DC-DC power conversion circuit and control method thereof
By combining a multi-winding isolation transformer and an intelligent control module, the output voltage instability problem of traditional DC-DC power conversion circuits under complex loads is solved, and efficient and stable power conversion is achieved. It is suitable for automotive electronic equipment, industrial automation control equipment and renewable energy utilization systems.
Patent Information
- Application Number
- CN202510784319.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-12
- Publication Date
- 2025-09-16
AI Technical Summary
Traditional DC-DC power conversion circuits have poor output voltage stability when facing complex load changes, making it difficult to meet the efficient and stable power conversion requirements of modern electronic devices. In particular, they are inefficient under light or medium load conditions, and it is difficult to achieve precise power control and adaptive regulation.
It uses a multi-winding isolation transformer and an intelligent control module, combined with input filtering and output rectifier filtering modules. The intelligent control module collects and analyzes circuit data in real time, dynamically adjusts the working state of the switch tube group, and achieves efficient and stable voltage conversion.
It improves the flexibility and adaptability of the circuit, enhances the electrical isolation and anti-interference capabilities, ensures the stable operation of the circuit under different loads and working conditions, and achieves high-efficiency and high-precision DC voltage conversion.
Smart Images
Figure CN120658111A_ABST
Abstract
Claims
1. A DC-DC power conversion circuit, characterized in that: The circuit includes an input filter module, a multi-winding isolation transformer, a switch tube group, an output rectifier filter module and an intelligent control module; The input filtering module is used to filter the DC input power supply to obtain a first DC power; The multi-winding isolation transformer comprises a primary winding and a plurality of secondary windings, wherein the secondary winding is used to generate a second alternating current according to the first alternating current flowing through the primary winding; The switch tube group includes a main power switch tube and multiple auxiliary regulation switch tubes. One end of the primary winding is connected to the input filter module, and the other end of the primary winding is connected to the main power switch tube. The main power switch tube is used to convert the first direct current into the first alternating current. Each secondary winding is connected to a corresponding auxiliary regulation switch tube. The auxiliary regulation switch tube is used to control energy transfer between the primary winding and the secondary winding. The output rectification and filtering module is connected to the secondary winding, and is used to rectify and filter the second alternating current to obtain a direct current output power supply; The intelligent control module is connected to the switch tube group. The intelligent control module is used to collect operating data of the target power conversion circuit and intelligently control the conduction and shutdown of the switch tube group based on the operating data. The operating data includes input voltage, output voltage, load current and circuit temperature.
2. The circuit according to claim 1, wherein: The primary winding and the plurality of secondary windings are wound in a segmented manner, and an insulating layer and a magnetic shielding layer are provided between adjacent windings.
3. The circuit according to any one of claims 1 or 2, characterized in that The intelligent control module drives the main power switch tube through zero voltage switching technology or zero current switching technology, and the driving circuit of the main power switch tube includes a resonant inductor and a resonant capacitor; the intelligent control module adjusts the duty cycle of the auxiliary regulating switch tube through pulse width modulation technology to regulate the output voltage.
4. The circuit according to claim 3, characterized in that The intelligent control module includes: an information acquisition module, configured to acquire the input voltage, the output voltage, the load current, and the circuit temperature; An adaptive pulse width modulation controller, configured to dynamically adjust the pulse width and pulse frequency of the switch tube group according to the input voltage, the output voltage, and the load current; A fuzzy logic-sliding mode variable structure controller is used to combine fuzzy logic rules with sliding mode variable structure control technology to improve the robustness of the target power conversion circuit to load disturbances and parameter changes, accelerate the transient response speed of the output voltage, and suppress overshoot and oscillation of the output voltage; a multi-objective optimization power divider, configured to allocate an energy transfer ratio between the primary winding and the plurality of secondary windings based on energy transfer characteristics of the multi-winding isolation transformer, thereby achieving a balance between multiple target dimensions, wherein the target dimension includes at least one of energy conversion efficiency, power density, and heat dissipation performance of the target power conversion circuit; The protection control module is used to monitor the circuit temperature and the stress information of the switch tube group, and trigger the protection mechanism of the target power conversion circuit when an abnormal state is detected.
5. The circuit according to claim 1, wherein: The output rectifier filter module is composed of an LC filter circuit; the inductance and capacitance of the LC filter circuit are designed according to the operating range of the output voltage and the load current, so that the ripple factor of the output voltage is less than or equal to 1%.
6. A control method, characterized in that: The method is applied to the DC-DC power conversion circuit according to any one of claims 1 to 5, and the method comprises: Collecting operating data of the target power conversion circuit, the operating data including input voltage, output voltage, load current and circuit temperature; Classifying the load operating condition of the target power conversion circuit into a light load mode, a medium load mode, and a heavy load mode according to a comparison result of the current amplitude of the load current and a load threshold, and analyzing a current variation trend of the load current; Determining feedforward control parameters according to the input voltage and the load condition, the feedforward control parameters including an initial on-time and an initial dead-time of the switch group, and an energy distribution coefficient of each of the secondary windings in the multi-winding isolation transformer; Performing real-time closed-loop control on the on and off processes of the switch tube group according to the error between the output voltage and the target output voltage, and the current variation trend; The circuit temperature and the stress information of the switch tube group are monitored, and when an abnormal state is detected, a protection mechanism of the target power conversion circuit is triggered.
7. The method according to claim 6, characterized in that The collecting of the operating data of the target power conversion circuit includes at least one of the following: Use high-precision sensors and signal conditioning circuits to filter, amplify and perform analog-to-digital conversion on the collected analog signals; Based on a data buffer and a multi-level interrupt processing mechanism, the operating data is collected.
8. The method according to claim 6, characterized in that The analyzing the current variation trend of the load current includes: The load current is analyzed by using a sliding window averaging method and a differential algorithm, and the rate of change and trend parameters of the load current are calculated.
9. The method according to claim 6, characterized in that The determining of the feedforward control parameter according to the input voltage and the load condition includes at least one of the following: Matching and searching the feedforward control parameters through a pre-stored parameter mapping table, wherein the parameter mapping table includes target feedforward control parameters under different circuit operating condition combinations, wherein the circuit operating condition combinations include input voltage operating conditions and load operating conditions; A preset mathematical model is used to obtain the input voltage and the load condition, and calculate the feedforward control parameters.
10. The method according to claim 6, characterized in that The performing real-time closed-loop control on the on and off process of the switch tube group according to the error between the output voltage and the target output voltage and the current change trend includes: A fuzzy logic-sliding mode variable structure controller is used to adjust the duty cycle and switching frequency of the switch group so that the output voltage tracks the target output voltage and ensures that the fluctuation range of the output voltage is controlled within a preset tolerance range when the load current changes.