Electric equipment and multichannel isolation power supply circuit thereof

Abstract

The utility model discloses electric equipment and a multichannel isolation power supply circuit thereof. The circuit comprises a power supply transformer, a power supply circuit and a compensation control circuit. The secondary side of the power supply transformer is provided with a main winding and an auxiliary winding. The power supply circuit is provided with a first power supply interface connected with the main winding and a second power supply interface connected with the auxiliary winding. The compensation control circuit comprises a first end and a second end, the first end is connected with the first power supply interface, the second end is connected with the second power supply interface, and when the compensation control circuit detects that the voltage of the second end is lower than the minimum power supply voltage, the first end and the second end are conducted, and the main winding is controlled to charge the auxiliary winding; the voltage judgment and compensation of the auxiliary winding are realized, the power loss and the heating value are not increased, and the power supply quality of the circuit is improved.

Description

Technical Field

[0001] This utility model relates to power supply technology, and in particular to an electrical device and its multi-channel isolated power supply circuit. Background Technology

[0002] In isolated power supply circuits, an auxiliary winding is often added to the secondary winding of the transformer to supply power to the load. This is done to simplify the circuit, reduce costs, and minimize losses.

[0003] However, during power supply, the voltage of the auxiliary winding decreases as the voltage of the secondary winding decreases, and the voltage drop of the auxiliary winding is even greater under light load conditions. The common solution in current technology is to increase the number of turns in the auxiliary winding. However, this approach not only increases power loss under high voltage and full load conditions but also increases the heat generated in the power supply circuit. Utility Model Content

[0004] This invention provides an electrical device and its multi-channel isolated power supply circuit, which solves the problem of unstable power supply to the auxiliary winding without increasing power loss and heat generation.

[0005] According to one aspect of the present invention, a multi-channel isolated power supply circuit is provided, the multi-channel isolated power supply circuit comprising: a power supply transformer, a power supply circuit, and a compensation control circuit;

[0006] The secondary winding of the power supply transformer is provided with a main winding and an auxiliary winding, and the power supply circuit is provided with a first power supply interface connected to the main winding and a second power supply interface connected to the auxiliary winding.

[0007] The compensation control circuit includes a first terminal and a second terminal. The first terminal is connected to the first power supply interface, and the second terminal is connected to the second power supply interface. When the compensation control circuit detects that the voltage of the second terminal is lower than the minimum power supply voltage, it turns on the first terminal and the second terminal to control the main winding to charge the auxiliary winding.

[0008] Optionally, one end of the main winding is connected to the first power supply interface, and the other end is connected to the first ground terminal; one end of the auxiliary winding is connected to the second power supply interface, and the other end is connected to the second ground terminal.

[0009] The power supply circuit is further provided with a first capacitor and a second capacitor. The first capacitor is connected between the first power supply interface and the first grounding terminal, and the second capacitor is connected between the second power supply interface and the second grounding terminal.

[0010] Optionally, the power supply circuit further includes a first unidirectional conductor and a second unidirectional conductor;

[0011] The first unidirectional conductor is disposed between one end of the main winding and the first power supply interface, wherein the positive conduction direction of the first unidirectional conductor is from one end of the main winding to the first power supply interface;

[0012] The second unidirectional conductor is disposed between one end of the auxiliary winding and the second power supply interface, wherein the positive conduction direction of the second unidirectional conductor is from one end of the auxiliary winding to the second power supply interface.

[0013] Optionally, the compensation control circuit further includes a switching controller, one end of which is connected to the first terminal, the other end of which is connected to the second terminal, and the control terminal of which is connected to the first ground terminal. When the voltage difference between the control terminal and the second terminal exceeds a preset voltage, the switching controller controls both ends of the controller to conduct.

[0014] Optionally, the compensation control circuit further includes a clamping device, which is disposed between the control terminal of the on / off controller and the first ground terminal, and the clamping voltage of the clamping device is equal to the sum of the preset voltage and the minimum supply voltage.

[0015] Optionally, the on / off controller includes an NPN transistor, and the collector of the NPN transistor serves as the control terminal of the on / off controller;

[0016] The compensation control circuit includes a voltage regulator resistor, which is disposed between the first power supply interface and the collector of the NPN transistor. The collector of the NPN transistor is connected to the first power supply interface, and the emitter of the NPN transistor is connected to the second power supply interface. The emitter-junction voltage drop of the NPN transistor is equal to the preset voltage.

[0017] Optionally, the clamping device includes a clamping diode, the anode of which is connected to the first ground terminal, the cathode of which is connected to the control terminal of the on / off controller, and the clamping voltage of the clamping diode is equal to the sum of the preset voltage and the minimum supply voltage.

[0018] According to another aspect of the present invention, an electrical device is provided, comprising: at least two loads and a multi-channel isolated power supply circuit as described in any of the first aspects of the invention, wherein the loads are connected to the multi-channel isolated power supply circuit and are powered by the multi-channel isolated power supply circuit.

[0019] This utility model provides an electrical device and its multi-channel isolated power supply circuit, which includes a power supply transformer, a power supply circuit, and a compensation control circuit. The power supply transformer has a main winding and an auxiliary winding on its secondary winding. The power supply circuit has a first power supply interface connected to the main winding and a second power supply interface connected to the auxiliary winding. The compensation control circuit includes a first terminal and a second terminal. The first terminal is connected to the first power supply interface, and the second terminal is connected to the second power supply interface. When the compensation control circuit detects that the voltage at the second terminal is lower than the minimum supply voltage, it conducts both the first and second terminals, controlling the main winding to charge the auxiliary winding. This achieves voltage judgment and compensation for the auxiliary winding without increasing power loss or heat generation, thus improving the power supply quality of the circuit.

[0020] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this utility model, nor is it intended to limit the scope of this utility model. Other features of this utility model will become readily apparent from the following description. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A schematic diagram of a multi-channel isolated power supply circuit provided for an embodiment of this utility model;

[0023] Figure 2 A circuit diagram of another multi-channel isolated power supply circuit provided for an embodiment of this utility model;

[0024] Figure 3 This is a schematic diagram of the composition of an electrical device provided in an embodiment of the present utility model. Detailed Implementation

[0025] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention 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 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 should fall within the protection scope of the present invention.

[0026] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0027] To address the problems mentioned in the background art, this utility model provides a multi-channel isolated power supply circuit. Figure 1 This is a schematic diagram of a multi-channel isolated power supply circuit provided in an embodiment of the present invention, with reference to... Figure 1 The multi-channel isolated power supply circuit 100 includes a power supply transformer 101, a power supply circuit 102, and a compensation control circuit 103. The secondary winding of the power supply transformer 101 has a main winding W1 and an auxiliary winding W2. The power supply circuit 102 has a first power supply interface VO connected to the main winding W1 and a second power supply interface VCC connected to the auxiliary winding W2. The compensation control circuit 103 includes a first terminal a and a second terminal b. The first terminal a is connected to the first power supply interface VO, and the second terminal b is connected to the second power supply interface VCC. When the compensation control circuit 103 detects that the voltage at the second terminal b is lower than the minimum supply voltage, it connects the line between the first terminal a and the second terminal b, controlling the main winding W1 to charge the auxiliary winding W2.

[0028] Specifically, the power supply transformer 101 refers to the transformer in the multi-channel isolated power supply circuit 100 used for voltage conversion and isolation between input and output. The primary winding of the power supply transformer 101 is connected to the power supply. The secondary winding of the power supply transformer 101 is provided with a main winding W1 and an auxiliary winding W2. The main winding W1 supplies power to the first power supply interface VO, enabling the multi-channel isolated power supply circuit 100 to supply power to the load connected to the first power supply interface VO. The auxiliary winding W2 supplies power to the second power supply interface VCC, enabling the multi-channel isolated power supply circuit 100 to supply power to the load connected to the second power supply interface VCC. In the prior art, during the power supply process, the voltage supplied to the second power supply interface by the auxiliary winding decreases as the voltage of the main winding decreases. This situation is more serious when the load on the second power supply interface is light, greatly reducing the power supply stability of the power supply circuit. In this embodiment, the compensation control circuit 103 provides power compensation to the auxiliary winding W2 based on the voltage across the auxiliary winding. For example, the compensation control circuit 103 may be a component circuit including a voltage detection device and a switching controller to detect the voltage of the second power supply interface VCC. When the voltage of the second power supply interface VCC is less than the minimum power supply voltage, the circuit connects the first power supply interface VO and the second power supply interface VCC, allowing the main winding W1 to provide voltage compensation to the auxiliary winding W2. The minimum power supply voltage is the lower limit voltage of the auxiliary winding W2 of the multi-channel isolated power supply circuit 100. It can be set according to the power demand of the load connected to the downstream of the auxiliary winding W2. For example, if the load's power demand is a power supply voltage higher than 12V, then the minimum power supply voltage can be set to 11.5V.

[0029] This embodiment provides a multi-channel isolated power supply circuit, which includes a power supply transformer, a power supply circuit, and a compensation control circuit. The power supply transformer has a main winding and an auxiliary winding on its secondary winding. The power supply circuit has a first power supply interface connected to the main winding and a second power supply interface connected to the auxiliary winding. The compensation control circuit includes a first terminal and a second terminal. The first terminal is connected to the first power supply interface, and the second terminal is connected to the second power supply interface. When the compensation control circuit detects that the voltage at the second terminal is lower than the minimum supply voltage, it turns on both the first and second terminals, controlling the main winding to charge the auxiliary winding. This achieves voltage judgment and compensation for the auxiliary winding without increasing power loss or heat generation, thus improving the power supply quality of the circuit.

[0030] Optionally, Figure 2 A circuit diagram of another multi-channel isolated power supply circuit provided in this embodiment of the present invention is shown below, based on the foregoing embodiments and referring to... Figure 2One end of the main winding W1 is connected to the first power supply interface V0, and the other end is connected to the first ground terminal GND1; one end of the auxiliary winding W2 is connected to the second power supply interface VCC, and the other end is connected to the second ground terminal GND2. The power supply circuit 102 also includes a first capacitor CE1 and a second capacitor CE2. The first capacitor CE1 is connected between the first power supply interface V0 and the first ground terminal GND1, and the second capacitor CE2 is connected between the second power supply interface VCC and the second ground terminal GND2.

[0031] The power supply circuit 102 also includes a first unidirectional conductor D1 and a second unidirectional conductor D2. The first unidirectional conductor D1 is disposed between one end of the main winding W1 and the first power supply interface V0, wherein the positive conduction direction of the first unidirectional conductor D1 is from one end of the main winding W1 towards the first power supply interface V0. The second unidirectional conductor D2 is disposed between one end of the auxiliary winding W2 and the second power supply interface VCC, wherein the positive conduction direction of the second unidirectional conductor D2 is from one end of the auxiliary winding W2 towards the second power supply interface VCC.

[0032] The compensation control circuit 103 also includes a switching controller Q. One end of the switching controller Q is connected to the first terminal a, and the other end of the switching controller Q is connected to the second terminal b. The control terminal of the switching controller Q is connected to the first ground terminal GND1. When the voltage difference between the control terminal and the second terminal exceeds a preset voltage, the switching controller Q controls its two ends to conduct. The compensation control circuit 103 also includes a clamping device D3, which is disposed between the control terminal of the switching controller Q and the first ground terminal GND1. The clamping voltage of the clamping device D3 is equal to the sum of the preset voltage and the minimum supply voltage.

[0033] Specifically, the first capacitor CE1 is located between the first power supply interface VO and the first ground terminal GND1, and the second capacitor CE2 is located between the second power supply interface VCC and the second ground terminal GND2. When the voltage of the second power supply interface VCC is lower than the minimum power supply voltage, the compensation control circuit 103 controls the first power supply interface VO and the second power supply interface VCC to conduct, so that the first capacitor CE1 charges the second capacitor CE2, causing the voltage across the second capacitor CE2 to rise until the voltage of the second power supply interface VCC rises to equal the minimum power supply voltage.

[0034] The first unidirectional conductor D1 controls the circuit to maintain conduction from one end of its connected main winding W1 towards the first power supply interface VO, and cuts off in the opposite direction. The second unidirectional conductor D2 controls the circuit to maintain conduction from one end of its connected auxiliary winding W2 towards the second power supply interface VCC, and cuts off in the opposite direction. For example, the first unidirectional conductor D1 and the second unidirectional conductor D2 may each include a diode.

[0035] The on / off controller Q serves as both a voltage detection device and a voltage compensation switch for the second power supply interface VCC. Exemplarily, the on / off controller Q can be a voltage detection and on / off control component circuit composed of multiple transistors, or it can be a single transistor that meets the functional requirements. The on / off controller Q is normally off. It detects the voltage difference between its control terminal and the second power supply interface VCC. Once the voltage difference exceeds a preset voltage, the on / off controller Q turns on, causing the main winding W1 to charge the second capacitor CE2 between the second power supply interface VCC and the second ground terminal GND2, ensuring that the voltage of the second power supply interface VCC is higher than the minimum supply voltage. The preset voltage is set according to the rule that when the voltage difference between the control terminal of the on / off controller Q and the second power supply interface VCC exceeds the preset voltage, the voltage of the second power supply interface VCC is lower than the minimum supply voltage. Exemplarily, the on / off controller Q may include an NPN transistor, with the collector of the NPN transistor serving as the control terminal of the on / off controller Q. The compensation control circuit 103 also includes a voltage regulator resistor R, which is set between the first power supply interface VO and the collector of the NPN transistor. The collector of the NPN transistor is connected to the first power supply interface VO, and the emitter of the NPN transistor is connected to the second power supply interface VCC. The emitter junction voltage drop of the NPN transistor is equal to the preset voltage.

[0036] Clamping device D3 can be a clamping circuit or a clamping diode, which clamps the voltage across its terminals to a fixed value. In this embodiment, the clamping voltage of clamping device D3 is equal to the sum of the preset voltage and the minimum supply voltage. That is, the voltage at the end of clamping device D3 furthest from the second ground terminal GND2 is equal to the sum of the preset voltage and the minimum supply voltage. Correspondingly, once the voltage difference between the control terminal of the on / off controller Q and the second power supply interface VCC exceeds the preset voltage, the two ends of the on / off controller Q will be connected.

[0037] For example, during power supply, if the voltage of the second power supply interface VCC connected to the auxiliary winding W2 drops below the minimum supply voltage, the emitter junction of the NPN transistor is forward biased and the collector junction is reverse biased, the NPN transistor is turned on, the first capacitor CE1 charges the second capacitor CE2, the voltage of the second capacitor CE2 increases, until the voltage of the second capacitor CE2 rises to the minimum supply voltage, the NPN transistor is turned off, and when the secondary main winding W1 is in a high-voltage full-load output state, the NPN transistor can remain turned off.

[0038] The multi-channel isolated power supply circuit provided by this utility model includes a first capacitor, a second capacitor, a first unidirectional conductor, and a second unidirectional conductor. The first capacitor is connected between a first power supply interface and a first ground terminal, and the second capacitor is connected between a second power supply interface and a second ground terminal. The first unidirectional conductor is located between one end of the main winding and the first power supply interface, with its forward conduction direction from one end of the main winding towards the first power supply interface. The second unidirectional conductor is located between one end of the auxiliary winding and the second power supply interface, with its forward conduction direction from one end of the auxiliary winding towards the second power supply interface. The compensation control circuit also includes a switching controller and a clamping device. The clamping device is located between the control terminal of the switching controller and the first ground terminal. The clamping voltage is equal to the sum of a preset voltage and a minimum power supply voltage. When the voltage difference between the control terminal and the second terminal exceeds the preset voltage, the switching controller controls its two ends to conduct, thereby supplementing the charging of the auxiliary winding and improving the power supply stability of the circuit.

[0039] This utility model embodiment also provides an electrical device. Figure 3 This is a schematic diagram of the composition of an electrical device provided in an embodiment of the present utility model. Based on the foregoing embodiments, refer to... Figure 3 The electrical equipment 300 includes at least two loads 301 and the aforementioned multi-channel isolated power supply circuit 100. The loads 301 are connected to the multi-channel isolated power supply circuit 100 and are powered by the multi-channel isolated power supply circuit 100.

[0040] The specific embodiments described above do not constitute a limitation on the scope of protection of this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A multi-channel isolated power supply circuit, characterized in that, include: Power supply transformer, power supply circuit and compensation control circuit; The secondary winding of the power supply transformer is provided with a main winding and an auxiliary winding, and the power supply circuit is provided with a first power supply interface connected to the main winding and a second power supply interface connected to the auxiliary winding. One end of the main winding is connected to the first power supply interface, and the other end is connected to the first ground terminal; one end of the auxiliary winding is connected to the second power supply interface, and the other end is connected to the second ground terminal; the power supply circuit is also provided with a first capacitor and a second capacitor, the first capacitor is connected between the first power supply interface and the first ground terminal, and the second capacitor is connected between the second power supply interface and the second ground terminal; The compensation control circuit includes a first terminal and a second terminal. The first terminal is connected to the first power supply interface, and the second terminal is connected to the second power supply interface. When the compensation control circuit detects that the voltage at the second terminal is lower than the minimum power supply voltage, it turns on the first terminal and the second terminal to control the main winding to charge the auxiliary winding. The compensation control circuit also includes a switching controller and a clamping device. One end of the switching controller is connected to the first terminal, and the other end of the switching controller is connected to the second terminal. The control terminal of the switching controller is connected to the first ground terminal. When the voltage difference between the control terminal and the second terminal exceeds a preset voltage, the switching controller controls both ends to conduct. The clamping device is disposed between the control terminal of the switching controller and the first ground terminal. The clamping voltage of the clamping device is equal to the sum of the preset voltage and the minimum power supply voltage.

2. The multi-channel isolated power supply circuit according to claim 1, characterized in that, The power supply circuit also includes a first unidirectional conductor and a second unidirectional conductor. The first unidirectional conductor is disposed between one end of the main winding and the first power supply interface, wherein the positive conduction direction of the first unidirectional conductor is from one end of the main winding to the first power supply interface; The second unidirectional conductor is disposed between one end of the auxiliary winding and the second power supply interface, wherein the positive conduction direction of the second unidirectional conductor is from one end of the auxiliary winding to the second power supply interface.

3. The multi-channel isolated power supply circuit according to claim 1, characterized in that, The compensation control circuit further includes a clamping device, which is disposed between the control terminal of the on / off controller and the first ground terminal. The clamping voltage of the clamping device is equal to the sum of the preset voltage and the minimum supply voltage.

4. The multi-channel isolated power supply circuit according to claim 3, characterized in that, The on / off controller includes an NPN transistor, and the collector of the NPN transistor serves as the control terminal of the on / off controller. The compensation control circuit includes a voltage regulator resistor, which is disposed between the first power supply interface and the collector of the NPN transistor. The collector of the NPN transistor is connected to the first power supply interface, and the emitter of the NPN transistor is connected to the second power supply interface. The emitter-junction voltage drop of the NPN transistor is equal to the preset voltage.

5. The multi-channel isolated power supply circuit according to claim 3, characterized in that, The clamping device includes a clamping diode, the anode of which is connected to the first ground terminal, and the cathode of which is connected to the control terminal of the on / off controller. The clamping voltage of the clamping diode is equal to the sum of the preset voltage and the minimum supply voltage.

6. An electrical appliance, characterized in that, include: At least two loads and a multi-channel isolated power supply circuit as described in any one of claims 1-5, wherein the loads are connected to and powered by the multi-channel isolated power supply circuit.

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