Super capacitor connection method and system suitable for high-voltage IGBT bus

Abstract

The invention discloses a super capacitor connection method and system suitable for a high-voltage IGBT bus, and the method comprises the steps: monitoring the change of the voltage of the high-voltage IGBT bus in real time, automatically adjusting the voltage at the two ends of a super capacitor, carrying out the charging and discharging control of the super capacitor according to a charging and discharging control strategy, and connecting a protection module in a super capacitor circuit. The parameter optimization module optimizes the adjustment range of the voltage adjustment module and the control threshold value of the charging and discharging control strategy, the voltage of the high-voltage IGBT bus is accurately monitored, the voltage of the super capacitor is dynamically adjusted, the peak voltage can be quickly responded and efficiently absorbed, and the charging and discharging control and protection module is used for multiple protection mechanisms of the charging and discharging control and protection module. The super capacitor is prevented from being overcharged and overdischarged, the service life is prolonged, the system safety is enhanced, the super capacitor and the high-voltage IGBT bus are optimally matched by continuously optimizing system parameters, and the overall stability and the operation efficiency of the system are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of power electronics, and particularly relates to a supercapacitor connection method and system applicable to a high-voltage IGBT busbar. Background Art

[0002] In a power electronics system, IGBTs are often used as the main switching devices. When an IGBT turns off, due to the presence of stray inductance in the main circuit, the collector-emitter current will rapidly decrease. However, due to the inductance characteristics, the current cannot change instantaneously, which will generate an induced electromotive force and form a spike voltage. If the spike voltage is too high, it may damage the IGBT. To suppress the spike voltage and protect the IGBT, measures need to be taken at both ends of the DC busbar. Connecting a supercapacitor to the high-voltage IGBT busbar can absorb the spike voltage and play a protective role. Currently, the connection method of supercapacitors is usually to directly connect the supercapacitors in parallel at both ends of the high-voltage IGBT busbar, enabling the supercapacitors to quickly respond to the spike voltage. For example, the patent document with the application number CN202223048407.0 discloses a new type of electrolytic capacitor type power unit module. The DC capacitor is installed below the unit main housing and is connected to the IGBT and the three-phase rectifier bridge through the DC busbar, minimizing the distance between the positive and negative busbars of the DC busbar. An insulating plate is used to isolate the positive and negative of the IGBT connection row to meet the insulation requirements between the positive and negative rows and reduce the stray inductance of the busbar. An insulating plate is installed at the connection between the rectifier bridge connection row and the incoming cable end to ensure the electrical clearance requirements between the input cable and the connection row. The output copper row is fixed to the unit main housing with insulators to ensure that the output copper row does not deform when stressed. This utility model reduces the installation process while meeting the electrical performance of the power unit, and has the characteristics of small size, low cost, high assembly and maintenance efficiency, etc.

[0003] However, since the voltage level and capacity of the supercapacitor need to be strictly matched with the busbar, otherwise the spike voltage cannot be effectively absorbed. Moreover, when the busbar voltage fluctuates greatly, it may cause overcharging or over-discharging of the supercapacitor, affecting its life and performance. Therefore, we need to propose a supercapacitor connection method and system applicable to a high-voltage IGBT busbar to solve the above existing problems, enabling overvoltage protection and undervoltage protection of the supercapacitor, and continuously optimizing the system parameters to achieve the best match between the supercapacitor and the high-voltage IGBT busbar, improving the overall stability and operation efficiency of the system, and thus increasing the service life of the supercapacitor. Summary of the Invention

[0004] The purpose of the present invention is to provide a method and system for connecting a supercapacitor suitable for a high-voltage IGBT bus, which can perform overvoltage protection and undervoltage protection on the supercapacitor, and continuously optimize system parameters to achieve the best matching between the supercapacitor and the high-voltage IGBT bus, improve the overall stability and operation efficiency of the system, and extend the service life of the supercapacitor, so as to solve the problems proposed in the above background technology.

[0005] To achieve the above object, the present invention adopts the following technical solutions: A method for connecting a supercapacitor suitable for a high-voltage IGBT bus, comprising the following steps: S1. Install a voltage detection module at the high-voltage IGBT bus to monitor the change of the high-voltage IGBT bus voltage in real time; S2. Connect a voltage regulation module between the supercapacitor and the high-voltage IGBT bus, and automatically adjust the voltage across the supercapacitor according to the difference between the detected high-voltage IGBT bus voltage and the supercapacitor voltage; S3. Develop a charge-discharge control strategy for the supercapacitor according to the voltage fluctuation of the high-voltage IGBT bus through a charge-discharge control module, and perform charge-discharge control on the supercapacitor according to the charge-discharge control strategy; S4. Connect a protection module in the supercapacitor circuit to cut off the circuit in time when an abnormal situation occurs and protect the safety of the supercapacitor; S5. Optimize the adjustment range of the voltage regulation module and the control threshold of the charge-discharge control strategy through a parameter optimization module according to the actual high-voltage IGBT bus voltage range and the characteristics of the supercapacitor.

[0006] Preferably, the voltage detection module includes a voltage sensor, a signal conditioning circuit, an A / D converter, and a data transmission interface. The voltage sensor is directly connected to the high-voltage IGBT bus. The signal conditioning circuit amplifies and filters the output signal of the voltage sensor to remove noise interference. The A / D converter converts the analog signal into a digital signal, and the data transmission interface transmits the digital signal to the voltage regulation module.

[0007] Preferably, the voltage regulation module includes a DC-DC converter, a control chip, and a feedback circuit. The control chip is respectively connected to the voltage detection module, the DC-DC converter, and the feedback circuit. The feedback circuit collects the supercapacitor voltage and feeds it back to the control chip. The control chip receives the voltage data collected by the feedback circuit and the voltage data monitored by the voltage detection module, calculates their difference, and generates an output control signal using a PID control algorithm. The DC-DC converter adjusts the voltage of the supercapacitor according to the control signal.

[0008] Preferably, the charge and discharge control strategy includes threshold setting, voltage judgment, charge and discharge rules, and charge and discharge rate control. Among them, threshold setting is to preset the overcharge threshold, over-discharge threshold, and buffer interval threshold of the high-voltage IGBT bus. The overcharge threshold is used to judge whether the bus voltage is too high, the over-discharge threshold is used to judge whether the bus voltage is too low, and the buffer interval threshold is used to prevent the supercapacitor from frequently charging and discharging when the bus voltage fluctuates near the threshold; There are the following three situations for voltage judgment and charge and discharge rules: When the voltage of the high-voltage IGBT bus is greater than the overcharge threshold, control the supercapacitor to discharge and release electrical energy to reduce the bus voltage; When the voltage of the high-voltage IGBT bus is less than or equal to the over-discharge threshold, control the supercapacitor to charge and absorb electrical energy to increase the bus voltage; When the voltage of the high-voltage IGBT bus is between the sum of the over-discharge threshold and the buffer interval threshold and the difference between the overcharge threshold and the buffer interval threshold, keep the current state of the supercapacitor and do not perform charge and discharge operations; Charge and discharge rate control is to dynamically adjust the magnitude of the charge and discharge current of the supercapacitor according to the degree of deviation of the high-voltage IGBT bus voltage from the threshold.

[0009] Preferably, the charge and discharge control module includes a microcontroller, a logic circuit, and a drive circuit. The microcontroller is respectively connected to the voltage detection module and the logic circuit. The drive circuit is respectively connected to the drive circuit and the supercapacitor. The microcontroller performs logical judgment, the logic circuit is used to process control signals, and the drive circuit controls the supercapacitor to charge and discharge.

[0010] Preferably, the charge and discharge control module executes the following charge and discharge control process for the supercapacitor: A1. The microcontroller obtains the real-time voltage data of the high-voltage IGBT bus from the voltage detection module and compares the real-time voltage data with the overcharge threshold, over-discharge threshold, and buffer interval threshold; A2. The microcontroller generates a control signal according to the comparison result. There are the following three situations for generating the control signal: When the voltage of the high-voltage IGBT bus is greater than the overcharge threshold, the microcontroller generates a discharge control instruction; When the voltage of the high-voltage IGBT bus is less than or equal to the over-discharge threshold, the microcontroller generates a charge control instruction; When the voltage of the high-voltage IGBT bus is between the sum of the over-discharge threshold and the buffer interval threshold and the difference between the overcharge threshold and the buffer interval threshold, the microcontroller generates a hold control instruction; A3. The logic circuit receives the control instruction sent by the microcontroller, converts the control instruction into a control signal suitable for the drive circuit, and transmits the control signal to the drive circuit; A4. The drive circuit controls the charging and discharging operations of the supercapacitor according to the received control signal; A5. Repeat steps A1 - A4 to continuously monitor the high - voltage IGBT bus voltage and perform charge - discharge control.

[0011] Preferably, the protection module includes an over - voltage protection circuit, an under - voltage protection circuit, an over - current protection circuit, a short - circuit protection circuit, and a switching device. The switching device is connected in series between the supercapacitor and the high - voltage IGBT bus. The over - voltage protection circuit, under - voltage protection circuit, over - current protection circuit, and short - circuit protection circuit are all connected to the circuit of the supercapacitor, and the control terminals of the over - voltage protection circuit, under - voltage protection circuit, over - current protection circuit, and short - circuit protection circuit are all connected to the switching device.

[0012] Preferably, the parameter optimization module includes a data collection and pre - processing unit, an optimization objective function determination unit, a parameter adjustment and optimization unit, and a parameter verification unit connected in sequence. The data collection and pre - processing unit collects and processes data on the high - voltage IGBT bus voltage range and supercapacitor characteristics. The optimization objective function determination unit constructs an optimization objective function based on the collected data. The parameter adjustment and optimization unit adjusts and optimizes the adjustment range of the voltage regulation module and the control threshold of the charge - discharge control strategy. The parameter verification unit conducts simulation tests on the adjusted parameters and applies the parameters that meet the test requirements to the actual system.

[0013] Preferably, the parameter adjustment and optimization unit performs the following adjustment and optimization steps: C1. Establish a parameter population based on the adjustment range parameters of the voltage regulation module and the control threshold of the charge - discharge control strategy; C2. Perform an initialization operation on the parameter population. Each individual represents a set of parameter values, and calculate the fitness function value of each individual. The calculation formula of the fitness function value is: , where is the probability that the individual is selected, is the fitness function value of the individual , is the number of individuals in the population, is the th individual in the population; C3. Select one individual, pair the selected individuals in pairs for crossover to generate new individuals; C4. Select other individuals in sequence and pair the selected individuals in pairs for crossover until all individuals are selected; C5. Calculate the fitness function value of each new individual, and select the parameter value corresponding to the individual with the optimal fitness function value as the optimized parameter.

[0014] Based on the supercapacitor connection method for high-voltage IGBT busbars described above, the present invention also provides a supercapacitor connection system for high-voltage IGBT busbars, including: a voltage detection module installed at the high-voltage IGBT busbar to continuously monitor the busbar voltage in real time; a voltage regulation module that receives the busbar voltage data and the voltage data of the supercapacitor transmitted by the voltage detection module and calculates, and dynamically adjusts the voltage across the supercapacitor according to the calculation result; a charge and discharge control module that formulates a charge and discharge control strategy for the supercapacitor and performs charge and discharge control according to the voltage fluctuation of the high-voltage IGBT busbar through the charge and discharge control module; a protection module that continuously monitors the voltage and current conditions in the supercapacitor circuit, and once an abnormal condition is detected, the protection circuit will act quickly; a parameter optimization module that comprehensively analyzes the actual voltage range of the high-voltage IGBT busbar, the capacitance of the supercapacitor, and the characteristic parameters of the withstand voltage value, and automatically optimizes and adjusts the key parameters such as the adjustment range of the voltage regulation module and the threshold value of the charge and discharge control module according to the analysis result.

[0015] A supercapacitor connection method and system for high-voltage IGBT busbars proposed by the present invention have the following advantages compared with the prior art: 1. By accurately monitoring the voltage of the high-voltage IGBT busbar and dynamically adjusting the voltage of the supercapacitor, the present invention can quickly respond and efficiently absorb the peak voltage. Through the multiple protection mechanisms of the charge and discharge control and protection modules, overcharging and over-discharging of the supercapacitor are avoided, the service life is extended, the system safety is enhanced, and through continuous optimization of the system parameters, the supercapacitor and the high-voltage IGBT busbar reach the best match, improving the overall stability and operation efficiency of the system.

[0016] 2. Through the coordinated cooperation of the voltage detection module, voltage regulation module, charge and discharge control module, protection module, and parameter optimization module, the present invention realizes the efficient connection and stable operation of the high-voltage IGBT busbar and the supercapacitor, enabling the system to quickly respond to the peak voltage fluctuations of the busbar voltage, effectively absorb the peak voltage, avoid overcharging and over-discharging of the supercapacitor, and extend its service life; at the same time, the optimized system parameters enable the supercapacitor to reach the best adaptation state with the busbar, significantly improving the overall stability, reliability, and operation efficiency of the system, providing a strong guarantee for the stable operation of the high-voltage IGBT busbar system. Description of the Drawings

[0017] Figure 1Shows a flowchart of the connection method according to an embodiment of the present invention; Figure 2 Shows a flowchart of the charge and discharge control module for controlling the charge and discharge of a supercapacitor according to an embodiment of the present invention; Figure 3 Shows a flowchart of the adjustment and optimization process by the parameter adjustment and optimization unit according to an embodiment of the present invention; Figure 4 Shows a system block diagram of the connection system according to an embodiment of the present invention. Detailed implementation manners

[0018] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0019] The present invention provides a Figures 1 - 3 supercapacitor connection method applicable to a high-voltage IGBT bus as shown below, including the following steps: S1. Install a voltage detection module at the high-voltage IGBT bus to monitor the change of the high-voltage IGBT bus voltage in real time; through the voltage detection module, the bus voltage information can be quickly and accurately obtained, providing a reliable data basis for subsequent control strategies. By real-time monitoring of the bus voltage, the fluctuation of the bus voltage can be found in time, providing a basis for the charge and discharge control of the supercapacitor; The voltage detection module includes a voltage sensor, a signal conditioning circuit, an A / D converter, and a data transmission interface. The voltage sensor is directly connected to the high-voltage IGBT bus. The signal conditioning circuit amplifies and filters the output signal of the voltage sensor to remove noise interference; the A / D converter converts the analog signal into a digital signal, and the data transmission interface transmits the digital signal to the voltage regulation module; The calculation formula for the amplification operation of the signal conditioning circuit is: , where is the amplified voltage value, is the input voltage value, is the amplification factor; The calculation formula for the filtering operation of the signal conditioning circuit is: , where is the filtered voltage value, is the complex frequency, is the amplified voltage value, R is the resistance value, and C is the capacitance value; S2. Connect a voltage regulation module between the supercapacitor and the high-voltage IGBT bus. According to the difference between the detected high-voltage IGBT bus voltage and the supercapacitor voltage, automatically regulate the voltage across the supercapacitor; through the regulation of the voltage regulation module, the voltage of the supercapacitor can be matched with the high-voltage IGBT bus voltage, thereby effectively absorbing the spike voltage, improving the response ability of the supercapacitor to the spike voltage, and enhancing the absorption effect of the supercapacitor; The voltage regulation module includes a DC-DC converter, a control chip, and a feedback circuit. The control chip is respectively connected to the voltage detection module, the DC-DC converter, and the feedback circuit. The feedback circuit collects the supercapacitor voltage and feeds it back to the control chip. The control chip receives the voltage data collected by the feedback circuit and the voltage data monitored by the voltage detection module, calculates their difference, and generates an output control signal using the PID control algorithm. The DC-DC converter regulates the voltage of the supercapacitor according to the control signal.

[0020] The PID control algorithm formula is: , where is the control signal, is the voltage difference between the voltage data collected by the feedback circuit and the voltage data monitored by the voltage detection module at time is the proportionality coefficient, is the integral coefficient, is the differential coefficient; is the integral variable of the small change, which is for in the interval from 0 to t, based on of the small change for cumulative summation; represents the small change in the voltage difference , is the small change in time t; S3. Develop a charge and discharge control strategy for the supercapacitor according to the voltage fluctuation of the high-voltage IGBT bus through the charge and discharge control module, and control the charge and discharge of the supercapacitor according to the charge and discharge control strategy; the charge and discharge control strategy is used to control the supercapacitor to discharge when the high-voltage IGBT bus voltage rises and to charge the supercapacitor when the high-voltage IGBT bus voltage drops; through the formulation of the charge and discharge control strategy, reasonable charge and discharge control of the supercapacitor can be carried out, enabling the supercapacitor to work stably when the high-voltage IGBT bus fluctuates, and improving the stability and reliability of the entire system; The charge and discharge control strategy includes threshold setting, voltage judgment and charge and discharge rules, and charge and discharge rate control. Among them, threshold setting is to preset the overcharge threshold, over-discharge threshold and buffer interval threshold of the high-voltage IGBT bus. The overcharge threshold is used to judge whether the bus voltage is too high, the over-discharge threshold is used to judge whether the bus voltage is too low, and the buffer interval threshold is used to avoid frequent charge and discharge of the supercapacitor when the bus voltage fluctuates near the threshold, reducing the loss of supercapacitor components; There are the following three situations for voltage judgment and charge and discharge rules: When the voltage of the high-voltage IGBT bus is greater than the overcharge threshold, control the supercapacitor to discharge and release electrical energy to reduce the bus voltage; When the voltage of the high-voltage IGBT bus is less than or equal to the over-discharge threshold, control the supercapacitor to charge and absorb electrical energy to increase the bus voltage; When the voltage of the high-voltage IGBT bus is between the sum of the over-discharge threshold and the buffer interval threshold and the difference between the overcharge threshold and the buffer interval threshold, keep the current state of the supercapacitor and do not perform charge and discharge operations.

[0021] Charge and discharge rate control is to dynamically adjust the magnitude of the charge and discharge current of the supercapacitor, that is, the charge and discharge rate, according to the degree of deviation of the high-voltage IGBT bus voltage from the threshold. The greater the degree of deviation, the greater the charge and discharge current to adjust the bus voltage more quickly; the smaller the degree of deviation, the smaller the charge and discharge current to prevent over-adjustment.

[0022] The charge and discharge control module includes a microcontroller, a logic circuit and a drive circuit. The microcontroller is respectively connected to the voltage detection module and the logic circuit. The drive circuit is respectively connected to the drive circuit and the supercapacitor. Logical judgment is performed by the microcontroller. The logic circuit is used to process control signals, and the drive circuit controls the supercapacitor to charge and discharge.

[0023] The charge and discharge control module executes the following charge and discharge control process for the supercapacitor: A1. The microcontroller obtains the real-time voltage data of the high-voltage IGBT bus from the voltage detection module, and compares the real-time voltage data with the overcharge threshold, over-discharge threshold and buffer interval threshold; A2. The microcontroller generates control signals according to the comparison results. There are the following three situations for generating control signals: When the voltage of the high-voltage IGBT bus is greater than the overcharge threshold, the microcontroller generates a discharge control instruction; When the voltage of the high-voltage IGBT bus is less than or equal to the over-discharge threshold, the microcontroller generates a charge control instruction; When the voltage of the high-voltage IGBT bus is between the sum of the over-discharge threshold and the buffer interval threshold and the difference between the overcharge threshold and the buffer interval threshold, the microcontroller generates a hold control instruction; A3. The logic circuit receives the control instructions sent by the microcontroller, converts the control instructions into control signals suitable for the drive circuit, and transmits the control signals to the drive circuit; A4. The drive circuit controls the charging and discharging operations of the supercapacitor according to the received control signals. Specifically: If the control signal is a discharge signal, the supercapacitor is started to discharge, and the discharge current of the supercapacitor is adjusted. The discharge current adjustment formula is: , where is the discharge current, is the discharge rate coefficient, is the high-voltage IGBT bus voltage, is the overcharge threshold voltage; If the control signal is a charging signal, the supercapacitor is started to charge, and the charging current of the supercapacitor is adjusted. The charging current adjustment formula is: , where is the charging current, is the charging rate coefficient, is the high-voltage IGBT bus voltage, is the over-discharge threshold voltage; If the control signal is a hold signal, the charging and discharging circuit of the supercapacitor is turned off; A5. Repeat steps A1 - A4, continuously monitor the high-voltage IGBT bus voltage and perform charge and discharge control.

[0024] S4. Connect a protection module in the supercapacitor circuit. When an abnormal situation occurs, the circuit can be cut off in time to protect the safety of the supercapacitor. Through the setting of the protection module, the safety of the system can be further enhanced. Even when the control strategy fails or other unexpected situations occur, the protection module can act in time to prevent the supercapacitor from being damaged and improve the risk resistance ability of the system; The protection module includes an overvoltage protection circuit, an undervoltage protection circuit, an overcurrent protection circuit, a short-circuit protection circuit and a switching device. The switching device is connected in series between the supercapacitor and the high-voltage IGBT bus. The overvoltage protection circuit, undervoltage protection circuit, overcurrent protection circuit and short-circuit protection circuit are all connected to the circuit of the supercapacitor, and the control terminals of the overvoltage protection circuit, undervoltage protection circuit, overcurrent protection circuit and short-circuit protection circuit are all connected to the switching device. The supercapacitor is protected against overvoltage, undervoltage, overcurrent and short circuit through the overvoltage protection circuit, undervoltage protection circuit, overcurrent protection circuit and short-circuit protection circuit. When an abnormality occurs in the circuit, the switching device is triggered to cut off the circuit to protect the safety of the supercapacitor.

[0025] Among them, the overvoltage protection circuit mainly consists of a voltage sampling circuit, a voltage comparator, a trigger circuit, and a driver. The voltage sampling circuit is generally composed of a resistor voltage division network, which is connected across the supercapacitor and used to collect the terminal voltage of the supercapacitor; the voltage comparator is used to compare the sampled voltage with a preset overvoltage threshold; the trigger circuit is activated when the comparison result meets the overvoltage condition; and the driver is used to control the operation of the switching device. The undervoltage protection circuit also includes a voltage sampling circuit, a voltage comparator, a trigger circuit, and a driver. Its voltage sampling circuit is similar to that of the overvoltage protection circuit and also uses a resistor voltage division network to collect the voltage of the supercapacitor; the voltage comparator is used to compare with the undervoltage threshold; and the functions of the trigger circuit and the driver are the same as those of the corresponding circuits in the overvoltage protection circuit.

[0026] The overcurrent protection circuit mainly consists of a current sensor, a signal amplification circuit, a comparator, and a trigger and drive circuit. The current sensor is used to detect the current in the supercapacitor circuit; the signal amplification circuit amplifies the weak signal output by the current sensor; the comparator is used to compare with the overcurrent threshold; and the trigger and drive circuit is used to control the switching device.

[0027] The short-circuit protection circuit consists of a fast-response current transformer, a comparator, and a trigger and drive circuit. The current transformer is used to quickly detect the short-circuit current; the comparator is used to judge whether a short circuit occurs; and the trigger and drive circuit is used to control the operation of the switching device.

[0028] S5. According to the actual high-voltage IGBT bus voltage range and the characteristics of the supercapacitor, the parameter optimization module optimizes the adjustment range of the voltage regulation module and the control threshold of the charge and discharge control strategy, so that the supercapacitor and the high-voltage IGBT bus can be better matched, improving the overall performance of the system. By optimizing the parameters, the performance advantages of the supercapacitor can be fully exerted, improving its absorption efficiency of spike voltage and its adaptability to the voltage fluctuation of the high-voltage IGBT bus.

[0029] The parameter optimization module includes a data collection and preprocessing unit, an optimization objective function determination unit, a parameter adjustment and optimization unit, and a parameter verification unit that are connected in sequence. The data collection and preprocessing unit collects and processes data on the high-voltage IGBT bus voltage range and the characteristics of the supercapacitor. The optimization objective function determination unit constructs an optimization objective function based on the collected data. The parameter adjustment and optimization unit adjusts and optimizes the adjustment range of the voltage regulation module and the control threshold of the charge and discharge control strategy. The parameter verification unit conducts simulation tests on the adjusted parameters and applies the parameters that meet the test requirements to the actual system.

[0030] The data collection and preprocessing unit executes the following data collection process: B1. Obtain the real-time voltage data sequence of the high-voltage IGBT bus within a period of time from the voltage detection module. The real-time voltage data sequence covers the voltage values under normal operation, fluctuations, and the occurrence of voltage spikes. B2. Obtain the charge and discharge historical data of the supercapacitor from the charge and discharge control module. The charge and discharge historical data includes the charge and discharge times, the magnitudes of the charge and discharge currents, and the charge and discharge durations. B3. Collect the characteristic parameters of the supercapacitor. The characteristic parameters include the rated voltage, the maximum capacity, the charge and discharge cut-off voltages, and the normal operating voltage range of the high-voltage IGBT bus. B4. Perform outlier removal and missing value filling on the collected real-time voltage data sequence, charge and discharge historical data, and characteristic parameters, and then organize the processed data in a unified format. The formula expression of the optimization objective function constructed by the optimization objective function determination unit is: , , , , , Where, is the output result of the optimization objective function, is the spike voltage absorption efficiency of the supercapacitor, is the response speed index of the supercapacitor to the voltage fluctuations of the high-voltage IGBT bus, is the working risk index of the supercapacitor, , and are the weight coefficients of the spike voltage absorption efficiency, the response speed index, and the working risk index respectively, is the actual charge absorbed by the supercapacitor, is the total charge generated by the spike voltage, is the response time of the supercapacitor from detecting the bus voltage fluctuation to starting to effectively regulate the voltage, is the number of overcharge or over-discharge occurrences of the supercapacitor within a certain period of time, is the total number of operation times.

[0031] The parameter adjustment and optimization unit performs the following adjustment and optimization steps: C1. Establish a parameter population according to the adjustment range parameter of the voltage regulation module and the control threshold of the charge and discharge control strategy. The formula expression of the parameter population is: , where, is the upper limit value of the adjustment range parameter, is the lower limit value of the adjustment range parameter, is the overcharge threshold, is the overdischarge threshold, is the buffer interval threshold; C2. Initialize the parameter population. Each individual represents a set of parameter values, and calculate the fitness function value of each individual. The calculation formula of the fitness function value is: , where is the probability that the individual is selected, is the fitness function value of the individual , is the number of individuals in the population, is the fitness function value of the th individual in the population; C3. Select one individual, pair the selected individuals in pairs to generate new individuals; The pairing process is as follows: Suppose the original individuals are: and , and the new individuals after pairing are: and , where n is the number of parameters in the individual, is the position of the crossover point, and are the two individuals before crossover respectively, and are and the two new individuals after crossover pairing respectively; C4. Select other individuals in turn and pair the selected individuals in pairs until all individuals are selected; C5. Calculate the fitness function value of each new individual, and select the parameter value corresponding to the individual with the optimal fitness function value as the optimized parameter; The process of the parameter verification unit for simulation testing is as follows: D1. Apply the optimized voltage regulation module adjustment range parameter and the charge and discharge control strategy control threshold to the system simulation model for simulation operation testing; D2. Observe the operation of the system under different working conditions, and verify whether the optimized parameters meet the set optimization goals, such as whether the supercapacitor can effectively absorb the peak voltage and whether overcharge and overdischarge are avoided; D3. If the simulation test result is not ideal, adjust the parameters of the optimization algorithm or reset the optimization goal, and repeat the optimization steps of the parameter adjustment and optimization unit; if the result meets the requirements, apply the optimized parameters to the actual system; By precisely monitoring the high-voltage IGBT bus voltage and dynamically adjusting the supercapacitor voltage, it can quickly respond and efficiently absorb the spike voltage. Through the multiple protection mechanisms of the charge and discharge control and protection module, overcharging and over-discharging of the supercapacitor can be avoided, its service life can be extended, the system security can be enhanced, and by continuously optimizing the system parameters, the supercapacitor and the high-voltage IGBT bus can achieve the best matching, improving the overall stability and operating efficiency of the system.

[0032] Based on the supercapacitor connection method applicable to the high-voltage IGBT bus described above, the present invention also provides a supercapacitor connection system applicable to the high-voltage IGBT bus, as Figure 4 shown, including a voltage detection module, a voltage regulation module, a charge and discharge control module, a protection module, and a parameter optimization module; the voltage detection module is installed at the high-voltage IGBT bus to continuously monitor the bus voltage in real time; The voltage regulation module receives the bus voltage data and the voltage data of the supercapacitor transmitted by the voltage detection module and calculates, and dynamically adjusts the voltage across the supercapacitor according to the calculation result, which can effectively solve the problem of mismatching of the voltage levels between the supercapacitor and the high-voltage IGBT bus, enabling the supercapacitor to quickly respond and absorb the spike voltage under different bus voltage conditions, improving the absorption efficiency and response speed of the spike voltage; The charge and discharge control module formulates the charge and discharge control strategy of the supercapacitor through the charge and discharge control module according to the voltage fluctuation of the high-voltage IGBT bus and conducts charge and discharge control to ensure that the supercapacitor always remains within a safe operating voltage range during the bus voltage fluctuation process, avoiding overcharging and over-discharging phenomena, thereby extending the service life of the supercapacitor and maintaining its stable performance; The protection module continuously monitors the voltage and current conditions in the supercapacitor circuit. Once it detects that the voltage exceeds the overvoltage threshold, is lower than the undervoltage threshold, or the current exceeds the rated value or a short circuit occurs, the protection circuit will quickly act to trigger the switching device to cut off the circuit and isolate the supercapacitor from the high-voltage IGBT bus. Even when the charge and discharge control module fails or other abnormal conditions occur, the protection module can intervene in time to protect the safety of the supercapacitor, the voltage regulation module, and other devices, greatly enhancing the security and reliability of the system.

[0033] The parameter optimization module comprehensively analyzes the actual voltage range of the high-voltage IGBT bus, the capacity of the supercapacitor, and the characteristic parameters of the withstand voltage value, and automatically optimizes and adjusts the key parameters such as the adjustment range of the voltage regulation module and the threshold of the charge and discharge control module according to the analysis results; through continuous parameter optimization, the supercapacitor and the high-voltage IGBT bus reach the best matching state, giving full play to the performance advantages of the supercapacitor and improving the adaptability of the system to different working conditions and the overall operating efficiency.

[0034] Through the coordinated cooperation of the voltage detection module, voltage regulation module, charge and discharge control module, protection module and parameter optimization module, the efficient connection and stable operation of the high-voltage IGBT bus and the supercapacitor are realized. Among them, the voltage detection module provides a data basis, the voltage regulation module solves the voltage matching problem, the charge and discharge control module ensures the safe operation of the supercapacitor, the protection module strengthens the system security defense line, and the parameter optimization module improves the system performance, enabling the system to quickly respond to the peak voltage fluctuations of the bus, effectively absorb the peak voltage, avoid overcharging and over-discharging of the supercapacitor, and extend its service life. At the same time, the optimized system parameters enable the supercapacitor and the bus to reach the best adaptation state, significantly improving the overall stability, reliability and operation efficiency of the system, providing a strong guarantee for the stable operation of the high-voltage IGBT bus system.

[0035] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A supercapacitor connection method applicable to a high-voltage IGBT bus, characterized in that: It includes the following steps: S1. Install a voltage detection module at the high-voltage IGBT bus to monitor the change of the high-voltage IGBT bus voltage in real time; S2. Connect a voltage regulation module between the supercapacitor and the high-voltage IGBT bus, and automatically adjust the voltage across the supercapacitor according to the difference between the detected high-voltage IGBT bus voltage and the supercapacitor voltage; S3. Develop a charge and discharge control strategy for the supercapacitor according to the high-voltage IGBT bus voltage fluctuation situation through the charge and discharge control module, and perform charge and discharge control on the supercapacitor according to the charge and discharge control strategy; S4. Connect a protection module in the supercapacitor circuit to be able to cut off the circuit in time when an abnormal situation occurs to protect the safety of the supercapacitor; S5. Optimize the adjustment range of the voltage regulation module and the control threshold of the charge and discharge control strategy through the parameter optimization module according to the actual high-voltage IGBT bus voltage range and the characteristics of the supercapacitor.

2. The supercapacitor connection method applicable to a high-voltage IGBT bus according to claim 1, wherein: The voltage detection module includes a voltage sensor, a signal conditioning circuit, an A / D converter and a data transmission interface. The voltage sensor is directly connected to the high-voltage IGBT bus. The signal conditioning circuit amplifies and filters the output signal of the voltage sensor to remove noise interference. The A / D converter converts the analog signal into a digital signal, and the data transmission interface transmits the digital signal to the voltage regulation module.

3. A supercapacitor connection method applicable to a high-voltage IGBT busbar according to claim 1, characterized in that: The voltage regulation module includes a DC-DC converter, a control chip and a feedback circuit. The control chip is respectively connected to the voltage detection module, the DC-DC converter and the feedback circuit. The feedback circuit collects the supercapacitor voltage and feeds it back to the control chip. The control chip receives the voltage data collected by the feedback circuit and the voltage data monitored by the voltage detection module to calculate their difference, and generates an output control signal using the PID control algorithm according to the difference. The DC-DC converter adjusts the voltage of the supercapacitor according to the control signal.

4. A supercapacitor connection method applicable to a high-voltage IGBT bus according to claim 1, characterized in that: The charge and discharge control strategy includes threshold setting, voltage judgment and charge and discharge rules, and charge and discharge rate control. Among them, threshold setting is to preset the overcharge threshold, over-discharge threshold and buffer interval threshold of the high-voltage IGBT bus. The overcharge threshold is used to judge whether the bus voltage is too high, the over-discharge threshold is used to judge whether the bus voltage is too low, and the buffer interval threshold is used to avoid frequent charge and discharge of the supercapacitor when the bus voltage fluctuates near the threshold; There are the following three situations for voltage judgment and charge and discharge rules: When the high-voltage IGBT bus voltage is greater than the overcharge threshold, control the supercapacitor to discharge and release electric energy to reduce the bus voltage; When the high-voltage IGBT bus voltage is less than or equal to the over-discharge threshold, control the supercapacitor to charge and absorb electric energy to increase the bus voltage; When the high-voltage IGBT bus voltage is between the sum of the over-discharge threshold and the buffer interval threshold and the difference between the overcharge threshold and the buffer interval threshold, keep the current state of the supercapacitor and do not perform charge and discharge operations; Charge and discharge rate control is to dynamically adjust the magnitude of the charge and discharge current of the supercapacitor according to the degree of deviation of the high-voltage IGBT bus voltage from the threshold.

5. A supercapacitor connection method applicable to a high-voltage IGBT bus according to claim 4, characterized in that: The charge and discharge control module includes a microcontroller, a logic circuit, and a drive circuit. The microcontroller is respectively connected to the voltage detection module and the logic circuit, and the drive circuit is respectively connected to the drive circuit and the supercapacitor. Logical judgment is performed by the microcontroller, the logic circuit is used to process control signals, and the drive circuit controls the charging and discharging of the supercapacitor.

6. The supercapacitor connection method applicable to a high-voltage IGBT bus according to claim 5, characterized in that: The charge and discharge control module performs the following charge and discharge control process on the supercapacitor: A1. The microcontroller obtains the real-time voltage data of the high-voltage IGBT bus from the voltage detection module, and compares the real-time voltage data with the overcharge threshold, the over-discharge threshold, and the buffer interval threshold; A2. The microcontroller generates control signals according to the comparison results. There are the following three situations in the generation of control signals: When the voltage of the high-voltage IGBT bus is greater than the overcharge threshold, the microcontroller generates a discharge control instruction; When the voltage of the high-voltage IGBT bus is less than or equal to the over-discharge threshold, the microcontroller generates a charge control instruction; When the voltage of the high-voltage IGBT bus is between the sum of the over-discharge threshold and the buffer interval threshold and the difference between the overcharge threshold and the buffer interval threshold, the microcontroller generates a hold control instruction; A3. The logic circuit receives the control instruction sent by the microcontroller, converts the control instruction into a control signal suitable for the drive circuit, and transmits the control signal to the drive circuit; A4. The drive circuit controls the charging and discharging operation of the supercapacitor according to the received control signal; A5. Repeat steps A1 - A4 to continuously monitor the voltage of the high-voltage IGBT bus and perform charge and discharge control.

7. A supercapacitor connection method applicable to a high-voltage IGBT busbar according to claim 5, characterized in that: The protection module includes an overvoltage protection circuit, an undervoltage protection circuit, an overcurrent protection circuit, a short-circuit protection circuit, and a switching device. The switching device is connected in series between the supercapacitor and the high-voltage IGBT bus. The overvoltage protection circuit, the undervoltage protection circuit, the overcurrent protection circuit, and the short-circuit protection circuit are all connected to the circuit of the supercapacitor, and the control terminals of the overvoltage protection circuit, the undervoltage protection circuit, the overcurrent protection circuit, and the short-circuit protection circuit are all connected to the switching device.

8. A supercapacitor connection method applicable to a high-voltage IGBT busbar according to claim 1, characterized in that: The parameter optimization module includes a data collection and preprocessing unit, an optimization objective function determination unit, a parameter adjustment and optimization unit, and a parameter verification unit connected in sequence. The data collection and preprocessing unit collects and processes data on the voltage range of the high-voltage IGBT bus and the characteristics of the supercapacitor. The optimization objective function determination unit constructs an optimization objective function based on the collected data. The parameter adjustment and optimization unit adjusts and optimizes the adjustment range of the voltage regulation module and the control thresholds of the charge and discharge control strategy. The parameter verification unit performs simulation tests on the adjusted parameters and applies the parameters that meet the test requirements to the actual system.

9. A method for connecting supercapacitors applicable to a high-voltage IGBT busbar according to claim 8, characterized in that: The parameter adjustment and optimization unit performs the following adjustment and optimization steps: C1. Establish a parameter population according to the adjustment range parameters of the voltage regulation module and the control thresholds of the charge and discharge control strategy; C2. Perform an initialization operation on the parameter population. Each individual represents a set of parameter values, and calculate the fitness function value of each individual. The calculation formula of the fitness function value is: , where is the probability of an individual being selected, is the fitness function value of an individual , is the number of individuals in the population, is the th individual's fitness function value in the population; C3. Select one of the individuals, pair the selected individuals pairwise to generate new individuals; C4. Select other individuals in sequence and perform pairwise crossover pairing on the selected individuals until all individuals are selected; C5. Calculate the fitness function value of each new individual, and select the parameter value corresponding to the individual with the optimal fitness function value as the optimized parameter.

10. A supercapacitor connection system applicable to a high-voltage IGBT busbar, which implements a method for connecting a supercapacitor applicable to a high-voltage IGBT busbar according to any one of claims 1-9, characterized in that: Including: A voltage detection module, installed at the high-voltage IGBT bus, continuously monitors the bus voltage in real time; A voltage regulation module, which receives the bus voltage data and the voltage data of the supercapacitor transmitted by the voltage detection module and calculates, and dynamically adjusts the voltage across the supercapacitor according to the calculation result; A charge and discharge control module, formulates a charge and discharge control strategy for the supercapacitor through the charge and discharge control module according to the voltage fluctuation of the high-voltage IGBT bus, and performs charge and discharge control; A protection module, which monitors the voltage and current conditions in the supercapacitor circuit in real time. Once an abnormal condition is detected, the protection circuit will act quickly; A parameter optimization module, which comprehensively analyzes the actual voltage range of the high-voltage IGBT bus, the capacity of the supercapacitor, and the characteristic parameters of the withstand voltage value, and automatically optimizes and adjusts the key parameters such as the adjustment range of the voltage regulation module and the threshold of the charge and discharge control module according to the analysis result.

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