Energy storage system power supply regulation method and system

Abstract

The application belongs to the technical field of energy storage power supply, and discloses an energy storage system power supply regulation method and system. The method comprises the following steps: obtaining the bus current change rate signal of the energy storage cabinet DC bus and integrating the bus current change rate signal to obtain an arc judgment voltage signal; comparing the arc judgment voltage signal with a preset arc judgment voltage threshold in an arc comparison unit, and outputting an emergency switching trigger signal when the preset arc judgment condition is met; outputting the emergency switching trigger signal to the energy storage cabinet fault isolation solid-state switch connected between the energy storage cabinet power input end and the load output end, starting the standby power supply access circuit, and preventing the controller from conducting control on the conduction of the switching path corresponding to the energy storage cabinet power supply; receiving the emergency switching state signal and performing recovery control when the controller is normal, and maintaining the continuous power supply of the standby power supply to the load output end when the controller fails. The application improves the reliability and extreme working condition applicability of the energy storage system fire load power supply.

Description

Technical Field

[0001] This invention relates to the field of energy storage power supply technology, and more specifically, to a method and system for regulating the power supply of an energy storage system. Background Technology

[0002] In energy storage power supply systems, the DC bus of the energy storage cabinet may experience arcing due to battery thermal runaway, accompanied by a strong electromagnetic pulse with a nanosecond-level rising edge. This strong electromagnetic pulse, through spatial coupling, can cause destructive interference to nearby low-voltage control circuits within microseconds, leading to controller failure. Under such extreme conditions, existing energy storage system power supply regulation technologies have the following drawbacks:

[0003] First, existing technology assumes the controller is always in normal working condition and does not consider the possibility of the controller itself being destroyed by electric arc electromagnetic pulses. Therefore, it lacks a hardware-level backup protection mechanism independent of the controller. When the controller fails, even if the backup power supply is intact, it cannot be connected to the load, resulting in a power outage for the fire protection load.

[0004] Secondly, existing technologies rely entirely on software commands issued by the controller for power switching control, with no physical isolation or hardware-level bypass between the switching path and the controller. When the controller fails due to electromagnetic interference or the drive signal transmission link is interrupted, the switching action cannot be performed, and the faulty bus cannot be disconnected in a timely manner.

[0005] Furthermore, existing power switching decisions are typically based on a single voltage threshold or fixed priority, lacking a dynamic assessment mechanism for the power supply's own health status. This makes it difficult to perform preventative switching in advance when power quality deteriorates but has not yet completely failed. Additionally, there is a lack of verification feedback loops after switching, making it impossible to initiate remedial measures when switching fails.

[0006] In summary, the root cause of the problems with existing technologies lies in the fact that the switching control process relies entirely on the controller, which itself may fail under arcing or electromagnetic pulse environments. Furthermore, the lack of continuous data transmission and closed-loop feedback between processing stages prevents effective coordinated protection in the event of controller failure. Therefore, how to reliably disconnect the faulty bus and reliably connect the backup power supply under extreme conditions where the controller may fail, while ensuring the integrity and verifiability of the switching process, is a pressing technical problem that needs to be solved in this field.

[0007] In view of this, the present invention proposes a power supply regulation method and system for energy storage systems to solve the above problems. Summary of the Invention

[0008] To address the shortcomings of existing technologies, the present invention aims to provide a power supply regulation method and system for an energy storage system. This method involves acquiring the bus current change rate signal from the DC bus of the energy storage cabinet and integrating it to obtain an arc detection voltage signal. An energy storage sustaining unit, powered by energy extracted from the DC bus of the energy storage cabinet, maintains the operation of the arc comparison unit. When the arc detection voltage signal meets preset arc detection conditions, an emergency switching trigger signal is output. This emergency switching trigger signal, on the one hand, turns off the energy storage cabinet fault isolation solid-state switch connected in series between the input terminal of the DC bus and the load output terminal, thus cutting off the faulty branch of the energy storage cabinet; on the other hand, it activates the backup power supply through a hard-wired trigger path. The system inputs the circuit and latches the drive enable signal of the energy storage cabinet's power supply branch through hardware blocking path. When no emergency switching trigger signal is output and the controller is normal, it performs routine power supply selection, switching preparation, switching verification, and software emergency switching based on the power supply health index of the mains power, energy storage cabinet, and UPS. Thus, when the controller is normal, it achieves fine-grained switching management of multiple power supplies. When the controller fails due to strong electromagnetic interference, it can still cut off the faulty branch of the energy storage cabinet and connect the backup power supply through the energy storage cabinet fault isolation solid-state switch, the backup power supply access circuit, and the hardware blocking path blocking action, thereby improving the reliability of the load power supply of the energy storage system and its applicability to extreme working conditions.

[0009] This invention provides the following technical solution: a power supply regulation method for an energy storage system, comprising:

[0010] The bus current change rate signal of the DC bus of the energy storage cabinet is acquired, and the bus current change rate signal is integrated to obtain the arc determination voltage signal.

[0011] The energy storage and maintenance unit, which draws power from the DC bus of the energy storage cabinet, supplies power to the arc comparison unit. The arc comparison unit compares the arc judgment voltage signal with the preset arc judgment voltage threshold. When the preset arc judgment condition is met, an emergency switching trigger signal is output.

[0012] An emergency switching trigger signal is output to the energy storage cabinet fault isolation solid-state switch connected in series between the DC bus input terminal and the load output terminal of the energy storage cabinet, causing the energy storage cabinet fault isolation solid-state switch to switch from the on state to the off state, thereby cutting off the power supply path from the DC bus input terminal of the energy storage cabinet to the load output terminal; based on the emergency switching trigger signal, the backup power supply access circuit is activated through the hard-wired trigger path, so that the backup power supply is connected to the load output terminal; and the controller is prevented from controlling the conduction of the corresponding switching path of the energy storage cabinet power supply through the hardware blocking path, and the emergency switching status signal is output by the backup power supply access circuit or the hardware blocking path.

[0013] When the controller is functioning normally, it receives an emergency switching status signal and performs recovery control. When the controller fails, the backup power supply circuit maintains the continuity between the backup power supply and the load output terminal, so that the backup power supply continuously supplies power to the load output terminal.

[0014] A power supply control system for an energy storage system, comprising implementing the power supply control method for an energy storage system, including:

[0015] Data acquisition module: acquires the bus current change rate signal of the DC bus of the energy storage cabinet, and integrates the bus current change rate signal to obtain the arc determination voltage signal;

[0016] Signal Comparison Module: The arc comparison unit is powered by the energy storage and maintenance unit that draws power from the DC bus of the energy storage cabinet. The arc comparison unit compares the arc judgment voltage signal with the preset arc judgment voltage threshold. When the preset arc judgment condition is met, an emergency switching trigger signal is output.

[0017] Power switching module: Outputs an emergency switching trigger signal to the energy storage cabinet fault isolation solid-state switch connected in series between the DC bus input terminal and the load output terminal of the energy storage cabinet, causing the energy storage cabinet fault isolation solid-state switch to switch from the on state to the off state, thereby cutting off the power supply path from the DC bus input terminal of the energy storage cabinet to the load output terminal; Based on the emergency switching trigger signal, it starts the backup power supply access circuit through a hard-wired trigger path, so that the backup power supply is connected to the load output terminal; It also prevents the controller from controlling the conduction of the corresponding switching path of the energy storage cabinet power supply through a hardware blocking path, and outputs an emergency switching status signal from the backup power supply access circuit or the hardware blocking path;

[0018] Switching control module: When the controller is normal, the controller receives the emergency switching status signal and executes recovery control. When the controller fails, the backup power supply connection circuit maintains the conduction state between the backup power supply and the load output terminal, so that the backup power supply continuously supplies power to the load output terminal.

[0019] The technical effects and advantages of the power supply regulation method and system for energy storage systems of the present invention are as follows:

[0020] 1. By acquiring and integrating the current change rate signal on the DC bus of the energy storage cabinet, an arc detection voltage signal is obtained. The arc comparison unit is powered by an energy storage sustaining unit that draws energy from the DC bus, enabling the arc detection module to operate independently without relying on the controller power supply or anti-interference protection layer. When the arc detection voltage signal meets preset conditions, an emergency switching trigger signal is directly output to a normally closed fault isolation solid-state switch connected in series between the energy storage cabinet's power input and load output terminals. This allows for the pure hardware-based shutdown of the faulty bus without relying on the controller or software logic. Simultaneously, the backup power supply connection circuit is activated via a hard-wired trigger path based on the same trigger signal, ensuring automatic backup power supply connection to the load output terminal even in the event of complete controller failure. This solves the core defect in existing technologies where controller failure equates to protection failure.

[0021] 2. By synchronously inputting the emergency switching trigger signal into the hardware blocking path, the switching drive path corresponding to the energy storage cabinet's power supply is shut down and blocked. This prevents the controller from reactivating the path before the fault is cleared, avoiding controller malfunction or reconnection of the faulty bus. When the controller is functioning normally, the emergency switching status signal output from the backup power supply access circuit or the hardware blocking path informs the controller, which then takes over subsequent power restoration. In the event of controller failure, the energy storage cabinet's fault isolation solid-state switch and backup power supply access circuit independently maintain power supply until manual intervention. This forms a dual-coordinated mechanism with hardware-level emergency protection as the primary method and controller recovery as a secondary method, improving power supply reliability under extreme conditions.

[0022] 3. When no emergency switching trigger signal is output and the controller is functioning normally, power supply data from the mains, energy storage cabinet, and UPS are collected to calculate the health index of each power supply and generate status codes. The target power supply is then determined based on preset priorities. When the target voltage is higher than the current capacitor voltage, the auxiliary switch is closed to charge the energy storage capacitor bank through a current-limiting resistor. Once the capacitor voltage reaches a preset ratio, the auxiliary switch is opened, executing a disconnect-then-connect switching sequence. The energy storage capacitor bank maintains the output voltage during the dead zone, reducing output voltage drops during switching. After switching is complete, the actual deviation between the output voltage and the target voltage is calculated and compared with a deviation threshold set based on power quality sag standards. A switching success or failure flag is output, forming a closed loop of execution, verification, and correction, avoiding the problem of execution without verification in existing technologies.

[0023] 4. When the switching verification fails and no emergency switching trigger signal is output, a forced switch to an available power source is initiated based on the UPS health index and the mains power health index, completing software-level emergency recovery. In the event of an arcing event, the hardware emergency switch becomes an independent action, with higher priority than any software command. Both operate independently and complement each other, enabling the system to achieve refined management through conventional and software emergency switching when the controller is functioning normally. In the event of controller failure, the energy storage cabinet fault isolation solid-state switch shuts down, the backup power supply access circuit is activated, and hardware blocking path actions ensure basic power supply, improving the reliability of the energy storage system's fire-fighting load power supply and its applicability to extreme operating conditions.

[0024] 5. This application organizes the steps of bus current monitoring, arc detection, emergency switching triggering, backup power supply access, hardware blocking, conventional power supply selection, pre-charging, switching execution, switching verification, and software emergency switching into a continuously transmitted data processing chain, with the processing result of the previous step serving as the input basis for the next step. Switching event information is recorded in the local log and reported via the CAN bus. After an emergency switch is completed, the switching time, triggering reason, and action result are saved through an independent status register, providing a complete traceability basis for fault analysis and system maintenance. This improves upon the problems of fragmented steps and incomplete information loops in existing technologies, enabling the power supply control process to have better continuity and maintainability.

[0025] This application not only solves the problem of reliable switching of fire protection power supply in scenarios where the controller may be destroyed by electric arc electromagnetic pulse, but also significantly improves the reliability of load power supply and extreme condition applicability of energy storage system through multi-layer collaboration of hardware and software, routine and emergency, and execution and verification. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of a power supply regulation method for an energy storage system according to the present invention;

[0027] Figure 2 This is a schematic diagram of the method for making switching decisions based on decision rules and preset priorities according to the present invention;

[0028] Figure 3 A schematic diagram of the method for preparing the execution switching of the present invention;

[0029] Figure 4 This is a schematic diagram of the power supply control system structure of an energy storage system according to the present invention. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Example 1

[0032] Please see Figure 1 As shown, this embodiment provides a power supply regulation method for an energy storage system, including:

[0033] The bus current change rate signal is acquired on the DC bus of the energy storage cabinet, and the bus current change rate signal is integrated to obtain the arc determination voltage signal.

[0034] In one specific embodiment, the method for obtaining the arc determination voltage signal includes:

[0035] A Rogowski coil is installed on the DC bus of the energy storage cabinet to obtain the bus current change rate signal.

[0036] The bus current change rate signal is input to an integrator to obtain the arc detection voltage signal corresponding to the bus current change rate. The integrator includes an input resistor, an integrating capacitor, and a reset resistor connected in parallel with the integrating capacitor. The integration time constant of the integrator is determined based on the Rogowski coil mutual inductance coefficient, the rated current variation range of the DC bus of the energy storage cabinet, the allowable detection time of the arc rising edge, and the input range of the arc comparison unit. The output of the integrator is connected to a limiting circuit and a comparison input filter circuit. The limiting circuit is used to limit the arc detection voltage signal from exceeding the input range of the arc comparison unit, and the comparison input filter circuit is used to filter out single spike noise. The signal after integration, limiting, and filtering is input to the arc detection voltage signal as the arc comparison unit.

[0037] The arc comparison unit is powered by an energy storage and maintenance unit that draws power from the DC bus of the energy storage cabinet. The arc comparison unit compares the arc determination voltage signal with a preset arc determination voltage threshold. When the preset arc determination condition is met, an emergency switching trigger signal is output. The preset arc determination voltage threshold is set as follows: the arc determination voltage signal is collected under the arc-free condition of the DC bus of the energy storage cabinet to obtain an arc-free sample set, and the maximum arc-free voltage value is determined from the arc-free sample set; the arc determination voltage signal is collected under the artificial arc-drawing condition, the equivalent pulse injection condition, or the verified arc simulation condition to obtain an arc sample set, and the minimum effective arc voltage value is determined from the arc sample set; when the minimum effective arc voltage value is greater than the maximum arc-free voltage value, the preset arc determination voltage threshold is set to any value between the maximum arc-free voltage value and the minimum effective arc voltage value, preferably the midpoint between the two; when the minimum effective arc voltage value is not greater than the maximum arc-free voltage value, the integrator time constant, filter parameters, or shielding structure are adjusted and the threshold is recalibrated.

[0038] In one specific embodiment, the method for obtaining an emergency switchover trigger signal includes:

[0039] The arc determination voltage signal is input into the arc comparison unit;

[0040] The energy storage sustaining unit supplies power to the arc comparison unit;

[0041] The arc comparison unit outputs an emergency switching trigger signal based on the comparison result between the arc judgment voltage signal and the preset arc judgment conditions. Specifically, when the arc judgment voltage signal exceeds the preset arc judgment voltage threshold for N consecutive samples, an arc event is determined to have occurred, and a high level is output as the emergency switching trigger signal; otherwise, a low level is output or no trigger signal is output. Here, N is the number of consecutive samples, set as follows: Let the allowable judgment time for the arc rising edge be Ta, and the sampling period be Ts, then N satisfies N×Ts≤Ta; simultaneously, based on the arc-free electromagnetic interference test data, the maximum number of consecutive threshold-crossing pulses Nn is statistically analyzed, and N>Nn is taken; if N×Ts≤Ta and N... In the case of N > Nn, N has multiple possible values. The smallest integer that satisfies N > Nn and N × Ts ≤ Ta is taken as the number of consecutive samples N. When there is no N that simultaneously satisfies the conditions, the sampling period Ts is shortened or the filtering parameters are adjusted and N is re-determined. The method for setting the sampling period Ts includes: determining the upper limit of the first sampling period based on the highest effective frequency of the arc judgment voltage signal, determining the upper limit of the second sampling period based on the allowable judgment time of the arc rising edge and the number of consecutive samples, and taking the sampling period that is not greater than the smaller value between the upper limit of the first sampling period and the upper limit of the second sampling period as Ts, so that the arc judgment process satisfies both the signal sampling requirements and the emergency switching response time requirements.

[0042] Methods for supplying power to the arc comparison unit using an energy storage sustaining unit include:

[0043] The energy storage sustaining unit is constructed as an energy storage capacitor connected in parallel to the power supply terminal of the arc comparator unit, so that the charging energy of the energy storage capacitor is taken from the DC bus of the energy storage cabinet.

[0044] When the DC bus voltage of the energy storage cabinet is lower than the voltage of the energy storage capacitor and the unidirectional conducting device connected to the discharge branch of the energy storage capacitor is in the forward conducting state, the energy storage capacitor releases energy to maintain the operation of the arc comparison unit for at least a preset duration to complete the emergency switching trigger signal output. The preset duration is set by covering the time required for fault determination and backup power access establishment. The preset duration is determined based on the continuous sampling determination duration, the arc comparison unit output delay, the backup power access circuit trigger delay, and the hardware blocking path latch establishment delay. Specifically, the continuous sampling determination duration is N×Ts, the arc comparison unit output delay is the time required for the comparator to go from input threshold exceeding to output flipping, and the backup power access circuit trigger delay is the time required for the emergency switching trigger signal to be input to the backup power access circuit. The time required to establish the backup power supply conduction path, and the hardware blocking path latch establishment delay are the time required from the emergency switching trigger signal input latch circuit to the stable output of the blocking level; the preset maintenance period is not less than the sum of the continuous sampling judgment duration, the arc comparison unit output delay, the backup power supply access circuit trigger delay, and the hardware blocking path latch establishment delay; the method for setting the energy storage capacitor capacity is as follows: obtain the total operating current of the arc comparison unit, isolation driver, latch circuit, and backup power supply access trigger terminal during the emergency switching process, determine the allowable voltage drop value at the energy storage capacitor terminal, and the energy storage capacitor capacity is greater than or equal to the product of the operating current and the preset maintenance period divided by the allowable voltage drop; when the energy storage capacitor also needs to cover the requirements of status signal maintenance or repeated triggering, the capacity margin is increased based on the above capacity.

[0045] An emergency switching trigger signal is output to the energy storage cabinet fault isolation solid-state switch connected in series between the DC bus input terminal and the load output terminal of the energy storage cabinet, causing the energy storage cabinet fault isolation solid-state switch to switch from the on state to the off state, thereby cutting off the power supply path from the DC bus input terminal of the energy storage cabinet to the load output terminal; based on the emergency switching trigger signal, the backup power supply access circuit is activated through the hard-wired trigger path, so that the backup power supply is connected to the load output terminal; and the controller is prevented from controlling the conduction of the corresponding switching path of the energy storage cabinet power supply through the hardware blocking path, and the emergency switching status signal is output by the backup power supply access circuit or the hardware blocking path.

[0046] In one specific embodiment, the method for outputting an emergency switching trigger signal to the energy storage cabinet fault isolation solid-state switch includes:

[0047] The fault isolation solid-state switch of the energy storage cabinet is configured as a MOSFET group connected in series between the power input terminal and the load output terminal of the energy storage cabinet. The MOSFET group is controlled by a gate drive circuit that is turned on by default.

[0048] When the fault isolation solid-state switch of the energy storage cabinet does not receive an emergency switching trigger signal, the MOSFET group remains on, so that the power supply of the energy storage cabinet flows to the load output terminal through the fault isolation solid-state switch of the energy storage cabinet.

[0049] When the fault isolation solid-state switch of the energy storage cabinet receives an emergency switching trigger signal, the high-level output of the arc comparator unit controls the MOSFET group to turn off, thereby cutting off the power supply path from the DC bus input terminal of the energy storage cabinet to the load output terminal.

[0050] The methods for activating the backup power supply connection circuit based on the emergency switchover trigger signal include:

[0051] In one specific embodiment, the method of activating the backup power supply access circuit via a hard-wired trigger path based on an emergency switchover trigger signal includes:

[0052] The hard-wire trigger path includes the output of the arc comparator unit, a current-limiting resistor, a unidirectional isolation device, an isolation driver, and the trigger terminal of the backup power supply access circuit. When the emergency switching trigger signal is transmitted along the hard-wire trigger path, it bypasses the controller processing chain, the communication bus transmission chain, and the software interrupt handling process. After receiving the emergency switching trigger signal, the backup power supply access circuit closes the power switch of the backup power supply branch, thus establishing a conductive path between the backup power supply and the load output.

[0053] The hardware blocking path includes an emergency switch trigger signal input terminal, a latch circuit, a disable gate circuit, and the gate drive enable terminal of the corresponding switching path of the energy storage cabinet power supply. Upon receiving the emergency switch trigger signal, the latch circuit outputs a blocking level. The disable gate circuit, based on this blocking level, keeps the gate drive enable signal of the corresponding switching path of the energy storage cabinet power supply in an invalid state. Even if the controller re-outputs a conduction command after a fault, the conduction command is shielded by the disable gate circuit, preventing the corresponding switching path of the energy storage cabinet power supply from being re-conducted. The latch circuit only releases the blocking state upon receiving a manual reset signal.

[0054] The emergency switching trigger signal is input to the trigger terminal of the backup power supply circuit via a hard-wired trigger path; the hard-wired trigger path does not pass through the controller processing chain and the communication bus transmission chain.

[0055] The backup power supply access circuit closes the conduction path corresponding to the backup power supply based on the emergency switching trigger signal, so that the backup power supply is connected to the load output terminal.

[0056] In one specific embodiment, the method of preventing the controller from controlling the switching path of the energy storage cabinet power supply by blocking the path with hardware includes:

[0057] The emergency switch trigger signal is synchronously input into the hardware blocking path.

[0058] The switching drive path corresponding to the power supply of the energy storage cabinet is shut down and blocked by the hardware blocking path.

[0059] The blockage is maintained until the fault is cleared to prevent the controller from reconnecting the power supply to the energy storage cabinet and switching the circuit. The blockage is lifted after manual confirmation that the fault has been cleared.

[0060] When the controller is functioning normally, it receives an emergency switching status signal and performs recovery control. When the controller fails, the backup power supply circuit maintains the continuity between the backup power supply and the load output terminal, so that the backup power supply continuously supplies power to the load output terminal.

[0061] Methods for maintaining continuous power supply to the load output under both normal controller operation and controller failure conditions include:

[0062] The methods for determining the normal and fault states of the controller include: the controller operates according to a preset heartbeat cycle. Outputs a heartbeat signal and receives a drive feedback signal or a communication response signal; when the heartbeat signal is within a preset heartbeat waiting period... The controller is considered to be in normal condition when the internal updates are continuous and the drive feedback signal or communication response signal is consistent with the controller output command; when the heartbeat signal is within the preset heartbeat waiting period... If the internal data is not updated, or if the drive feedback signal or communication response signal is inconsistent with the controller output command, the controller is determined to be in a failed state.

[0063] Preset heartbeat waiting period The setting method includes: obtaining the preset heartbeat cycle of the controller's heartbeat signal. Maximum transmission delay of heartbeat signal transmission link And the maximum jitter time of the heartbeat signal under normal operating conditions. Preset heart rate waiting period satisfy ,in, The number of consecutive heartbeat cycles allowed to be lost. The settings are based on the controller's risk of misjudgment and fault identification response requirements, and It is an integer not less than 2; at the same time, a preset heartbeat waiting period is defined. Not greater than the controller failure allowable identification time Controller failure allowed identification time The time limit is determined based on the allowable power outage time of the load, the establishment time of the backup power supply, and the hardware emergency switchover response time; when there are at least two conditions that are met... When selecting values, choose those that satisfy... and The minimum value is used as the preset heartbeat waiting period; when At that time, shorten the preset heart rate cycle. Reduce the number of consecutive heartbeat cycles that can be lost. Alternatively, by improving the response speed of the heartbeat signal transmission link, the preset heartbeat waiting period can be redefined. .

[0064] When the controller is functioning normally, it receives an emergency switch status signal and performs recovery control based on the emergency switch status signal.

[0065] When the controller fails, the power supply relationship between the backup power supply and the load output is maintained. After the controller returns to normal, the controller will take over the subsequent power restoration process. When the controller fails, the backup power supply access circuit and the hardware blocking path are maintained in their current operating state by the latching circuit.

[0066] When no emergency switching trigger signal is output and the controller is in normal working condition, the normal power supply selection procedure is performed.

[0067] The standard power supply selection process includes:

[0068] Collect power supply data and calculate a power supply health index that includes the mains power health index, energy storage cabinet health index, and UPS health index based on the power supply data.

[0069] Methods for calculating the power supply health index, which includes the mains health index, energy storage cabinet health index, and UPS health index, include:

[0070] Power supply data is collected through a pre-built power supply circuit. This circuit includes three power input terminals, one output terminal, a solid-state automatic transfer switch, an energy storage capacitor bank, a controller, an anti-interference protection layer, and an emergency switching layer. Specifically, the power input terminals include a mains input terminal, a DC bus input terminal of the energy storage cabinet, and a built-in UPS output terminal. The output terminal is connected to the fire-fighting load. The solid-state automatic transfer switch consists of three back-to-back MOSFETs, each connected in series with a fast-acting fuse, controlling the on / off state of the three power supplies. The MOSFET gate drive signal is transmitted via fiber optic isolation. The energy storage capacitor bank, connected across the output terminal, consists of multiple low-ESR electrolytic capacitors connected in parallel, used to maintain the output voltage during switching. The total capacity is determined based on the load power and the maximum allowable voltage drop time. The controller includes a sampling circuit, a logic processing unit, a drive circuit, and a communication interface. Voltage sampling uses an isolated differential amplifier, and the output signal is connected to the FPGA's on-chip ADC. Current sampling uses a Hall effect sensor. The sampling rate of all sampling channels is determined based on the Nyquist sampling theorem and the system response time requirements. The anti-interference protection layer consists of the controller and sampling circuit housed in a metal shielded box. All input and output lines pass through feedthrough filters, critical signal lines use twisted-pair shielded cables, and common-mode chokes, X / Y capacitors, and transient suppression diodes are installed on the power input lines. The emergency switching layer consists of a self-powered arc detection module and a fault isolation solid-state switch for the energy storage cabinet. It is electrically isolated from the controller and does not rely on the system's main power supply or the anti-interference protection layer. Its specific structure and operation method are as described above.

[0071] Power supply data includes sampling time, mains power data, energy storage cabinet data, and UPS data; methods for collecting power supply data include:

[0072] The voltage sample value, frequency sample value, and total harmonic distortion rate of the mains input terminal are obtained in multiple consecutive sampling periods to obtain the mains status record.

[0073] The voltage, current, and current change rate of the energy storage cabinet are obtained from the DC bus input terminal of the energy storage cabinet in multiple consecutive sampling periods to obtain the energy storage cabinet status record.

[0074] The UPS status record is obtained by collecting voltage, current and battery state of charge values ​​at the UPS output terminal over multiple consecutive sampling periods.

[0075] Time alignment and unit unification are performed on each field in the above records to obtain power supply data.

[0076] The power supply health index is calculated based on power supply data, including the mains power health index, energy storage cabinet health index, and UPS health index.

[0077] Methods for calculating the power supply health index based on power supply data include:

[0078] Obtain power supply data, and extract the mains power data, energy storage cabinet data, and UPS data corresponding to the current sampling time from the power supply data.

[0079] Methods for calculating the mains power health index include:

[0080] The voltage health is calculated based on the mains voltage. Specifically, the ratio of the mains voltage to the rated voltage is calculated and marked as the first voltage ratio. The smaller value between the first voltage ratio and the value 1 is taken to obtain the voltage health.

[0081] Frequency health is calculated based on the mains frequency. Specifically, frequency health is calculated by linearly decaying the deviation of the mains frequency from the rated frequency to 0. ,in, For mains frequency, The function is to maximize the value; 50 is the rated frequency of the mains power in this embodiment, and 5 is the maximum allowable frequency deviation of the mains power in this embodiment; when the rated frequency of the applicable power supply or the allowable frequency deviation of the load is other values, replace 50 in the above formula with the corresponding rated frequency of the power supply, and replace 5 with the corresponding maximum allowable frequency deviation.

[0082] The health status of total harmonic distortion (THD) is calculated based on the THD. Specifically, the THD health status is calculated by linearly decaying the THD to 0 based on the ratio of the THD to the maximum allowable value. ,in, The total harmonic distortion (THD) is 10%, which is the maximum allowable THD in this embodiment. When the maximum allowable THD corresponding to the load's allowable input power quality requirements, the power supply's rated output quality requirements, or the applicable power supply quality standards is other values, 10% in the above formula is replaced with the corresponding maximum allowable THD. THD and the maximum allowable THD are expressed in the same way, both in percentage form or both in decimal form.

[0083] The arithmetic mean of voltage health, frequency health, and total harmonic distortion (THD) health is used as the mains health index. When the mains voltage is lower than the mains voltage threshold, or the mains frequency is lower than the first mains frequency threshold, or the mains frequency is higher than the second mains frequency threshold, the mains health index is forcibly set to 0. The mains voltage threshold, the first mains frequency threshold, and the second mains frequency threshold are all determined based on the rated input range of the load, the rated output range of the power supply, and the applicable power quality standards.

[0084] Methods for calculating the health index of energy storage cabinets include:

[0085] When the arc detection voltage signal exceeds the preset arc detection voltage threshold for multiple consecutive samplings, an arc event is determined to have occurred, and the arc risk coefficient is marked as 0; otherwise, the arc risk coefficient is marked as 1.

[0086] The health index of the energy storage cabinet is calculated based on the bus voltage and arc risk coefficient. Specifically, the health index of the energy storage cabinet is the ratio of the bus voltage to the rated voltage multiplied by the arc risk coefficient. When the bus voltage of the energy storage cabinet is lower than the rated setting value, the health index of the energy storage cabinet is forcibly set to 0. The rated setting value can be determined according to the rated input range of the load, the rated output range of the power supply, and the applicable power quality standards.

[0087] Methods for calculating the UPS Health Index include:

[0088] The normal operating range is set based on the UPS output voltage. If the UPS voltage is outside the normal operating range, or the battery state of charge (SBC) is below the SBC threshold, the UPS health index is 0; otherwise, the UPS health index is calculated based on the UPS voltage and battery SBC. Specifically, the UPS health index... ,in, This is the UPS voltage; The battery state of charge is defined as follows: The normal operating range is set according to national standards; In this example, the UPS rated output voltage is 24V; When the UPS rated output voltage is other values, the 24 in the above UPS health index formula is replaced with the corresponding UPS rated output voltage; The battery state of charge threshold is set according to the rated input range of the load, the rated output range of the power supply, and the applicable power quality standards.

[0089] The target power source is determined based on the power supply health index. When the target power source is different from the current power source, a switching preparation is performed. After the switching preparation is completed, the switching strategy of connecting to the target power source is executed.

[0090] In one specific implementation, the method for determining the target power supply based on the power supply health index includes:

[0091] After comparing the mains power health index, energy storage cabinet health index, and UPS health index with their respective preset thresholds, a three-bit binary status code S=[s1,s2,s3] is obtained for each power source. Here, s1, s2, and s3 correspond to the status values ​​of the mains power, energy storage cabinet, and UPS health indices, respectively. A status code of 1 indicates that the corresponding health index is not lower than the preset threshold, while a status code of 0 indicates that the corresponding health index is lower than the preset threshold. The preset thresholds are set as follows: based on the minimum power supply requirements of the fire load, determine the minimum health indices corresponding to the mains power, energy storage cabinet, and UPS that can meet the requirements for continuous power supply, voltage stability, and switching response for the load. The maximum value among the minimum health indices corresponding to each power source is taken as the corresponding preset threshold. If the power supply constraints for different power source types differ significantly, separate thresholds can be set for the mains power, energy storage cabinet, and UPS, and compared with the corresponding power source health indices. The preset thresholds should ensure that power sources with a status code of 1 can meet the minimum power supply requirements of the load, and power sources with a status code of 0 should not be prioritized for connection to the target power source.

[0092] When at least one status code is 1, the target power supply is selected from the power supplies with status code 1 according to the preset priority.

[0093] The preset priorities are: mains power priority 1 > energy storage cabinet priority 2 > UPS priority 3.

[0094] Reference Figure 2 The method for selecting a target power supply from power supplies with status code 1 according to preset priority includes:

[0095] If the current mains power supply is AC power and s1=1, maintain the current power supply.

[0096] If the current main power supply is AC power and s1=0, then check s2 and S3 in sequence: if s2=1, determine that the energy storage cabinet power supply is the target power supply; if s2=0 and s3=1, determine that the UPS is the target power supply; when s2=0 and s3=0, maintain the current power supply and output a critical alarm.

[0097] If the current main power supply is the energy storage cabinet and s2=1, and the mains power status code s1=0, then the energy storage cabinet will continue to supply power.

[0098] If the current main power supply is the energy storage cabinet and s2=0, then when s1=1, the mains power is determined as the target power supply; when s1=0 and s3=1, the UPS is determined as the target power supply; when s1=0 and s3=0, the current power supply is maintained and a serious alarm is output.

[0099] If the current main power supply is a UPS and s3=1, and both the mains power status code s1 and the energy storage cabinet status code s2 are 0, then the UPS power supply will be maintained.

[0100] If a higher priority power supply with status code 1 exists, then the corresponding higher priority power supply will be identified as the target power supply.

[0101] Perform a handover verification on the results of the handover strategy. If the handover fails and no emergency handover trigger signal is output, perform a software emergency handover.

[0102] In one specific implementation, refer to Figure 3 The methods for performing switchover preparation include:

[0103] The target voltage corresponding to the target power supply and the current capacitor voltage corresponding to the energy storage capacitor bank connected across the output terminal are obtained. The target voltage is the voltage sampling value of the target power supply input terminal at the current sampling time. When the target power supply is AC mains power, the target voltage is the rectified or equivalent DC side voltage, or the effective value voltage with the same dimensions as the load output terminal. The current capacitor voltage is obtained by the isolation voltage sampling circuit connected across the two ends of the energy storage capacitor bank.

[0104] When the target voltage is greater than the current capacitor voltage, the auxiliary switch of the target power supply branch is closed, and the energy storage capacitor bank is charged with limited current through the current-limiting resistor. The value of the current-limiting resistor is determined based on the RC charging time constant and the allowable peak charging current. The auxiliary switch of the target power supply branch is a component of the pre-charging circuit. The pre-charging circuit consists of a current-limiting resistor and an auxiliary switch connected in series, which is then connected across the target power input terminal and the positive terminal of the energy storage capacitor bank. Its function is to close the auxiliary switch of the target power supply branch when the target voltage is higher than the current capacitor voltage, and slowly charge the energy storage capacitor bank through the current-limiting resistor, avoiding a large current surge caused by direct connection. After pre-charging is completed, the auxiliary switch of the target power supply branch is opened, and power is supplied directly through the main path of the solid-state automatic transfer switch during switching. The auxiliary switch of the target power supply branch can be a relay, a small-power MOSFET, or an IGBT, and its rated current is much smaller than that of the main path switch.

[0105] When the current capacitor voltage is not lower than a preset ratio of the target voltage, the following switching preparation is performed: the auxiliary switch of the target power supply branch is disconnected and the switching result is output; the preset ratio is set by: obtaining the target voltage and the switching allowable voltage difference corresponding to the target power supply, calculating the difference between the target voltage and the switching allowable voltage difference and dividing it by the target voltage to obtain the preset ratio; when the current capacitor voltage is not lower than the product of the preset ratio and the target voltage, and the absolute value of the voltage difference between the current capacitor voltage and the target voltage is not greater than the switching allowable voltage difference, it is considered that the voltage difference between the energy storage capacitor bank and the target power supply is not greater than the switching allowable voltage difference, and the switching result is output; the switching allowable voltage difference is determined based on the load allowable voltage drop amplitude, the inrush current limit at the moment the target conduction group is turned on, the reverse current limit, and the capacity of the energy storage capacitor bank.

[0106] When the target voltage is not greater than the current capacitor voltage, determine whether the absolute value of the voltage difference between the current capacitor voltage and the target voltage is not greater than the allowable switching voltage difference; if it is not greater than the allowable switching voltage difference, perform the following switching preparation: directly output the allowable switching result; if it is greater than the allowable switching voltage difference, do not output the allowable switching result and maintain the current power supply state.

[0107] After completing the above switching preparations, anti-interference measures can be implemented. Methods for anti-interference include:

[0108] The output voltage sampling channel, output current sampling channel, and target power supply voltage sampling channel are designated as critical sampling channels. A primary sampling channel and a redundant sampling channel are set for each critical sampling channel. The sampled values ​​of the primary and redundant sampling channels are compared. When the difference between the sampled values ​​of the primary and redundant sampling channels is not greater than the channel consistency threshold, the corresponding critical sampling channel is determined to be consistent. A moving average filter is applied to the sampled values ​​of the critical sampling channels. When no limit jump occurs in the output after M consecutive filtering cycles, and all critical sampling channels are determined to be consistent, an anti-interference ready signal is output. The channel consistency threshold is determined based on the sampling circuit accuracy, sensor error, and allowable measurement error. M is determined based on the sampling period and the allowable waiting time for switching preparation.

[0109] Perform a handover verification on the results of the handover strategy. If the handover fails and no emergency handover trigger signal is output, perform a software emergency handover.

[0110] In one specific implementation, the method for executing the handover strategy corresponding to the handover decision includes:

[0111] The controller continuously monitors whether a switchover permission is obtained. If so, the switchover is allowed; otherwise, the controller maintains its current state and continues to wait.

[0112] A drive signal transmission path is constructed. The controller outputs a TTL level drive signal to the fiber optic transmitter, which converts it into an optical signal. The signal is then transmitted through a plastic optical fiber to the fiber optic receiver, where it is converted back to a TTL level. The receiver output is fed into a high-speed optocoupler to achieve electrical isolation between the low-voltage control circuit and the high-voltage power circuit and to provide gate drive current. The optocoupler output is connected to the MOSFET gate.

[0113] Execute the disconnect-before-connect switching sequence to ensure that no circulating current is formed between different power supplies.

[0114] The controller invalidates the drive signal corresponding to the current conduction group and turns off the current conduction group; it enters the dead zone stage. After the dead zone ends, the controller invalidates the drive signal corresponding to the target conduction group and closes the target conduction group.

[0115] Dead time is determined based on the maximum turn-off time of the MOSFETs in the current conduction group, the maximum delay of the drive transmission link, and the sampling synchronization error. Dead time is greater than or equal to the sum of the maximum turn-off time of the MOSFETs in the current conduction group, the maximum delay of the drive transmission link, and the sampling synchronization error. When there are situations where device aging or temperature rise causes changes in turn-off time, the maximum turn-off time of the MOSFETs in the current conduction group is determined based on the maximum turn-off time in the device datasheet or the measured maximum turn-off time.

[0116] During the dead time, the load is maintained by the energy storage capacitor bank; the capacity of the energy storage capacitor bank is based on the load power. Dead time Output rated voltage and allowable voltage drop value The capacity of the energy storage capacitor bank is determined by calculation. satisfy .

[0117] After the target power supply is turned on, the controller waits for the output voltage to stabilize. The method for determining output voltage stability includes: sampling the output voltage for M consecutive sampling cycles; when the change between two adjacent output voltage samples is not greater than a stable change threshold, and the deviation between the output voltage and the target voltage is not greater than a preset deviation threshold, the output voltage is considered stable. The stable change threshold is determined based on the allowable voltage fluctuation amplitude of the load and the sampling resolution; M is determined based on the time constant formed by the output filter capacitor and the load.

[0118] Perform a handover verification on the results of the handover strategy. If the handover fails and no emergency handover trigger signal is output, perform a software emergency handover.

[0119] In one specific implementation, the method for verifying the result of executing the switching strategy includes:

[0120] After the switching strategy is executed, the output voltage and output current are collected.

[0121] The actual voltage deviation is calculated based on the output voltage and the target voltage; specifically, the ratio of the absolute value of the difference between the output voltage and the target voltage to the target voltage is calculated to obtain the actual voltage deviation.

[0122] The actual voltage deviation is compared with a preset deviation threshold. If the actual voltage deviation is lower than the preset deviation threshold, the switching is considered successful; if the actual voltage deviation is not lower than the preset deviation threshold, the switching is considered unsuccessful. The preset deviation threshold is set as follows: obtain the allowable input voltage deviation of the load, the steady-state output voltage error of the target power supply, and the measurement error of the sampling circuit; subtract the steady-state output voltage error of the target power supply and the measurement error of the sampling circuit from the allowable input voltage deviation of the load to obtain a deviation margin that can be used for switching verification; use this deviation margin as the preset deviation threshold, or use a value smaller than the deviation margin as the preset deviation threshold; the preset deviation threshold should ensure that when the actual voltage deviation is lower than the preset deviation threshold, the voltage at the load output terminal is still within the allowable operating range of the fire-fighting load.

[0123] Record the switching event and enter the switching event information into the local log. The switching event information should include at least the timestamp, source power type, target power type, emergency switching trigger status, hardware block status, switching success flag, and actual voltage deviation value.

[0124] The switching events are reported to the energy storage system monitoring unit or the fire load power supply monitoring platform via the CAN bus for fault tracing and maintenance diagnosis.

[0125] Emergency handover strategies include software emergency handover strategies and hardware emergency handover strategies; methods for executing software emergency handover when handover fails and no emergency handover trigger signal is output include:

[0126] When the UPS health index is not lower than the preset threshold, the system will force a switch to the UPS.

[0127] If the UPS health index is lower than the preset threshold, the mains power health index is obtained; if the mains power health index is not lower than the preset threshold, the system is forced to switch to mains power.

[0128] If both the UPS health index and the mains health index are lower than the preset threshold, the current power supply will be maintained and a fault alarm will be output.

[0129] Control based on hardware emergency switching strategies constitutes the emergency switching layer action flow, which, together with software emergency switching strategies, forms a dual protection. Methods for coordinated control combining emergency switching strategies include:

[0130] When no emergency switchover trigger signal is output and the controller is functioning normally, the conventional power supply selection process operates in parallel with the emergency switchover layer. When no emergency switchover trigger signal is output and the controller is functioning normally, the conventional power supply selection process uses a solid-state automatic transfer switch to select between mains power, energy storage cabinet, or UPS to supply power to the load output. Specifically, an energy storage cabinet fault isolation solid-state switch is connected in series in the energy storage cabinet power supply branch. This switch remains conductive when no emergency switchover trigger signal is received, thus not affecting the normal control of the energy storage cabinet branch by the conventional power supply selection process.

[0131] When the arc comparison unit outputs an emergency switching trigger signal, the energy storage cabinet fault isolation solid-state switch turns off, cutting off the power supply path from the DC bus input terminal to the load output terminal of the energy storage cabinet. At the same time, the backup power supply access circuit connects to the backup power supply through a hard-wired trigger path, and the hardware blocking path blocks the drive enable signal of the energy storage cabinet power supply branch. The actions of turning off the energy storage cabinet fault isolation solid-state switch, starting the backup power supply access circuit, and blocking the hardware blocking path do not depend on the controller's calculation and processing results, and their priority is higher than the conventional power supply selection steps and the software emergency switching steps.

[0132] When the emergency switchover layer is activated, it notifies the controller via a hard-wired status signal line. If the controller is functioning normally, it takes over the subsequent power restoration, such as transferring the load to the backup power supply and recording the event log. If the controller has failed, the load is continuously powered by the backup power supply after the emergency switchover until manual intervention is required.

[0133] The emergency switching layer has a higher priority than any normal command. Its trigger signal directly blocks the control of the solid-state automatic switching switch corresponding to the energy storage cabinet power supply through hardware logic, ensuring that the faulty bus is reliably disconnected.

[0134] After an emergency switch is completed, the system saves information such as the switch time, triggering reason, and action result through an independent status register.

[0135] After the energy storage cabinet fault is manually confirmed to be resolved, the latching state of the hardware blocking path is released by manually resetting the signal, and the fault isolation solid-state switch of the energy storage cabinet is restored to the default conduction control state when it is not triggered, and the system re-enters the normal monitoring mode.

[0136] In this embodiment, the preset arc detection voltage threshold, continuous sampling number N, preset maintenance period, preset heartbeat waiting period, preset division threshold, preset ratio, preset deviation threshold, channel consistency threshold, and stable change threshold can all be determined by at least one of the following methods: sample calibration, device parameter back-calculation, load allowable operating range, and power supply specification requirements. For thresholds determined by sample calibration, normal operating condition samples and abnormal operating condition samples are first collected to determine the boundaries of normal operating condition samples and abnormal operating condition samples, and then the threshold is set between the two. For thresholds determined by device parameter back-calculation, they are determined based on device specification parameters, measured response delay, allowable voltage drop, allowable current surge, and sampling error. For thresholds determined by the load allowable operating range, they are determined based on the allowable input voltage range of the fire load, allowable power outage time, allowable switching surge, and continuous power supply requirements. The above thresholds are stored in the controller parameter area or the hardware comparison unit parameter setting terminal after being set, and are updated based on measured data during system debugging or maintenance.

[0137] Example 2

[0138] Please see Figure 4 As shown, this embodiment provides a power supply control system for an energy storage system, including:

[0139] Data acquisition module: acquires the bus current change rate signal of the DC bus of the energy storage cabinet, and integrates the bus current change rate signal to obtain the arc determination voltage signal;

[0140] Signal Comparison Module: The arc comparison unit is powered by the energy storage and maintenance unit that draws power from the DC bus of the energy storage cabinet. The arc comparison unit compares the arc judgment voltage signal with the preset arc judgment voltage threshold. When the preset arc judgment condition is met, an emergency switching trigger signal is output.

[0141] Power switching module: Outputs an emergency switching trigger signal to the energy storage cabinet fault isolation solid-state switch connected in series between the DC bus input terminal and the load output terminal of the energy storage cabinet, causing the energy storage cabinet fault isolation solid-state switch to switch from the on state to the off state, thereby cutting off the power supply path from the DC bus input terminal of the energy storage cabinet to the load output terminal; Based on the emergency switching trigger signal, it starts the backup power supply access circuit through a hard-wired trigger path, so that the backup power supply is connected to the load output terminal; It also prevents the controller from controlling the conduction of the corresponding switching path of the energy storage cabinet power supply through a hardware blocking path, and outputs an emergency switching status signal from the backup power supply access circuit or the hardware blocking path;

[0142] Switching control module: When the controller is normal, the controller receives the emergency switching status signal and executes recovery control. When the controller fails, the backup power supply connection circuit maintains the conduction state between the backup power supply and the load output terminal, so that the backup power supply continuously supplies power to the load output terminal.

[0143] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A power supply regulation method for an energy storage system, characterized in that, include: The bus current change rate signal of the DC bus of the energy storage cabinet is acquired, and the bus current change rate signal is integrated to obtain the arc determination voltage signal. The energy storage and maintenance unit, which draws power from the DC bus of the energy storage cabinet, supplies power to the arc comparison unit. The arc comparison unit compares the arc judgment voltage signal with the preset arc judgment voltage threshold. When the preset arc judgment condition is met, an emergency switching trigger signal is output. The emergency switching trigger signal is output to the fault isolation solid-state switch of the energy storage cabinet connected in series between the DC bus input terminal and the load output terminal, so that the fault isolation solid-state switch of the energy storage cabinet switches from the on state to the off state, thereby cutting off the power supply path from the DC bus input terminal of the energy storage cabinet to the load output terminal; according to the emergency switching trigger signal, the backup power supply access circuit is started through the hard-wired trigger path, so that the backup power supply is connected to the load output terminal; and the controller is prevented from controlling the conduction of the corresponding switching path of the energy storage cabinet power supply through the hardware blocking path: the emergency switching trigger signal is synchronously input into the hardware blocking path; The emergency switching trigger signal is latched by the latching circuit in the hardware blocking path, and the blocking level is output. By blocking the level, the gate drive enable signal of the corresponding switching path of the energy storage cabinet power supply is kept invalid, or the drive input of the corresponding switching path of the energy storage cabinet power supply is disabled. The lockout state is maintained until the energy storage cabinet fault is resolved, so as to prevent the controller from restoring the switching path of the energy storage cabinet power supply. After the energy storage cabinet fault is manually confirmed to be resolved, the lockout state is lifted by manual reset signal. An emergency switching status signal is output from the backup power supply circuit or the hardware blocking path. When the controller is functioning normally, it receives an emergency switching status signal and performs recovery control. When the controller fails, the backup power supply circuit maintains the continuity between the backup power supply and the load output terminal, so that the backup power supply continuously supplies power to the load output terminal.

2. The power supply regulation method for an energy storage system according to claim 1, characterized in that, Methods for outputting emergency switching trigger signals include: A Rogowski coil is installed on the DC bus of the energy storage cabinet to obtain the bus current change rate signal; The bus current change rate signal is input to the integrator to obtain the arc detection voltage signal; the arc detection voltage signal is input to the arc comparison unit; when the arc detection voltage signal exceeds the preset arc detection voltage threshold for N consecutive samplings, the arc comparison unit outputs a high level as an emergency switching trigger signal; otherwise, the arc comparison unit outputs a low level or does not output an emergency switching trigger signal.

3. The power supply regulation method for an energy storage system according to claim 1, characterized in that, Methods for supplying power to the arc comparator unit using an energy storage sustaining unit include: The energy storage sustaining unit is constructed as an energy storage capacitor connected in parallel to the power supply terminal of the arc comparator unit. The energy storage capacitor obtains charging energy from the DC bus of the energy storage cabinet through the power extraction circuit. When the DC bus voltage of the energy storage cabinet is lower than the voltage of the energy storage capacitor, and the unidirectional conducting device connected to the discharge branch of the energy storage capacitor is in the forward conducting state, the energy storage capacitor supplies power to the arc comparison unit through the discharge branch to maintain the operation of the arc comparison unit for at least the preset maintenance period.

4. The power supply regulation method for an energy storage system according to claim 1, characterized in that, Methods for outputting emergency switching trigger signals to the energy storage cabinet fault isolation solid-state switch include: The fault isolation solid-state switch of the energy storage cabinet is configured as a MOSFET group connected in series between the power input terminal and the load output terminal of the energy storage cabinet, and the MOSFET group is controlled by a gate drive circuit that is turned on by default. When the energy storage cabinet fault isolation solid-state switch does not receive an emergency switching trigger signal, the MOSFET group remains on, so that the energy storage cabinet power flows to the load output terminal through the energy storage cabinet fault isolation solid-state switch. When the fault isolation solid-state switch of the energy storage cabinet receives an emergency switching trigger signal, the high level output by the arc comparator unit controls the MOSFET group to turn off, thereby cutting off the power supply path from the DC bus input terminal of the energy storage cabinet to the load output terminal.

5. The power supply regulation method for an energy storage system according to claim 1, characterized in that, The methods for activating the backup power supply connection circuit based on the emergency switchover trigger signal include: The emergency switchover trigger signal is input to the trigger terminal of the backup power supply circuit via a hard-wired trigger path. The backup power supply access circuit closes the corresponding conduction path of the backup power supply according to the emergency switching trigger signal, so that the backup power supply is connected to the load output terminal. The backup power supply is the UPS output terminal, or at least one of the UPS output terminal and the mains input terminal.

6. The power supply regulation method for an energy storage system according to claim 1, characterized in that, Methods for maintaining continuous power supply to the load output under both normal and controller failure conditions include: The controller periodically outputs a heartbeat signal and receives drive feedback signals or communication response signals; When the heartbeat signal is continuously updated within the preset heartbeat waiting period, and the drive feedback signal or communication response signal is consistent with the controller output command, the controller is determined to be in a normal state. When the heartbeat signal is not updated within the preset heartbeat waiting period, or when the drive feedback signal or communication response signal is inconsistent with the controller output command, the controller is determined to be in a failure state. When the controller is in normal state, it receives an emergency switch status signal and performs recovery control based on the emergency switch status signal. When the controller is in a failure state, the backup power supply access circuit and the hardware blocking path are maintained in their current operating state by the latching circuit, so that the backup power supply and the load output are kept connected.

7. The power supply regulation method for an energy storage system according to claim 1, characterized in that, When no emergency switching trigger signal is output and the controller is in normal working condition, the normal power supply selection step is also included; The standard power supply selection process includes: Collect power supply data and calculate a power supply health index that includes the mains power health index, energy storage cabinet health index, and UPS health index based on the power supply data; The target power source is determined based on the power supply health index. When the target power source is different from the current power source, switching preparation is performed. After obtaining the permission to switch, the switching strategy to connect to the target power source is executed. Perform a switching verification on the results of the switching strategy, and execute a software emergency switch if the switching fails and no emergency switching trigger signal is output. The conventional power supply selection process uses a solid-state automatic transfer switch to switch between mains power, energy storage cabinet, and UPS. The emergency switch trigger signal has a higher priority than the conventional power supply selection process and the software emergency switch.

8. The power supply regulation method for an energy storage system according to claim 7, characterized in that, Methods for determining target power sources based on power supply health index include: After comparing the mains power health index, energy storage cabinet health index and UPS health index with the corresponding preset thresholds, the status code of each power supply is obtained. When the health index of the power supply is not lower than the corresponding preset threshold, the status code of the corresponding power supply is set to 1; otherwise, the status code of the corresponding power supply is set to 0. When at least one status code is 1, the target power supply is selected from the power supplies with status code 1 according to the preset priority.

9. A power supply regulation method for an energy storage system according to claim 7, characterized in that, Methods for performing handover preparation when the target power supply is different from the current power supply include: Obtain the target voltage corresponding to the target power supply, and the current capacitor voltage corresponding to the energy storage capacitor bank connected across the output terminal; When the target voltage is higher than the current capacitor voltage, close the auxiliary switch of the target power supply branch and charge the energy storage capacitor bank through the current limiting resistor. The preset ratio is determined based on the target voltage and the allowable switching voltage difference. When the current capacitor voltage is not lower than the preset ratio of the target voltage and the absolute value of the voltage difference between the current capacitor voltage and the target voltage is not greater than the allowable switching voltage difference, the auxiliary switch of the target power supply branch is disconnected and the allowable switching result is output. When the target voltage is not greater than the current capacitor voltage, and the absolute value of the voltage difference between the current capacitor voltage and the target voltage is not greater than the allowable switching voltage difference, the allowable switching result is directly output.

10. A power supply regulation method for an energy storage system according to claim 7, characterized in that, Methods for verifying the results of the switching strategy include: The output voltage is acquired after the switching strategy is executed; The actual voltage deviation is calculated based on the output voltage and the target voltage; the actual voltage deviation is the ratio of the absolute value of the difference between the output voltage and the target voltage to the target voltage. The actual voltage deviation is compared with a preset deviation threshold. If the actual voltage deviation is lower than the preset deviation threshold, the switching is considered successful. If the actual voltage deviation is not lower than the preset deviation threshold, the switching is considered unsuccessful.

11. A power supply regulation method for an energy storage system according to claim 7, characterized in that, Methods for performing a software emergency switchover when a switchover fails and no emergency switchover trigger signal is output include: When the UPS health index is not lower than the corresponding preset threshold, the UPS will be used as the software emergency target power source, and the switching preparation, disconnect-before-connect switching sequence and switching verification steps will be invoked to force a switch to the UPS. If the UPS health index is lower than the corresponding preset threshold and the mains health index is not lower than the corresponding preset threshold, the mains power will be used as the software emergency target power source, and the switching preparation, disconnect-before-connect switching sequence and switching verification steps will be invoked to force a switch to the mains power. If both the UPS health index and the mains power health index are lower than the corresponding preset threshold, the current power supply will be maintained and a fault alarm will be output. When an emergency switchover trigger signal is generated during the software emergency switchover process, the software emergency switchover is terminated, and the highest priority control result is the energy storage cabinet fault isolation solid-state switch off state, the backup power supply access circuit on state, and the hardware blockade path blockade state corresponding to the emergency switchover trigger signal.

12. A power supply control system for an energy storage system, implementing the power supply control method for an energy storage system as described in any one of claims 1-11, characterized in that, include: Data acquisition module: acquires the bus current change rate signal of the DC bus of the energy storage cabinet, and integrates the bus current change rate signal to obtain the arc determination voltage signal; Signal Comparison Module: The arc comparison unit is powered by the energy storage and maintenance unit that draws power from the DC bus of the energy storage cabinet. The arc comparison unit compares the arc judgment voltage signal with the preset arc judgment voltage threshold. When the preset arc judgment condition is met, an emergency switching trigger signal is output. Power switching module: Outputs an emergency switching trigger signal to the energy storage cabinet fault isolation solid-state switch connected in series between the DC bus input terminal and the load output terminal of the energy storage cabinet, causing the energy storage cabinet fault isolation solid-state switch to switch from the on state to the off state, thereby cutting off the power supply path from the DC bus input terminal of the energy storage cabinet to the load output terminal; Based on the emergency switching trigger signal, it starts the backup power supply access circuit through a hard-wired trigger path, so that the backup power supply is connected to the load output terminal; It also prevents the controller from controlling the conduction of the corresponding switching path of the energy storage cabinet power supply through a hardware blocking path, and outputs an emergency switching status signal from the backup power supply access circuit or the hardware blocking path; Switching control module: When the controller is normal, the controller receives the emergency switching status signal and executes recovery control. When the controller fails, the backup power supply connection circuit maintains the conduction state between the backup power supply and the load output terminal, so that the backup power supply continuously supplies power to the load output terminal.

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