An energy recovery power supply system based on three-phase electric energy conversion

Abstract

This invention discloses an energy recovery power supply system based on three-phase power conversion. The system includes a three-phase inverter module, a three-phase active rectifier module, a sampling and detection module, an MCU core processing module, a drive isolation module, a protection circuit module, and an auxiliary power supply module. The system takes a 60V DC input and outputs a 50Hz three-phase AC power with an effective line voltage of 32V via the three-phase inverter, using SPWM modulation and PID control. Voltage and current are fed back through sampling and detection, and energy is fed back through active rectification. The system is stable, has low harmonics, and strong load adjustment capability. Experiments demonstrate its stable output and feedback function, simple and reliable structure, and suitability for power electronics testing and other scenarios.

Description

Technical Field

[0001] This invention relates to the fields of switching power supply technology, pulse width modulation technology, closed-loop control technology and electrical automation, and specifically to an energy recovery power supply system based on three-phase power conversion for energy feedback and power quality optimization in power electronics experiments and the development of small and medium power systems. Background Technology

[0002] With the rapid development of power electronics technology, new energy technology, and intelligent testing equipment, inverter power supplies are widely used in new energy power generation, motor drives, power electronics experimental platforms, and industrial testing equipment. During the testing and operation of these devices, inverters are typically used to convert DC power into AC power for the load. However, traditional power systems consume most of the energy generated during load operation as heat, resulting in low energy utilization and high operating costs.

[0003] In recent years, energy conservation, emission reduction, and efficient energy utilization have become important research directions in the field of power electronics. Energy recovery technology can feed back a portion of the electrical energy consumed on the load side to the power supply side, achieving energy recycling, thereby improving overall system efficiency and reducing equipment operating losses. Currently, although some industrial-grade energy feedback devices can achieve energy recovery, they generally suffer from problems such as complex system structure, high control difficulty, high equipment cost, and difficulty in applying them to small and medium power scenarios.

[0004] Furthermore, key technical challenges need to be addressed simultaneously during the inverter and energy feedback processes, including stable AC output control, real-time voltage and current monitoring, and stable transmission of feedback energy. Therefore, designing an energy recovery power supply system that combines three-phase AC output and energy recovery functions, features a simple structure, stable operation, and is suitable for small to medium power applications is of great significance for improving energy efficiency and promoting the energy-saving development of power electronic equipment. Summary of the Invention

[0005] The purpose of this invention is to provide an energy recovery power supply system based on three-phase power conversion. This system combines three-phase inverter technology, active rectification technology, and closed-loop control technology. Addressing the problem of low energy utilization and load energy consumption as heat during traditional inverter power supply testing, this invention proposes a power conversion solution with energy feedback functionality. This invention achieves stable three-phase AC output and energy recovery. It monitors the system's operating status in real time through a sampling and detection module and improves system stability and energy utilization efficiency through a closed-loop control strategy.

[0006] The specific technical solution for achieving the objective of this invention is as follows:

[0007] An energy recovery power supply system based on three-phase power conversion includes a three-phase inverter module, a three-phase active rectifier module, a sampling and detection module, an MCU core processing module, a drive isolation module, a protection circuit module, and an auxiliary power supply module.

[0008] The three-phase inverter module is connected to the three-phase active rectifier module, the sampling and detection module, the drive isolation module, and the protection circuit module, respectively.

[0009] The three-phase active rectifier module is connected to the three-phase inverter module, the sampling and detection module, and the drive isolation module, respectively.

[0010] The sampling and detection module is connected to the three-phase inverter module, the three-phase active rectifier module, and the MCU core processing module, respectively.

[0011] The drive isolation module is connected to the three-phase inverter module, the three-phase active rectifier module, the auxiliary power supply module, and the MCU core processing module, respectively.

[0012] The auxiliary power module is connected to the drive isolation module and the protection circuit module respectively;

[0013] The protection circuit module is connected to the three-phase inverter module, the auxiliary power supply module and the MCU core processing module respectively.

[0014] The MCU core processing module is connected to the sampling and detection module, the drive isolation module, and the protection circuit module, respectively.

[0015] The sampling and detection module is used to collect the output voltage and current signals of the three-phase inverter module and the DC bus voltage signal.

[0016] The MCU core processing module acquires data from the sampling and detection module and generates control signals based on the sampling results. These signals then drive the three-phase inverter module and the three-phase active rectifier module to operate through the drive isolation module.

[0017] The three-phase inverter module is used to convert the DC input voltage into a three-phase AC voltage output with a frequency of 50Hz.

[0018] The three-phase active rectifier module is used to rectify and feed back the AC side energy, and then transmit the fed-back energy to the DC bus side to realize the recycling of electrical energy.

[0019] The MCU core processing module calls SPWM modulation to generate an inverter control signal and calls PID closed-loop control to adjust the output voltage in real time, thereby achieving stable control of the three-phase AC output voltage. The MCU core processing module is an STM32F407 microcontroller, which includes an ADC module, a timer module, and a communication interface module. The MCU core processing module obtains data from the sampling and detection module through the ADC module and outputs the SPWM control signal through the timer module.

[0020] The protection circuit module is used to implement overcurrent protection, overvoltage protection and overtemperature protection;

[0021] The auxiliary power module is used to provide isolated power to each module.

[0022] Furthermore, the three-phase inverter module adopts a three-phase half-bridge topology, including several MOSFET power switches and an LC output filter circuit. The DC input voltage is 48-60V, and after SPWM modulation, the output line voltage is 32V and the frequency is 50Hz, which is a three-phase AC power.

[0023] Furthermore, the drive isolation module includes an isolation drive chip and a bootstrap drive circuit, which processes the PWM control signal generated by the MCU core processing module and then drives the MOSFET power switches in the three-phase inverter module and the three-phase active rectifier module.

[0024] Furthermore, the sampling and detection module includes a voltage sampling circuit and a current sampling circuit. The voltage sampling circuit uses an isolation amplifier, and the current sampling circuit uses a Hall current sensor to realize the real-time detection of system operating parameters.

[0025] Furthermore, the three-phase active rectifier module adopts PWM rectification control mode, which adjusts the power flow direction according to the AC side voltage and current information to realize the feedback of AC side power to DC bus side.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] (1) The present invention adopts a structure combining three-phase inverter and active rectification to realize three-phase AC output and energy feedback function, reduce power loss during the test, and improve the system energy utilization efficiency;

[0028] (2) The present invention uses STM32F407 as the control core, and combines SPWM modulation and PID closed-loop control strategy to achieve stable control of output voltage, thereby improving the dynamic response performance and operational stability of the system.

[0029] (3) The present invention uses AMC1301 isolation voltage sampling and CC6920 Hall current sampling to realize real-time detection of voltage and current parameters and improve the system control accuracy;

[0030] (4) The present invention adopts the UCC21520 isolation drive scheme to realize electrical isolation between the control circuit and the power circuit, thereby improving the system safety and reliability;

[0031] (5) The present invention has a simple structure and low cost, and is suitable for power electronics experimental platforms, inverter power supply testing devices and small and medium power energy feedback scenarios. Attached Figure Description

[0032] Figure 1 This is a structural block diagram of the present invention;

[0033] Figure 2 This is a flowchart illustrating the workflow of the present invention. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0035] Example

[0036] See Figure 1 This embodiment includes a three-phase inverter module 1, a three-phase active rectifier module 2, a sampling and detection module 3, a drive isolation module 4, an auxiliary power supply module 5, a protection circuit module 6, and an MCU core processing module 7.

[0037] The three-phase inverter module 1 is connected to the three-phase active rectifier module 2, the sampling and detection module 3, the drive isolation module 4, and the protection circuit module 6, respectively.

[0038] The three-phase active rectifier module 2 is connected to the three-phase inverter module 1, the sampling and detection module 3, and the drive isolation module 4, respectively.

[0039] The sampling and detection module 3 is connected to the three-phase inverter module 1, the three-phase active rectifier module 2, and the MCU core processing module 7, respectively.

[0040] The drive isolation module 4 is connected to the three-phase inverter module 1, the three-phase active rectifier module 2, the auxiliary power supply module 5, and the MCU core processing module 7, respectively.

[0041] The auxiliary power supply module 5 is connected to the drive isolation module 4 and the protection circuit module 6 respectively;

[0042] The protection circuit module 6 is connected to the three-phase inverter module 1, the auxiliary power supply module 5, and the MCU core processing module 7, respectively.

[0043] The MCU core processing module 7 is connected to the sampling and detection module 3, the drive isolation module 4, and the protection circuit module 6, respectively.

[0044] In this embodiment, the system input uses a 60V DC power supply to provide DC bus voltage for the three-phase inverter module 1 and input power for the auxiliary power supply module 5.

[0045] The three-phase inverter module 1 in this embodiment includes a three-phase half-bridge inverter circuit and an LC filter circuit. The three-phase half-bridge inverter circuit consists of a three-phase bridge arm structure composed of six MOSFET power switches. Under the action of the PWM control signal output by the drive isolation module 4, it converts the 60V DC voltage into a three-phase AC voltage. After the LC filter circuit filters out high-frequency harmonics, it outputs a three-phase AC voltage with a frequency of 50Hz and an effective line voltage of 32V.

[0046] The three-phase active rectifier module 2 of this embodiment adopts a three-phase bridge PWM rectifier structure. Its AC side is connected to the output terminal of the three-phase inverter module 1, and its DC side is connected to the system DC bus. The three-phase active rectifier module 2 can convert the remaining AC power back into DC power and feed it back to the DC bus, realizing the recycling of electrical energy.

[0047] The sampling and detection module 3 in this embodiment includes a voltage sampling circuit and a current sampling circuit. The voltage sampling circuit uses an AMC1301 isolation amplifier. The voltage to be measured is divided by resistors and then input to the AMC1301 for isolation and amplification. The current sampling circuit uses a CC6920 Hall current sensor for current detection. The sampled signal is conditioned by an operational amplifier and converted into a 0-3.3V voltage signal, which is then input to the MCU core processing module 7 for processing.

[0048] The drive isolation module 4 in this embodiment includes a UCC21520 isolation drive chip and a bootstrap drive circuit. The PWM control signal output by the MCU core processing module 7 is electrically isolated and amplified by the drive isolation module 4, and then drives the MOSFET power switching devices in the three-phase inverter module 1 and the three-phase active rectifier module 2 to operate.

[0049] The auxiliary power supply module 5 in this embodiment includes a multi-channel voltage regulator circuit that converts the 60V input voltage into 3.3V, 5V and 12V output voltages to provide working power for the drive isolation module 4 and the protection circuit module 6.

[0050] The protection circuit module 6 in this embodiment includes an overcurrent protection circuit, an overvoltage protection circuit, and an overtemperature protection circuit. When the system detects an abnormal operating state, the protection circuit module 6 sends a fault signal to the MCU core processing module 7, which then shuts down the PWM output to ensure safe system operation.

[0051] In this embodiment, the MCU core processing module 7 uses an STM32F407 microcontroller, which internally includes an ADC sampling module, a timer module, and a communication module. After the sampling and detection module 3 collects the system operating parameters, it sends them to the ADC sampling module. The MCU core processing module 7 compares the sampled values ​​with the reference values ​​through a PID closed-loop control algorithm and adjusts the SPWM modulation ratio in real time to generate a PWM control signal that is output to the drive isolation module 4, thereby realizing stable control of the system output voltage and energy feedback control.

[0052] During system operation, the DC input power supply provides DC energy to the three-phase inverter module 1, which converts the DC power into three-phase AC power for the load. When there is residual energy at the load end, the three-phase active rectifier module 2 converts the AC energy back into DC power and feeds it back to the DC bus. The sampling and detection module 3 monitors the system's operating status in real time, and the MCU core processing module 7 adjusts the control parameters based on the sampling results to achieve stable three-phase AC output and energy recovery functions.

[0053] See Figure 2 , Figure 2 This is a flowchart illustrating the workflow of the present invention. The working process of the energy recovery power system of the present invention includes steps such as system initialization, parameter initialization, inverter control, energy feedback control, fault detection, and main cycle operation.

[0054] After the system is powered on, it first enters the system initialization phase, which configures hardware resources such as GPIO interfaces, timers, ADC sampling modules, and interrupt systems, and completes the initialization of each functional module to provide a basic operating environment for the normal operation of the system.

[0055] After system initialization is complete, the parameter initialization phase begins, where SPWM modulation parameters, PID controller parameters, and system reference voltage are configured to establish initial operating conditions for subsequent closed-loop control.

[0056] After parameter initialization, the system enters normal operation. The MCU core processing module collects operating parameters such as system output voltage, output current, and bus voltage in real time, and completes data sampling through ADC. The sampling results are sent to the closed-loop control algorithm for calculation, and the algorithm adopts the PID closed-loop control algorithm.

[0057] The closed-loop control algorithm performs PID adjustment based on the deviation between the output voltage and the reference voltage, calculates the SPWM modulation duty cycle, and generates a three-phase SPWM drive signal by a timer. The signal is then output to the three-phase inverter module through the drive isolation module to achieve a stable three-phase AC voltage output.

[0058] When the system meets the energy feedback conditions, the energy feedback control function is activated. The MCU core processing module controls the three-phase active rectifier module based on the collected AC side voltage, current, and phase information, generating a rectifier PWM drive signal to convert the remaining AC side energy into DC power and feed it back to the DC bus, thus realizing energy recovery and utilization.

[0059] During system operation, the fault detection module continuously monitors the system's operating status and makes real-time judgments on abnormal conditions such as overcurrent, overvoltage, and overtemperature. When a fault is detected, fault protection is immediately executed, shutting down the PWM output, stopping the inverter and rectifier control, and simultaneously outputting fault alarm information, causing the system to enter a shutdown protection state.

[0060] If the system does not detect a fault, it updates the PID control parameters and SPWM output duty cycle based on the real-time sampling results, and enters the main loop to continue executing data sampling, closed-loop control, energy feedback control and fault detection, thereby realizing the system output voltage stabilization control and energy recovery functions.

Claims

1. An energy recovery power supply system based on three-phase power conversion, characterized in that, The system includes a three-phase inverter module, a three-phase active rectifier module, a sampling and detection module, an MCU core processing module, a drive isolation module, a protection circuit module, and an auxiliary power supply module; The three-phase inverter module is connected to the three-phase active rectifier module, the sampling and detection module, the drive isolation module, and the protection circuit module, respectively. The three-phase active rectifier module is connected to the three-phase inverter module, the sampling and detection module, and the drive isolation module, respectively. The sampling and detection module is connected to the three-phase inverter module, the three-phase active rectifier module, and the MCU core processing module, respectively. The drive isolation module is connected to the three-phase inverter module, the three-phase active rectifier module, the auxiliary power supply module, and the MCU core processing module, respectively. The auxiliary power module is connected to the drive isolation module and the protection circuit module respectively; The protection circuit module is connected to the three-phase inverter module, the auxiliary power supply module and the MCU core processing module respectively. The MCU core processing module is connected to the sampling and detection module, the drive isolation module, and the protection circuit module, respectively. The sampling and detection module is used to collect the output voltage and current signals of the three-phase inverter module and the DC bus voltage signal. The MCU core processing module acquires data from the sampling and detection module and generates control signals based on the sampling results. These signals then drive the three-phase inverter module and the three-phase active rectifier module to operate through the drive isolation module. The three-phase inverter module is used to convert the DC input voltage into a three-phase AC voltage output with a frequency of 50Hz. The three-phase active rectifier module is used to rectify and feed back the AC side energy, and then transmit the fed-back energy to the DC bus side to realize the recycling of electrical energy. The MCU core processing module calls SPWM modulation to generate an inverter control signal and calls PID closed-loop control to adjust the output voltage in real time, thereby achieving stable control of the three-phase AC output voltage. The MCU core processing module is an STM32F407 microcontroller, which includes an ADC module, a timer module, and a communication interface module. The MCU core processing module obtains data from the sampling and detection module through the ADC module and outputs the SPWM control signal through the timer module. The protection circuit module is used to implement overcurrent protection, overvoltage protection and overtemperature protection; The auxiliary power module is used to provide isolated power to each module.

2. The energy recovery power system according to claim 1, characterized in that, The three-phase inverter module adopts a three-phase half-bridge topology, including several MOSFET power switches and an LC output filter circuit. The DC input voltage is 48-60V, and after SPWM modulation, the output line voltage is 32V and the frequency is 50Hz, which is a three-phase AC power.

3. The energy recovery power system according to claim 1, characterized in that, The drive isolation module includes an isolation drive chip and a bootstrap drive circuit, which processes the PWM control signal generated by the MCU core processing module and then drives the MOSFET power switches in the three-phase inverter module and the three-phase active rectifier module.

4. The energy recovery power system according to claim 1, characterized in that, The sampling and detection module includes a voltage sampling circuit and a current sampling circuit. The voltage sampling circuit uses an isolation amplifier, and the current sampling circuit uses a Hall current sensor to realize the real-time detection of system operating parameters.

5. The energy recovery power system according to claim 1, characterized in that, The three-phase active rectifier module adopts PWM rectification control mode, which adjusts the power flow direction according to the AC side voltage and current information to realize the feedback of AC side power to DC bus side.

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