reduce the influence of the abrupt change load on the generator set and keep the power supply stable.

Description

Technical Field

[0001] The present application relates to the technical field of combined power supply, and in particular to a control method for a combined power supply system of a generator set and an energy storage system, and a combined power supply system of a generator set and an energy storage system. Background Art

[0002] In the context of energy conservation and emission reduction, the energy structure is shifting from traditional high-carbon emission energy structures to low-carbon emission clean energy structures. In the oil and gas field sector, there is a green development goal of replacing oil with electricity, thereby replacing diesel with electric drive.

[0003] However, most oil and gas field wellsites are located in remote locations with inadequate power grid infrastructure, making it difficult to meet high-power capacity requirements. Traditionally, portable generator sets have been used to replace the grid. However, in practice, these generator sets are susceptible to sudden load fluctuations during power generation, resulting in power supply fluctuations and failing to meet the stable power output requirements of oil and gas field wellsites during oilfield production. Summary of the Invention

[0004] Based on this, it is necessary to provide a control method for a combined power supply system of a generator set and an energy storage system, as well as a combined power supply system of a generator set and an energy storage system, which can reduce the impact of sudden load on the generator set and maintain stable power supply to address the above technical problems.

[0005] In a first aspect, the present application provides a method for controlling a power supply system in which a generator set and an energy storage system are combined. The method is performed by a controller and includes:

[0006] When the current power demand of the load is less than the power demand threshold, controlling the energy storage system to supply power to the load;

[0007] During the power supply process, if it is detected that the energy storage system fails to meet the power supply demand of the load, if it is determined that the generator set will be put into power supply, the output power of the generator set will be determined based on the current power demand of the load and the output power of the energy storage system when the current power demand of the load is less than the power demand threshold;

[0008] Determine the target state of the energy storage system and the power at the target state based on the current power demand of the load and the output power of the generator set; the target state is either a charging state or a discharging state;

[0009] Control the generator set to supply power to the load according to the corresponding output power, and control the energy storage system to operate at the target state and corresponding power.

[0010] In one embodiment, when there are at least two energy storage systems, the step of determining the power of the energy storage system at the target state based on the current power demand of the load and the output power of the generator set further includes:

[0011] Determine the number of controllable energy storage systems; a controllable energy storage system is an energy storage system that can be controlled by a controller;

[0012] The difference between the current power demand of the load and the output power of the generator set is used to obtain the differential power;

[0013] According to the difference power and quantity, the power of each controllable energy storage system at the target state is obtained.

[0014] In one embodiment, after controlling the generator set to supply power to the load according to the corresponding output power, the method further includes:

[0015] When the generator set is in an emergency state, determining the preset power for the uncontrollable energy storage system; the uncontrollable energy storage system is an energy storage system that is not controllable by the controller;

[0016] The maximum value between the preset power and the power in the target state is determined as the emergency discharge power of the uncontrollable energy storage system;

[0017] Control the uncontrollable energy storage system to operate according to the emergency discharge power.

[0018] In one embodiment, the target state is a discharge state, and the method further includes:

[0019] When the generator set is supplying power to the load and the energy storage system is operating in a discharging state and at a corresponding power level, if it is detected that the fluctuation range of the current power demand of the load is greater than or equal to a preset fluctuation range, and the output power of the generator set is higher than the upper limit of the output power, the discharge power of the energy storage system is increased until the maximum discharge power of the energy storage system is reached.

[0020] When the fluctuation amplitude of the current power demand of the load is greater than or equal to the preset fluctuation amplitude and the output power of the generator set is lower than the output power lower limit, the discharge power of the energy storage system is reduced until the minimum discharge power of the energy storage system is reached.

[0021] In one embodiment, the method further comprises:

[0022] During the discharging process of the energy storage system, when the remaining power of the energy storage system is lower than the lower power limit and the energy storage system is in the discharging state, a stop discharging instruction is sent to the energy storage system;

[0023] During the charging process of the energy storage system, when the remaining power of the energy storage system is higher than the upper limit of power and the energy storage system is in a charging state, a stop charging instruction is sent to the energy storage system.

[0024] In one embodiment, the method further comprises:

[0025] The active power of the converter is determined based on the power of the energy storage system in the target state and the maximum chargeable and dischargeable power value of the converter in the energy storage system.

[0026] In one embodiment, when the energy storage system includes at least two converters, the method further includes:

[0027] The active power of the target converter is determined according to the maximum chargeable and dischargeable power distribution ratio of the target converter and the power of the energy storage system in the target state; wherein the target converter is any converter in the energy storage system.

[0028] In one embodiment, when the energy storage system includes at least two converters and at least two battery stacks, the method further includes:

[0029] The active power of the target converter is determined based on the weight ratio of the target converter, the weight ratio of the target battery stack, the sum of the weight ratios of each converter, and the power of the energy storage system in the target state; wherein the target converter is any converter in the energy storage system; the converter and the battery stack have a one-to-one correspondence; wherein the weight ratio of the target converter is determined based on the maximum chargeable and dischargeable power value.

[0030] In one embodiment, the method further comprises:

[0031] During the power supply process, if it is monitored that the energy storage system fails to meet the power supply demand of the load, if it is determined to increase the number of energy storage systems, the output power of each energy storage system will be re-determined based on the current power demand of the load and the number of energy storage systems.

[0032] In a second aspect, the present application further provides a combined power supply system of a generator set and an energy storage system, comprising:

[0033] Generator sets;

[0034] Energy storage systems;

[0035] A controller is connected to the generator set, the energy storage system and the load respectively; the controller is used to execute the steps of any one of the above-mentioned methods for controlling a combined power supply system of a generator set and an energy storage system.

[0036] In the control method for the combined power supply system of a generator set and an energy storage system, and the combined power supply system of a generator set and an energy storage system, the controller first controls the energy storage system to supply power to the load. During the power supply process, as the power supply demand of the load increases until it reaches a point where the energy storage system cannot meet it, if it is determined that the generator set is put into power supply, the generator set is controlled to start, so that the generator set can supply power to the load. Such a power supply design greatly reduces the impact of sudden load changes on the generator set, allowing the generator set to be in a stable working state. When it is determined that the generator set is put into power supply, the output power of the generator set is determined based on the current power demand of the load and the output power of the energy storage system when the current power demand of the load is less than the power demand threshold; then, based on the current power demand of the load and the output power of the generator set, the target state of the energy storage system and the power at the target state are determined, and the generator set is controlled to supply power to the load according to the corresponding output power, and the energy storage system is controlled to operate at the target state and corresponding power, so that the output power of the generator set and the corresponding power of the energy storage system can meet the power supply demand of the load and maintain stable power supply to the load. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following briefly introduces the drawings required for use in the embodiments of the present application or related technical descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying any creative work.

[0038] Figure 1 This is a diagram of an application environment of a control method for a combined power supply system of a generator set and an energy storage system in one embodiment;

[0039] Figure 2 1 is a flow chart of a method for controlling a power supply system in which a generator set and an energy storage system are combined;

[0040] Figure 3 1 is a flow chart illustrating steps for determining the power of an energy storage system at a target state based on the current power demand of a load and the output power of a generator set in one embodiment;

[0041] Figure 4 A schematic diagram of a control strategy of a method for controlling a power supply system jointly powered by a generator set and an energy storage system in a low-power demand power supply mode according to an embodiment;

[0042] Figure 5 A schematic diagram of a control strategy of a method for controlling a power supply system jointly powered by a generator set and an energy storage system in a high-power demand power supply mode according to an embodiment;

[0043] Figure 6Schematic diagram of the control strategy of a single-control switch in a closed state and an open state in one embodiment;

[0044] Figure 7 A structural block diagram of a control device for a combined power supply system of a generator set and an energy storage system in one embodiment;

[0045] Figure 8 FIG. 1 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0047] The control method of the generator set and energy storage system combined power supply system provided in the embodiment of the present application can be applied to Figure 1 In the application environment shown. The controller 102 obtains the current power demand of the load 200. When the current power demand of the load 200 is less than a preset power demand threshold, the controller 102 controls the energy storage system 104 to supply power to the load 200 alone. During the power supply process, the controller 102 monitors the power supply status of the energy storage system in real time. When the controller 102 detects that the energy storage system fails to meet the power demand of the load 200 and determines that the generator set 106 is to be used for joint power supply, the controller 102 determines the output power of the generator set 106 based on the current power demand of the load 200 and the output power of the energy storage system when the current power demand of the load 200 is less than the power demand threshold. The controller 102 then determines the target state of the energy storage system and the power corresponding to the target state based on the current power demand of the load 200 and the determined output power of the generator set 106. The controller 102 controls the generator set 106 to operate according to the output power determined above to supply power to the load 200, while controlling the energy storage system 104 to operate at the target state and corresponding power. The target state includes a charging state and a discharging state.

[0048] In an exemplary embodiment, Figure 2 As shown, a control method for a power supply system jointly powered by a generator set and an energy storage system is provided. Figure 1 The controller in the example is used to illustrate the following:

[0049] S202 : When the current power demand of the load is less than the power demand threshold, control the energy storage system to supply power to the load.

[0050] When the load's current power demand is less than the power demand threshold, the load is powered solely by the energy storage system. In this case, the energy storage system can be set to off-grid mode, allowing it to self-start and establish a voltage independently of an external voltage. Exemplarily, this voltage can be anywhere in the range of 10.3kV to 10.8kV. Preferably, this voltage is 10.5kV.

[0051] The source of the electric energy stored in the energy storage system in off-grid mode can be the electric energy generated by renewable energy equipment, such as photovoltaic power generation equipment and wind power generation equipment.

[0052] S204: During the power supply process, if it is detected that the energy storage system fails to meet the power supply demand of the load, if it is determined that the generator set is to be put into use for power supply, the output power of the generator set is determined based on the current power demand of the load and the output power of the energy storage system when the current power demand of the load is less than the power demand threshold.

[0053] While the energy storage system is supplying power to the load, the controller can monitor the system's power supply in real time. If it detects that the energy storage system is failing to meet the load's power needs, it can determine and supply power to the load based on a new power supply strategy, which may include switching on a generator set.

[0054] S206 , determining a target state of the energy storage system and the power at the target state based on the current power demand of the load and the output power of the generator set; the target state is a charging state or a discharging state.

[0055] S208, controlling the generator set to supply power to the load according to the corresponding output power, and controlling the energy storage system to operate at the target state and corresponding power.

[0056] The output power of a generator set at a constant temperature is essentially constant, but the current power demand of the load may change in real time. Therefore, when the output power of the generator set is greater than the current power demand of the load, the target state of the energy storage system is determined to be the charging state. The power of the energy storage system in this charging state is the difference between the output power of the generator set and the current power demand of the load, thereby preventing excessive output power from burning the load and ensuring safe operation of the load.

[0057] Correspondingly, when the output power of the generator set is less than the current power demand of the load, the target state of the energy storage system is determined to be the discharge state. The power of the energy storage system in this discharge state is the difference between the current power demand of the load and the output power of the generator set, so that the generator set and the energy storage system can jointly supply power to the load and meet the power supply demand of the load.

[0058] With the generators in operation, the energy storage system can be set to grid-connected mode. This connection is only possible when the voltage of the external grid is within a preset voltage range. This allows the system to interact with the external grid in real time, optimizing energy distribution.

[0059] In the control method for the combined power supply system of the generator set and the energy storage system, the controller first controls the energy storage system to supply power to the load. During the power supply process, as the power supply demand of the load increases, until it reaches a point where the energy storage system cannot meet it, if it is determined that the generator set is put into power supply, the controller controls the generator set to start, so that the generator set can supply power to the load. Such a power supply design greatly reduces the impact of sudden load on the generator set, so that the generator set can be in a stable working state. When it is determined that the generator set is put into power supply, the output power of the generator set is determined based on the current power demand of the load and the output power of the energy storage system when the current power demand of the load is less than the power demand threshold; then, based on the current power demand of the load and the output power of the generator set, the target state of the energy storage system and the power at the target state are determined, and the generator set is controlled to supply power to the load according to the corresponding output power. The energy storage system is controlled to operate at the target state and the corresponding power, so that the output power of the generator set and the corresponding power of the energy storage system can meet the power supply demand of the load and maintain the stability of the power supply to the load.

[0060] In one embodiment, the output power of the generator set may also be determined according to the fuel consumption and the amount of fuel consumed per unit power generation.

[0061] Specifically, when the generator set consumes natural gas, the natural gas consumption and the gas-to-electricity ratio are determined, and the output power of the generator set consuming natural gas can be determined based on the natural gas consumption and the gas-to-electricity ratio.

[0062] Correspondingly, when the generator set is a generator set that consumes fuel, the fuel consumption and the fuel-to-electricity ratio are determined, and the output power of the generator set that consumes fuel can be determined based on the fuel consumption and the fuel-to-electricity ratio.

[0063] The operating efficiency and economic benefits of the generator set can be evaluated based on the gas-to-electricity ratio or the oil-to-electricity ratio, so that the staff can adjust the generator set based on the gas-to-electricity ratio or the oil-to-electricity ratio to make the generator set operate at the best efficiency.

[0064] In an exemplary embodiment, Figure 3 As shown, when there are at least two energy storage systems, the step of determining the power of the energy storage system at the target state according to the current required power of the load and the output power of the generator set includes:

[0065] S302, determining the number of controllable energy storage systems; a controllable energy storage system is an energy storage system that is controllable by a controller.

[0066] S304: Obtain the power difference according to the difference between the current power demand of the load and the output power of the generator set.

[0067] S306 , obtaining the power of each controllable energy storage system in the target state according to the difference power and quantity.

[0068] It should be noted that multiple energy storage systems can be set up in the power supply system of the combined generator set and energy storage system. These energy storage systems include controller-controllable energy storage systems and controller-uncontrollable energy storage systems. Among them, the controller-controllable energy storage system can be understood as an energy storage system that can be controlled by the controller for power distribution, which can be simply referred to as a controllable energy storage system; the controller's control of the controllable energy storage system includes: determining the power allocated to each controllable energy storage system based on the differential power, and controlling each controllable energy storage system to operate at the allocated power; the controller-uncontrollable energy storage system can be understood as an energy storage system whose power distribution is not controlled by the controller, which can be simply referred to as an uncontrollable energy storage system; the uncontrollable energy storage system operates according to instructions issued by the staff that carry the corresponding target state and power.

[0069] In one embodiment, the power of each energy storage system in the target state can be an averaged power calculated based on the differential power and the number of controllable energy storage systems. For example, if there are three controllable energy storage systems and the differential power is 3000W, the power allocated to each controllable energy storage system is 1000W.

[0070] In one embodiment, the power of each energy storage system in the target state may also be proportional power obtained by performing proportional distribution calculation based on a preset distribution ratio, differential power, and quantity of each energy storage system.

[0071] In one embodiment, single-control switches may be provided to be connected to corresponding energy storage systems, wherein the number of single-control switches is less than or equal to the number of energy storage systems. When a single-control switch is closed, the energy storage system connected to the closed single-control switch is an uncontrollable energy storage system; when the single-control switch is open, the energy storage system connected to the open single-control switch is a controllable energy storage system.

[0072] In one embodiment, when any single-control switch is opened or closed, the corresponding power of the energy storage system corresponding to the single-control switch is immediately restored to zero. It should be noted that when any single-control switch is opened and closed, the number of controllable energy storage systems will change. In this case, the power of each controllable energy storage system in the target state will be based on the current power demand of the load and the output power of the generator set. For example, when the number of controllable energy storage systems is 3 and the power allocated to each controllable energy storage system is 1000W, if the single-control switch corresponding to any controllable energy storage system is closed, the number of controllable energy storage systems changes to 2, and the power allocated to each controllable energy storage system changes to 1500W. The power allocated to the uncontrollable energy storage system is the default value, which can be 0. The staff can adjust the power of the uncontrollable energy storage system so that the power of the uncontrollable energy storage system is the power adjusted by the staff.

[0073] In one embodiment, a human-computer interaction module connected to the uncontrollable energy storage system can be set up so that the staff can input the corresponding target state and power based on the human-computer interaction module, so that the uncontrollable energy storage system can operate at the input target state and power to achieve the purpose of independent control.

[0074] For example, when the remaining power of at least one energy storage system is inconsistent with the remaining power of other energy storage systems, the single-control switch corresponding to the energy storage system can be closed to switch the energy storage system from a controller-controllable state to a controller-uncontrollable state, so as to adjust the remaining power of the uncontrollable energy storage system by entering the corresponding target state and power, thereby ensuring the consistency of the remaining power of all energy storage systems.

[0075] In an exemplary embodiment, after controlling the generator set to supply power to the load according to the corresponding output power, the control method of the generator set and energy storage system combined power supply system further includes:

[0076] When the generator set is in an emergency state, a preset power for the uncontrollable energy storage system is determined; the uncontrollable energy storage system is an energy storage system that is not controllable by the controller.

[0077] The maximum value between the preset power and the power in the target state is determined as the emergency discharge power of the uncontrollable energy storage system.

[0078] Control the uncontrollable energy storage system to operate according to the emergency discharge power.

[0079] If the actual temperature of a generator set exceeds the safety temperature threshold, the generator set is considered to be in an emergency state. For example, if the optimal operating temperature of the generator set is 800 degrees Celsius, the safety temperature threshold of the generator set can be set to 900 degrees Celsius. When the actual temperature of the generator set rises to 900 degrees Celsius, the generator set is considered to be in an emergency state.

[0080] When the generator set is in an emergency state, controlling the uncontrollable energy storage system to operate at emergency discharge power can fill the power gap caused by the surge in load power demand, so as to quickly restore the balance of the power grid and reduce the risk of power outages.

[0081] In an exemplary embodiment, the target state is a discharging state, and the control method of the combined power supply system of the generator set and the energy storage system further includes:

[0082] In the process of supplying power to the load through the generator set and the energy storage system operating in a discharge state and at the corresponding power, when it is monitored that the fluctuation amplitude of the current power demand of the load is greater than or equal to the preset fluctuation amplitude, and the output power of the generator set is higher than the output power upper limit, the discharge power of the energy storage system is increased until the maximum discharge power of the energy storage system is reached.

[0083] When the output power of the generator set is higher than the output power upper limit, if the fluctuation amplitude of the current demand power of the load is monitored to be greater than or equal to the preset fluctuation amplitude, it means that the power supply demand of the load exceeds the upper limit of the output power of the generator set. At this time, the discharge power of the energy storage system can be increased to prevent the generator set from being overloaded, while also meeting the power supply demand of the load and maintaining stable power supply.

[0084] When the fluctuation amplitude of the current power demand of the load is greater than or equal to the preset fluctuation amplitude and the output power of the generator set is lower than the output power lower limit, the discharge power of the energy storage system is reduced until the minimum discharge power of the energy storage system is reached.

[0085] Correspondingly, when the output power of the generator set is lower than the lower limit of the output power, if the fluctuation amplitude of the current demand power of the load is monitored to be greater than or equal to the preset fluctuation amplitude, it means that the power supply demand of the load is lower than the lower limit of the output power of the generator set. At this time, the anti-reverse power protection of the generator set can be performed by reducing the discharge power of the energy storage system, while also meeting the power supply demand of the load and maintaining stable power supply.

[0086] In one embodiment, multiple output power thresholds of different levels can be set. When the fluctuation amplitude of the current power demand of the load is greater than or equal to the preset fluctuation amplitude, and the output power of the generator set is higher than the current output power threshold, the output power threshold is increased by one level in the direction of increasing the output power threshold level until the maximum output power threshold is reached. Correspondingly, when the fluctuation amplitude of the current power demand of the load is greater than or equal to the preset fluctuation amplitude, and the output power of the generator set is lower than the current output power threshold, the output power threshold is increased by one level in the direction of decreasing the output power threshold level until the minimum output power threshold is reached. The higher the level of the output power threshold, the larger the value.

[0087] In an exemplary embodiment, the control method of the combined power supply system of the generator set and the energy storage system further includes:

[0088] During the discharging process of the energy storage system, when the remaining power of the energy storage system is lower than the lower power limit and the energy storage system is in a discharging state, a stop discharging instruction is sent to the energy storage system.

[0089] When receiving a stop-discharge instruction, the energy storage system stops discharging, thereby avoiding over-discharge of the energy storage system, maintaining the capacity of the energy storage system, and extending the cycle life. At the same time, it can also avoid sudden power outages in the energy storage system and ensure the stability of power supply.

[0090] During the charging process of the energy storage system, when the remaining power of the energy storage system is higher than the upper power limit and the energy storage system is in a charging state, a stop charging instruction is sent to the energy storage system. The stop charging instruction can be a 0 power instruction.

[0091] Correspondingly, when a stop charging instruction is received, the energy storage system stops charging, thereby avoiding overcharging of the energy storage system, and preventing decomposition of internal materials of the energy storage system causing expansion or even explosion, thereby extending battery life and reducing replacement costs.

[0092] In an exemplary embodiment, the control method of the combined power supply system of the generator set and the energy storage system further includes:

[0093] The active power of the converter is determined based on the power of the energy storage system in the target state and the maximum chargeable and dischargeable power value of the converter in the energy storage system.

[0094] When converting electrical energy, converters incur energy losses, typically expressed as an efficiency percentage. The converter's active power affects its performance and, consequently, the energy storage system's charge and discharge efficiency. Therefore, determining the converter's active power can determine the energy storage system's charge and discharge efficiency, helping personnel determine adjustments to maintain a stable power supply.

[0095] In an exemplary embodiment, when the energy storage system includes at least two converters, the control method of the combined power supply system of the generator set and the energy storage system further includes:

[0096] The active power of the target converter is determined according to the maximum chargeable and dischargeable power distribution ratio of the target converter and the power of the energy storage system in the target state; wherein the target converter is any converter in the energy storage system.

[0097] The active power of the converter can be determined based on the following formula:

[0098]

[0099] in, is the active power of the i-th converter; is the maximum charge and discharge power value of the i-th converter; L is the number of converters; is the power of the energy storage system at the target state.

[0100] Optionally, the minimum value between the charge and discharge power limit corresponding to the converter and the charge and discharge power limit of the battery management system in the energy storage system can be taken as the calculated maximum charge and discharge power value of the corresponding converter, so that when the charge and discharge power limits provided by each converter manufacturer and the charge and discharge power limits obtained by the converter from the battery compartment of the energy storage system and determined by the battery management system are different, a reliable maximum charge and discharge power value can still be determined.

[0101] In an exemplary embodiment, when the energy storage system includes at least two converters and at least two battery stacks, the control method of the combined power supply system of the generator set and the energy storage system further includes:

[0102] The active power of the target converter is determined based on the weight ratio of the target converter, the weight ratio of the target battery stack, the sum of the weight ratios of each converter, and the power of the energy storage system in the target state; wherein the target converter is any converter in the energy storage system; the converter and the battery stack have a one-to-one correspondence; wherein the weight ratio of the target converter is determined based on the maximum chargeable and dischargeable power value.

[0103] The active power of the converter can be determined based on the following formula:

[0104]

[0105] in, is the weight of the maximum charge and discharge power value of the converter, is the weight of the remaining power of the energy storage system battery stack, is the ratio of the maximum chargeable and dischargeable power value of the i-th converter to the maximum chargeable and dischargeable power value of all converters; when calculating the charging power target value, The difference between the remaining power of the ith battery stack and 100% is 100%. When calculating the discharge power target value, The remaining power of the i-th battery stack is 100%, that is, is the weight ratio of the target converter, is the weight ratio of the target battery stack.

[0106] The mode of optimizing control based on the remaining power of the battery stack comprehensively considers the maximum charge and discharge power value and the remaining power of the battery stack to distribute the power weight of the energy storage system in the target state, and can obtain reliable active power of the converter.

[0107] In one embodiment, the maximum charge and discharge power value of the converter and the remaining power of the battery stack can be processed and then substituted into the above formula. The data processing includes normalization.

[0108] In an exemplary embodiment, the control method of the combined power supply system of the generator set and the energy storage system further includes:

[0109] During the power supply process, if it is monitored that the energy storage system fails to meet the power supply demand of the load, if it is determined to increase the number of energy storage systems, the output power of each energy storage system will be re-determined based on the current power demand of the load and the number of energy storage systems.

[0110] After adding more energy storage systems, the output power of each energy storage system is redistributed based on the current power demand of the load and the number of energy storage systems, ensuring the consistency of the remaining power of the energy storage systems in use. The added energy storage systems can be set to off-grid mode.

[0111] In one embodiment, when communication between a generator set or an energy storage system is interrupted, the output power of the generator set is controlled to zero, and the energy storage system is controlled to stop working, thereby avoiding the problem of uncontrolled power supply of the combined power supply system of the generator set and the energy storage system and improving the stability of the combined power supply system of the generator set and the energy storage system.

[0112] In one embodiment, when the current power demand of the load is greater than the alarm threshold, an alarm signal is generated and output, so that when the staff receives the alarm signal, they can determine whether to put the generator set into power supply or increase the power supply of the energy storage system based on the current power demand of the load.

[0113] In one embodiment, the controller may be a PLC (Programmable Logic Controller).

[0114] In an exemplary embodiment, a combined power supply system of a generator set and an energy storage system is provided, comprising: a generator set, an energy storage system, and a controller, wherein the controller is respectively connected to the generator set, the energy storage system, and the load; and the controller is used to execute the steps of any one of the above-mentioned control methods for the combined power supply system of the generator set and the energy storage system.

[0115] The combined power supply system of a generator set and an energy storage system equipped with the above-mentioned control method for the combined power supply system of a generator set and an energy storage system can reduce the impact load on the generator set, and can also maintain the stability of the power supply through the separate power supply of the energy storage system or the combined power supply of the energy storage system and the generator set.

[0116] The present application also provides an embodiment, in which a generator set and energy storage system combined power supply system includes: a generator set, a parallel cabinet, an energy storage system and a load (also referred to as an electrical load).

[0117] Leveraging the fast response speed and strong ramping capability of the power electronics modules in the combined generator set and energy storage system, the energy storage system can quickly capture frequency drops and adjust the system's output power before the generator set responds to impact loads, discharging power to maintain a stable power supply. When the generator set overshoots, the energy storage system quickly absorbs energy, suppresses frequency fluctuations, increases damping, and maintains a stable power supply. Furthermore, when the power required by the load is low, the energy storage system absorbs excess power generated by the generator set, allowing the gas-fired generator to operate within its optimal efficiency range, improving the gas-to-electricity ratio and reducing costs while still meeting the load's power supply needs.

[0118] The generator set includes a human-machine interface module (touch screen or industrial computer), a switch, a lower-level PLC system, a parallel controller, an excitation controller, a generator switchgear, integrated protection devices, a busbar PT (potential transformer) cabinet, and a transformer cabinet. The energy storage system includes an energy management system, a converter, a battery management system, a busbar cabinet, batteries (battery stacks), a fire protection system, a temperature control system, a transformer, an isolation switchgear, and a microcomputer protection device.

[0119] The generator set and energy storage system output a 10.5kV voltage to supply power to the load through the parallel cabinet. The lower-level PLC system of the generator set is the master control system, which can issue charging and discharging power instructions to the energy storage system. It is connected to the energy storage system via Ethernet communication. The human-computer interaction module can display various parameters involved in the joint power supply system of the generator set and energy storage system.

[0120] This embodiment includes a low-power demand power supply mode and a high-power demand power supply mode.

[0121] like Figure 4 As shown, in the low-power demand power supply mode, the PLC obtains the current power demand of the load. When the current power demand of the load is less than the power demand threshold, the number of energy storage systems that have been put into use and are in off-grid mode is determined, and the output power of each energy storage system is determined based on the current power demand of the load and the number of energy storage systems that have been put into use, so as to control each energy storage system to supply power to the load. During the power supply process, the power supply status of the energy storage system is continuously monitored. When it is detected that the energy storage system fails to meet the power supply demand of the load, the PLC can generate and output an alarm signal, so that the staff can judge whether to put the generator set into power supply or increase the number of energy storage systems based on the current power demand of the load.

[0122] If the PLC determines that the number of energy storage systems to be supplied should be increased, it will then add more energy storage systems and then re-determine the output power of each energy storage system based on the current power demand of the load and the number of energy storage systems added. If there are multiple energy storage systems, and some have non-zero remaining power and are not in use, the decision to increase the number of energy storage systems to be supplied can be made.

[0123] like Figure 5 As shown, if it is determined that the generator set is put into use for power supply, the high-power demand power supply mode is entered. In the high-power demand power supply mode, the output power of the generator set is determined based on the current power demand of the load and the output power of the energy storage system when the current power demand of the load is less than the power demand threshold; the target state of the energy storage system and the power at the target state are determined based on the current power demand of the load and the output power of the generator set; the generator set is controlled to supply power to the load based on the determined output power of the generator set, the energy storage system is controlled to operate based on the determined target state and corresponding power, and the energy storage system is connected to the grid so that the energy storage system operates in the grid-connected mode; wherein, as Figure 6 As shown, in the case of multiple energy storage systems, the single-control switch corresponding to any energy storage system can be closed so that the staff can independently control the working status of the energy storage system, while the energy storage systems corresponding to other single-control switches in the disconnected state jointly bear the difference power determined by the current demand power of the load and the output power of the generator set; the single-control switch can be in the closed state by default.

[0124] When any single-control switch is opened or closed, the corresponding power of the energy storage system corresponding to the single-control switch is immediately restored to zero. It should be noted that when any single-control switch is opened and closed, the number of controllable energy storage systems will change. In this case, the power of each controllable energy storage system at the target state will be based on the current power demand of the load and the output power of the generator set. For example, when the number of controllable energy storage systems is 3 and the power allocated to each controllable energy storage system is 1000W, if the single-control switch corresponding to any controllable energy storage system is closed, the number of controllable energy storage systems changes to 2, and the power allocated to each controllable energy storage system changes to 1500W. The power allocated to the uncontrollable energy storage system is the default value, which can be 0. The staff can adjust the power of the uncontrollable energy storage system so that the power of the uncontrollable energy storage system is the power adjusted by the staff.

[0125] To avoid conflicts between automatic program instructions and manual instructions in emergency situations, the principle of maximizing the discharge power of the energy storage system can be followed:

[0126] When the energy storage system is in the discharging state, it can be discharged according to the discharge power given by the PLC (called automatic discharge power) or according to the discharge power given by the staff (called manual discharge power). To avoid the energy storage system switching the discharge power back and forth, it can be set to: give priority to the maximum power and do not allow switching from high power to low power.

[0127] Correspondingly, each generator set can be controlled individually by the staff or uniformly by the PLC. When there is a cross command on the discharge power of the generator set (when the discharge power issued by the staff conflicts with the power generation power determined by the PLC), the operation of the generator set should be controlled with the maximum power between the discharge power issued by the staff and the power generation power determined by the PLC to implement the maximum power priority principle. It cannot simply rely on the discharge power instruction sent by the PLC.

[0128] The PLC monitors the actual temperature of the generator set in real time. When the actual temperature of the generator set is greater than the safety temperature threshold, it can be considered that the generator set is in an emergency state. At this time, the uncontrollable energy storage system is controlled to operate at the emergency discharge power to reduce the output power of the generator set.

[0129] This embodiment also provides protection against generator set overload and reverse power. These protections include: When load power fluctuates significantly, the PLC program automatically intervenes. When the generator set's power exceeds the upper power limits A1 / A2 / An (different protection levels set manually), the energy storage system's discharge power is sequentially increased until all energy storage systems reach maximum power. When the generator set's power falls below the lower power limits B1 / B2 / Bn (different protection levels set manually), the energy storage system's discharge power is sequentially reduced until it reaches zero.

[0130] Specifically, when the power supply demand of the load is too large, so that the fluctuation amplitude of the current power demand of the load is greater than or equal to the preset fluctuation amplitude, and the output power of the generator set is higher than the output power upper limit, the discharge power of the energy storage system is increased so that the output power of the generator set and the output power of the entire energy storage system can meet the power supply demand of the load.

[0131] When the power supply demand of the load is too small, so that the fluctuation amplitude of the current power demand of the load is greater than or equal to the preset fluctuation amplitude, and the output power of the generator set is lower than the output power lower limit, the discharge power of the energy storage system is reduced to reduce the sum of the output power of the generator set and the output power of the entire energy storage system.

[0132] This embodiment also provides SOC upper and lower limit protection: during the operation of the energy storage system, the PLC also monitors the remaining power of the energy storage system in real time, and sends a stop-discharging instruction to the energy storage system when the remaining power of the energy storage system is lower than the lower power limit and the energy storage system is in a discharging state; during the charging process of the energy storage system, when the remaining power of the energy storage system is higher than the upper power limit and the energy storage system is in a charging state, a stop-charging instruction is sent to the energy storage system, thereby preventing overcharging and over-discharging of the energy storage system.

[0133] This embodiment also provides a method for handling abnormal communication interruptions: during the process of powering the load, the PLC also monitors the communication status of the energy storage system and the generator set in real time. If communication is interrupted in the energy storage system or the generator set, the PLC controls the output power of the generator set to zero and stops the energy storage system, thereby preventing the combined power supply system of the generator set and the energy storage system from losing control.

[0134] This embodiment also provides an internal power control allocation strategy for a single energy storage system. Specifically:

[0135] The energy storage system's power control modes include remote and local. In remote mode, the energy storage system receives and distributes active power based on the difference between the load's current power demand and the generator's output power. In local mode, the energy storage system can distribute active power based on manually transmitted difference power, follow a planned curve, or use other control strategies.

[0136] Specifically, in on-site mode, while the energy storage system is operating, the PLC can determine the active power of the converter based on the energy storage system's power at its target state and the maximum charge and discharge power of the converter in the energy storage system. This allows personnel to understand the energy storage system's charge and discharge efficiency based on the converter's active power. Methods for determining the converter's active power include a proportional allocation strategy and a SOC allocation strategy.

[0137] The proportional allocation strategy is to determine the active power of the target converter based on the maximum chargeable and dischargeable power value of the target converter and the power of the energy storage system in the target state; wherein the target converter is any converter in the energy storage system.

[0138] The active power of the converter can be determined based on the following formula:

[0139]

[0140] in, is the active power of the i-th converter; is the maximum charge and discharge power value of the i-th converter; L is the number of converters; is the power of the energy storage system at the target state.

[0141] The SOC allocation strategy is to determine the active power of the target converter based on the weight ratio of the target converter, the weight ratio of the target battery stack, the sum of the weight ratios of each converter, and the power of the energy storage system in the target state; wherein, the target converter is any converter in the energy storage system; the converter and the battery stack correspond one to one; wherein, the weight ratio of the target converter is determined based on the maximum chargeable and dischargeable power value.

[0142] The active power of the converter can be determined based on the following formula:

[0143]

[0144] in, is the weight of the maximum charge and discharge power value of the converter, is the weight of the remaining power of the energy storage system battery stack, is the ratio of the maximum chargeable and dischargeable power value of the i-th converter to the maximum chargeable and dischargeable power value of all converters; when calculating the charging power target value, The difference between the remaining power of the ith battery stack and 100% is 100%. When calculating the discharge power target value, The remaining power of the i-th battery stack is 100%, that is, is the weight ratio of the target converter, is the weight ratio of the target battery stack.

[0145] It should be understood that, although the various steps in the flowcharts involved in the various embodiments described above are displayed in sequence according to the instructions of the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flowcharts involved in the various embodiments described above can include multiple steps or multiple stages, and these steps or stages are not necessarily executed and completed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0146] Based on the same inventive concept, embodiments of the present application also provide a control device for a generator set and energy storage system combined power supply system, for implementing the aforementioned control method for a generator set and energy storage system combined power supply system. The solution provided by this device is similar to the solution described in the aforementioned method. Therefore, the specific limitations of the embodiments of the control device for one or more generator set and energy storage system combined power supply systems provided below can be found in the above-mentioned limitations of the control method for a generator set and energy storage system combined power supply system, and will not be further elaborated here.

[0147] In an exemplary embodiment, Figure 4 As shown, a control device 700 for a combined power supply system of a generator set and an energy storage system is provided, comprising: a first control module 702, a first power supply adjustment module 704, an energy storage system parameter determination module 706, and a second control module 708, wherein:

[0148] The first control module 702 is configured to control the energy storage system to supply power to the load when the current power demand of the load is less than a power demand threshold.

[0149] The first power supply adjustment module 704 is used to determine the output power of the generator set based on the current power demand of the load and the output power of the energy storage system when the current power demand of the load is less than the power demand threshold when it is determined that the generator set should be put into use for power supply when the energy storage system fails to meet the power demand of the load during the power supply process.

[0150] The energy storage system parameter determination module 706 is used to determine the target state of the energy storage system and the power in the target state according to the current required power of the load and the output power of the generator set; the target state is the charging state or the discharging state.

[0151] The second control module 708 is used to control the generator set to supply power to the load according to the corresponding output power, and control the energy storage system to operate at a target state and corresponding power.

[0152] In an exemplary embodiment, when the number of energy storage systems is at least two, the energy storage system parameter determination module 706 includes: a controllable energy storage system quantity determination module, a difference power determination module, and a controllable energy storage system power determination module.

[0153] The controllable energy storage system quantity determination module is used to determine the quantity of controllable energy storage systems; a controllable energy storage system is an energy storage system that is controllable by a controller.

[0154] The differential power determination module is used to obtain the differential power according to the difference between the current required power of the load and the output power of the generator set.

[0155] The controllable energy storage system power determination module is used to obtain the power of each controllable energy storage system at the target state according to the difference power and quantity.

[0156] In an exemplary embodiment, the control device 700 of the combined power supply system of the generator set and the energy storage system further includes: an emergency processing module, an emergency discharge power determination module, and a third control module.

[0157] The emergency processing module is used to determine the preset power for the uncontrollable energy storage system when the generator set is in an emergency state; the uncontrollable energy storage system is an energy storage system that is not controllable by the controller.

[0158] The emergency discharge power determination module is used to determine the maximum value between the preset power and the power in the target state as the emergency discharge power of the uncontrollable energy storage system.

[0159] The third control module is used to control the uncontrollable energy storage system to operate at an emergency discharge power.

[0160] In an exemplary embodiment, the target state is a discharge state, and the control device 700 of the combined power supply system of the generator set and the energy storage system further includes: a first energy storage system adjustment module and a second energy storage system adjustment module.

[0161] The first adjustment module of the energy storage system is used to increase the discharge power of the energy storage system until the maximum discharge power of the energy storage system is reached when it is monitored that the fluctuation amplitude of the current power demand of the load is greater than or equal to the preset fluctuation amplitude and the output power of the generator set is higher than the output power upper limit during the process of supplying power to the load through the generator set and the energy storage system is operating in a discharge state and at a corresponding power.

[0162] The second adjustment module of the energy storage system is used to reduce the discharge power of the energy storage system until the minimum discharge power of the energy storage system is reached when the fluctuation amplitude of the current required power of the load is greater than or equal to the preset fluctuation amplitude and the output power of the generator set is lower than the output power lower limit.

[0163] In an exemplary embodiment, the control device 700 of the combined power supply system of the generator set and the energy storage system further includes: an over-discharge prevention module and an over-charge prevention module.

[0164] The over-discharge prevention module is used to send a stop-discharge instruction to the energy storage system when the remaining power of the energy storage system is lower than the lower limit of power and the energy storage system is in a discharging state during the discharging process of the energy storage system.

[0165] The overcharge prevention module is used to send a stop charging instruction to the energy storage system when the remaining power of the energy storage system is higher than the upper limit of power and the energy storage system is in a charging state during the charging process of the energy storage system.

[0166] In an exemplary embodiment, the control device 700 of the power supply system of the generator set and the energy storage system further includes: a converter active power determination module.

[0167] The converter active power determination module is used to determine the active power of the converter according to the power of the energy storage system in the target state and the maximum chargeable and dischargeable power value of the converter in the energy storage system.

[0168] In an exemplary embodiment, when the energy storage system includes at least two converters, the control device 700 of the power supply system of the generator set and the energy storage system further includes: a first operation module.

[0169] The first operation module is used to determine the active power of the target converter according to the maximum chargeable and dischargeable power value distribution ratio of the target converter and the power of the energy storage system in the target state; wherein the target converter is any converter in the energy storage system.

[0170] In an exemplary embodiment, when the energy storage system includes at least two converters and at least two battery stacks, the control device 700 of the combined power supply system of the generator set and the energy storage system further includes: a second operation module.

[0171] The second operation module is used to determine the active power of the target converter based on the weight ratio of the target converter, the weight ratio of the target battery stack, the sum of the weight ratios of each converter, and the power of the energy storage system in the target state; wherein, the target converter is any converter in the energy storage system; the converter and the battery stack correspond one to one; wherein, the weight ratio of the target converter is determined based on the maximum chargeable and dischargeable power value.

[0172] In an exemplary embodiment, the control device 700 of the power supply system of the generator set and the energy storage system further includes: a second power supply adjustment module.

[0173] The second power supply adjustment module is used to monitor that the energy storage system fails to meet the power supply demand of the load during the power supply process. If it is determined that the number of energy storage systems needs to be increased, the output power of each energy storage system is re-determined based on the current power demand of the load and the number of energy storage systems.

[0174] Each module in the control device for the combined power supply system of a generator set and energy storage system can be implemented in whole or in part through software, hardware, or a combination thereof. Each module can be embedded in or independent of a processor in a computer device in hardware form, or stored in a computer device memory in software form, so that the processor can call and execute the corresponding operations of each module.

[0175] In an exemplary embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as shown in FIG. Figure 8 As shown. The computer device includes a processor, memory, an input / output interface, a communication interface, a display unit, and an input device. The processor, memory, and input / output interface are connected via a system bus, and the communication interface, display unit, and input device are connected to the system bus via the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and external devices. The communication interface of the computer device is used to communicate with external terminals via wired or wireless communication, and the wireless communication can be achieved via Wi-Fi, a mobile cellular network, near-field communication (NFC), or other technologies. When executed by the processor, the computer program implements a control method for a combined power supply system of a generator set and an energy storage system. The display unit of the computer device is used to produce a visual image and can be a display screen, a projection device, or a virtual reality imaging device. The display screen can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covering the display screen, or a button, trackball or touchpad set on the computer device casing, or an external keyboard, touchpad or mouse.

[0176] Those skilled in the art will understand that Figure 8 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0177] In an exemplary embodiment, a computer device is provided, including a memory and a processor, wherein a computer program is stored in the memory and the processor executes the steps of any of the above-mentioned methods for controlling a power supply system jointly supplied by a generator set and an energy storage system.

[0178] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of any method of the control method of the combined power supply system of the generator set and the energy storage system are implemented.

[0179] In one embodiment, a computer program product is provided, comprising a computer program, which, when executed by a processor, implements the steps of any of the above-mentioned methods for controlling a power supply system in which a generator set and an energy storage system are combined.

[0180] Those skilled in the art will understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. In particular, any reference to memory, database, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The databases involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the various embodiments provided herein may be, but are not limited to, general-purpose processors, central processing units (CPUs), graphics processing units (GPUs), digital signal processors (DSPs), programmable logic devices (PLDs), quantum computing-based data processing logic devices, artificial intelligence (AI) processors, and the like.

[0181] The technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0182] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A control method for a power supply system combining a generator set and an energy storage system, characterized in that: The steps of the method are executed by a controller, and the method includes: When the current power demand of the load is less than the power demand threshold, controlling the energy storage system to supply power to the load; During the power supply process, when it is monitored that the energy storage system fails to meet the power supply demand of the load, if it is determined that the generator set is to be put into use for power supply, the output power of the generator set is determined based on the current power demand of the load and the output power of the energy storage system when the current power demand of the load is less than the power demand threshold; Determining a target state of the energy storage system and the power at the target state based on the current power demand of the load and the output power of the generator set; the target state is a charging state or a discharging state; The generator set is controlled to supply power to the load according to the corresponding output power, and the energy storage system is controlled to operate at a target state and corresponding power.

2. The method according to claim 1, characterized in that When there are at least two energy storage systems, determining the power of the energy storage system at the target state according to the current required power of the load and the output power of the generator set includes: Determining the number of controllable energy storage systems; the controllable energy storage system is an energy storage system controllable by a controller; Obtaining a differential power according to a difference between the current power demand of the load and the output power of the generator set; The power of each of the controllable energy storage systems in the target state is obtained according to the difference power and the quantity.

3. The method according to claim 1, characterized in that After controlling the generator set to supply power to the load according to the corresponding output power, the method further includes: When the generator set is in an emergency state, determining a preset power for an uncontrollable energy storage system; the uncontrollable energy storage system is an energy storage system that is not controllable by a controller; Determining the maximum value between the preset power and the power in the target state as the emergency discharge power of the uncontrollable energy storage system; The uncontrollable energy storage system is controlled to operate at an emergency discharge power.

4. The method according to claim 1, wherein The target state is a discharging state, and the method further includes: During the process of the generator set supplying power to the load and the energy storage system operating in a discharging state and at a corresponding power, when it is monitored that the fluctuation amplitude of the current power demand of the load is greater than or equal to a preset fluctuation amplitude, and the output power of the generator set is higher than an upper limit of the output power, the discharge power of the energy storage system is increased until the maximum discharge power of the energy storage system is reached; When the fluctuation amplitude of the current required power of the load is greater than or equal to the preset fluctuation amplitude and the output power of the generator set is lower than the output power lower limit, the discharge power of the energy storage system is reduced until the minimum discharge power of the energy storage system is reached.

5. The method according to claim 1, wherein The method further comprises: During the discharging process of the energy storage system, when the remaining power of the energy storage system is lower than the lower power limit and the energy storage system is in the discharging state, sending a stop discharging instruction to the energy storage system; During the charging process of the energy storage system, when the remaining power of the energy storage system is higher than the upper power limit and the energy storage system is in the charging state, a stop charging instruction is sent to the energy storage system.

6. The method according to claim 1, characterized in that The method further comprises: The active power of the converter is determined according to the power of the energy storage system in the target state and the maximum chargeable and dischargeable power value of the converter in the energy storage system.

7. The method according to claim 6, characterized in that In a case where the energy storage system includes at least two converters, determining the active power of the converter according to the power of the energy storage system in the target state and the maximum chargeable and dischargeable power value of the converter in the energy storage system includes: The active power of the target converter is determined according to the maximum chargeable and dischargeable power distribution ratio of the target converter and the power of the energy storage system in the target state; wherein the target converter is any converter in the energy storage system.

8. The method according to claim 6, characterized in that In a case where the energy storage system includes at least two converters and at least two battery stacks, determining the active power of the converter according to the power of the energy storage system in the target state and the maximum chargeable and dischargeable power value of the converter in the energy storage system includes: The active power of the target converter is determined based on the weight ratio of the target converter, the weight ratio of the target battery stack, the sum of the weight ratios of each converter, and the power of the energy storage system in the target state; wherein, the target converter is any converter in the energy storage system; the converter and the battery stack correspond one to one; wherein, the weight ratio of the target converter is determined based on the maximum chargeable and dischargeable power value.

9. The method according to claim 1, characterized in that The method further comprises: During the power supply process, when it is monitored that the energy storage system fails to meet the power supply demand of the load, if it is determined to increase the number of the energy storage systems, the output power of each energy storage system is re-determined based on the current power demand of the load and the number of the energy storage systems.

10. A power supply system combining a generator set and an energy storage system, characterized in that: include: Generator sets; Energy storage systems; A controller, wherein the controller is respectively connected to the generator set, the energy storage system and the load; the controller is used to execute the steps of the method according to any one of claims 1 to 8.

Images