Logic circuit and method for improving power conversion product power-up and power-down operation stability

Abstract

The application discloses a logic circuit and method for improving power conversion product up and down power operation stability, which comprises an up power shielding protection circuit, a de-bounce processing circuit, a protection logic execution circuit, a down power self-help discharge circuit and a protection execution device; the up power shielding protection circuit is used for shielding a false protection signal in a product up power process; the de-bounce processing circuit is used for shielding voltage noise and burr in a starting up power and normal protection logic process; the protection logic execution circuit is used for generating a signal for executing protection logic; the down power self-help discharge circuit is used for timely discharging charges stored in a capacitor of the up power shielding protection circuit in a product down power process; and the protection execution device is used for executing a logic protection action. The application can effectively solve product working stability and fault tolerance problems.

Description

Technical Field

[0001] This invention belongs to the field of aviation power conversion control, specifically relating to a logic circuit and method for improving the stability of power conversion products during frequent power-on and power-off operations. Background Technology

[0002] With the rapid development of power electronics technology, aviation power systems have gradually entered the era of multi-electric and all-electric systems. As the core technology of multi-electric aircraft, multi-electric systems, compared to traditional systems, utilize electrical energy for control and distribution in their secondary power systems. Secondary power supplies, acting as the link between the power generation system and the load, are fundamental to multi-electric systems and multi-electric aircraft; their performance directly affects the reliability of the entire airborne power generation system. Considering the operating environment and conditions of airborne power generation systems, current research focus on secondary power supply devices mainly concentrates on high reliability, high efficiency, high power, small size, and fast dynamic response.

[0003] However, existing high-power converter products, during installation and use, suffer from low reliability and poor fault tolerance due to the complex electromagnetic environment and stringent dynamic response requirements on board. Inadequate design of the converter's control and protection circuits can negatively impact aircraft safety and operational missions. Therefore, improving and refining the design of control and protection circuits is a crucial and effective measure to ensure the fault tolerance and reliability of installed power converter products. Summary of the Invention

[0004] The technical problem to be solved:

[0005] To overcome the shortcomings of existing technologies, and addressing the poor fault tolerance of current control and protection circuits in aviation power conversion products, this invention provides a logic circuit that can improve the stability of aviation power conversion products during frequent power-on processes, effectively solving the problems of product operational stability and fault tolerance. In the following technical solution, "Fault" is a fault protection signal, which can be a product overvoltage, undervoltage, overcurrent, or other fault protection signal. It is low-level during fault protection and high-level during normal product operation.

[0006] The technical solution of the present invention is: a logic circuit for improving the stability of power conversion products during frequent power-on and power-off operations, characterized in that: it includes a power-on shielding protection circuit, a debouncing processing circuit, a protection logic execution circuit, a power-off self-discharge circuit, and a protection execution device; the fault protection signal passes through the power-on shielding protection circuit, the debouncing processing circuit, and the protection logic execution circuit to reach the protection execution device, and the power-off self-discharge circuit is connected in parallel with the power shielding protection circuit;

[0007] The power-on shielding protection circuit is used to shield false protection signals during the product's power-on process. After the product's power-on startup is completed, this part of the circuit loses its shielding protection function. When a normal protection signal is triggered, it does not affect the product's normal protection logic.

[0008] The debouncing circuit is used to shield voltage noise and glitches during startup and normal protection logic processes.

[0009] The protection logic execution circuit is used to generate signals for executing protection logic;

[0010] The power-off self-discharge circuit is used to discharge the charge stored in the capacitor of the power-on shielding protection circuit in a timely manner during the power-off process of the product, so as to ensure that the product can start stably and reliably next time and meet the requirements of frequent start-stop on the machine.

[0011] The protection execution device is used to perform logical protection actions.

[0012] A further technical solution of the present invention is as follows: The power-on shielding protection circuit includes a capacitor C4, a resistor R8, and a transistor VT1 connected in sequence. The working principle is as follows: Utilizing the capacitor's "AC-passing and DC-blocking" characteristics and charging characteristics, during the product's power-on process, VCC charges the capacitor C4. The capacitor charging current causes point b of the transistor VT1 to open, and points c and e of VT1 to connect. At this time, the false protection signal is shielded, solving the power-on false protection problem of the power conversion product. After the product is powered on, the capacitor C4 is fully charged, VCC is not powered off, and the capacitor C4 remains fully charged, thus the shielding protection function is ineffective. When the product receives a normal protection signal, the product executes the protection logic normally.

[0013] A further technical solution of the present invention is as follows: the debouncing processing circuit includes a resistor R2, a Zener diode VD1, a diode VD3, a resistor R7, and a capacitor C3; the resistor R2 serves as a current limiting protection; the Zener diode VD1 utilizes the characteristics of a Zener diode, and only works normally when the voltage is higher than the forward voltage of VD1, and does not work when the voltage is lower than the forward voltage of VD1; the voltage ripple and noise below the forward voltage of VD1 are filtered out, thereby achieving the effect of debouncing and noise reduction.

[0014] A further technical solution of the present invention is: in the debouncing processing circuit, resistor R2, Zener diode VD1, and capacitor C3 are connected in sequence, and diode VD3 and resistor R7 are connected in series and then connected in parallel with capacitor C3.

[0015] A further technical solution of the present invention is as follows: the protection logic execution circuit includes a resistor R1, a capacitor C1, a thyristor VD2, a resistor R6, a resistor R3, and a transistor VT2; the signals in the circuit are filtered through R1 and C1; when the Fault signal in the circuit is at a low fault level, point G of VD2 will be at a high level, points A and K of VD2 will be turned on, the PWMOFF signal will be at a high level, VT2 will be turned on, and the protection execution signal OUT_Protection will be pulled low and sent to the protection execution mechanism.

[0016] A further technical solution of the present invention is as follows: In the protection logic execution circuit, resistor R1, thyristor VD2, resistor R3, and transistor VT2 are connected in sequence; the positive terminal of capacitor C1 is connected between resistor R1 and thyristor VD2, and the negative terminal is grounded; resistor R6 is connected in parallel with resistor R3 and transistor VT2.

[0017] A further technical solution of the present invention is: the power-off self-discharge circuit includes a resistor R9 and a diode VD4; during the product power-on process, VD4 does not work and does not affect the normal power-on operation of the product; after the product is powered off, the charge of capacitor C4 forms a discharge circuit through resistor R9, ground and diode VD4, which can quickly discharge and ensure that the shielding abnormal protection function can work normally when restarting quickly again.

[0018] A further technical solution of the present invention is: the resistor R9 and the diode VD4 are connected in series and then connected in parallel with the capacitor C4, and the connection terminals of the resistor R9 and the diode VD4 are grounded.

[0019] A further technical solution of the present invention is that the fault protection signal is a logic level of 15V high or 0V low.

[0020] When the Fault signal is high at 15V, it indicates that the product is working normally. VT1 is turned on, the collector of VT1 is grounded, the debouncing circuit does not work, the PWMOFF signal in the protection execution circuit is low at 0V, the protection logic execution circuit does not generate a protection signal, and OUT_Protection is high.

[0021] When the Fault signal is high at 0V, it indicates a product malfunction. VT1 is turned off, VT1 is open, the debouncing circuit is activated, the PWMOFF signal in the protection execution circuit is 6V high, the protection logic execution circuit generates a protection signal, and OUT_Protection is 0V low.

[0022] A method for implementing a logic circuit to improve the stability of power conversion products during frequent power-on and power-off operations, characterized by the following specific steps:

[0023] Step 1: During the product power-on process, if there is a short-term overshoot, glitches or ripple in the product output voltage and current, a short-term fault signal will appear. This is not the normal operating logic of the system, and the fault needs to be masked.

[0024] Step 2: Power-on shielding circuit. During the product power-on process, VCC charges capacitor C4. The capacitor charging current turns on transistor VT1:b, and VT1:c and VT1:e are connected. In the protection execution circuit, the PWMOFF signal is 0V low level, the protection logic execution circuit does not generate a protection signal, and OUT_Protection is high level, thus achieving the function of power-on shielding protection.

[0025] Step 3: After the product is powered on, all indicators are output normally, the Fault signal is high level 15V, capacitor C4 is fully charged, VCC is not powered off, capacitor C4 is always fully charged, the shielding protection function is ineffective, when the product receives a normal protection signal, the product can execute the protection logic normally.

[0026] Step 4: During normal operation of the product, VT1:c and VT1:e are connected. If there is an interference signal or ripple in the ground loop, and the amplitude of the interference signal does not reach the conduction voltage of VD1, the protection logic execution circuit will not generate a protection signal, thus the circuit plays the role of debouncing and filtering.

[0027] Step 5: During the power-down process, the charge of capacitor C4 is discharged quickly through resistor R9, ground and diode VD4 to form a discharge circuit. When the product is restarted quickly, the charge of capacitor C4 is guaranteed to be 0, ensuring that the power-on shielding protection circuit function normally during short-term rapid restart.

[0028] There are no specific requirements or regulations regarding the resistance, capacitance, and component models in each circuit; they can be configured according to actual use.

[0029] Beneficial effects

[0030] The beneficial effects of this invention are as follows:

[0031] (1) In this invention, the power-on shielding abnormal protection function utilizes the capacitor charging characteristics of electronic components to complete a specific function. The circuit implementation logic and method are relatively simple, requiring no additional active logic circuits, and the circuit can operate stably and reliably.

[0032] (2) In this invention, the debouncing circuit utilizes the conduction characteristics of the Zener diode to shield voltage noise within a certain range in the circuit, thereby achieving signal debouncing. The circuit implementation logic and method are relatively simple, requiring no additional active logic circuitry, and the circuit operates stably and reliably.

[0033] (3) In this invention, the power-down self-discharge circuit is combined with the working process of the power-on shielding abnormal protection function logic circuit. In the power-on shielding protection function circuit, resistors and diodes are added to provide a discharge circuit for the capacitor after power-down. The circuit implementation logic and method are relatively simple, without the need to add additional active logic circuits, so that the capacitor charge of the product shielding power-on abnormal protection is quickly discharged, ensuring that the shielding protection function works normally in two adjacent fast start-up cycles, and improving the product's reliability and fault tolerance.

[0034] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0035] Figure 1 This is a block diagram of a logic circuit for improving the stability of power conversion products during frequent power-on and power-off operations according to the present invention.

[0036] Figure 2 This is a schematic diagram of a logic circuit for improving the stability of power conversion products during frequent power-on and power-off operations, according to the present invention. Detailed Implementation

[0037] The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.

[0038] This embodiment presents a logic circuit that can be used to improve the stability of aviation power conversion products during frequent power-on processes. The principle block diagram is as follows: Figure 1 As shown, it specifically includes:

[0039] Power-on shielding protection circuit: For power conversion products, there may be some voltage spikes or surges during startup. These signals are weak or false alarms and will not harm the product or load. However, if this signal is used as a judgment condition for the control and protection logic, it will cause the product to trigger false protection. This part of the circuit is used to shield the false protection signal during the product's power-on process. After the product's power-on startup is completed, this part of the circuit loses its shielding protection function. When a normal protection signal is triggered, it will not affect the product's normal protection logic.

[0040] Debouncing circuit: This part of the circuit is used to shield voltage noise and glitches during startup and normal protection logic processes.

[0041] Protection logic execution circuit: This part of the circuit is used to generate signals for executing protection logic.

[0042] Power-off self-discharge circuit: This circuit is used to promptly discharge the charge stored in the capacitor of the power-on shielding protection circuit during the power-off process, ensuring that the product can start stably and reliably next time, and meeting the requirements of frequent start-stop operation.

[0043] Protection actuator: This part of the circuit is used to perform logic protection actions.

[0044] Detailed circuit diagram as follows Figure 2 As shown, the circuits are described in detail below:

[0045] (1) Power-on shielding protection circuit

[0046] The power-on shielding protection circuit consists of capacitor C4, resistor R8, and transistor VT1. The "Fault" signal is a fault protection signal that can detect overvoltage, undervoltage, overcurrent, and other faults. It is low during fault protection and high during normal operation. Its working principle utilizes the capacitor's "AC-passing, DC-blocking" and charging characteristics. During power-on, VCC charges capacitor C4, and the charging current turns on transistor VT1:b, connecting VT1:c and VT1:e. This shields the false protection signal, resolving the power-on false protection issue in power conversion products. After power-on, capacitor C4 is fully charged, VCC remains powered, and capacitor C4 remains fully charged, rendering the shielding protection function ineffective. When the product receives a normal protection signal, it can execute the protection logic normally.

[0047] (2) Debounce processing circuit

[0048] The debouncing circuit consists of resistor R2, Zener diode VD1, diode VD3, resistor R7, and capacitor C3. Resistor R2 provides current limiting protection. Zener diode VD1 utilizes its Zener diode characteristics; it only operates normally when the voltage is above its forward voltage and not when the voltage is below its forward voltage. This filters out voltage ripple and noise below the forward voltage of VD1, thus achieving debouncing and noise reduction.

[0049] (3) Protect the logic execution circuit

[0050] The protection logic execution circuit consists of resistor R1, capacitor C1, thyristor VD2, resistor R6, resistor R3, and transistor VT2. R1 and C1 filter the signals in the circuit. When the Fault signal in the circuit is at a low level, VD2:G will be high, VD2:A and VD2:K will be turned on, the PWMOFF signal will be high, VT2 will be turned on, and the protection execution signal OUT_Protection will be pulled low and sent to the protection execution mechanism.

[0051] (4) Power-off self-discharge circuit

[0052] The self-discharge circuit after power-off consists of resistor R9 and diode VD4. During product power-on, VD4 is not working and does not affect the normal power-on operation of the product. After the product is powered off, the charge of capacitor C4 is discharged quickly through resistor R9, ground, and diode VD4 to form a discharge circuit, ensuring that the shielding abnormal protection function can be used normally for rapid restart.

[0053] (5) The Fault signal can be a fault protection signal such as overvoltage, undervoltage, or overcurrent. This signal is a logic level of either 15V high or 0V low. When the Fault signal is 15V high, it indicates that the product is working normally. VT1 is on, VT1:C terminal is grounded, the debouncing circuit is not working, the PWMOFF signal in the protection execution circuit is 0V low, the protection logic execution circuit does not generate a protection signal, and OUT_Protection is high. When the Fault signal is 0V high, it indicates that the product is malfunctioning. VT1 is off, VT1 is open, the debouncing circuit is working, the PWMOFF signal in the protection execution circuit is 6V high, the protection logic execution circuit generates a protection signal, and OUT_Protection is 0V low.

[0054] The entire circuit implementation steps are as follows:

[0055] Step 1: During the product startup and power-on process, the Fault signal has an abnormally low level. When the product starts up and powers on, VCC charges capacitor C4. The capacitor charging current turns on transistor VT1:b, and VT1:c and VT1:e are connected. At this time, the false protection signal will be shielded. In the protection execution circuit, the PWMOFF signal is 0V low level, the protection logic execution circuit does not generate a protection signal, and OUT_Protection is high level, thus achieving the function of shielding power-on protection.

[0056] Step 2: After the product is powered on, all indicators are output normally, the Fault signal is high level 15V, capacitor C4 is fully charged, VCC is not powered, capacitor C4 is always fully charged, the shielding protection function is ineffective, when the product receives a normal protection signal, the product can execute the protection logic normally.

[0057] Step 3: During the stable operation of the product, the characteristics of the Zener diode VD1 are utilized. VD1 will only work normally when the voltage is higher than the forward voltage of VD1, and VD1 will not work when the voltage is lower than the forward voltage of VD1. This will prevent the protection and execution circuit from working, thereby playing a role in debouncing and noise reduction, and improving the stability and fault tolerance of the product.

[0058] Step 4: After the product is powered off, the charge of capacitor C4 is discharged quickly through resistor R9, ground and diode VD4 to form a discharge circuit. When the product is restarted quickly again, the charge of capacitor C4 is guaranteed to be 0, ensuring that the power-on shielding protection circuit function normally when the product is restarted quickly for a short time.

[0059] There are no specific requirements or regulations regarding the resistance, capacitance, and component models in each circuit; they can be configured according to actual use.

[0060] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention.

Claims

1. A logic circuit for improving the stability of power conversion products during frequent power-on and power-off operations, characterized in that: It includes a power-on shielding protection circuit, a debouncing processing circuit, a protection logic execution circuit, a power-off self-discharge circuit, and a protection execution device; the fault protection signal passes through the power-on shielding protection circuit, the debouncing processing circuit, and the protection logic execution circuit to reach the protection execution device, and the power-off self-discharge circuit is connected in parallel to the power-on shielding protection circuit; The power-on shielding protection circuit is used to shield the false fault protection signal during the product power-on process. After the product power-on start-up is completed, the power-on shielding protection circuit loses its shielding protection function. When a normal fault protection signal is triggered, it does not affect the normal protection logic of the product. The debouncing circuit is used to shield voltage noise and glitches during power-on startup and normal protection logic processes. The protection logic execution circuit is used to generate signals for executing protection logic; The power-off self-discharge circuit is used to discharge the charge stored in the capacitor of the power-on shielding protection circuit in a timely manner during the power-off process of the product, so as to ensure that the product can be stably and reliably powered on and started next time, and can meet the requirements of frequent start-stop on the machine. The protection execution device is used to perform logical protection actions; The power-on shielding protection circuit includes a capacitor C4, a resistor R8, and a transistor VT1 connected in sequence. One end of the capacitor C4 is connected to the power supply VCC, and the other end of the capacitor C4 is connected to the base of the transistor VT1 through the resistor R8. The collector of the transistor VT1 is connected to the debouncing circuit. The fault protection signal is input to the base of the transistor VT1, and the emitter of the transistor VT1 is connected to ground. The debouncing circuit includes a resistor R2, a Zener diode VD1, a diode VD3, a resistor R7, and a capacitor C3. One end of the resistor R2 is connected to the power supply VCC, and the other end of the resistor R2 is connected to the collector of the transistor VT1 and the cathode of the Zener diode VD1. The anode of the Zener diode VD1 is connected to one end of the capacitor C3 and the anode of the diode VD3. The cathode of the diode VD3 is connected to one end of the resistor R7 and the protection logic execution circuit. The other ends of the capacitor C3 and the other ends of the resistor R7 are both connected to ground. The protection logic execution circuit includes a resistor R1, a capacitor C1, a thyristor VD2, a resistor R6, a resistor R3, and a transistor VT2. One end of the resistor R1 is connected to the power supply VCC, and the other end of the resistor R1 is connected to one end of the capacitor C1 and the anode of the thyristor VD2. The other end of the capacitor C1 is connected to ground. The gate of the thyristor VD2 is connected to the cathode of the diode VD3. The cathode of the thyristor VD2 is connected to one end of the resistor R6 and one end of the resistor R3. The cathode of the thyristor VD2 outputs a PWMOFF signal. The other end of the resistor R6 is connected to ground. The other end of the resistor R3 is connected to the base of the transistor VT2. The emitter of the transistor VT2 is connected to ground. The collector of the transistor VT2 outputs a protection execution signal OUT_Protection to the protection execution device. The power-down self-discharge circuit includes a resistor R9 and a diode VD4; one end of the resistor R9 is connected to one end of the capacitor C4, the cathode of the diode VD4 is connected to the other end of the capacitor C4, and the other ends of the resistor R9 and the diode VD4 are both connected to ground.

2. The logic circuit for improving the stability of power conversion products during frequent power-on and power-off operations according to claim 1, characterized in that: The power-on shielding protection circuit works by utilizing the capacitor's "AC-passing, DC-blocking" and charging characteristics. During the product's startup and power-on process, the power supply VCC charges capacitor C4, and the capacitor's charging current turns on transistor VT1, connecting its collector and emitter. At this time, the false fault protection signal is shielded, resolving the power-on false protection problem of the power conversion product. After the product is powered on, capacitor C4 is fully charged, and the power supply VCC is not interrupted. Capacitor C4 remains fully charged, and the shielding protection function is disabled. When the product receives a normal fault protection signal, the product executes the protection logic normally.

3. The logic circuit for improving the stability of power conversion products during frequent power-on and power-off operations as described in claim 1, characterized in that: Resistor R2 serves as a current limiting protection. Zener diode VD1 utilizes the characteristics of a Zener diode; it will only work normally when the voltage is higher than its turn-on voltage and will not work when the voltage is lower than its turn-on voltage. This filters out voltage ripple and noise below the turn-on voltage of Zener diode VD1, thus achieving the function of de-jittering and noise reduction.

4. The logic circuit for improving the stability of power conversion products during frequent power-on and power-off operations according to claim 1, characterized in that: The signal in the circuit is filtered by resistor R1 and capacitor C1. When the fault protection signal in the circuit is low, the gate of thyristor VD2 will be high, the anode and cathode of thyristor VD2 will be turned on, the PWMOFF signal will be high, the transistor VT2 will be turned on, and the protection execution signal OUT_Protection will be pulled low and sent to the protection execution device.

5. The logic circuit for improving the stability of power conversion products during frequent power-on and power-off operations according to claim 1, characterized in that: During product power-on, diode VD4 does not work and does not affect the normal power-on operation of the product; after the product is powered off, the charge of capacitor C4 is discharged quickly through resistor R9, ground and diode VD4 to form a discharge circuit, ensuring that the shielding abnormal protection function can work normally when the product is quickly powered on again.

6. A logic circuit for improving the stability of power conversion products during frequent power-on and power-off operations according to any one of claims 1-5, characterized in that: The fault protection signal is a logic level of either 15V high or 0V low. When the Fault signal is high at 15V, it indicates that the product is working normally. Transistor VT1 is turned on, the collector of transistor VT1 is connected to ground, the debouncing circuit does not work, the PWMOFF signal in the protection logic execution circuit is low at 0V, the protection logic execution circuit does not generate a protection execution signal, and OUT_Protection is high. When the Fault signal is low (0V), it indicates a product malfunction. Transistor VT1 is turned off, VT1 is open-circuited, the debouncing circuit is activated, the PWMOFF signal in the protection logic execution circuit is high (6V), the protection logic execution circuit generates a protection execution signal, and OUT_Protection is low (0V).

7. A method for implementing the logic circuit described in any one of claims 1-6 for improving the stability of power conversion products during frequent power-on and power-off operations, characterized in that: The specific steps are as follows: Step 1: During the product power-on process, if there is a short-term overshoot, glitches or ripple in the product output voltage and current, a short-term fault signal will appear in the Fault signal. This is not the normal operating logic of the system, and the short-term fault signal needs to be shielded. Step 2: Power-on shielding protection circuit. During the power-on process of the product, the power supply VCC charges the capacitor C4. The charging current of the capacitor turns on the transistor VT1. The collector-emitter junction of the transistor VT1 is connected. The PWMOFF signal in the protection logic execution circuit is 0V low level. The protection logic execution circuit does not generate a protection execution signal. OUT_Protection is high level, thus achieving the function of shielding power-on protection. Step 3: After the product is powered on, all indicators are output normally, the Fault signal is high level 15V, capacitor C4 is fully charged, the power supply VCC is not interrupted, capacitor C4 is always fully charged, the shielding protection function is ineffective, when the product receives a normal protection signal, the product can execute the protection logic normally. Step 4: During normal operation of the product, the collector-emitter junction of transistor VT1 is connected. If there is an interference signal or ripple in the ground circuit, and the amplitude of the interference signal or ripple does not reach the conduction voltage of Zener diode VD1, the protection logic execution circuit will not generate a protection execution signal, so the debouncing processing circuit plays the role of debouncing and filtering. Step 5: During the power-down process, the charge of capacitor C4 is discharged quickly through resistor R9, ground and diode VD4 to form a discharge circuit. When the product is quickly powered on again, the charge of capacitor C4 is guaranteed to be 0, ensuring that the power-on shielding protection circuit function normally when the product is quickly powered on again.

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