一种大功率高效率的开关电源电路
By combining the circuit structures of PFC and LLC modules and adopting parallel dual-MOSFET and multi-MOSFET parallel structures, the high-power switching power supply circuit was optimized, solving the problems of high switching losses and severe heat generation, and achieving high-efficiency power supply.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ZHONGSHAN BAOLIJIN ELECTRONICS
- Filing Date
- 2025-07-28
- Publication Date
- 2026-07-17
AI Technical Summary
Existing high-power switching power supply circuits with flyback structures suffer from high switching losses and severe heat generation, failing to meet the requirements for high power and high efficiency.
A circuit structure combining a PFC module and an LLC module is adopted. The PFC module uses a dual field-effect transistor parallel structure, while the output module uses multiple ultra-low internal resistance field-effect transistors in parallel. By optimizing the circuit through the combination of the PFC module and the LLC module, a low-harmonic, constant-voltage, and constant-current DC charging circuit is achieved.
It reduces the current stress of individual devices, reduces the power consumption and heat generation of MOSFETs, improves output efficiency, and meets the high efficiency requirements of high-power power supplies.
Smart Images
Figure CN224520931U_ABST
Abstract
Claims
1. A high power high efficiency switching power supply circuit, characterized by It includes an input module, a chip control module, and an output module. The output terminal of the input module is connected to the input terminal of the chip control module, and the output terminal of the chip control module is connected to the input terminal of the output module. A PFC module is connected between the input module and the chip control module, and an LLC module is connected between the chip control module and the output module.
2. The high-power high-efficiency switching power supply circuit according to claim 1, characterized in that The input module comprises an AC section, a rectification section, and a DC section. The AC section includes a live wire L and a neutral wire N, with a varistor MOV1 connected between the live wire L and the neutral wire N. A fuse F1 is connected in series with the live wire L. Common-mode inductors LF1 and LF2 are connected in series between the AC section and the rectification section. Resistors RX1, RX2, RX3, RX4, and capacitor CX1 are connected between the common-mode inductors LF1 and LF2. The rectification section includes a rectifier bridge BD1 and a rectifier bridge BD2 connected in parallel.
2. The input terminals of rectifier bridges BD1 and BD2 are simultaneously connected to the AC section, and the output terminals are simultaneously connected to the DC section. The DC section includes a common-mode inductor L2. The input terminal of the common-mode inductor L2 is connected to the rectifier section. Capacitors CB1 and CB2 are connected in parallel between the common-mode inductor L2 and the rectifier section. An inductor L1 is connected between capacitors CB1 and CB2. The output terminal of the common-mode inductor L2 is connected to the chip control module via diode D1. A resistor R3 and a capacitor C3 are connected in parallel with diode D1.
3. The high-power high-efficiency switching power supply circuit according to claim 2, characterized in that The chip control module includes a main control chip U1. Pins 9, 6, 10, 11, 14, and 15 of the main control chip U1 are connected to the LLC module. Pin 13 of the main control chip U1 is connected to the auxiliary winding of transformer T1. A capacitor C21, an electrolytic capacitor EC7, fast recovery diodes D6-D8, a resistor R28, and a resistor R29 are connected between pin 13 and the auxiliary winding. Pins 3, 5, and 8 of the main control chip U1 are connected to the PFC module. Pin 1 of the main control chip U1 is connected to the output terminal of the AC section through a resistor R16. Pin 16 of the main control chip U1 is connected to the output module through an optocoupler circuit.
4. The high-power high-efficiency switching power supply circuit according to claim 3, characterized in that The PFC module includes field-effect transistors Q8 and Q9. The drains of Q8 and Q9 are connected and then split into two paths: one path is connected to pin 8 of the main control chip U1, and the other path is connected to the output of the common-mode inductor L2. The sources of both Q8 and Q9 are grounded. The gate of Q8 is connected to pin 5 of the main control chip U1 through resistor R13, transistor Q4, and resistor R19. The gate of Q9 is split into two paths: one path is connected to pin 5 of the main control chip U1 through resistor R14, transistor Q4, and resistor R19, and the other path is connected to the gate of Q1 through switching diode D03 and resistor R1. The drain of Q1 is connected to relay RL1, and the control pin of relay RL1 is connected to the AC section.
5. The high-power high-efficiency switching power supply circuit according to claim 3, characterized in that The LLC module includes field-effect transistors Q10 and Q11. The gate of field-effect transistor Q10 is connected to pin 9 of the main control chip U1 through resistor R34, diode D11, and resistor R33. The drain of field-effect transistor Q10 is divided into two paths: one path is connected to pin 14 of the main control chip U1 through capacitors C26 and C20, and the other path is connected to the output terminal of common-mode inductor L2. The source of field-effect transistor Q10 is divided into two paths: one path is connected to pin 1 of transformer T1 through inductor Lr1, and the other path is connected to the drain of field-effect transistor Q11. The gate of field-effect transistor Q11 is connected to pin 6 of the main control chip U1 through resistor R31, diode D10, and resistor R30. The source of field-effect transistor Q11 is grounded. A fast recovery diode D9 is connected between pin 6 and pin 10 of the main control chip U1, and a capacitor C22 is connected between pin 10 and pin 11 of the main control chip U1.
6. The high-power high-efficiency switching power supply circuit according to claim 3, characterized in that The optocoupler circuit includes an optocoupler PC1. Pin 1 of the optocoupler PC1 is connected to pin 16 of the main control chip U1. Pin 2 of the optocoupler PC1 is grounded through resistor R36. A capacitor C27 is connected between pin 1 and pin 2 of the optocoupler PC1. Pin 3 of the optocoupler PC1 is connected to the output module through a switching diode D12. Pin 4 of the optocoupler PC1 is divided into two paths: one path is connected to the output module, and the other path is connected to the overvoltage protection circuit.
7. The high-power high-efficiency switching power supply circuit according to claim 6, characterized in that The overvoltage protection circuit includes an optocoupler PC2. The fourth pin of the optocoupler PC1 is connected to the fourth pin of the optocoupler PC2 through resistors R37 and R39. The third pin of the optocoupler PC2 is connected to the first pin of the voltage regulator U4. The second pin of the voltage regulator U4 is connected to the output module through resistor R41. The first pin of the optocoupler PC2 is connected to the 13th pin of the main control chip U1. The second pin of the optocoupler PC2 is connected to the gate of the field-effect transistor Q2. The drain of the field-effect transistor Q2 is connected to the output terminal of the common-mode inductor L2 through resistors R7 and R5.
8. The high-power high-efficiency switching power supply circuit of claim 1, wherein The output module includes a rectifier controller U2. The input terminal of the rectifier controller U2 is connected to the secondary winding of the transformer T1. Pin 7 of the transformer T1 is connected in parallel with MOSFETs Q12-Q15. The gates of MOSFETs Q12-Q15 are connected together and then connected to pin 8 of the rectifier controller U2 through resistor R51. The sources of MOSFETs Q12-Q15 are connected together and then connected to pin 5 of the rectifier controller U2. Pin 12 of the transformer T1 is connected in parallel with... The output module includes a common-mode inductor LF4. A filter circuit consisting of a resistor R53, capacitors C31-C37, and electrolytic capacitors CE8-CE3 is connected between the rectifier U2 and the gates of the MOSFETs Q16-Q19. The sources of the MOSFETs Q12-Q15 are connected to the rectifier U2 and then to the rectifier U2. The output module also includes a common-mode inductor LF4. A filter circuit consisting of a resistor R53, capacitors C31-C37, and electrolytic capacitors CE8-CE3 is connected between the rectifier U2 and the common-mode inductor LF4.