Multi-path direct-current power supply redundancy control circuit based on dynamic sampling resistance adjustment

Abstract

The invention relates to the technical field of power electronics, in particular to a multipath direct-current power supply redundancy control circuit based on dynamic sampling resistance adjustment. Comprising three redundant circuits and a support capacitor, the three redundant circuits are output in parallel, one end of the support capacitor is connected with the output end of the parallel output of the redundant circuits, and the other end of the support capacitor is grounded; an adjustable sampling resistor network is adopted to monitor the voltage of each path in real time and dynamically adjust the voltage, so that accurate control is realized; in combination with MOSFET and operational amplifier control, output voltage fluctuation is reduced during power supply fault switching, and influence on operation of load equipment is avoided; compared with a software scheme, hardware closed-loop control is faster in response, and seamless switching is ensured.

Description

Technical Field

[0001] This invention relates to the field of power electronics technology, and more specifically to a multi-channel DC power supply redundancy control circuit based on dynamic sampling resistor adjustment. Background Technology

[0002] High-reliability DC power supply systems are crucial in modern industrial control, communication equipment, data centers, and medical electronics. Traditional redundant power supply designs typically employ mechanical relay switches or MOSFET isolation schemes, but these methods suffer from the following problems: Slow response speed: Mechanical relay switches have a slow switching speed, which may cause output voltage fluctuations during fault switching, affecting the operation of load equipment.

[0003] MOSFET back-to-back isolation: The MOSFET is controlled to turn on by the drive circuit, but there is still a loss due to on-resistance (RDS(on)). Summary of the Invention

[0004] To address the problems of existing technologies, this invention proposes a multi-channel DC power supply redundancy control circuit based on dynamic sampling resistor adjustment. The purpose of this invention is to provide a multi-channel DC power supply redundancy control circuit based on dynamic sampling resistor adjustment, which is mainly applied in fixed voltage design scenarios (server / data center power supply redundancy design, industrial automation control system power supply design, 5G base station power supply backup power supply design, medical equipment power supply design, new energy vehicle electronic system power supply design), providing a low-cost, high-response solution for high-reliability power supply scenarios.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A multi-channel DC power supply redundancy control circuit based on dynamic sampling resistor adjustment includes three redundant circuits and a supporting capacitor. The three redundant circuits are connected in parallel for output. One end of the supporting capacitor is connected to the output terminal of the parallel output of the redundant circuits, and the other end of the supporting capacitor is grounded. Redundant circuits are used to achieve seamless switching between primary and backup circuits, ensuring stable and reliable power supply; support capacitors are used to maintain stable output voltage during primary and backup circuit switching, compensate for power supply response delay, and prevent significant voltage drops. The redundant circuit includes an AC / DC conversion circuit to convert AC voltage to DC voltage; DC / DC converter circuits are used to convert rectified DC voltage into the required isolated DC load voltage; The sampling filter capacitor is used to filter the sampled voltage and remove high-frequency noise and interference from the circuit. The sampling and adjustment circuit is used to adjust the sampling resistor so that the output voltages of the main and backup circuits are different, thereby achieving seamless switching between the main and backup circuits. Anti-reverse diode, used to prevent reverse voltage from flowing back onto the output side; The output filter capacitor, composed of electrolytic capacitors and film capacitors, can filter out low-frequency ripple, effectively suppress high-frequency noise, improve transient response speed and reduce voltage drop; The AC / DC conversion circuit is connected to the DC / DC conversion circuit. The output of the DC / DC conversion circuit is connected to the sampling filter capacitor. At the same time, the output of the DC / DC conversion circuit is connected to the voltage sampling resistor and the control voltage sampling resistor. The control voltage sampling resistor is connected to one end of the regulating resistor, and the other end of the regulating resistor is connected to the regulating MOSFET.

[0006] Further sampling and conditioning circuitry includes a voltage sampling resistor, a control voltage sampling resistor, a regulating resistor, a filter capacitor, and a regulating MOSFET; Further sampling and regulation circuitry includes a voltage sampling resistor, a control voltage sampling resistor, a regulating resistor, a filter capacitor, and a regulating isolation optocoupler; using an isolation optocoupler instead of a MOSFET enables isolated control and reduces interference from switching noise.

[0007] The further sampling and adjustment circuit includes a voltage sampling resistor, a control voltage sampling resistor, multiple adjustment resistors, a filter capacitor, and multiple adjustment MOSFETs; the multiple adjustment resistors and multiple adjustment MOSFETs form an adjustment network to achieve precise adjustment of multiple output voltage levels.

[0008] The voltage sampling resistor in the further sampling and regulation circuit is used to detect the output voltage through a resistor divider network, convert the electrical parameters into a processable voltage signal, and feed it back to the background controller to detect the output voltage in real time and control the opening and closing of the output voltage so as to switch the backup circuit when the output voltage is abnormal.

[0009] The control sampling resistor in the further sampling and adjustment circuit is used to detect the output voltage through a resistor divider network, convert the electrical parameters into a processable voltage signal, and feed it back to the control circuit to ensure the stability of the output voltage.

[0010] Furthermore, the regulating resistor in the sampling and regulating circuit is used to regulate the output voltage by connecting it in parallel with or disconnecting it from the lower end of the sampling resistor.

[0011] Compared with existing technologies, the beneficial effects of the invention are: the use of an adjustable sampling resistor network to monitor and dynamically adjust the voltage of each channel in real time, achieving precise control; the combination of MOSFET and operational amplifier control to reduce output voltage fluctuations during power failure switching, avoiding impact on the operation of load equipment; and hardware closed-loop control, which responds faster than software solutions and ensures seamless switching. Attached Figure Description

[0012] Other features, objects, and advantages of the invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings.

[0013] Figure 1 Design of the sampling and adjustment circuit for this invention Figure 1 ; Figure 2 Design of the sampling and adjustment circuit for this invention Figure 2 ; Figure 3 Design of the sampling and adjustment circuit for this invention Figure 3 ; Figure 4 This is the circuit design diagram of the present invention; Figure 5 The circuit design of this invention Figure 1 ; Figure 6 The circuit design of this invention Figure 2 . Detailed Implementation

[0014] The present invention will be further described in detail below through embodiments. These embodiments are only used to illustrate the present invention and do not limit the scope of the present invention.

[0015] A multi-channel DC power supply redundancy control circuit based on dynamic sampling resistor adjustment includes three redundant circuits and a supporting capacitor. The three redundant circuits are connected in parallel for output. One end of the supporting capacitor is connected to the output terminal of the parallel output of the redundant circuits, and the other end of the supporting capacitor is grounded.

[0016] Redundant circuits are used to achieve seamless switching between primary and backup circuits, ensuring stable and reliable power supply; support capacitors are used to maintain stable output voltage during primary and backup circuit switching, compensate for power supply response delay, and prevent significant voltage drops. The redundant circuit includes an AC / DC conversion circuit, which is used to convert AC voltage to DC voltage, and can be either uncontrolled rectification or active rectification. DC / DC converter circuits are used to convert rectified DC voltage into the required isolated DC load voltage; The sampling filter capacitor is used to filter the sampled voltage and remove high-frequency noise and interference from the circuit. The sampling and adjustment circuit is used to adjust the sampling resistor so that the output voltages of the main and backup circuits are different, thereby achieving seamless switching between the main and backup circuits. Anti-reverse diode, used to prevent reverse voltage from flowing back onto the output side; The output filter capacitor, composed of electrolytic capacitors and film capacitors, can filter out low-frequency ripple, effectively suppress high-frequency noise, improve transient response speed and reduce voltage drop; The AC / DC conversion circuit is connected to the DC / DC conversion circuit. The output of the DC / DC conversion circuit is connected to the sampling filter capacitor. At the same time, the output of the DC / DC conversion circuit is connected to the voltage sampling resistor and the control voltage sampling resistor. The control voltage sampling resistor is connected to one end of the regulating resistor, and the other end of the regulating resistor is connected to the regulating MOSFET.

[0017] The sampling and regulation circuit includes a voltage sampling resistor, a control voltage sampling resistor, an adjustment resistor, a filter capacitor, and an adjustment MOSFET; Alternatively, the sampling and regulation circuit includes a voltage sampling resistor, a control voltage sampling resistor, an adjustment resistor, a filter capacitor, and an adjustment isolation optocoupler; using an isolation optocoupler instead of a MOSFET can achieve isolated control and reduce interference from switching noise.

[0018] Alternatively, the sampling and regulation circuit includes a voltage sampling resistor, a control voltage sampling resistor, multiple regulating resistors, a filter capacitor, and multiple regulating MOSFETs; the multiple regulating resistors and multiple regulating MOSFETs form a regulation network to achieve precise regulation of multiple output voltage levels.

[0019] The voltage sampling resistor in the sampling and regulation circuit is used to detect the output voltage through a resistor divider network, convert the electrical parameters into a processable voltage signal, and feed it back to the background controller. It can detect the output voltage in real time and control the opening and closing of the output voltage so as to switch to the backup circuit when the output voltage is abnormal.

[0020] The control sampling resistor in the sampling and regulation circuit is used to detect the output voltage through a resistor voltage divider network, convert the electrical parameters into a processable voltage signal, and feed it back to the control circuit to ensure the stability of the output voltage.

[0021] The regulating resistor in the sampling and regulating circuit is used to adjust the output voltage by connecting it in parallel with or disconnecting it from the lower end of the sampling resistor.

[0022] The filter capacitor in the sampling adjustment circuit is used to suppress switching noise from MOSFET operation and smooth the sampling. To prevent malfunctions in the control circuit, ceramic capacitors are generally selected.

[0023] The regulating MOSFET in the sampling and regulation circuit is controlled by the background controller, and can quickly control the regulation when the output voltage is abnormal. Connecting and disconnecting the resistor switches to the backup power supply.

[0024] The principle of the present invention will be further explained below with reference to the accompanying drawings: A multi-channel DC power supply redundancy control circuit design based on dynamic sampling resistor adjustment includes three redundant circuits and supporting capacitors. The redundant circuits include an AC / DC conversion circuit, a DC / DC conversion circuit, a sampling filter capacitor, a sampling adjustment circuit, a reverse protection diode, and an output filter capacitor. The sampling adjustment circuit includes a voltage sampling resistor, a control voltage sampling resistor, an adjustment resistor, a filter capacitor, and an adjustment MOSFET.

[0025] The principle of the multi-channel DC power supply redundancy control circuit with dynamic sampling resistor adjustment is as follows: Three redundant circuits are connected to AC voltage and output three DC voltages (Vo1, Vo2, Vo3) respectively. The three DC voltages pass through anti-reverse diodes, are connected in parallel, and are finally output as DC voltage (VOUT) through the supporting capacitor E. The three redundant circuits can work simultaneously and have outputs. The redundant circuits are controlled by the sampling adjustment circuit, so that the three DC voltages (Vo1, Vo2, Vo3) are different. The output voltage of the main circuit is higher than that of the two backup circuits, so that the backup circuits are in a static no-load operation state.

[0026] The principle of redundant circuits is as follows, taking the first circuit as an example: After the circuit is powered on, it first undergoes AC / DC and DC / DC conversion to obtain the output voltage (Vo1). At this moment, the output voltage... When the regulating MOSFET in the closed sampling and regulation circuit is closed, the regulating resistor (R1) is connected in parallel with the lower resistor (rs1) of the control voltage sampling resistor. At this moment, the output voltage is: Vo1 2 Greater than Vo1 1 The remaining two backup circuits can only operate under static no-load conditions because the regulating MOSFET in the sampling and regulation circuit is disconnected, resulting in an output voltage lower than the main circuit voltage. (1) Normal power supply mode Main circuit path 1: The input AC power is rectified by AC / DC, converted by DC / DC, and filtered by voltage (CV1) to output a stable voltage (Vo1). 1 The voltage sampling resistor (RV1) outputs a sampled voltage (VS1), which is read and processed by the controller (such as a microcontroller). The controller sends a control signal (KZ1) to close the regulating MOSFET (M1), so that the regulating resistor (R1) is connected to the circuit, and the output voltage (Vo1) is increased. 2 ), to supply power to the load.

[0027] Backup circuit 2 and 3: Main circuit 1: The connected AC power supply undergoes AC / DC rectification, DC / DC conversion, voltage filtering (CV), and outputs a stable voltage (Vo). 1The voltage sampling resistor (RV) outputs a sampled voltage (VS) for the controller (such as a microcontroller) to read and process. Since the main circuit is working, the controller does not send a control signal (KZ1), the regulating MOSFET (M1) is turned off, the regulating resistor (R1) is not connected to the circuit, the output voltage is less than the main circuit voltage, and it can only operate under static no-load conditions.

[0028] (2) Fault operation mode When the controller detects a fault shutdown or undervoltage in the main circuit (path 1) (VS1 decreases), the controller disconnects the main circuit regulating MOSFET (M1) and closes the backup circuit regulating MOSFET (M2) to maintain power supply to the backup circuit (path 2). When the backup circuit (path 2) fails to power down or experiences undervoltage, the controller disconnects the backup circuit regulating MOSFET (M2) and closes the backup circuit regulating MOSFET (M3) to maintain power supply to the backup circuit (path 3). If the backup circuit (path 2) fails to power down after power-on, when the main circuit (path 1) fails to power down or experiences undervoltage, the controller skips the backup circuit (path 2) and closes the backup circuit regulating MOSFET (M3) to maintain power supply to the backup circuit (path 3).

[0029] The specific contents of the controller's control logic (1) Normal power supply mode Main circuit 1: AC power is rectified by AC / DC, converted by DC / DC, and filtered to output a stable voltage Vo1_1; The voltage sampling resistor (RV1) samples to obtain VS1, which is then read by the controller; The controller issues KZ1, closes M1, connects R1, and outputs voltage Vo1_2 to supply power to the load. Backup circuit 2 and 3: Because the main circuit is working, the controller does not issue KZ2 / KZ3, M2 / M3 is open, the output voltage is lower than the main circuit, and it only runs under no-load. (2) Fault working mode When the main circuit (1) is faulty or undervoltage: The controller detects a drop in VS1, opens KZ1 (M1 is open), and closes KZ2 (M2 is closed), switching to power supply to the 2nd circuit. If the 2nd circuit is also faulty: The controller opens KZ2, closes KZ3, and switches to power supply to the 3rd circuit. If the 2nd circuit is faulty from the start: When the main circuit is faulty, the 2nd circuit is skipped directly, KZ3 is closed, and power is supplied by the 3rd circuit. By controlling the on / off state of each MOSFET, the main circuit voltage is made higher than the backup circuit, thus achieving "main circuit priority and backup circuit hot backup"; the controller reads the sampled voltage of each circuit in real time and decides to switch according to the voltage status; once the main circuit fails, it immediately switches to the next circuit to ensure power supply continuity. The controller ensures that the output voltages of the three redundant circuits are different through a sampling and adjustment circuit. The output voltage (Vo1_2) of the main circuit (e.g., the first path) is the highest.

[0030] The output voltages (Vo2_1, Vo3_1) of the backup circuits (channels 2 and 3) are lower than those of the main circuit.

[0031] Due to the voltage difference and the fact that each output terminal has a reverse protection diode connected in parallel, the main circuit with the highest voltage will naturally supply power to the load, while the backup circuit is in a static no-load (hot backup) state due to the low voltage and does not output current.

[0032] The controller (such as a microcontroller) determines its operating status by continuously monitoring the sampled voltages (VS1, VS2, VS3) of each channel and executes the following switching logic: (1) Normal power supply mode Status: Main circuit (channel 1) voltage is normal.

[0033] Controller actions: The control signal KZ1 is sent to close the regulating MOSFET (M1) of the main circuit, so that its output voltage rises to the maximum and bears the entire load.

[0034] KZ2 and KZ3 are not issued, and the MOSFETs (M2, M3) of the backup circuit are kept off, so that their output voltage is low and they are in hot backup state.

[0035] (2) Fault operation mode and fault skipping mechanism Triggering condition: The controller detects that the sampling voltage of the current power supply circuit has decreased (below the set threshold) and determines that it is faulty or undervoltage.

[0036] Switching logic (in order of priority): Main circuit (channel 1) fault: The controller disconnects KZ1 (M1 disconnects), causing the first channel to lose power.

[0037] Close KZ2 (M2 closed) to boost the second output voltage, making it the new main circuit and taking over the load.

[0038] The second circuit (new main circuit) is also faulty: The controller disconnects KZ2 (M2 disconnects), causing the second channel to lose power.

[0039] Close KZ3 (M3 closed) to boost the third output voltage and make it take over the load.

[0040] Skip fault path mechanism: Scenario: Circuit 2 is already faulty (unable to work properly) when the system starts up.

[0041] Logic: When the main circuit (channel 1) fails, the controller attempts to switch to channel 2, but detects an abnormal state of channel 2 (such as no response or low VS2). At this time, the controller will directly skip channel 2, not send the KZ2 signal, but directly send the KZ3 signal to activate channel 3 for power supply.

[0042] The principle of the sampling and adjustment circuit is as follows: When the circuit is connected to a power source and starts working, the output voltage (VO) 1 The voltage sampling resistor (RV) outputs a sampled voltage (VS). The controller (such as a microcontroller) reads the sampled voltage and outputs a control signal (KZ) to close the regulating MOSFET (M), so that the regulating resistor (R) is connected to the circuit, and the output voltage (Vo) is increased. 2 ), supplying power to the load. When the regulating MOSFET (M) is off, the circuit output voltage Vo 1 When the MOSFET (M) is closed, the circuit output voltage Vo 2 Output voltage Vo 1 and Vo 2 All voltages must be within the specified voltage range, voltage Vo 1 Not lower than the lower limit of the normal supply voltage, voltage Vo 2 It should not exceed the upper limit of the normal power supply voltage.

[0043] If multiple output voltage levels Vo are required, the MOSFETs can be controlled at different frequencies, effectively connecting the regulating resistors in the circuit; alternatively, a hierarchical control network can be constructed using multiple regulating resistors and MOSFETs. The sampling regulation circuit contains multiple regulating resistors (R1, R2, R3…) with different resistance values, each connected in series with an independent regulating MOSFET (M1, M2, M3…). By selectively closing one or more MOSFETs, the controller can connect different resistor combinations in parallel to the sampling network, thereby achieving multiple discrete and precise output voltage levels. Each voltage level is determined by a fixed resistor combination, resulting in a highly stable output voltage unaffected by factors such as switching frequency.

[0044] Different models of optocouplers and voltage references (such as TL431 / TL432) can also be selected to achieve isolated sampling and control.

[0045] The above description is only used to help understand the method and core idea of ​​the present invention. For those skilled in the art, other types of multi-channel DC power supply redundancy control circuits based on dynamic sampling resistor adjustment (such as voltage signal isolation sampling method, voltage signal digital sampling method, isolation control method, etc.) designed according to the guiding idea of ​​the present invention still fall within the protection scope of the present invention.

Claims

1. A multi-channel DC power supply redundancy control circuit based on dynamic sampling resistor adjustment, characterized in that, The redundant circuit includes three redundant circuits and a support capacitor, the three redundant circuits are connected in parallel to output, one end of the support capacitor is connected with the output end of the redundant circuit output in parallel, and the other end of the support capacitor is grounded. The redundant circuit is used for realizing seamless switching of the main and standby circuits, guaranteeing stable and reliable power supply, the support capacitor is used for maintaining stable output voltage during switching of the main and standby circuits, compensating for power response delay, and avoiding large voltage drop. The redundant circuit includes an AC / DC conversion circuit, which is used for converting alternating voltage into direct current voltage. The DC / DC conversion circuit is used for converting the rectified direct current voltage into required isolated direct current load voltage. The sampling filter capacitor is used for filtering the sampling voltage, and filtering high-frequency noise and clutter in the circuit. The sampling adjustment circuit is used for adjusting the sampling resistor, so that the output voltages of the main and standby circuits are different, and seamless switching of the main and standby circuits is realized. The anti-reverse diode is used for preventing reverse voltage on the output side. The output filter capacitor is composed of an electrolytic capacitor and a film capacitor, which can filter low-frequency ripple, suppress high-frequency noise, improve transient response speed and reduce voltage drop. The AC / DC conversion circuit is connected with the DC / DC conversion circuit, the output end of the DC / DC conversion circuit is connected with the sampling filter capacitor, and the output end of the DC / DC conversion circuit is connected with the voltage sampling resistor and the control voltage sampling resistor.

2. The redundant control circuit for multiple DC power supplies based on dynamic sampling resistance adjustment according to claim 1, wherein, The sampling adjustment circuit includes a voltage sampling resistor, a control voltage sampling resistor, an adjustment resistor, a filter capacitor and an adjustment MOSFET.

3. The redundant control circuit for multiple DC power supplies based on dynamic sampling resistance adjustment as claimed in claim 1, wherein, The sampling adjustment circuit includes a voltage sampling resistor, a control voltage sampling resistor, an adjustment resistor, a filter capacitor and an adjustment isolation optocoupler. Using the isolation optocoupler instead of the MOSFET can realize isolation control and reduce the interference of switching noise.

4. The redundant control circuit for multiple DC power supplies based on dynamic sampling resistance adjustment as claimed in claim 1, wherein, The sampling adjustment circuit includes a voltage sampling resistor, a control voltage sampling resistor, a plurality of adjustment resistors, a filter capacitor and a plurality of adjustment MOSFETs; the plurality of adjustment resistors and the plurality of adjustment MOSFETs form an adjustment network to realize precise adjustment of a plurality of output voltage grades.

5. The redundant control circuit for multiple DC power supplies based on dynamic sampling resistance adjustment as claimed in claim 1 wherein, The voltage sampling resistor in the sampling adjustment circuit is used for detecting the output voltage through a resistance voltage dividing network, converting the electrical parameter into a processable voltage signal, feeding back to the background controller, detecting the output voltage in real time, and controlling the opening and closing of the output voltage to switch the standby circuit when the output voltage is abnormal.

6. The redundant control circuit for multiple DC power supplies based on dynamic sampling resistance adjustment as claimed in claim 5 wherein, The control sampling resistor in the sampling adjustment circuit is used for detecting the output voltage through a resistance voltage dividing network, converting the electrical parameter into a processable voltage signal, feeding back to the control circuit, and ensuring the stability of the output voltage.

7. The redundant control circuit for multiple DC power supplies based on dynamic sampling resistance adjustment as claimed in claim 6 wherein, The adjustment resistor in the sampling adjustment circuit is used for adjusting the output voltage by being connected in parallel with the lower end of the sampling resistor and being disconnected.

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