Multi-motor black start power coordination method and system based on hybrid energy storage

Abstract

The invention relates to the technical field of relay protection, in particular to a multi-motor black-start power coordination method and system based on hybrid energy storage. Initializing a multi-motor black-start system based on supercapacitor energy storage and an uninterruptible power supply; after the system is initialized, the black-start process of the motor 1 is carried out, and stable operation monitoring is carried out; when the motor 1 operates stably, the black start process of the motor 2 is carried out. According to the multi-motor black-start optimization method and system based on the hybrid energy storage master-slave control mode, an uninterruptible power supply serves as a master control unit to provide voltage support, and energy stored by a supercapacitor serves as a slave control unit to quickly supplement starting current, so that organic combination of a voltage source and a current source is realized; meanwhile, UPS output amplitude limiting is dynamically adjusted according to initial starting characteristics of motors with different powers, sequential controllable starting of multiple motors is achieved by adopting a sectional starting process, and the problems that in a traditional scheme, UPS capacity configuration is too large, and the controllability of the starting process is poor are effectively solved.

Description

Technical Field

[0001] This invention relates to the technical field of relay protection, and in particular to a multi-motor black start power coordination method and system based on hybrid energy storage. Background Technology

[0002] Traditional solutions use uninterruptible power supplies (UPS) as the power source for black starting motors. In existing solutions, the UPS supplies power to the motor after the power grid is disconnected. Considering the requirement of 5 times the rated current at startup, the UPS capacity needs to be above 800kW, and the energy storage device capacity needs to be above 700Ah to meet the starting requirements of high-power motors.

[0003] Using only a UPS for black starting of a motor presents several challenges:

[0004] Firstly, it needs to withstand current surges of 5 times the rated current, requiring a large-capacity UPS, which leads to difficulties in selection, large space requirements, and high costs.

[0005] Secondly, UPS has a slow response speed and poor controllability, making it difficult to meet instantaneous high power demands;

[0006] Third, during normal operation, the UPS capacity utilization rate is low and the overall efficiency is not high. Summary of the Invention

[0007] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0008] In view of the aforementioned existing problems, the present invention is proposed.

[0009] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0010] In a first aspect, the present invention provides a multi-motor black start power coordination method based on hybrid energy storage, comprising: initializing a multi-motor black start system based on supercapacitor energy storage and uninterruptible power supply;

[0011] After initializing the system, motor 1 is identified using a pattern recognition algorithm. When the identification result is motor 1, the uninterruptible power supply (UPS) current limit is dynamically adjusted. Based on the UPS current limit, the auxiliary control of the over-storage system is initiated. Smooth transition control is performed to determine whether the auxiliary control of the over-storage system can be withdrawn. After the smooth transition control is completed, stable operation monitoring is performed.

[0012] When motor 1 is running stably, the black start process of motor 2 is performed.

[0013] As a preferred embodiment of the multi-motor black-start power coordination method based on hybrid energy storage described in this invention, wherein: the initialization of the multi-motor black-start system based on supercapacitor energy storage and uninterruptible power supply includes:

[0014] Turn on the uninterruptible power supply (UPS), start the UPS of the main control unit, set the V / f control parameters, configure the output voltage amplitude and frequency, establish the system reference voltage, close the switch, start the super-storage inverter, perform system self-test and parameter configuration, establish motor feature recognition model parameters, perform system collaborative control settings, and configure the super-storage system to standby mode.

[0015] As a preferred embodiment of the multi-motor black-start power coordination method based on hybrid energy storage described in this invention, wherein the black-start process of motor 1 includes:

[0016] Motor 1 is identified using a pattern recognition algorithm;

[0017] When the identification result is motor 1, the current limit of the uninterruptible power supply is dynamically adjusted.

[0018] Based on the uninterruptible power supply current limit, activate the auxiliary control of the over-storage system;

[0019] Perform smooth transition control to determine whether the auxiliary control of the excess storage system can be disengaged;

[0020] After the smooth transition control is completed, stable operation monitoring is performed.

[0021] As a preferred embodiment of the multi-motor black-start power coordination method based on hybrid energy storage described in this invention, the pattern recognition algorithm is expressed as:

[0022]

[0023] Among them, F i F is the current feature parameter. i1 For the feature library parameters of motor 1, w i S1 is the weighting coefficient, and S2 is the similarity evaluation index.

[0024] When S1 < ε1, it is determined to be motor 1;

[0025] Where ε1 is the first recognition threshold.

[0026] As a preferred embodiment of the multi-motor black-start power coordination method based on hybrid energy storage described in this invention, wherein: the dynamic adjustment of the uninterruptible power supply current limiting includes:

[0027] Calculate the rated d-axis current of motor 1 and rated q-axis current Represented as:

[0028]

[0029] Where k1 is the safety factor, I n1 The rated current of motor 1, The power factor angle of motor 1 is used to dynamically adjust the uninterruptible power supply current limit as follows:

[0030]

[0031] in, This refers to the d-axis current command dynamically adjusted by the UPS. This is the q-axis current command dynamically adjusted by the UPS.

[0032] As a preferred embodiment of the multi-motor black start power coordination method based on hybrid energy storage described in this invention, wherein: the auxiliary control of the start-up super-storage system includes:

[0033] The difference between the load current and the uninterruptible power supply (UPS) limit is calculated in real time and expressed as:

[0034]

[0035] Where, Δi d i represents the difference between the load current and the UPS current along the d-axis. l_d For the load d-axis current, i l_q Let Δi be the load q-axis current. q This represents the difference between the load current and the UPS current along the q-axis.

[0036] The over-storage command current is set as follows:

[0037]

[0038] in, The d-axis command current for over-storage. This is the q-axis command current for over-storage.

[0039] Real-time adjustment of the over-storage output current gain is expressed as:

[0040] G sc =f(SOC) sc )

[0041] Among them, SOC sc For the supercapacitor's state of charge, G sc According to SOC sc The calculated gain coefficient and the over-storage output command current are expressed as:

[0042]

[0043] when At that moment, the over-storage system quickly activated, providing... Electric current.

[0044] As a preferred embodiment of the multi-motor black-start power coordination method based on hybrid energy storage described in this invention, the black-start process of motor 2 includes:

[0045] After confirming that motor 1 is running stably and that the system has the capacity to start motor 2, the i-test is performed. abc The total current is used for motor 2 identification, and the incremental load current is calculated as follows:

[0046] Δi abc =i abc (t)-i abc (t-Δt)

[0047] Where Δt is the sampling time interval, Δi abc Let Δt be the total current difference after a time interval, where t is the time variable. Analyzing the incremental current characteristic parameters and comparing the incremental characteristics with the feature library of motor 2, the accurate identification of motor 2 under the operating condition of motor 1 is expressed as:

[0048]

[0049] Among them, F Δi F represents the current incremental feature parameter. i2 ε2 is the feature library parameter for motor 2, ε2 is the second recognition threshold, and S2 is the similarity evaluation index for motor 2.

[0050] Readjust the uninterruptible power supply current limit dynamically, and calculate the total rated d-axis current and total rated q-axis current required for the joint operation of motor 1 and motor 2.

[0051]

[0052] The uninterruptible power supply current limit is dynamically adjusted to a new value, expressed as:

[0053]

[0054] The secondary auxiliary start-up control of the over-storage system is performed, and the difference between the total load current and the limit of the new uninterruptible power supply is calculated in real time, expressed as:

[0055]

[0056] The new over-storage command current is set as follows:

[0057]

[0058] Considering the current SOC state of the supercapacitor, the output gain is adjusted as follows:

[0059] G sc =f(SOC) sc )

[0060] The final over-storage output command current is:

[0061]

[0062] When the starting current At that time, the over-storage system quickly restarted, providing the differential current;

[0063] Implement a second smooth transition control and monitor the trend of total load current changes. and

[0064] When the total load current Furthermore, once the operation is stable, motor 2 completes its startup and smoothly exits, with the over-storage command current smoothly decreasing to zero again. when When the over-storage system completely shuts down and enters standby mode or disconnects the switch, the uninterruptible power supply system completely takes over the load of the two motors.

[0065] Multi-motor stable operation monitoring is carried out, a multi-motor stable operation characteristic parameter library is established, and the system operation status is monitored in real time.

[0066] Secondly, the present invention provides a multi-motor black-start power coordination system based on hybrid energy storage, comprising: an initialization module for initializing a multi-motor black-start system based on supercapacitor energy storage and uninterruptible power supply;

[0067] The motor 1 starting module initializes the system, performs a black start process for motor 1, and monitors stable operation.

[0068] The motor 2 starting module performs a black start process for motor 2 when motor 1 is running stably.

[0069] Thirdly, the present invention provides an electronic device, comprising:

[0070] Memory and processor;

[0071] The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions. When the computer-executable instructions are executed by the processor, they implement the steps of a multi-motor black-start power coordination method based on hybrid energy storage.

[0072] Fourthly, the present invention provides a computer-readable storage medium storing computer-executable instructions that, when executed by a processor, implement the steps of the multi-motor black-start power coordination method based on hybrid energy storage.

[0073] Compared with existing technologies, the beneficial effects of this invention are as follows: The multi-motor black-start optimization method and system based on hybrid energy storage master-slave control mode proposed in this invention utilizes an uninterruptible power supply (UPS) as the master control unit to provide voltage support and a supercapacitor as the slave control unit to quickly replenish the starting current, thus achieving an organic combination of voltage and current sources. Simultaneously, it dynamically adjusts the UPS output limit according to the initial starting characteristics of motors with different power ratings and adopts a segmented starting process to achieve sequential and controllable starting of multiple motors, effectively solving problems such as excessively large UPS capacity and poor controllability of the starting process in traditional solutions. The proposed solution achieves reliable black starting of multiple motors with different power ratings and effective utilization of UPS system capacity, significantly improving the adaptability, flexibility, and economy of the black-start system, providing an optimized solution for multi-motor black starting in large industrial enterprises. Attached Figure Description

[0074] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0075] Figure 1 This is a flowchart illustrating the method.

[0076] Figure 2 Multi-motor black-start topology based on hybrid energy storage master-slave control mode.

[0077] Figure 3 Diagram of the main circuit and master-slave control structure of a multi-motor black start system based on super storage and UPS.

[0078] Figure 4 Block diagram of decoupled control for the voltage and current dual-loop control module of a UPS system.

[0079] Figure 5 Block diagram of decoupled control for current control module of superstorage system. Detailed Implementation

[0080] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0081] Example 1, referring to Figures 1-5 As an embodiment of the present invention, a multi-motor black-start power coordination method based on hybrid energy storage is provided, comprising:

[0082] It should be noted that the proposed multi-motor black-start optimization method and system based on hybrid energy storage master-slave control mode mainly uses a supercapacitor energy storage unit (hereinafter referred to as "supercapacitor storage") to assist an uninterruptible power supply (UPS) in black-starting multiple motors of different power. The UPS is the master control unit, employing a V / f control strategy and operating in voltage source mode to provide voltage support for the motors and the supercapacitor storage unit. The supercapacitor storage unit is the slave control unit, employing a PQ control strategy and operating in current source mode to quickly compensate for the difference between the motor load starting current and the UPS's maximum current limit.

[0083] Furthermore, such as Figure 2 The diagram shows the overall structure of a multi-motor black-start system based on a hybrid energy storage master-slave control mode. The system mainly consists of a master control unit, slave control units, a point of common coupling (PCC), multi-motor loads, and switches K and K1. The master control unit comprises an energy storage device and a V / f controller, operating in voltage source mode with a UPS as its core, providing voltage support for the system. The slave control unit comprises a supercapacitor and a PQ controller, operating in current source mode, providing additional current during startup. The point of common coupling (PCC) is the connection point between the master control unit, slave control units, and the load motors. The multi-motor load includes motor 1 and motor 2, and can be expanded to include multiple motors of different power ratings. Switch K is the grid-connected switch, and K1 is the supercapacitor system connection / disconnection switch.

[0084] It should be noted that the control relationship of this system can be expressed as follows: the main control unit (UPS) output provides stable voltage support, and V / f control ensures... The control unit (overcapacity) output provides additional current support to meet the requirements. The total load current is expressed as i l =i UPS +i sc Among them, u abc This represents the actual value of the three-phase voltage at point PCC. This indicates the three-phase voltage command value at point PCC. Indicates the command current of the over-storage system, i l Indicates the load current, i UPS Indicates the UPS output current, i sc Indicates the output current of the over-storage system. This is the maximum allowable output current of the UPS. When the load current exceeds this value, the over-storage system provides the difference.

[0085] Furthermore, such as Figure 3 As shown, L f1 C f1 These are the inductors and capacitors of the UPS system filter, respectively; L f2 C f2 These are the inductors and capacitors of the superstorage system filter, respectively; i abc u abc i labc and i scabc These are the UPS output current, PCC voltage, motor load current, and overcapacity system output current, respectively; d i q These are the d-axis and q-axis components of the UPS output current, respectively; u d u q These are the d-axis and q-axis components of the PCC voltage, respectively; i l_d i l_q These are the d-axis and q-axis components of the motor load current, respectively; i sc_d i sc_q These are the d-axis and q-axis components of the output current of the superstorage system, respectively. These are the d-axis and q-axis command voltages for the PCC, respectively. These are the d-axis and q-axis command currents of the over-storage system, respectively, and are given by the difference between the motor load current and the maximum limiting current of the UPS system.

[0086] It should be noted that the main control unit (UPS system) includes a voltage outer loop control module, a current inner loop control module, a current limiting module, and an SPWM modulation module. The voltage outer loop control module receives the command voltage and the actual voltage, and generates a current command through PI control. The current inner loop control module receives the current command and the actual current, and generates a PWM modulation signal through PI control. The current limiting module limits the UPS output current to protect the UPS from overload. The SPWM modulation module converts the control signal into a switching signal to drive the inverter.

[0087] It should be noted that the slave control unit (supercapacitor system) includes a supercapacitor command current calculation module, a current control module, and an SPWM modulation module. The supercapacitor command current calculation module calculates the difference between the load current and the UPS limiting current. The current control module controls the supercapacitor output according to the command current. The SPWM modulation module generates switching signals to control the inverter.

[0088] It should be noted that the mathematical model in system control includes a coordinate transformation mathematical model and a controller mathematical model. The transformation between the abc coordinate system and the dq coordinate system uses the Park transformation:

[0089]

[0090]

[0091] Where T is the Park transformation matrix:

[0092]

[0093] Where θ is the reference coordinate system angle, which is usually synchronized with the grid voltage. In this black start system, it is generated by the PLL (phase-locked loop) module of the UPS system of the main control unit.

[0094] The mathematical model of the voltage outer loop PI controller is as follows:

[0095]

[0096] The mathematical model of the current inner-loop PI controller is as follows:

[0097]

[0098] Where, k p_u and k i_u These are the proportional and integral coefficients of the voltage outer loop PI controller, respectively; k p_i and k i_i These are the proportional and integral coefficients of the inner-loop PI controller, respectively; ω is the system angular frequency; ωC f1 and ωL f1 This term is used for decoupling control of the d-axis and q-axis, eliminating the coupling effects between the axes; u inv_d and u inv_q These are the d-axis and q-axis components of the inverter control voltage.

[0099] The mathematical model for calculating the over-storage command current is as follows:

[0100] (when hour)

[0101] (when hour)

[0102] The start / stop logic for the superstorage system is as follows: when At that time, the over-storage system output current is activated. Otherwise, the over-storage system enters standby mode.

[0103] Figure 4 The dual-loop control structure of the UPS system is demonstrated, including an outer voltage control loop and an inner current control loop. The input to the outer voltage control loop is a voltage command. and actual voltage (u) d ,u q The deviation is calculated and a current command is generated through PI control, while ωC is added. f1 This achieves decoupling of the d-axis and q-axis, ultimately outputting the current command value. The inner current loop control input is a current command. and actual current (i d i q The deviation is calculated using PI control to generate a voltage control quantity, while ωL is added. f1 Term and voltage feedforward (u d ,u q This achieves decoupling, ultimately outputting the inverter control voltage (u). inv_d ,u inv_q ).

[0104] Figure 5 The current control module of the superstorage system was demonstrated, and its input is a current command. and actual current (i sc_d i sc_q The deviation is calculated using PI control to generate a voltage control quantity, while ωL is added. f2 Term and voltage feedforward (u d ,u q This achieves decoupling, ultimately outputting the inverter control voltage (u). inv_d ,u inv_q The current command calculation logic is as follows: and in and This is the UPS current limit value.

[0105] This application, based on the supercapacitor system's identification of motors with different power ratings, dynamically adjusts the UPS output limit value according to the motor's initial starting current. This prevents the UPS from bearing excessive power during startup, which could damage the UPS or shorten its lifespan. Figure 1 As shown, the specific implementation method is as follows:

[0106] S1: Initialize the multi-motor black start system based on over-storage and uninterruptible power supply;

[0107] System initialization first requires manually turning on the UPS, starting the main control unit UPS, setting the V / f control parameters, and configuring the output voltage amplitude U. m (i.e., the peak voltage of the three-phase voltage) and the frequency f (usually 50Hz or 60Hz) are used to establish the system reference voltage. Then close switch K1 to start the super-storage inverter, perform system self-test and parameter configuration, including setting the PI controller parameter k. p_i k i_i k p_u k i_u Configure filter parameters L f1 C f1 L f2 C f2 Initialize the parameter library P for each motor 1kW (Rated power of motor 1, in kW), P 2kW (Rated power of motor 2, in kW), I n1 (Rated current of motor 1), I n2 (Rated current of motor 2) (Motor power factor) (Motor power factor 2), etc., and establish motor feature recognition model parameters. Finally, perform system collaborative control settings, including configuring coordinate transformation parameters to ensure consistency of abc / dq transformation, and setting the UPS initial current limit to I. max (Maximum allowable current for safe operation of the UPS system), configure the over-storage system in standby mode, commanded current.

[0108] S2: After initializing the system, perform a black start process for motor 1 and monitor stable operation;

[0109] The black start process of motor 1 first starts motor 1 (assuming its power is P). 1kW ), detect load current i abc Then, motor 1 is identified, and the load current i is detected. abc Characteristic parameters such as amplitude, phase sequence, frequency characteristics, and harmonic components are used to calculate the rate of change of current. and power factor The detected parameters are compared with a preset motor feature library, and motor 1 is accurately identified using a pattern recognition algorithm. The identification formula is as follows: Where F i For the current characteristic parameters (such as current amplitude, frequency response, etc.), F i1 For the feature library parameters of motor 1, w i ε1 is the weighting coefficient (used to adjust the importance of different feature parameters), S1 is the identification threshold, and S1 is the similarity evaluation index. When S1 < ε1, it is determined to be motor 1.

[0110] Next, the UPS current limit is dynamically adjusted, and the rated d-axis current of motor 1 is calculated. and rated q-axis current Where k1 is the safety factor (usually taken as 1.0-1.2), I n1 The rated current of motor 1, The power factor of motor 1 is then dynamically adjusted, and the UPS current limit is dynamically adjusted to...

[0111] Then, auxiliary start-up control of the over-storage system is performed, and the difference between the load current and the UPS limit is calculated in real time. Set over-storage command current Real-time adjustment of over-storage output current gain G sc =f(SOC) sc ), where SOC sc For supercapacitors, the State of Charge (G) represents the percentage of maximum energy stored in the capacitor. sc According to SOC sc The calculated gain coefficient, and the final over-storage output command current are: when At that moment, the over-storage system quickly activated, providing... Electric current.

[0112] Next, smooth transition control is implemented, and the trend of load current change is monitored. and Set the smooth transition function T smooth (t)=e -t / τ Where τ is a time constant (determining the speed of smooth transition). When it is detected that motor 1 has finished starting (load current) And when the operation is stable, a smooth exit is performed, and the over-storage command current smoothly decreases to zero. when When the minimum current threshold (usually set to 1-5% of the rated current) is reached, the over-storage system completely exits and enters standby mode, or K1 is disconnected, and the UPS system completely takes over the load, providing stable voltage and current support.

[0113] Finally, stable operation monitoring was conducted, and a stable operation characteristic parameter library for motor 1 was established. steady1 (Stable operating current of motor 1), P steady1 (Stable operating power of motor 1) (Power factor of motor 1 during stable operation) and other parameters are monitored in real time to ensure stable operation of motor 1.

[0114] S3: When motor 1 is running stably, perform the black start process of motor 2.

[0115] The black start process of motor 2 first starts motor 2 (assuming its power is P). 2kW ), confirm that motor 1 is running stably, the system has the capacity to start motor 2, monitor load current changes, and detect i abc Total current. Then, motor 2 identification is performed, and the incremental load current Δi is calculated. abc =i abc (t)-i abc (t-Δt) (where Δt is the sampling time interval), analyze the incremental current characteristic parameters such as amplitude, phase sequence relationship, frequency characteristics, and harmonic components. By comparing the incremental features with the feature library of motor 2, accurate identification of motor 2 can be achieved when motor 1 is running. The identification formula is as follows: Where F Δi F represents the current incremental feature parameter. i2 ε2 is the feature library parameter for motor 2, ε2 is the recognition threshold, and S2 is the similarity evaluation index.

[0116] Next, the UPS current limit is dynamically readjusted, and the total rated d-axis current required for the combined operation of motors 1 and 2 is calculated. Total q-axis current Dynamically adjust the UPS current limit to the new value.

[0117] Then, the secondary auxiliary start-up control of the over-storage system is performed, and the difference between the total load current and the new UPS limit is calculated in real time. Set the new instruction current for over-storage. Considering the current SOC state of the supercapacitor, adjust the output gain G. sc =f(SOC) sc The final over-storage output command current is When the starting current At that time, the over-storage system quickly restarted, providing the differential current.

[0118] Next, a second smooth transition control is implemented to monitor the trend of total load current changes. and When it is detected that motor 2 has also finished starting (total load current) When the situation is stable, a smooth exit is performed, and the over-storage command current smoothly decreases to zero again. when When the over-storage system completely exits and enters standby mode or disconnects K1, the UPS system completely takes over the load of the two motors, providing stable voltage and current support.

[0119] Finally, multi-motor stable operation monitoring was performed, and a multi-motor stable operation characteristic parameter library was established. steady_total(Total current for stable operation of multiple motors), P steady_total (Total power for stable operation of multiple motors) (Total power factor for stable operation of multiple motors) etc., monitor the system's operating status in real time to ensure the stable operation of the multi-motor system, and be ready to respond to possible starting needs of the next motor at any time, repeating the above process.

[0120] By identifying motors with different power ratings and dynamically adjusting the UPS output limit value, this invention achieves a segmented startup process and sequential controllable startup of multiple motors.

[0121] The segmented startup process is implemented through segmented UPS limiting settings, with different limiting values ​​set for different motors. For motor 1, the limit value is set as follows: For motor 2, set For the common operating state, set The control logic for the over-storage replenishment current is as follows: when hour, when hour,

[0122] Sequential controllable startup is achieved through startup sequence control. Motor 1 is started first, and motor 2 is started only after it has stabilized. Simultaneously, load current is monitored in real time via dynamic current monitoring to determine the startup status. Smooth transition control ensures that the over-storage system smoothly exits after the motors have started, and the UPS takes over the load. It mainly includes four stages: Stage 1 (Motor 1 startup): Phase 2 (Motor 1 is running stably): The UPS handles the entire load; Phase 3 (Motor 2 starts): Phase 4 (Motor 2 operating stably): The UPS handles the entire load.

[0123] The key technology of this patent lies in the adoption of a hybrid energy storage master-slave control mode. The UPS, acting as the master control unit, operates in voltage source mode using a V / f control strategy, while the supercapacitor energy storage, acting as the slave control unit, operates in current source mode using a PQ control strategy. Through the following key optimization methods, efficient and reliable multi-motor black start is achieved.

[0124] Dynamic adjustment of UPS output limits is achieved by dynamically adjusting the UPS output current limit based on motor identification results and the rated parameters of different motors, thus preventing UPS overload. Multi-motor identification technology accurately identifies motors of different power ratings through current characteristic analysis, preset parameter comparison, and pattern recognition algorithms. Dynamic current output control of the supercapacitor energy storage system is based on the difference between the UPS limit and the actual load current, controlling the supercapacitor system's output current in real time. A smooth transition control strategy uses a smoothing function to achieve a smooth transition between the supercapacitor system and the UPS, avoiding system fluctuations during switching. A segmented multi-motor startup process enables multiple motors to start in stages according to a preset sequence, ensuring system stability.

[0125] These optimization methods collectively enable a segmented startup process and sequential controllable startup of multiple motors, as well as a smooth transition and coordinated operation between the UPS and supercapacitor energy storage, effectively solving problems such as excessive UPS capacity configuration and poor controllability of the startup process in traditional black start systems.

[0126] This patent includes a multi-motor black start optimization method based on a hybrid energy storage master-slave control mode, covering dynamic adjustment of UPS output limit value, multi-motor identification and sequential controllable start, dynamic current output control of supercapacitor energy storage system, control strategy for UPS and supercapacitor energy storage to work together, as well as the structure of the multi-motor black start system and the collaborative working mechanism of each component (including UPS, supercapacitor energy storage, controller, etc.) to implement these methods.

[0127] Specifically, the system includes: an adaptive current limiting algorithm based on motor identification; motor feature extraction and identification methods and sequential control strategies; real-time compensation algorithms and control methods; a collaborative operation mechanism under master-slave control mode; a collaborative working architecture including components such as UPS, supercapacitor energy storage, and controllers; a smooth switching strategy under different operating modes; and a decoupling control method between the voltage outer loop and the current inner loop.

[0128] The above protection points together constitute a highly efficient and reliable multi-motor black-start optimization method and system based on a hybrid energy storage master-slave control mode. Through the master-slave control mode, this system allows the UPS to only handle the motor's rated current, while the large current at startup is provided by the supercapacitor, preventing UPS overload damage. Simultaneously, precise control and smooth transition ensure stable system operation.

[0129] Example 2 illustrates a schematic scheme for a multi-motor black-start power coordination method based on hybrid energy storage. It should be noted that the technical solution of this multi-motor black-start power coordination system based on hybrid energy storage belongs to the same concept as the technical solution of the multi-motor black-start power coordination method based on hybrid energy storage described above. Details not described in detail in this embodiment of the multi-motor black-start power coordination system based on hybrid energy storage can be found in the description of the technical solution of the multi-motor black-start power coordination method based on hybrid energy storage described above.

[0130] This embodiment also provides a multi-motor black-start power coordination system based on hybrid energy storage, including:

[0131] Initialization module, initializes a multi-motor black start system based on supercapacitor energy storage and uninterruptible power supply;

[0132] The motor 1 starting module initializes the system, performs a black start process for motor 1, and monitors stable operation.

[0133] The motor 2 starting module performs a black start process for motor 2 when motor 1 is running stably.

[0134] This embodiment also provides an electronic device applicable to a multi-motor black-start power coordination scenario based on hybrid energy storage, comprising: a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions to implement the multi-motor black-start power coordination method based on hybrid energy storage as proposed in the above embodiment.

[0135] This embodiment also provides a storage medium storing a computer program that, when executed by a processor, implements a multi-motor black-start power coordination method based on hybrid energy storage as proposed in the above embodiments.

[0136] The storage medium proposed in this embodiment belongs to the same inventive concept as the multi-motor black start power coordination method based on hybrid energy storage proposed in the above embodiments. Technical details not described in detail in this embodiment can be found in the above embodiments, and this embodiment has the same beneficial effects as the above embodiments.

[0137] Based on the above description of the implementation methods, those skilled in the art can clearly understand that the present invention can be implemented using software and necessary general-purpose hardware, and of course, it can also be implemented using hardware. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk, or optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods of the various embodiments of the present invention.

[0138] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A hybrid energy storage based multi-motor black start power coordination method, characterized in that, include: Initialize a multi-motor black start system based on supercapacitor energy storage and uninterruptible power supply; After initializing the system, motor 1 is identified using a pattern recognition algorithm. When the identification result is motor 1, the uninterruptible power supply (UPS) current limit is dynamically adjusted. Based on the UPS current limit, the auxiliary control of the over-storage system is initiated. Smooth transition control is performed to determine whether the auxiliary control of the over-storage system can be withdrawn. After the smooth transition control is completed, stable operation monitoring is performed. When motor 1 is running stably, the black start process of motor 2 is performed.

2. The hybrid energy storage based multi-motor black start power coordination method according to claim 1, wherein, The initialization of the multi-motor black-start system based on supercapacitor energy storage and uninterruptible power supply includes: Turn on the uninterruptible power supply (UPS), start the UPS of the main control unit, set the V / f control parameters, configure the output voltage amplitude and frequency, establish the system reference voltage, close the switch, start the super-storage inverter, perform system self-test and parameter configuration, establish motor feature recognition model parameters, perform system collaborative control settings, and configure the super-storage system to standby mode.

3. The hybrid energy storage based multi-motor black start power coordination method according to claim 2, wherein, The pattern recognition algorithm is expressed as follows: Wherein, F i is the current feature parameter, F i1 is the motor 1 feature library parameter, w i is the weight coefficient, and S1 is the similarity evaluation index. When S1 < ε1, it is determined to be motor 1; Where ε1 is the first recognition threshold.

4. The hybrid energy storage based multi-motor black start power coordination method of claim 3, wherein, The dynamic adjustment of the uninterruptible power supply current limit includes: The rated d-axis current of the electrical machine 1 is calculated and the rated q-axis current of the electrical machine 1 is represented as: wherein k1 is a safety factor of the motor 1, I n1 is the rated current of the motor 1, is the power factor angle of the motor 1, the uninterruptible power supply current is dynamically adjusted as: wherein, respectively represent the current limiting values of the d-axis and q-axis after the adjustment of the uninterruptible power supply.

5. The hybrid energy storage based multi-motor black start power coordination method according to claim 4, wherein, The auxiliary control for starting the super-storage system includes: The difference between the load current and the uninterruptible power supply (UPS) limit is calculated in real time and expressed as: where Δi d is the difference between the load current and the UPS limiter d-axis, i l_d is the load current of the motor d-axis, i l_q is the load current of the motor q-axis, Δi q is the difference between the load current of the motor q-axis and the UPS limiter. The over-storage command current is set as follows: wherein, is an over-stored d-axis command current, is an over-stored q-axis command current; Real-time adjustment of the over-storage output current gain is expressed as: G sc = f(SOC sc ) where SOC sc is the state of charge of the supercapacitor, G sc is a gain factor calculated as a function of SOC sc The super- storage output command current is expressed as: When the superstore system is quickly activated to provide current.

6. The hybrid energy storage based multi-motor black start power coordination method according to claim 5, wherein, The black start process of motor 2 includes: Confirming that the motor 1 is running stably, the system has the capacity to start the motor 2, detecting i abc The total current, the motor 2 is identified, the incremental load current is calculated, which is represented as: Δi abc = i abc (t)-i abc (t-Δt) Wherein, Δt is the sampling time interval, Δi abc is the total current difference value after Δt time, t is the time variable, the incremental current characteristic parameter is analyzed, the incremental characteristic is compared with the motor 2 characteristic library, the accurate identification of the motor 2 under the operation of the motor 1 is represented as: wherein F Δi is the current incremental feature parameter, F i2 is the motor 2 feature library parameter, ε2 is the second recognition threshold, and S2 is the similarity evaluation index of the motor 2. The uninterruptible power supply current limit is readjusted dynamically. The total rated d-axis current and total rated q-axis current required for the joint operation of motor 1 and motor 2 are calculated and expressed as follows: wherein, Id_total represents the total rated d-axis current required for the combined operation of motor 1 and motor 2, Id2 represents the rated d-axis current for motor 2, and k2 is a safety factor for motor 2, n2 Id2 represents the rated d-axis current for motor 2, and k2 is a safety factor for motor 2, φ2 is the power factor angle for motor 2, Iq_total represents the total rated q-axis current required for the combined operation of motor 1 and motor 2, Iq2 represents the rated q-axis current for motor 2.

7. The multi-motor black-start power coordination method based on hybrid energy storage as described in claim 6, characterized in that, The black start process for motor 2 also includes: The uninterruptible power supply current limit is dynamically adjusted to a new value, expressed as: in, This represents the adjusted d-axis uninterruptible power supply current limit. This is represented as the adjusted q-axis uninterruptible power supply current limit; The secondary auxiliary start-up control of the over-storage system is performed, and the difference between the total load current and the limit of the new uninterruptible power supply is calculated in real time, expressed as: The new over-storage command current is set as follows: Considering the current SOC state of the supercapacitor, the output gain is adjusted as follows: G sc = f(SOC sc ) The final over-storage output command current is: When the starting current At that time, the over-storage system quickly restarted, providing the differential current; Implement a second smooth transition control and monitor the trend of total load current changes. and When the total load current Furthermore, once the operation is stable, motor 2 completes its startup and smoothly exits, with the over-storage command current smoothly decreasing to zero again. when When the over-storage system completely shuts down and enters standby mode or disconnects the switch, the uninterruptible power supply system completely takes over the load of the two motors. Multi-motor stable operation monitoring is carried out, a multi-motor stable operation characteristic parameter library is established, and the system operation status is monitored in real time.

8. A multi-motor black-start power coordination system based on hybrid energy storage, using the method described in any one of claims 1-7, characterized in that, include: Initialization module, initializes a multi-motor black start system based on supercapacitor energy storage and uninterruptible power supply; The motor 1 starting module initializes the system, performs a black start process for motor 1, and monitors stable operation. The motor 2 starting module performs a black start process for motor 2 when motor 1 is running stably.

9. An electronic device, comprising: Memory and processor; The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions. When the computer-executable instructions are executed by the processor, they implement the steps of the multi-motor black-start power coordination method based on hybrid energy storage as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing computer-executable instructions that, when executed by a processor, implement the steps of the multi-motor black-start power coordination method based on hybrid energy storage as described in any one of claims 1 to 7.

Images