Dual drive voltage conversion system

Abstract

The application provides a double-drive voltage conversion system, which comprises a voltage conversion circuit and a control module, wherein the voltage conversion circuit comprises an input unit, an output unit, an output control unit and a conversion transformer; the output control unit comprises a conversion control chip, a conversion drive switch tube and a conversion control chip drive circuit; the conversion control drive circuit comprises a chip drive switch tube, a software drive optocoupler, a hardware drive switch tube, an external trigger button and a hardware drive optocoupler. In the double-drive voltage conversion system provided by the application, a software control signal can be sent out by the control module, a trigger signal and a hardware control signal can be sent out by the external trigger button, and the priority of the trigger signal is higher than that of the software control signal, so that the user does not need to redesign the software control signal due to special scenes.

Description

Technical Field

[0001] This invention relates to the field of circuit technology, and in particular to a dual-drive voltage conversion system. Background Technology

[0002] In industrial control systems, power conversion sustaining circuits are widely used to achieve system power-on startup, operation sustaining, and power-off reset. In traditional solutions, system startup and sustaining control mainly rely on the software logic of a microcontroller (MCU).

[0003] Specifically, pure software control schemes typically utilize the MCU's GPIO ports to directly drive the power switching transistors (such as MOSFETs or bipolar transistors). After the system powers on, the MCU completes initialization and detects status parameters such as battery voltage and temperature. If the conditions are met, it outputs a high-level signal to latch the power conversion sustaining circuit, achieving software self-locking sustaining.

[0004] In certain applications (such as equipment debugging, maintenance, or emergency shutdown scenarios), users need to temporarily change the power supply status. In existing technologies, the typical control method is as follows: the user sends a specific control command to the MCU via a physical button. Upon receiving the command, the MCU modifies or switches the currently running control rules in real time at the software level, and then executes the power supply on / off operation according to the modified rules. Since each manual intervention requires software to parse rules, save states, and switch logic, the operation process is complex, increasing not only the complexity of software design but also the probability of human error.

[0005] Therefore, there is a need to provide a dual-drive voltage conversion system that facilitates switching between software and hardware control. Summary of the Invention

[0006] This invention provides a dual-drive voltage conversion system that allows for convenient switching between software and hardware control, effectively solving the technical problems of high software design complexity and complicated operation procedures for switching between software and hardware control in existing voltage conversion systems.

[0007] This invention provides a dual-drive voltage conversion system, which includes a voltage conversion circuit and a control module; wherein the voltage conversion circuit includes: The input unit is used to connect to the conversion power supply; The output unit is used to output a stable converted power supply voltage to the DC bus; An output control unit is configured to control the on / off state of the input unit based on the conversion drive signal from the control module; and The conversion transformer is connected to the input unit, output unit, and output control unit respectively, and is used to convert the power supply voltage. The output control unit includes: The conversion control chip is used to generate control signals for driving the conversion switching transistor; A conversion drive switch, connected to the conversion transformer, is used to start the conversion transformer based on the control signal; and A conversion control chip driving circuit is used to generate the driving voltage of the conversion control chip; The conversion control chip drive circuit includes: The chip drives the switching transistor, whose input terminal is connected to the conversion power supply, and whose output terminal is connected to the power supply terminal of the conversion control chip. A software-driven optocoupler has its input end connected to the control module and its output end connected to the control end of the chip-driven switching transistor, and is used to provide the software control signal output by the control module. The hardware-driven switching transistor has its input terminal connected to the control terminal of the chip-driven switching transistor, its output terminal connected to the negative terminal of the conversion power supply, and its control terminal receiving hardware control signals. When the hardware-driven switching transistor is turned on, it forcibly pulls the potential of the control terminal of the chip-driven switching transistor to close to the negative terminal potential, so that the software-driven optocoupler does not change the potential of the control terminal regardless of whether it is turned on or off. An external trigger button is used to send the hardware control signal; and A hardware-driven optocoupler is used to send the hardware control signals to the control module; The control module outputs the software control signal in response to receiving the hardware control signal; the control module performs the reset operation of the external trigger button only after confirming that the software control signal is effective, otherwise it maintains the trigger state of the external trigger button to keep the hardware drive path open.

[0008] In the dual-drive voltage conversion system of this embodiment, the input unit is provided with a conversion power detection pin connected to the control module. When the dual-drive voltage conversion system is in software control mode, the control module determines to send a software control signal to the software-driven optocoupler through the detection signal of the conversion power detection pin, driving the chip-driven switch to turn on, thereby driving the conversion control chip and the conversion transformer to work normally. When the dual-drive voltage conversion system is hardware-driven through the external trigger button, the external trigger button sends the trigger signal, driving the hardware-driven switch and the chip-driven switch to turn on, thereby driving the conversion control chip and the conversion transformer to work normally.

[0009] In the dual-drive voltage conversion system of this embodiment, when the dual-drive voltage conversion system is hardware driven by the external trigger button, the external trigger button sends the trigger signal, which drives the hardware drive optocoupler to send the hardware control signal to the control module; the control module synchronously sends the software control signal based on the hardware control signal, and the software control signal is used to drive the chip drive switch to turn on.

[0010] In the dual-drive voltage conversion system of this embodiment, if the control module synchronously sends the software control signal based on the hardware control signal, the external trigger button will be reset; if the control module receives the hardware control signal but does not send the software control signal, the external trigger button will not be operated.

[0011] In the dual-drive voltage conversion system of this embodiment, the conversion transformer includes an input winding, an output winding, and a control winding. The input winding is connected to the input unit and the output control unit, the output winding is connected to the output unit, and the control winding outputs a stable reference voltage. The control terminal of the conversion drive switch is connected to the output terminal of the conversion control chip, the input terminal of the conversion drive switch is connected to the input winding, and the output terminal of the conversion drive switch is grounded. The power supply terminal of the conversion control chip is connected to the conversion power supply and the stable reference voltage through the conversion control chip drive circuit.

[0012] In the dual-drive voltage conversion system of this embodiment, the chip-driven switch is a PNP transistor. The emitter of the chip-driven switch is connected to both the conversion power supply and the stable reference voltage, and the collector of the chip-driven switch is connected to the power supply terminal of the conversion control chip. The positive terminal of the software-driven optocoupler is connected to a 5V power supply through a current-limiting resistor, the negative terminal of the software-driven optocoupler is connected to the software control signal output by the control module, the emitter of the software-driven optocoupler is grounded, and the collector of the software-driven optocoupler is connected to the base of the chip-driven switch. The hardware-driven switch is an NPN transistor. The collector of the hardware-driven switch is connected to the control terminal of the chip-driven switch, the emitter of the hardware-driven switch is grounded, and the base of the hardware-driven switch is connected to an external power supply through an external trigger button. The positive terminal of the hardware-driven optocoupler is connected to an external power supply through the external trigger button, the negative terminal of the hardware-driven optocoupler is grounded, the emitter of the hardware-driven optocoupler is connected to the control module, and the collector of the hardware-driven optocoupler is connected to a 5V power supply through a current-limiting resistor.

[0013] In the dual-drive voltage conversion system of this embodiment, the base of the hardware drive switch is also connected to the conversion power supply and the stable reference voltage respectively through the external trigger button.

[0014] In the dual-drive voltage conversion system of this embodiment, the conversion control chip further includes a feedback terminal, which is connected to the stable reference voltage through a current-limiting resistor.

[0015] In the dual-drive voltage conversion system of this embodiment, the conversion control chip drive circuit further includes a conversion power switch transistor, which is a PNP transistor. The collector of the conversion power switch transistor is connected to the conversion power supply through a current-limiting resistor, the emitter of the conversion power switch transistor is connected to the emitter of the chip drive switch transistor, and the base of the conversion power switch transistor is connected to the conversion power supply. At the same time, the base of the conversion power switch transistor is also grounded through a Zener diode, wherein the anode of the Zener diode is grounded, and the cathode of the Zener diode is connected to the base of the conversion power switch transistor.

[0016] In the dual-drive voltage conversion system of this embodiment, the conversion control chip drive circuit further includes an energy storage capacitor. One end of the energy storage capacitor is connected to the emitter of the chip drive switch, and the other end of the energy storage capacitor is grounded.

[0017] Compared to existing technologies, the advantages of this invention are as follows: In the dual-drive voltage conversion system provided by this invention, software control signals can be issued through the control module, and trigger signals and hardware control signals can be issued through an external trigger button. The trigger signal has a higher priority than the software control signal (i.e., when the hardware-driven switching transistor is turned on, it directly bypasses the control action of the software-driven optocoupler, forcibly pulling down the base potential of the chip-driven switching transistor, thereby achieving physical coverage of software control by hardware triggering). Existing pure software self-locking schemes cannot start when MCU initialization fails / program crashes, and manual intervention requires firmware modification; this invention bypasses the MCU to complete the startup through a pure hardware path, and then uses an optocoupler handshake to transfer control to the software, balancing emergency stop / debugging and steady-state intelligent management; effectively solving the technical problems of high software design complexity and complex operation procedures for switching between software and hardware control in existing voltage conversion systems. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments are briefly introduced below. The drawings described below are only the corresponding drawings of some embodiments of the present invention.

[0019] Figure 1 This is a schematic diagram of an embodiment of the dual-drive voltage conversion system of the present invention; Figure 2This is a schematic diagram of the voltage conversion circuit of the dual-drive voltage conversion system of the present invention. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] In the diagram, units with similar structures are represented by the same labels.

[0022] The dual-drive voltage conversion system of this invention can be installed in various power conversion systems and power drive systems to determine whether to use a power supply to power the bus based on the current operating status of the power supply. Therefore, both software and hardware switching can be performed on the current power supply. Software switching involves the control module determining whether the current power supply is suitable for power supply operation. The control module considers not only the current power supply's parameters but may also compare the parameters of other power supplies, selecting the one that meets the requirements to power the bus. Hardware switching, on the other hand, involves manual judgment by operators based on the current situation to switch power supplies. Because the hardware switching channel is completely different from the software switching channel, if the software switching channel of the control module malfunctions, operators can still perform power switching operations through the hardware switching channel.

[0023] Please refer to the details. Figure 1 and Figure 2 , Figure 1 This is a schematic diagram of an embodiment of the dual-drive voltage conversion system of the present invention; Figure 2 This is a schematic diagram of the voltage conversion circuit of the dual-drive voltage conversion system of the present invention. The dual-drive voltage conversion system of this embodiment includes a voltage conversion circuit 10 and a control module 20. The control module 20 is used to interactively drive the corresponding conversion power supply 15 to output a stable conversion power supply voltage to the DC bus.

[0024] The voltage conversion circuit 10 includes an input unit 11, an output unit 12, an output control unit 14, and a conversion transformer 13. The input unit 11 is used to connect to the conversion power supply 15. The output unit 12 is used to output a stable conversion power supply voltage to the DC bus. The output control unit 14 is used to control the on / off state of the input unit 11 based on the conversion drive signal of the control module 20. The conversion transformer 13 is connected to the input unit 11, the output unit 12, and the output control unit 14 respectively, and is used to perform voltage conversion operation on the conversion power supply 15.

[0025] The output control unit 14 includes a conversion control chip 141, a conversion drive switch 142, and a conversion control chip drive circuit 143. The conversion control chip 141 generates control signals for the conversion drive switch 142. The conversion drive switch 142 is connected to the conversion transformer 13 and is used to start the conversion transformer 13 based on the control signals. The conversion control chip drive circuit 143 controls the conversion power supply voltage BATIN and the stable reference voltage VCC_BAT to be connected to the power supply terminal VCC of the conversion control chip 141 according to the software control signal CTR3 and the hardware control signal SW_ON from the control module 20.

[0026] The conversion control chip 141 is an MCU chip of model UC3845G. The conversion control chip 141 includes a power supply terminal VCC, a ground terminal GND, an output terminal OUTPUT, and a feedback terminal VFB. The power supply terminal VCC is used to receive the drive voltage of the conversion control chip 141, the ground terminal VCC is used for grounding, the output terminal OUTPUT is used to output the control signal of the conversion drive switch 142, and the feedback terminal VFB is connected to the stable reference voltage VCC_BAT through a current limiting resistor. It is used to adjust the PWM pulse width of the control signal output by the output terminal OUTPUT based on the feedback of the stable reference voltage VCC_BAT.

[0027] The conversion control chip driver circuit 143 includes a chip driver switch 1431, a software driver optocoupler 1432, a hardware driver switch 1433, an external trigger button 1435, and a hardware driver optocoupler 1434. The input terminal of the chip driver switch 1431 is connected to the conversion power supply voltage BATIN, and its output terminal is connected to the power supply terminal VCC of the conversion control chip 141. The input terminal of the software driver optocoupler 1432 is connected to the control module 20, and its output terminal is connected to the control terminal of the chip driver switch 1431, providing the software control signal CTR3 output by the control module 20. The input terminal of the hardware driver switch 1433 is connected to the control terminal of the chip driver switch 1431, and its output terminal is connected to the negative terminal of the conversion power supply 15. Its control terminal receives the trigger signal from the external trigger button 1435. The external trigger button 1435 is used to issue the trigger signal from the hardware driver switch 1433 and the hardware control signal SW_ON. The hardware-driven optocoupler 1434 is used to send the hardware control signal SW_ON to the control module 20 to drive the software-driven optocoupler 1432.

[0028] The trigger signal here refers to the physical level change generated at both ends of the external trigger button 1435 after it is pressed, which is used to directly drive the hardware driver switch 1433 and the hardware driver optocoupler 1434. The hardware control signal SW_ON refers to the level signal output by the hardware driver optocoupler 1434 to the control module 20 after receiving the "trigger signal", which is used to notify the control module 20 that a hardware trigger event has occurred.

[0029] The conversion transformer 13 includes an input winding 131, an output winding 132, and a control winding 133. The input winding 131 is connected to the input unit 11 and the output control unit 14, respectively. The output winding 132 is connected to the output unit 12. The control winding 133 outputs a stable reference voltage VCC_BAT.

[0030] The control terminal of the conversion drive switch 142 is connected to the output terminal OUTPUT of the conversion control chip 141, the input terminal of the conversion drive switch 142 is connected to the input winding 131, and the output terminal of the conversion drive switch 142 is grounded. The power supply terminal VCC of the conversion control chip 141 is connected to the conversion power supply voltage BATIN and the stable reference voltage VCC_BAT through the conversion control chip drive circuit 143.

[0031] Specifically, in this embodiment, the chip-driven switch 1431 is a PNP transistor. The emitter of the chip-driven switch 1431 is connected to the conversion power supply voltage BATIN and the stable reference voltage VCC_BAT, respectively. The collector of the chip-driven switch 1431 is connected to the power supply terminal VCC of the conversion control chip 141. The positive terminal of the software-driven optocoupler 1432 is connected to the 5V power supply through a current-limiting resistor. The negative terminal of the software-driven optocoupler 1432 is connected to the software control signal CTR3 output by the control module 20. The emitter of the software-driven optocoupler 1432 is grounded, and the collector of the software-driven optocoupler 1432 is connected to the base of the chip-driven switch 1431.

[0032] The hardware driver switch 1433 is an NPN transistor. The collector of the hardware driver switch 1433 is connected to the control terminal of the chip driver switch 1431. The emitter of the hardware driver switch 1433 is grounded. The base of the hardware driver switch 1433 is connected to an external power supply (which includes the conversion power supply voltage BATIN and the stable reference voltage VCC_BAT) via an external trigger button 1435. The positive terminal of the hardware driver optocoupler 1434 is connected to an external power supply via an external trigger button 1435. The negative terminal of the hardware driver optocoupler 1434 is grounded. The emitter of the hardware driver optocoupler 1434 is connected to the control module 20. The collector of the hardware driver optocoupler 1434 is connected to a 5V power supply via a current-limiting resistor.

[0033] Furthermore, the conversion control chip drive circuit 143 also includes a conversion power switch 1436, which is an NPN transistor. The collector of the conversion power switch 1436 is connected to the conversion power supply voltage BATIN through a current-limiting resistor, the emitter of the conversion power switch 1436 is connected to the emitter of the chip drive switch 1431, and the base of the conversion power switch 1436 is connected to the conversion power supply voltage BATIN. At the same time, the base of the conversion power switch 1436 is also grounded through a Zener diode 1437, wherein the positive terminal of the Zener diode 1437 is grounded, and the negative terminal of the Zener diode 1437 is connected to the base of the conversion power switch 1436.

[0034] Furthermore, the conversion control chip drive circuit 143 also includes an energy storage capacitor 1438. One end of the energy storage capacitor 1438 is connected to the emitter of the chip drive switch 1431, and the other end of the energy storage capacitor 1438 is grounded. This energy storage capacitor can store energy for the output of the conversion power supply voltage BATIN and the stable reference voltage VCC_BAT, thereby improving the stability of the drive voltage of the conversion control chip 141.

[0035] The working principle of the dual-drive voltage conversion system in this embodiment is described in detail below.

[0036] When the dual-drive voltage conversion system is in software control mode, the control module receives a detection signal from the conversion power detection pin. If the detection signal determines that the conversion power supply voltage BATIN can supply power normally, it sends a software control signal CTR3 to the software drive optocoupler 1432. Under the control of the software control signal CTR3, the software drive optocoupler 1432 is turned on, thereby pulling down the potential of the control terminal of the chip drive switch 1431. The chip drive switch 1431 is then turned on, and the battery power supply voltage BATIN drives the conversion control chip 141 to start working through the chip drive switch 1431. Subsequently, the output terminal OUTPUT of the conversion control chip 141 outputs a PWM control signal to the control terminal of the conversion drive switch 142, and the conversion drive switch 142 is turned on. Under the control of the conversion drive switch 142, the input winding 131 is turned on, the conversion transformer 13 starts working, and the output winding 132 outputs the conversion voltage to the output unit 12. Then, the output unit 12 outputs a stable conversion power supply voltage SPSOUT to the DC bus.

[0037] Meanwhile, since the input winding 131 is in the conducting state, the control winding 133 also starts to work, and the control winding 133 outputs a stable reference voltage VCC_BAT to the output control unit 14; in this way, the conversion control chip 141 can work under the drive of the stable reference voltage VCC_BAT, ensuring the working stability of the subsequent conversion control chip 141.

[0038] If the control module 20 needs to cut off the output of the conversion power supply 15, the control module 20 only needs to stop outputting the software control signal CTR3 to the software driver optocoupler 1432. In this way, the output terminal of the software driver optocoupler 1432 stops outputting, the chip driver switch 1431 is turned off, the conversion control chip 141 stops working, the output terminal OUTPUT of the conversion control chip 141 stops outputting, the path of the input winding 131 is disconnected, the conversion transformer 13 stops working, and the conversion power supply 15 stops outputting.

[0039] When the dual-drive voltage conversion system is in hardware control mode, the user can send a trigger signal via the external trigger button 1435. The circuits on both sides of the external trigger button 1435 are turned on, and the hardware drive switch 1433 is turned on by the 15V switching power supply. This pulls the potential of the control terminal of the chip drive switch 1431 low, turning on the chip drive switch 1431. The conversion power supply BATIN then drives the conversion control chip 141 to start working through the chip drive switch 1431. The conversion transformer 13 starts working, and the output winding 132 outputs the conversion voltage to the output unit 12. Subsequently, the output unit 12 outputs a stable conversion supply voltage SPSOUT to the DC bus.

[0040] Simultaneously, since the input winding 131 is in the conducting state, the control winding 133 also starts to work, and the control winding 133 outputs a stable reference voltage VCC_BAT to the output control unit 14; at this time, the base of the hardware drive switch 1433 can also be connected to the stable reference voltage VCC_BAT through an external trigger button. In this way, the hardware drive switch 1433 can work under the drive of the stable reference voltage VCC_BAT, ensuring the working stability of the hardware drive switch 1433.

[0041] Simultaneously, the hardware-driven optocoupler 1434 is also turned on under the drive of the 15V switching power supply. The hardware-driven optocoupler 1434 generates a hardware control signal SW_ON and sends the hardware control signal SW_ON to the control module 20. Subsequently, the control module 20 outputs a software control signal CTR3. The software-driven optocoupler 1432 is turned on under the control of the software control signal CTR3, thereby simultaneously pulling down the potential of the control terminal of the chip-driven switching transistor 1431. The chip-driven switching transistor 1431 is turned on, and the conversion power supply voltage BATIN and the stable reference voltage VCC_BAT drive the conversion control chip 141 to start working through the chip-driven switching transistor 1431.

[0042] This design allows users to switch power supplies 15 directly by manually triggering the external trigger button 1435, bypassing the control module 20 and enabling rapid switching of power supplies 15. After switching power supplies 15, the continuous and stable operation of the power supply system requires comprehensive control from the control module 20, such as timely disconnection in case of subsequent abnormalities. Therefore, the hardware-driven optocoupler 1434 sends the switching signal to the control module 20 via the hardware control signal SW_ON. The control module 20 can then control the subsequent operating state of the power supplies 15 via the software control signal CTR3. Therefore, after the power supply 15 has finished switching, the external trigger button 1435 can be directly reset (for example, the control module 20 can control an analog switch or relay connected in parallel with the external trigger button 1435 through an additional GPIO port. After confirming that the software control signal CTR3 has been successfully established, it controls the analog switch or relay to disconnect, thereby achieving an 'electrical reset' of the external trigger button). The optocoupler 1432 is driven by software to control the conduction state of the chip drive switch 1431 and the working state of the conversion control chip 141. If the control module 20 receives the hardware control signal SW_ON but fails to send the software control signal CTR3 for various reasons (such as software setting problems), the control module 20 will not reset the external trigger button 1435 to ensure the current working state of the power supply 15.

[0043] In addition, the conversion control chip driver circuit also includes a conversion power switch transistor 1436. During the output of the conversion power supply voltage BATIN, if the conversion power supply voltage BATIN fluctuates, such as if the voltage of the conversion power supply voltage BATIN suddenly becomes too high, the conversion power switch transistor 1436 will automatically turn off to avoid the conversion power supply voltage BATIN damaging the chip driver switch transistor 1431. At the same time, the conversion power supply voltage BATIN can be discharged through the Zener diode 1437 to prevent the conversion power supply voltage BATIN from damaging the conversion power switch transistor 1436.

[0044] The above-mentioned software-driven optocoupler 1432 and hardware-driven switch 1433 provide dual control over the conduction state of the chip-driven switch 1431. This enables the power supply 15 to start quickly in manual mode, and also allows the control module 20 to maintain stable control after the power supply 15 starts up, thus ensuring the output stability of the switching power supply 15.

[0045] In this embodiment, the chip-driven switch 1431 is the main power control switch for the entire conversion control chip 141. Its input terminal is connected to the conversion power supply voltage BATIN and the stable reference voltage VCC_BAT, and its output terminal is connected to the power supply terminal VCC of the conversion control chip 141. It is responsible for determining whether to send the supply voltage to the conversion control chip 141, thereby controlling the start and stop of the entire voltage conversion system. The control terminal (base) of the chip-driven switch 1431 is simultaneously controlled by the software-driven optocoupler 1432 and the hardware-driven switch 1433. This design allows the switch to be turned on by pulling down the base potential, whether it is the software control signal CTR3 issued by the control module 20 or the trigger signal generated by the external trigger button 1435, thus realizing a "software and hardware combined" start-up mechanism.

[0046] The emitter of the chip-driven switching transistor 1431 is connected to both the conversion power supply voltage BATIN and the stable reference voltage VCC_BAT. During system startup, BATIN provides initial drive energy; once the conversion transformer 13 is operating normally, the control winding 133 generates a stable VCC_BAT to take over the power supply. This dual-source supply design ensures that the conversion control chip 141 receives a reliable drive voltage during both startup and steady-state operation, avoiding the risk of the chip shutting down due to fluctuations in a single power supply.

[0047] In this embodiment, the software-driven optocoupler 1432 serves as the electrical isolation interface between the control module 20 and the power stage circuit. Its input terminal (LED side) receives the software control signal CTR3 output from the control module 20, and its output terminal (phototransistor side) connects to the control terminal of the chip-driven switch 1431, used to transmit the turn-on command from the software side. Internally, the optocoupler transmits optical signals, achieving complete electrical isolation between the low-voltage side of the control module 20 and the high-voltage power side (the conversion power supply voltage can reach tens of volts). This effectively prevents high-voltage surges and spike noise from the power side from back-entering the control module 20, protecting sensitive devices such as the MCU and improving the overall system's anti-interference capability and safety. The software control signal CTR3 output by the control module 20 is typically a logic level of 3.3V or 5V, while the base control of the chip-driven switch 1431 needs to be pulled down to near 0V for reliable conduction. The software-driven optocoupler 1432 reduces the collector-emitter voltage to the saturation voltage drop (approximately 0.2-0.3V) when turned on, achieving level adaptation conversion from low-voltage logic signals to power stage pull-down drives.

[0048] In this embodiment, the hardware-driven switch 1433 constitutes an independent startup path completely independent of the control module 20. When the control module 20 is unable to issue the software control signal CTR3 due to a system crash, program malfunction, initialization failure, or communication interruption, the operator can still press the external trigger button 1435 to apply 15V switching power to the base of the hardware-driven switch 1433, turning it on and thus forcibly starting the voltage conversion system. This design has extremely high practical value in equipment debugging, fault recovery, and emergency power supply scenarios. Its conduction behavior is not constrained by the software state of the control module 20. As long as the base receives sufficient drive voltage, the control terminal potential can be forcibly pulled low, turning on the chip-driven switch 1431. This design gives the hardware trigger signal absolute priority (when the hardware drive switch 1433 is turned on, it pulls the control terminal potential of the chip drive switch 1431 to near the negative terminal, so that the software drive optocoupler 1432 does not change the control terminal potential of the chip drive switch 1431 regardless of whether it is turned on or off), ensuring that manual intervention can be effective under any circumstances.

[0049] In this embodiment, the hardware-driven optocoupler 1434 feeds back the "hardware control signal SW_ON" to the control module 20 when a hardware trigger occurs, notifying the control module 20 that someone has performed a hardware operation. Upon receiving the hardware control signal SW_ON, the control module 20 immediately responds in its interrupt service routine, synchronously outputting the software control signal CTR3. This allows the software-driven optocoupler 1432 and the hardware-driven switch 1433 to simultaneously act on the control terminal of the chip-driven switch 1431, forming a "double-insurance" drive. Subsequently, the control module 20 can reset the external trigger button 1435 (via software-controlled relays or analog switches), smoothly transferring continuous control of the system from the hardware path to the software path, achieving a seamless transition from "manual emergency start" to "software intelligent maintenance." If the control module 20 fails to issue the software control signal CTR3 normally after receiving the hardware control signal SW_ON due to software configuration errors, resource conflicts, or logical defects, the control module 20 will not execute the reset operation of the external trigger button 1435. At this time, the hardware-driven switch 1433 will remain on, and the system will continue to operate in hardware self-locking mode, avoiding the risk of unexpected power failure due to software failure. This fault-tolerant design significantly improves the reliability of the system.

[0050] In this embodiment, the switching power supply transistor 1436 is an NPN transistor. It works in conjunction with the Zener diode 1437 to form an overvoltage protection circuit for the switching power supply voltage BATIN. Its core function is to provide a stable power supply path for the switching control chip 141 when the switching power supply voltage BATIN is normal, and to automatically cut off the power supply and protect the subsequent circuit when the switching power supply voltage BATIN rises abnormally.

[0051] When the switching power supply voltage BATIN is within its rated range (e.g., 12V-15V), the Zener diode 1437 is not broken down and is in the off state. At this time, the base of the switching power supply transistor 1436 is connected to BATIN through a resistor, and its collector is also connected to the switching power supply voltage BATIN (through a current-limiting resistor). Because the base and emitter potentials are close, the switching power supply transistor 1436 is in a slightly conducting or critically conducting state. This design results in low impedance during normal operation, allowing the current corresponding to the switching power supply voltage BATIN to flow smoothly through 1436 to the emitter of the chip driver switch 1431, thereby powering the switching control chip 141. The current-limiting resistor limits the base current, ensuring that the switching power supply transistor 1436 operates within a safe operating range.

[0052] When the switching power supply voltage BATIN rises abnormally (such as due to power surge, load change, lightning strike, etc.) to exceed the breakdown voltage of the Zener diode 1437 (e.g., set to 18V), the Zener diode 1437 reverse-biasedly breaks down and conducts, clamping the base voltage of the switching power supply transistor 1436 to the breakdown voltage level (approximately 18V). At this time, the base voltage of the switching power supply transistor 1436 no longer rises with the switching power supply voltage BATIN, but is fixed at 18V. As the switching power supply voltage BATIN continues to rise (e.g., to 20V), the emitter voltage also rises to close to 20V. At this time, the base voltage (18V) is lower than the emitter voltage (20V), and the conduction condition of the switching power supply transistor 1436 is no longer met. The switching power supply transistor 1436 quickly switches from the on state to the off state. After the switching power supply transistor 1436 is turned off, the power supply path from the switching power supply voltage BATIN to the emitter of the chip driver switch transistor 1431 through the switching power supply transistor 1436 is cut off. Even if the chip driver switch 1431 is turned on under control, its emitter cannot obtain current from the conversion power supply voltage BATIN, thereby indirectly preventing the conversion control chip 141 from obtaining the drive voltage and realizing system-level overvoltage protection shutdown.

[0053] The dual-drive voltage conversion system provided by this invention can issue software control signals through the control module and hardware control signals through an external trigger button. The hardware control signals have a higher priority than the software control signals, so users do not need to redesign the software control signals for special scenarios. Users can easily switch between software and hardware control simply by using the hardware control signals. This effectively solves the technical problems of high software design complexity and complicated operation process for switching between software and hardware control in existing voltage conversion systems.

[0054] In summary, although the present invention has been disclosed above with reference to preferred embodiments, the above preferred embodiments are not intended to limit the present invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the scope defined in the claims.

Claims

1. A dual-drive voltage conversion system, characterized in that, Includes voltage conversion circuitry and control module; The voltage conversion circuit mentioned above includes: The input unit is used to connect to the conversion power supply; The output unit is used to output a stable converted power supply voltage to the DC bus; An output control unit is configured to control the on / off state of the input unit based on the conversion drive signal from the control module; and The conversion transformer is connected to the input unit, output unit, and output control unit respectively, and is used to convert the power supply voltage. The output control unit includes: The conversion control chip is used to generate control signals for driving the conversion switching transistor; A conversion drive switch, connected to the conversion transformer, is used to start the conversion transformer based on the control signal; and A conversion control chip driving circuit is used to generate the driving voltage of the conversion control chip; The conversion control chip drive circuit includes: The chip drives the switching transistor, whose input terminal is connected to the conversion power supply, and whose output terminal is connected to the power supply terminal of the conversion control chip. A software-driven optocoupler has its input end connected to the control module and its output end connected to the control end of the chip-driven switching transistor, and is used to provide the software control signal output by the control module. The hardware-driven switching transistor has its input terminal connected to the control terminal of the chip-driven switching transistor, its output terminal connected to the negative terminal of the conversion power supply, and its control terminal receiving hardware control signals. When the hardware-driven switching transistor is turned on, it forcibly pulls the potential of the control terminal of the chip-driven switching transistor to close to the negative terminal potential, so that the software-driven optocoupler does not change the potential of the control terminal regardless of whether it is turned on or off. An external trigger button is used to send the hardware control signal; and A hardware-driven optocoupler is used to send the hardware control signals to the control module; The control module outputs the software control signal in response to receiving the hardware control signal; the control module performs the reset operation of the external trigger button only after confirming that the software control signal is effective, otherwise it maintains the trigger state of the external trigger button to keep the hardware drive path open.

2. The dual-drive voltage conversion system according to claim 1, characterized in that, The input unit is provided with a conversion power detection pin that is connected to the control module; When the dual-drive voltage conversion system is in software control mode, the control module determines to send a software control signal to the software drive optocoupler through the detection signal of the conversion power detection pin, drives the chip drive switch to turn on, and then drives the conversion control chip and the conversion transformer to work normally. When the dual-drive voltage conversion system is driven by the external trigger button, the external trigger button sends a trigger signal to drive the hardware drive switch and the chip drive switch to turn on, thereby driving the conversion control chip and the conversion transformer to work normally.

3. The dual-drive voltage conversion system according to claim 2, characterized in that, When the dual-drive voltage conversion system is driven by the external trigger button, the external trigger button sends a trigger signal, which drives the hardware drive optocoupler to send the hardware control signal to the control module. The control module synchronously sends the software control signal based on the hardware control signal, and the software control signal is used to drive the chip drive switch to turn on.

4. The dual-drive voltage conversion system according to claim 3, characterized in that, If the control module synchronously sends the software control signal based on the hardware control signal, the external trigger button will be reset; if the control module receives the hardware control signal but does not send the software control signal, the external trigger button will not be operated.

5. The dual-drive voltage conversion system according to claim 1, characterized in that, The conversion transformer includes an input winding, an output winding, and a control winding. The input winding is connected to the input unit and the output control unit, respectively. The output winding is connected to the output unit. The control winding outputs a stable reference voltage. The control terminal of the conversion drive switch is connected to the output terminal of the conversion control chip, the input terminal of the conversion drive switch is connected to the input winding, and the output terminal of the conversion drive switch is grounded. The power supply terminal of the conversion control chip is connected to the conversion power supply and the stable reference voltage respectively through the conversion control chip drive circuit.

6. The dual-drive voltage conversion system according to claim 5, characterized in that, The chip driver switch is a PNP transistor. The emitter of the chip driver switch is connected to the conversion power supply and the stable reference voltage, respectively. The collector of the chip driver switch is connected to the power supply terminal of the conversion control chip. The positive terminal of the software-driven optocoupler is connected to a 5V power supply through a current-limiting resistor, the negative terminal of the software-driven optocoupler is connected to the software control signal output by the control module, the emitter of the software-driven optocoupler is grounded, and the collector of the software-driven optocoupler is connected to the base of the chip-driven switch. The hardware driving switch is an NPN transistor. The collector of the hardware driving switch is connected to the control terminal of the chip driving switch. The emitter of the hardware driving switch is grounded. The base of the hardware driving switch is connected to an external power supply through the external trigger button. The positive terminal of the hardware driver optocoupler is connected to an external power supply through the external trigger button, the negative terminal of the hardware driver optocoupler is grounded, the emitter of the hardware driver optocoupler is connected to the control module, and the collector of the hardware driver optocoupler is connected to a 5V power supply through a current-limiting resistor.

7. The dual-drive voltage conversion system according to claim 6, characterized in that, The base of the hardware-driven switching transistor is also connected to the conversion power supply and the stable reference voltage via the external trigger button.

8. The dual-drive voltage conversion system according to claim 6, characterized in that, The conversion control chip also includes a feedback terminal, which is connected to the stable reference voltage through a current-limiting resistor.

9. The dual-drive voltage conversion system according to claim 6, characterized in that, The conversion control chip driving circuit also includes a conversion power switch transistor, which is a PNP transistor. The collector of the conversion power switch transistor is connected to the conversion power supply through a current-limiting resistor. The emitter of the conversion power switch transistor is connected to the emitter of the chip driving switch transistor. The base of the conversion power switch transistor is connected to the conversion power supply. At the same time, the base of the conversion power switch transistor is also grounded through a Zener diode, wherein the anode of the Zener diode is grounded and the cathode of the Zener diode is connected to the base of the conversion power switch transistor.

10. The dual-drive voltage conversion system according to claim 6, characterized in that, The conversion control chip driving circuit also includes an energy storage capacitor, one end of which is connected to the emitter of the chip driving switch, and the other end of which is grounded.

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