Low dropout redundant backup priority power supply seamless switching circuit

Abstract

This utility model discloses a low-dropout redundant backup priority power supply seamless switching circuit. The priority input positive (P1) is connected to the backup input positive (P3) and simultaneously to the output positive (P5); the priority input negative (P2) is connected to the backup input negative (P4) and simultaneously to the output negative (P6); the priority input positive (P1) is connected to one end of resistor one (R1), and the other end of resistor one (R1) is connected to the gate of the priority power supply control MOS (VM1). Resistor three (R3), capacitor one (C1), and Zener diode one (VZ1) are connected in parallel between the gate and source of the priority power supply control MOS (VM1); the priority input negative (P2) is connected to the drain of the priority power supply control MOS (VM1) and connected to the gate of the backup power supply control MOS (VM2) through diode one (VD1). The use of MOS transistors achieves miniaturized redundant dual-input priority control. The on-state voltage drop of the MOS transistors is small, having minimal impact on power supply accuracy; therefore, this circuit can achieve seamless switching of low-dropout redundant backup power supply.

Description

Technical Field

[0001] This utility model relates to a DC power supply redundancy backup power supply technology, and more particularly to a low-dropout redundancy backup priority power supply seamless switching circuit. Background Technology

[0002] With the rapid development of power electronics technology, DC power supplies have been widely used in industries such as national defense, aerospace, consumer electronics, communications, new energy, and inverters. Some DC-powered equipment requires redundant backup power supply, that is, one power supply is the priority power supply, which comes from the mains input or the next level of redundant backup power supply, and the other is the backup power supply, which comes from the input of the battery, etc. It is required that the priority power supply be used first, and the backup power supply be used when the priority power supply has no input. At the same time, it is necessary to seamlessly switch to the backup power supply during the switch from the priority power supply to the backup power supply, and ensure that the load does not lose power during the switch.

[0003] Currently, it is difficult to find circuit devices on the market that can achieve seamless switching of low-dropout redundancy backup power supply. Common methods include using diodes for backup power supply or relays for switching. The advantage of this protection method is its simplicity. However, diode backup power supply can only prioritize power supplies at voltages slightly higher than the backup supply voltage, and the diode voltage drop prevents high-precision power supply. Relay switching circuits suffer from a temporary power outage during the switching process, requiring additional energy storage to ensure uninterrupted power during switching. Furthermore, relays are relatively large and difficult to miniaturize. Therefore, using relays makes seamless switching difficult. Thus, it is essential to implement a seamless switching circuit for low-dropout redundancy backup power supply.

[0004] The design of the so-called low-dropout redundancy backup priority power supply seamless switching circuit is to ensure that the circuit can achieve low-dropout high-precision backup power supply, and also to achieve seamless switching between the two input power supplies, so as to avoid unnecessary trouble for users caused by power failure during customer load switching. Therefore, the research on a circuit that can achieve both low-dropout redundancy backup priority and seamless input switching has become the key to technical research.

[0005] Existing technology 1:

[0006] The circuit diagram for the redundancy backup priority power supply scheme one is shown below. Figure 1 The redundant priority power supply and the backup power supply are connected in parallel via diodes VD1 and VD2 to supply power to the load. Achieving backup priority power supply via diodes requires consideration of diode voltage drop, and heat dissipation is necessary when the supply current is too high. Furthermore, to achieve priority power supply, the input voltage of the priority power supply needs to be slightly higher than that of the backup power supply. The advantages of this scheme are its simple circuitry and seamless switching capability.

[0007] Disadvantages of the redundancy backup priority power supply scheme 1:

[0008] 1) The diode voltage drop needs to be considered, and the priority supply voltage is higher than the backup input supply voltage, so the power supply accuracy is poor;

[0009] 2) When the current is large, the diode heat dissipation needs to be considered, such as adding a heat sink or even forced cooling.

[0010] Existing technology 2:

[0011] The circuit diagram for the redundant backup priority power supply scheme two is shown below. Figure 2 The redundant priority power supply and backup power supply are connected at position P1. When the priority power supply is input, R5 detects the priority power supply and limits the gate voltage of VM3 to approximately 12V via VZ1. C3 filters the gate voltage of VM3 to prevent high-frequency jitter, and R6 enables rapid discharge of the VM3 gate. When the priority power supply is normal, VM3 conducts, and the relay coil reaches the pull-in voltage, activating the relay. The normally open contact of the relay switch is open, and the output of P5 is the priority power supply, providing energy to the load. The backup power supply is input from P3. When there is no priority power supply input, the normally open contact of the relay opens, and the backup power supply provides energy to the load through the normally closed contact of the relay. The load is connected to P5. During the switching process between priority and backup power supplies, due to the brief power disconnection caused by the mechanical contact switching during relay switching, a large-capacity capacitor C4 is needed to maintain power supply during the switching process. Therefore, an appropriate capacitor needs to be selected based on the load to maintain power supply. This circuit can achieve priority power supply and seamless switching.

[0012] Disadvantages of the redundant backup priority power supply scheme two:

[0013] This method of redundant priority power supply and backup power supply can achieve priority power supply and seamless power supply. However, it requires a large capacitor to maintain power supply during relay switching. Therefore, the relays used in this solution are large in size and require large-capacity capacitors for energy storage, making it impossible to achieve miniaturization design.

[0014] In view of the above, this utility model is hereby proposed. Utility Model Content

[0015] The purpose of this invention is to provide a low-dropout redundant backup priority power supply seamless switching circuit to solve the above-mentioned technical problems existing in the prior art.

[0016] The objective of this utility model is achieved through the following technical solution:

[0017] The low-dropout redundancy backup priority power supply seamless switching circuit of this utility model includes:

[0018] Prioritize positive input P1, prioritize negative input P2, back up positive input P3, back up negative input P4, output positive P5, output negative P6;

[0019] Prioritize input P1 and connect it to backup input P3, while simultaneously connecting it to output P5;

[0020] Prioritize input negative P2 to connect to backup input negative P4, and simultaneously connect to output negative P6;

[0021] The positive input P1 is connected to one end of resistor R1, and the other end of resistor R1 is connected to the gate of the priority power supply control MOSVM1. Resistor R3, capacitor C1 and Zener diode VZ1 are connected in parallel between the gate and source of the priority power supply control MOSVM1.

[0022] The priority input negative P2 is connected to the drain of the priority power supply control MOSVM1, and is connected to the gate of the backup power supply control MOSVM2 through diode VD1.

[0023] Compared with the prior art, the low-dropout redundant backup priority power supply seamless switching circuit provided by this utility model uses MOSFETs to realize miniaturized redundant dual-input priority control and seamless switching between priority power supply and backup power supply. When the priority power supply circuit and the backup power supply are connected, the circuit controls the priority input to supply power to the load. When the priority power supply has no power, the circuit detects and switches to the backup power supply input, seamlessly and quickly supplying power to the load. Moreover, the on-state voltage drop of the MOSFET is small, which has minimal impact on the power supply accuracy. Therefore, this circuit can realize seamless switching of low-dropout redundant backup power supply. Attached Figure Description

[0024] Figure 1 This is a circuit diagram of the redundancy backup priority power supply scheme 1 in the existing technology;

[0025] Figure 2 The circuit diagram is for the second redundant backup priority power supply scheme in the existing technology;

[0026] Figure 3 A schematic diagram of a low-dropout redundancy backup priority power supply seamless switching circuit provided for an embodiment of this utility model. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments, which do not constitute a limitation on the present utility model. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0028] First, the following explanations are provided for the terms that may be used in this article:

[0029] The terms "comprising," "including," "containing," "having," or other similar semantic descriptions should be interpreted as non-exclusive inclusion. For example, including a technical feature element (such as raw material, component, ingredient, carrier, dosage form, material, size, part, component, mechanism, device, step, process, method, reaction conditions, processing conditions, parameter, algorithm, signal, data, product or article of manufacture, etc.) should be interpreted as including not only the expressly listed technical feature element, but also other technical feature elements that are not expressly listed and are well-known in the art.

[0030] The term "composed of" excludes any technical features not expressly listed. When used in a claim, it closes the claim to exclude all technical features other than those expressly listed, except for associated conventional impurities. If the term appears only in a clause of a claim, it limits the claim to the elements expressly listed in that clause; elements recited in other clauses are not excluded from the overall claim.

[0031] The contents not described in detail in the embodiments of this utility model are existing technologies known to those skilled in the art. Where specific conditions are not specified in the embodiments of this utility model, they shall be performed according to conventional conditions in the art or conditions recommended by the manufacturer. Reagents or instruments used in the embodiments of this utility model whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0032] This utility model discloses a low-dropout redundancy backup priority power supply seamless switching circuit, comprising:

[0033] Prioritize positive input P1, prioritize negative input P2, back up positive input P3, back up negative input P4, output positive P5, output negative P6;

[0034] Prioritize input P1 and connect it to backup input P3, while simultaneously connecting it to output P5;

[0035] Prioritize input negative P2 to connect to backup input negative P4, and simultaneously connect to output negative P6;

[0036] The positive input P1 is connected to one end of resistor R1, and the other end of resistor R1 is connected to the gate of the priority power supply control MOSVM1. Resistor R3, capacitor C1 and Zener diode VZ1 are connected in parallel between the gate and source of the priority power supply control MOSVM1.

[0037] The priority input negative P2 is connected to the drain of the priority power supply control MOSVM1, and is connected to the gate of the backup power supply control MOSVM2 through diode VD1.

[0038] The source of the priority power supply control MOSVM1 is connected to the negative output P6, and a capacitor C5 is connected in parallel between the positive output P5 and the negative output P6.

[0039] The backup input P3 is connected to one end of resistor R2, and the other end of resistor R2 is connected to the gate of backup power supply control MOSVM2. Resistor R4, capacitor C2 and Zener diode VZ2 are connected in parallel between the gate and source of backup power supply control MOSVM2.

[0040] The backup input negative P4 is connected to the drain of the backup power supply control MOSVM2, and the source of the backup power supply control MOSVM2 is connected to the output negative P6.

[0041] The system employs MOSFETs for seamless and rapid low-dropout switching between priority and backup inputs, enabling control of both priority and backup power supply.

[0042] In summary, the low-dropout redundant backup priority power supply seamless switching circuit of this utility model avoids the shortcomings of the prior art solutions one and two. It uses MOSFETs to realize miniaturized redundant dual-input priority control and seamless switching between priority power supply and backup power supply. When the priority power supply circuit and the backup power supply are connected, the circuit controls the priority input to supply power to the load. When the priority power supply is not supplying power, the circuit detects and switches to the backup power supply input, seamlessly and quickly supplying power to the load. Moreover, the on-state voltage drop of the MOSFET is small, and the impact on the power supply accuracy is minimal. Therefore, this circuit can realize seamless switching of low-dropout redundant backup power supply.

[0043] To more clearly demonstrate the technical solution and effects provided by this utility model, the following detailed description of the embodiments of this utility model is provided with reference to specific examples.

[0044] Example 1

[0045] The low-dropout redundancy backup priority power supply seamless switching circuit is described in [link to circuit description]. Figure 3P1 and P2 are priority power supply input ports, with P1 being the positive priority input and P2 the negative priority input. P3 and P4 are backup power supply input ports, with P3 being the positive backup input and P4 the negative backup input. P5 and P6 are output ports, with P5 being the positive output and P6 the negative output. The positive priority input of P1 is connected to the positive backup input of P3 and also to the positive output of P5. The positive priority input of P1 is connected to one end of resistor R1, and the other end of resistor R1 is connected to the gate of VM1. VM1 is the priority power supply control MOS. R3, C1, and VZ1 are connected in parallel at the gate and source of VM1 to provide drive power for VM1. P2 is the priority input... The negative terminal of VM1 is connected to the drain, and VD1 is connected to the gate of VM2 for priority power control to shut down the drive of VM2. The source of VM1 is connected to P6 to output the negative terminal. A C5 is connected in parallel between the positive and negative terminals of the output for output filtering. The positive terminal of P3 is connected to one end of resistor R2, and the other end of resistor R2 is connected to the gate of VM2. VM2 is a backup power control MOS. R4, C2, and VZ2 are connected in parallel between the gate and source of VM2 to provide drive power for VM2. The negative terminal of P4 is connected to the drain of VM2, and VD1 is connected to the gate of VM2 for priority power control to shut down the drive of VM2. The source of VM2 is connected to P6 to output the negative terminal.

[0046] The beneficial effects of this utility model's technical solution are:

[0047] 1) This circuit can meet the user's requirements for priority power supply and seamless switching when the user has priority power supply and seamless switching for redundant backup power supply.

[0048] 2) The use of a MOSFET with low on-resistance for control has minimal impact on power supply accuracy.

[0049] The key technical points of this utility model are:

[0050] MOSFETs are used for seamless and fast low-dropout switching between priority input and backup input, and to control priority power supply and backup power supply.

[0051] The above description is merely a preferred embodiment of this utility model, but the scope of protection of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this utility model should be included within the scope of protection of this utility model. Therefore, the scope of protection of this utility model should be determined by the scope of the claims. The information disclosed in the background section is intended only to enhance the understanding of the overall background technology of this utility model and should not be construed as an admission or implication in any way that such information constitutes prior art known to those skilled in the art.

Claims

1. A low-dropout redundancy backup priority power supply seamless switching circuit, characterized in that, include: Priority input positive (P1), priority input negative (P2), backup input positive (P3), backup input negative (P4), output positive (P5), output negative (P6). The positive input (P1) is connected to the backup positive input (P3), and the positive output (P5) is also connected. Prioritize the negative input (P2) and connect it to the backup negative input (P4), while simultaneously connecting it to the negative output (P6). The positive input (P1) is connected to one end of resistor one (R1), and the other end of resistor one (R1) is connected to the gate of the priority power supply control MOS (VM1). Resistor three (R3), capacitor one (C1), and Zener diode one (VZ1) are connected in parallel between the gate and source of the priority power supply control MOS (VM1). The priority input negative (P2) is connected to the drain of the priority power supply control MOS (VM1) and connected to the gate of the backup power supply control MOS (VM2) through diode one (VD1).

2. The low-drop redundancy backup priority power supply seamless switchover circuit of claim 1, wherein, The source of the priority power supply control MOS (VM1) is connected to the negative output (P6), and a capacitor (C5) is connected in parallel between the positive output (P5) and the negative output (P6).

3. The low-drop redundancy backup priority power supply seamless switchover circuit of claim 2, wherein, The backup input positive (P3) is connected to one end of resistor two (R2), and the other end of resistor two (R2) is connected to the gate of the backup power supply control MOS (VM2). Resistor four (R4), capacitor two (C2), and Zener diode two (VZ2) are connected in parallel between the gate and source of the backup power supply control MOS (VM2). The backup input negative (P4) is connected to the drain of the backup power supply control MOS (VM2), and the source of the backup power supply control MOS (VM2) is connected to the output negative (P6).

Images