Bidirectional Boost circuit output end three-level average voltage system

Abstract

The invention discloses a bidirectional Boost circuit output end three-level voltage averaging system, relates to the technical field of circuit output, and is used for solving the problem of voltage unbalance of a high-voltage side capacitor caused by a load effect in an off-grid state. Comprising a sampling module and a control module which are in signal connection. The sampling module adopts a Hall effect sensor to collect the current of an energy storage inductor, and carries out safe and accurate conditioning on the voltage of each capacitor. The control module dynamically adjusts the duty ratio and reasonable dead time of the IGBT switch tube by means of a PID algorithm based on voltage, current and temperature data acquired by the high-speed ADC, so that voltage deviation is effectively compensated, and safety risks are prevented. According to the system, the advantages of a traditional Boost circuit working mode are reserved, meanwhile, the voltage-sharing efficiency and the overall safety of the system are remarkably improved, and the system has the advantages of being simple in structure, rapid in response, accurate in control and the like and is suitable for various power electronic application occasions.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit output, and more particularly to a three-electrode average voltage system at the output end of a bidirectional Boost circuit. Background Art

[0002] Intelligent control technology is primarily used to automate complex systems and processes, enabling efficient, reliable, and intelligent operation. It is widely used in various fields, including industrial production, transportation, and energy management. Its application in rail transit turnout snow-melting systems can improve snow-melting efficiency and reduce track risks.

[0003] The existing technology has the following deficiencies:

[0004] In the past, the intelligent snow-melting control system for rail transit switches would start the snow-melting system in advance when the train was about to enter the switch area, ensuring that there was less snow on the switch before the train arrived. After the train left, the snow-melting system would be delayed to ensure the continuous snow-melting effect. However, the temperature difference between the heating temperature of the switch generated by the train passing through the snow-melting system and the temperature of the train wheels and rails in snowy weather was not taken into account, resulting in track deformation when the train passed through the switch and an increased risk of failure.

[0005] In view of the above problems, the present invention proposes a solution. Summary of the Invention

[0006] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides a three-electrode average voltage system at the output end of a bidirectional Boost circuit to solve the problems raised in the above-mentioned background technology.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] In a preferred embodiment, it includes: a sampling module, a control module, and signal connections between the modules;

[0009] The sampling module is mainly used to accurately collect power data in the power circuit, including inductor current and low- and high-voltage side capacitor voltages;

[0010] The control module is mainly used to dynamically adjust the IGBT duty cycle and dead time based on real-time feedback of temperature and switching delay.

[0011] In a preferred embodiment, the sampling module is designed for the inductor average current I that requires non-contact, fast response and high-precision isolation. boost , using a Hall effect sensor, connect the sensor in series or surround the conductor where the inductor is located so that it can capture the average current flowing through the inductor; and design an RC low-pass filter at the output end of the sensor to filter out high-frequency noise;

[0012] For the low-voltage side capacitor voltage U that requires high accuracy and stability during measurement bat The sampling module combines the resistor voltage divider and filter to reduce the voltage to a safe range and then measures the low-voltage side capacitor voltage U bat Conduct collection;

[0013] First, design a high-precision, low-drift resistor divider network, calculate the divider ratio, and select precision resistors to ensure a stable divider ratio with minimal error. Then, design an RC low-pass filter at the divider output to eliminate high-frequency noise.

[0014] The high-voltage side capacitor voltage U is required to be measured under the premise of ensuring safe isolation. p 、U n ,The sampling module adopts a high-voltage resistant voltage divider network, supplemented by an isolation amplifier and filtering measures;

[0015] First, high-voltage-resistant, precision resistors are selected to form a voltage divider network. The voltage divider ratio is calculated. After voltage division, a high-voltage isolation amplifier is added to the signal line. Independent voltage divider and isolation circuits are designed for the two capacitor terminals on the high-voltage side. An RC low-pass filter is added to the output of the isolation amplifier.

[0016] After power data acquisition is completed, the sampling module connects the conditioned outputs of current, low-voltage capacitor voltage, and high-voltage side capacitor voltage to the multi-channel ADC inside the acquisition module, and designs overvoltage, overcurrent, and ESD protection circuits for each sampling path. Finally, the acquisition module converts the processed signals into digital data and outputs them to the control module through the standard interface SPI.

[0017] In a preferred embodiment, the control module presets an initial dead time value based on the switching delay of the IGBT device data and the safety margin determined experimentally, and writes the initial value into the dead time register of the PWM timer in the control module initialization code;

[0018] The control module uses a temperature sensor to collect current real-time temperature data through ADC, and performs feedback sampling on the switch signal to obtain actual switch delay data;

[0019] The control module establishes an ideal dead time model based on temperature and calculates the ideal dead time under current conditions according to the formula: Tideal = T0 + Kt × (T-Tref), where Tideal represents the target dead time calculated based on the current temperature and other environmental conditions, T0 represents the baseline dead time, Tref represents the reference temperature, T represents the current real-time temperature, and Kt represents the temperature coefficient, which indicates the amount by which the ideal dead time needs to increase for every 1°C increase in temperature.

[0020] The control module compares the actual measured switching delay Tmeas with the ideal value to obtain the error Error, which is based on the formula: Error = Tmeas - Tideal. When Error > 0, it means that the actual delay exceeds the ideal value, which will reduce switching efficiency. When Error < 0, it means that the actual delay is lower than the ideal value, which may pose a safety risk.

[0021] The control module uses the PID control algorithm to dynamically adjust the dead time according to the dead time deviation. First, the dead time deviation ΔTdead is calculated. The specific formula is based on:

[0022]

[0023] Among them, Kp represents the proportional coefficient; Ki represents the integral coefficient; Kd represents the differential coefficient;

[0024] The control module uses the current dead time Tdead,current and the dead time deviation ΔTdead to determine the new dead time according to the formula: Tdead,new = Tdead,current + ΔTdead, and updates it discretely at fixed time intervals Ts according to the formula:

[0025] Discrete integral:

[0026] Discrete differential:

[0027] And substitute these discretized values into the PID formula;

[0028] The control module calls the interface function of the corresponding PWM timer or directly accesses the register to write the Tdead,new value into the dead time register; it performs synchronous updates within the "safety window" of the PWM cycle. After the update, the control module verifies whether the new dead time has taken effect through feedback detection.

[0029] In a preferred embodiment, the control module calculates the deviation ΔU of the high-voltage side capacitor voltage through the DSP, specifically according to the formula: ΔU = Uc1-Uc2, and determines the basic adjustment of the IGBT duty cycle D1, D2 according to the voltage deviation ΔU and the direction of the inductor current IL; if ΔU>0, it means that the voltage of C1 is too high and C2 needs to be charged to make it close to C1; if ΔU<0, it means that the voltage of C2 is too high and C1 needs to be charged; and a proportional factor k is set to calculate the basic duty cycle adjustment, specifically according to the formula: ΔDbasic = k×ΔU, where ΔDbasic is the preliminary adjustment value when other factors are not considered, and its positive and negative signs match the sign of ΔU and the direction of IL;

[0030] The control module sets the dead time compensation coefficient Kdt according to the dead time deviation ΔTdead, and determines the duty cycle compensation amount caused by the dead time deviation according to the formula: ΔDdt = Kdt × ΔTdead, where ΔDdt represents the duty cycle compensation amount;

[0031] The control module uses an STM32 microcontroller with a high-speed ADC module and a TMP36 temperature sensor, and is equipped with a dedicated IGBT gate feedback circuit. The embedded software obtains the current values of key component parameters through real-time monitoring and compares them with the design nominal values to obtain the parameter deviation index ΔP. The parameter compensation coefficient Kcomp is then set to calculate the component parameter compensation amount. The specific formula is: ΔDcomp = Kcomp × ΔP, where ΔDcomp represents the component parameter compensation amount.

[0032] The control module adds the adjustments of each part to obtain the final duty cycle adjustment value ΔDtotal, according to the formula: ΔDtotal = ΔDbasic + ΔDdt + ΔDcomp. The duty cycles D1 and D2 of the IGBT switches are then sent to the corresponding IGBT drivers in the power circuit through the driver circuit.

[0033] The control module obtains the inductor current I through the sampling module boost Determine whether the circuit is in the charging state or the discharging state, and then control the on and off of the IGBT through the driving circuit according to the duty cycle D1, D2 calculated by DSP.

[0034] The present invention discloses a three-electrode voltage averaging system at the output end of a bidirectional Boost circuit, which relates to the field of circuit output technology and is used to solve the problem of voltage imbalance of the high-voltage side capacitor caused by the load in an off-grid state; it includes a sampling module, a control module, and signal connections between the modules; the sampling module uses a Hall effect sensor to collect the current of the energy storage inductor, and safely and accurately regulates the voltage of each capacitor. The control module dynamically adjusts the duty cycle and reasonable dead time of the IGBT switch tube based on the voltage, current and temperature data collected by the high-speed ADC with the help of the PID algorithm, thereby effectively compensating for voltage deviations and preventing the occurrence of safety risks. While retaining the advantages of the traditional Boost circuit working mode, the system significantly improves the voltage balancing efficiency and the overall safety of the system. It has the advantages of simple structure, rapid response, precise control, etc., and is suitable for various power electronics applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1A schematic diagram shows the power circuit's principle. The circuit's input voltage source is stabilized by a low-voltage capacitor connected in parallel, then connected in series with an energy storage inductor. One end of the inductor is connected to IGBT switches Q1 and Q2, and the other end is connected to Q3 and Q4, forming a bidirectional control path. The high-voltage capacitor is connected in parallel at the output, with the intermediate node controlled by Q3 and Q4, alternating with the inductor.

[0036] Figure 2 Indicates that when ( or ) circuit operating state, where the input voltage source enters the power circuit through the low-voltage side capacitor in parallel and the energy storage inductor in series. At this time, IGBT switches Q1 and Q2 are on, while Q3 and Q4 are off. Current flows from the input through the low-voltage side capacitor to the inductor. The high-voltage side capacitor does not participate in energy conversion, and current does not flow to the load.

[0037] Figure 3 when The circuit operates in this state, where the input voltage is stabilized by the low-voltage side capacitor in parallel and then enters the power circuit through the series energy storage inductor. At this point, IGBT switches Q1 and Q2 are off, Q3 is on, and Q4 remains off. The energy stored in the inductor is released, and current flows from Q3 to the high-voltage side capacitor.

[0038] Figure 4 Indicates that when ( or ), the circuit operates in this state, where the input voltage is stabilized by the low-voltage side capacitor in parallel and then connected to the series energy storage inductor to enter the power circuit. At this point, IGBT switches Q1 and Q2 are off, Q4 is on, and Q3 remains off. The energy stored in the inductor is released, and current flows from Q4 to the high-voltage side capacitor.

[0039] Figure 5 Indicates when The circuit operates in this state, where the input voltage is stabilized by the low-voltage side capacitor in parallel before entering the power circuit through the series energy storage inductor. At this point, IGBT switches Q3 and Q4 are alternately turned on, while Q1 and Q2 are turned off, allowing the inductor to charge and discharge the high-voltage side capacitor in turn.

[0040] Figure 6 Schematic diagram of the current-time relationship curve of the traditional Boost circuit.

[0041] Figure 7 Schematic diagram of the current-time relationship curve after the voltage equalization system is improved.

[0042] Figure 8 This is a schematic diagram of the structure of a three-electrode average voltage system at the output end of a bidirectional Boost circuit according to the present invention. DETAILED DESCRIPTION

[0043] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0044] Example

[0045] The invention discloses a three-electrode average voltage system at the output end of a bidirectional Boost circuit, comprising a sampling module, a control module, and signal connections between the modules.

[0046] The boost circuit has different voltage balancing requirements in different modes. When the voltage balancing system is in a grid-connected working state or other working state that does not require voltage balancing regulation, it can work like a traditional boost circuit.

[0047] When the voltage balancing system is in an off-grid working state or other working state requiring voltage balancing regulation, the load will cause the voltage of the high-voltage side capacitor to be unbalanced. The Boost circuit starts the voltage balancing function to effectively prevent bus voltage imbalance and improve system safety.

[0048] The sampling module includes a low-voltage side capacitor (C bat ), energy storage inductor (L1, L2), IGBT (Q1, Q2, Q3, Q4), high voltage side capacitor (C p 、C n ) power circuit to collect power data, including: average inductor current (I boost ), low-voltage side capacitor voltage (U bat ) and the high-voltage side capacitor voltage (U p 、U n );

[0049] Among them, Q1 and Q2 are a pair of complementary IGBT switches, which are controlled by the duty cycle signal D1; Q3 and Q4 are a pair of complementary IGBT switches, which are controlled by the duty cycle signal D2;

[0050] Specifically, during the power data collection process, dedicated solutions are used for different power data, and the optimal conditioning circuit is designed for each signal to make the collected data more accurate;

[0051] In order to reflect the current size in the energy storage inductor, the average inductor current (I boost), using a dedicated Hall-effect sensor such as the ACS758 or ACS712 that features non-contact measurement, good isolation, and sufficient response speed, suitable for current signal measurement. The sensor is connected in series with or surrounded by the conductor where the inductor is located to enable it to capture the average current flowing through the inductor. Next, an RC low-pass filter is designed at the sensor output to filter out high-frequency noise.

[0052] If the sensor output voltage range does not match the ADC, use a precision operational amplifier to adjust the signal amplitude and DC offset to ensure that the output signal is within the ideal ADC input range;

[0053] The capacitor voltage is generally low (about tens of volts), and the low-voltage side capacitor voltage (U bat ), which is susceptible to high-frequency interference or ADC input voltage limitation when measured directly. Therefore, in this embodiment, the voltage is reduced to a safe range by combining resistor voltage division and filtering, and then the low-voltage side capacitor voltage (U bat ) for collection.

[0054] First, design a high-precision, low-drift resistor divider network and calculate the voltage divider ratio. For example, if the maximum voltage is 50V and the ADC's safe input range is 0–5V, design a 10:1 voltage divider ratio. Use precision resistors to ensure a stable voltage divider ratio with minimal error. Then, design an RC low-pass filter at the divider output to eliminate high-frequency noise.

[0055] For high voltage (hundreds of volts or higher), it is required to measure the high voltage side capacitor voltage (U p 、U n ), direct acquisition has safety risks, and the divided signal is susceptible to high voltage interference. Therefore, in this embodiment, a high-voltage resistant voltage divider network is adopted, supplemented by an isolation amplifier and filtering measures to ensure that the acquisition process is both safe and accurate.

[0056] First, select high-voltage-resistant, precision resistors to form a voltage-divider network and calculate the voltage-divider ratio. For example, if the maximum voltage is 400V and the target signal is 4V, the voltage-divider ratio is designed to be 100:1. After voltage division, add a high-voltage isolation amplifier to the signal line to achieve electrical isolation from the high-voltage side and provide signal buffering to reduce interference. Next, for the two capacitor terminals on the high-voltage side (for example, Uc1 and Uc2), design independent voltage-divider and isolation circuits to prevent mutual interference, and add an RC low-pass filter at the output of the isolation amplifier.

[0057] After power data acquisition is completed, the sampling module connects the conditioned outputs of current, low-voltage capacitor voltage, and high-voltage side capacitor voltage to the multi-channel ADC inside the acquisition module. Overvoltage, overcurrent, and ESD protection circuits are designed for each sampling path to prevent sudden interference or electrostatic shock from damaging the ADC or conditioning circuit. Finally, the acquisition module converts the processed signal into digital data and outputs it to the control module through a standard interface (such as SPI, IC, etc.).

[0058] The control module sets a reasonable dead time between the complementary switch tubes (Q1, Q2 and Q3, Q4) to ensure that the complementary switches are not turned on at the same time to prevent short circuit.

[0059] First, the control module presets an initial dead-time value (e.g., 100 ns) based on device data (e.g., IGBT or MOSFET switching delay) and experimentally determined safety margins. This initial value is written into the PWM timer's dead-time register within the control module's initialization code to prevent switching overlap due to improper adjustment at power-up. This ensures that the complementary switches are in a safe operating range upon startup of the voltage-sharing system.

[0060] Furthermore, the control module uses a temperature sensor to collect current real-time temperature data through an ADC, and performs feedback sampling on the switch signal to obtain actual switch delay data;

[0061] Furthermore, to determine whether the dead time needs to be adjusted, the control module establishes an ideal dead time model based on the temperature and calculates the ideal dead time under the current conditions according to the formula: Tideal = T0 + Kt × (T-Tref), where Tideal represents the target dead time calculated based on the current temperature and other environmental conditions, T0 represents the baseline dead time, Tref represents the reference temperature, T represents the current real-time temperature, and Kt represents the temperature coefficient, which represents the amount by which the ideal dead time needs to increase for every 1°C increase in temperature.

[0062] Furthermore, after the ideal value is determined, the control module compares the actual measured switching delay Tmeas with the ideal value to obtain the error Error, specifically according to the formula: Error = Tmeas - Tideal. When Error>0, it means that the actual delay exceeds the ideal value (the dead time is set too long), which will reduce the switching efficiency; when Error<0, it means that the actual delay is lower than the ideal value, which will pose a safety risk.

[0063] Furthermore, the control module adopts the PID control algorithm to dynamically adjust the dead time according to the dead time deviation, so that the actual value gradually approaches the ideal value. First, the dead time deviation ΔTdead is calculated. The specific formula is based on:

[0064]

[0065] Among them, Kp represents the proportional coefficient; Ki represents the integral coefficient; Kd represents the differential coefficient. It should be noted that these parameters need to be determined by experimental debugging or simulation to obtain appropriate values.

[0066] Furthermore, the control module determines the new dead time by using the current dead time Tdead,current and the dead time deviation ΔTdead. Specifically, it is based on the formula: Tdead,new = Tdead,current + ΔTdead, and is discretely updated at a fixed time interval Ts (sampling period). Specifically, it is based on the formula:

[0067] Discrete integration:

[0068] Discrete differentiation:

[0069] Substitute these discretized values into the PID formula to achieve real-time adjustment.

[0070] Furthermore, after calculating the new dead time, the control module calls the interface function of the corresponding PWM timer or directly accesses the register, and writes the value of Tdead,new into the dead time register. Synchronous update is performed within the "safe window" of the PWM period. After the update, the control module verifies whether the new dead time has taken effect through feedback detection (such as measuring the output waveform and monitoring the switch state), and ensures that no short-circuit phenomenon occurs.

[0071] The control module processes and stores the power data obtained from the sampling part, calculates the deviation ΔU of the high-voltage side capacitor voltage through DSP. Specifically, it is based on the formula: ΔU = Uc1 - Uc2, and determines the basic adjustment amounts of the duty cycles D1 and D2 of the IGBT according to the direction of the voltage deviation ΔU and the inductor current IL.

[0072] Specifically, if Uc1 > Uc2, it means that the voltage of C1 is too high, and C2 needs to be charged to increase its voltage to make it close to C1; if Uc1 < Uc2, it means that the voltage of C2 is too high, and C1 needs to be charged to balance the voltages of the two; if Uc1 = Uc2, it means that the voltage of the voltage equalization system has been balanced, maintain the current duty cycle, and set a proportional factor k to calculate the basic duty cycle adjustment amount. Specifically, it is based on the formula: ΔDbasic = k × ΔU, where ΔDbasic is the preliminary adjustment value without considering other factors, and its positive and negative signs are coordinated with the sign of ΔU and the direction of IL.

[0073] Further, the control module sets the dead-time compensation coefficient Kdt according to the dead-time deviation ΔTdead, and determines the duty-cycle compensation amount caused by the dead-time deviation, specifically according to the formula: ΔDdt = Kdt × ΔTdead, where ΔDdt represents the duty-cycle compensation amount. It should be noted that when the actual dead-time is greater than the designed value, that is, ΔTdead > 0, it means that the effective switching time is reduced. To make up for this deficiency, the duty cycle should be appropriately increased (or the adjustment amplitude should be reduced), and vice versa for corresponding correction.

[0074] Further, the control module uses an STM32 microcontroller in combination with a high-speed ADC module and a TMP36 temperature sensor, and then cooperates with a dedicated IGBT gate feedback circuit to obtain the current values of the key component parameters through real-time monitoring by the embedded software, compare them with the designed nominal values, obtain the parameter deviation index ΔP, and set the parameter compensation coefficient Kcomp to calculate the component parameter compensation amount, specifically according to the formula: ΔDcomp = Kcomp × ΔP, where ΔDcomp represents the component parameter compensation amount;

[0075] Further, the control module superimposes the adjustment amounts of each part to obtain the final duty-cycle adjustment amount ΔDtotal, specifically according to the formula: ΔDtotal = ΔDbasic + ΔDdt + ΔDcomp, and through the drive circuit, sends the duty cycles D1, D2 of the IGBT switch tubes to the corresponding IGBT drives in the power circuit to achieve the control of the voltage equalization circuit, so as to quickly reduce the voltage difference and improve the voltage equalization efficiency.

[0076] Further, when the voltage equalization system is in the off-grid working state or other working states that require voltage equalization adjustment, such as Figure 7 As shown, when D1 < D2, the circuit will be in the working state as shown in Figure 2 、 Figure 3 、 Figure 5 As shown; when When, the working state of the circuit is as shown in Figure 3 As shown; when When, the working state of the circuit is as shown in Figure 5 As shown; when (( Or ) When, the working state of the circuit is as shown in Figure 2 As shown. When the working state of the circuit is as shown in Figure 2 As shown, if I boost > 0, the circuit will charge C p , making its voltage U p Rise; if I boost < 0, the circuit will discharge C p , making its voltage U p Drop. Compared with the above state, if D1 > D2, the circuit will be in the state as shown in Figure 3 、 Figure 4 、 Figure 5 The working status shown is Figure 4 Middle U n Please refer to the above example for analysis.

[0077] Furthermore, the control module obtains the inductor current I through the sampling module. boost Determine whether the circuit is in the charging state or the discharging state, and then control the on and off of the IGBT through the driving circuit according to the duty cycle D1 and D2 calculated by DSP. Specifically, Q1 and Q2 control the charging process of the inductor; Q3 and Q4 control the discharging process of the inductor, changing the charging and discharging mode of the Boost circuit so that the voltages of C1 and C2 tend to be equal, thereby achieving the average voltage of the three electrodes at the output end.

[0078] The above formulas are all dimensionless and numerical calculations. The formulas are obtained by collecting a large amount of data and performing software simulation to obtain the most recent real situation. The preset parameters in the formulas are set by technicians in this field according to actual conditions.

[0079] The above embodiments may be implemented in whole or in part through software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments may be implemented in whole or in part in the form of a computer program product.

[0080] Those skilled in the art will appreciate that the modules and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application of the technical solution and the invention constraints. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0081] In addition, each functional module in each embodiment of the present application may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module.

[0082] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

[0083] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A three-electrode average voltage system at the output end of a bidirectional boost circuit, characterized in that: include: Sampling module, control module, and signal connection between modules; The sampling module is mainly used to accurately collect power data in the power circuit, including inductor current and low- and high-voltage side capacitor voltages; The control module is mainly used to dynamically adjust the IGBT duty cycle and dead time based on real-time feedback of temperature and switching delay.

2. The three-electrode average voltage system at the output end of a bidirectional boost circuit according to claim 1, characterized in that: The sampling module is designed for the inductor average current I that requires non-contact, fast response and high-precision isolation. boost , using a Hall effect sensor, connect the sensor in series or surround the conductor where the inductor is located so that it can capture the average current flowing through the inductor; and design an RC low-pass filter at the output end of the sensor to filter out high-frequency noise; For the low-voltage side capacitor voltage U that requires high accuracy and stability during measurement bat The sampling module combines the resistor voltage divider and filter to reduce the voltage to a safe range and then measures the low-voltage side capacitor voltage U bat Conduct collection; First, design a high-precision, low-drift resistor divider network, calculate the divider ratio, and select precision resistors to ensure a stable divider ratio with minimal error. Then, design an RC low-pass filter at the divider output to eliminate high-frequency noise. The high-voltage side capacitor voltage U is required to be measured under the premise of ensuring safe isolation. p 、U n ,The sampling module adopts a high-voltage resistant voltage divider network, supplemented by an isolation amplifier and filtering measures; First, high-voltage-resistant, precision resistors are selected to form a voltage divider network. The voltage divider ratio is calculated. After voltage division, a high-voltage isolation amplifier is added to the signal line. Independent voltage divider and isolation circuits are designed for the two capacitor terminals on the high-voltage side. An RC low-pass filter is added to the output of the isolation amplifier. After power data acquisition is completed, the sampling module connects the conditioned outputs of current, low-voltage capacitor voltage, and high-voltage side capacitor voltage to the multi-channel ADC inside the acquisition module, and designs overvoltage, overcurrent, and ESD protection circuits for each sampling path. Finally, the acquisition module converts the processed signals into digital data and outputs them to the control module through the standard interface SPI.

3. The three-electrode average voltage system at the output end of a bidirectional boost circuit according to claim 2, characterized in that: The control module presets an initial dead time value based on the switching delay of the IGBT device data and the safety margin determined by the experiment. In the control module initialization code, the initial value is written into the dead time register of the PWM timer. The control module uses a temperature sensor to collect current real-time temperature data through ADC, and performs feedback sampling on the switch signal to obtain actual switch delay data; The control module establishes an ideal dead time model based on temperature and calculates the ideal dead time under current conditions according to the formula: Tideal = T0 + Kt × (T-Tref), where Tideal represents the target dead time calculated based on the current temperature and other environmental conditions, T0 represents the baseline dead time, Tref represents the reference temperature, T represents the current real-time temperature, and Kt represents the temperature coefficient, which indicates the amount by which the ideal dead time needs to increase for every 1°C increase in temperature. The control module compares the actual measured switching delay Tmeas with the ideal value to obtain the error Error, which is based on the formula: Error = Tmeas - Tideal. When Error > 0, it means that the actual delay exceeds the ideal value, which will reduce switching efficiency. When Error < 0, it means that the actual delay is lower than the ideal value, which may pose a safety risk. The control module uses the PID control algorithm to dynamically adjust the dead time according to the dead time deviation. First, the dead time deviation ΔTdead is calculated. The specific formula is based on: Among them, Kp represents the proportional coefficient; Ki represents the integral coefficient; Kd represents the differential coefficient; The control module uses the current dead time Tdead,current and the dead time deviation ΔTdead to determine the new dead time according to the formula: Tdead,new = Tdead,current + ΔTdead, and updates it discretely at fixed time intervals Ts according to the formula: Discrete integral: Discrete differential: And substitute these discretized values into the PID formula; The control module calls the interface function of the corresponding PWM timer or directly accesses the register to write the Tdead,new value into the dead time register; it performs a synchronous update within the "safety window" of the PWM cycle. After the update, the control module verifies whether the new dead time has taken effect through feedback detection.

4. The three-electrode average voltage system at the output end of a bidirectional boost circuit according to claim 3, characterized in that: The control module calculates the voltage deviation ΔU of the high-side capacitor through the DSP, according to the formula: ΔU = Uc1-Uc2. The basic adjustment of the IGBT duty cycles D1 and D2 is determined based on the voltage deviation ΔU and the direction of the inductor current IL. If ΔU>0, it means that the voltage of C1 is too high and C2 needs to be charged to bring it close to C1. If ΔU<0, it means that the voltage of C2 is too high and C1 needs to be charged. A proportional factor k is set and the basic duty cycle adjustment is calculated according to the formula: ΔDbasic = k×ΔU, where ΔDbasic is the initial adjustment value without considering other factors, and its positive and negative signs match the sign of ΔU and the direction of IL. The control module sets the dead time compensation coefficient Kdt according to the dead time deviation ΔTdead, and determines the duty cycle compensation amount caused by the dead time deviation according to the formula: ΔDdt = Kdt × ΔTdead, where ΔDdt represents the duty cycle compensation amount; The control module uses an STM32 microcontroller with a high-speed ADC module and a TMP36 temperature sensor, and is equipped with a dedicated IGBT gate feedback circuit. The embedded software obtains the current values of key component parameters through real-time monitoring and compares them with the design nominal values to obtain the parameter deviation index ΔP. The parameter compensation coefficient Kcomp is then set to calculate the component parameter compensation amount. The specific formula is: ΔDcomp = Kcomp × ΔP, where ΔDcomp represents the component parameter compensation amount. The control module adds the adjustments of each part to obtain the final duty cycle adjustment value ΔDtotal, according to the formula: ΔDtotal = ΔDbasic + ΔDdt + ΔDcomp. The duty cycles D1 and D2 of the IGBT switches are then sent to the corresponding IGBT drivers in the power circuit through the driver circuit. The control module obtains the inductor current I through the sampling module boost Determine whether the circuit is in the charging state or the discharging state, and then control the on and off of the IGBT through the driving circuit according to the duty cycle D1, D2 calculated by DSP.

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