Multi-load power supply circuit and air conditioner

Abstract

This invention discloses a multi-load power supply circuit and an air conditioner. The multi-load power supply circuit includes a power supply for supplying power to the loads, a main power supply line connected to the main power supply, and multiple branch power supply lines connected to the main power supply line. The electrical parameters of the branch power supply lines connected to different locations on the main power supply line are different, and each branch power supply line can be connected to a load that matches its electrical parameters. Compared with the prior art, this invention solves the problem of unequal reference potentials for loads at different locations, separates the load power supply from the control system circuit, adds a filtering circuit, and improves the overall anti-interference capability.

Description

Technical Field

[0001] This invention relates to power supply circuits, and in particular to a multi-load power supply circuit and an air conditioner. Background Technology

[0002] Commercial air conditioners are mainly powered by AC power. With the connection of multiple loads, there will be significant interference, affecting the circuit EMI. Based on the characteristics of the load, the power supply method of the load in the circuit is determined to solve the circuit interference problem.

[0003] Patent No. 201710724831.7 discloses a device with filtering function based on motor control. However, this device only has a motor load, and the patent cannot solve the problem of power supply for multiple loads and the interference of the load on the control system circuit.

[0004] Patent No. 201410515016.6 discloses an anti-interference circuit for a centralized power supply analog high-definition camera. However, this circuit addresses interference to the video output circuit in centralized power supply applications and lacks interference isolation for AC / DC load power supplies when applied to cameras. In practical applications, centralized power supply, used in various fields, can also cause interference to the control system.

[0005] Therefore, how to design a multi-load power supply circuit and air conditioner that can provide individual power to multiple AC and DC loads is a technical problem that the industry urgently needs to solve. Summary of the Invention

[0006] In response to the problem that simultaneous access of multiple loads in the prior art can affect the EMI performance of the circuit, this invention proposes a multi-load power supply circuit and an air conditioner.

[0007] The technical solution of the present invention is to propose a multi-load power supply circuit, including a power supply for supplying power to the load, a main power supply line connected to the power supply, and multiple power supply branches connected to the main power supply line. The electrical parameters of the power supply branches connected to different positions of the main power supply line are different from each other, and each power supply branch can be connected to a load that matches its electrical parameters.

[0008] Furthermore, the main power supply circuit is used to supply power to the switching power supply. A filter module and a first rectifier module are connected in series between the power supply and the switching power supply. The charging voltage of the switching power supply is matched with the output voltage of the first rectifier module.

[0009] Furthermore, the power supply branch includes a first branch for supplying power to the low-interference AC load, and one end of the first branch is connected to the power supply and the filter module for power extraction, and the other end is connected to the low-interference AC load for power supply.

[0010] Furthermore, the power supply branch also includes a second branch for supplying power to the high-interference AC load, and one end of the second branch is connected to the filter module and the first rectifier module for power supply, and the other end is connected to the high-interference AC load for power supply.

[0011] Furthermore, the power supply branch also includes a third branch for supplying power to the high-interference DC load. The third branch includes a second rectifier module with one end connected between the filter module and the first rectifier module, and the other end of the second rectifier module connected to the high-interference DC load for power supply.

[0012] Furthermore, the main power supply circuit includes: fuse FU1, capacitor CX1, capacitor CX2, varistor RV1, discharge resistor R1, rectifier bridge DB1, and common mode inductor T1;

[0013] The first output terminal of the power supply is connected in series with the fuse FU1, the first side of the common mode inductor T1, and the discharge resistor R1, and then connected to the first input terminal of the rectifier bridge DB1. The second output terminal of the power supply is connected in series with the second side of the common mode inductor T1 and then connected to the second input terminal of the rectifier bridge DB1.

[0014] One end of the capacitor CX1 is connected between the fuse FU1 and the common mode inductor T1, and the other end is connected between the second output terminal of the power supply and the common mode inductor T1;

[0015] One end of the capacitor CX2 is connected between the discharge resistor R1 and the common mode inductor T1, and the other end is connected between the second input terminal of the rectifier bridge DB1 and the common mode inductor T1;

[0016] One end of the varistor RV1 is connected between the fuse FU1 and the common mode inductor T1, and the other end is connected between the second output terminal of the power supply and the common mode inductor T1.

[0017] Furthermore, the first branch includes: relay K1 and diode D1;

[0018] The first terminal of the control terminal of the relay K1 is connected to the main control system, and the second terminal is connected to a fixed-level power signal. The first terminal of the controlled terminal of the relay K1 is connected to the main power supply circuit for power extraction, and the other terminal is connected to the low-interference AC load.

[0019] The positive terminal of diode D1 is connected between the control terminal of relay K1 and the main control system, and the negative terminal is connected between the control terminal of relay K1 and the input of the power signal.

[0020] Furthermore, the second branch includes: relay K4 and diode D4;

[0021] The first terminal of the control terminal of the relay K4 is connected to the main control system, and the second terminal is connected to a fixed-level power signal. The first terminal of the controlled terminal of the relay K4 is connected to the main power supply circuit for power extraction, and the other terminal is connected to the high-interference AC load.

[0022] The positive terminal of diode D4 is connected between the control terminal of relay K4 and the main control system, and the negative terminal is connected between the control terminal of relay K4 and the input of the power signal.

[0023] Furthermore, the third branch includes: rectifier bridge DB2, relay K5, and diode D5;

[0024] The first input terminal and the second input terminal of the rectifier bridge DB2 are respectively connected to the main power supply circuit for power extraction. The first output terminal of the rectifier bridge DB2 is connected in series with the controlled terminal of the relay K5 and then connected to the first input terminal of the high interference DC load. The second output terminal of the rectifier bridge DB2 is connected to the second input terminal of the high interference DC load.

[0025] The first terminal of the control terminal of the relay K5 is connected to the main control system, and the second terminal is connected to a fixed-level power signal. The positive terminal of the diode D5 is connected between the control terminal of the relay K5 and the main control system, and the negative terminal is connected between the control terminal of the relay K5 and the power signal input.

[0026] The present invention also proposes an air conditioner having the above-mentioned multi-load power supply circuit.

[0027] Compared with the prior art, the present invention has at least the following beneficial effects:

[0028] This invention adopts a multi-load centralized power supply method, which solves the problem of unequal reference potentials of loads at different locations, separates the load power supply from the control system circuit, adds a filter circuit, and improves the anti-interference capability of the control system circuit. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a system block diagram of the multi-load power supply circuit of the present invention;

[0031] Figure 2 This is a circuit diagram of the multi-load power supply circuit of the present invention. Detailed Implementation

[0032] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0033] Therefore, a feature pointed out in this specification is used to describe one feature of one embodiment of the invention, and does not imply that every embodiment of the invention must have the described feature. Furthermore, it should be noted that this specification describes many features. Although certain features may be combined to illustrate possible system designs, these features may also be used in other combinations not explicitly stated. Therefore, unless otherwise stated, the described combinations are not intended to be limiting.

[0034] The principles and structure of the present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0035] Commercial air conditioners are mainly powered by AC power. With the connection of multiple loads, there will be significant interference, affecting the circuit EMI. The idea of ​​this invention is to propose a multi-load power supply circuit. By designing multiple power supply branches, it solves the problem of unequal reference potentials and poor anti-interference ability when multiple loads are powered.

[0036] The multi-load power supply circuit proposed in this invention includes a power supply for supplying power to the load, a main power supply line connected to the power supply, and multiple main power supply lines connected to the main power supply line.

[0037] The main power supply circuit is used to supply power to the switching power supply, and a filter module and a first rectifier module are connected in series between the power supply and the switching power supply.

[0038] Please see Figure 1 The power supply is POWER, which serves as a 220V AC power input and can power downstream loads. The main power supply circuit consists of a filter module, a rectifier module 1, and one of the switching power supplies connected in sequence to POWER. This main power supply circuit is primarily used to power the switching power supply, which contains multiple low-voltage power outputs for the main control system. The filter module is connected to the output of POWER to filter the power supply and eliminate noise interference. The rectifier module 1 is the first rectifier module, which performs AC / DC conversion, converting the AC power output from the power supply into DC power to charge the switching power supply.

[0039] To provide power to various loads, this invention also includes multiple power supply branches. The specific number of these branches can be adjusted according to actual needs. The multi-load power supply circuit in this invention also needs to supply power to low-interference AC loads, high-interference AC loads, and high-interference DC loads separately. Therefore, this invention provides three power supply branches:

[0040] First branch: Used to supply power to low-interference AC loads. One end of the first branch is connected to the power supply and the filter module to draw power, and the other end is connected to the low-interference AC load for power supply.

[0041] The second branch is used to supply power to the high-interference AC load. One end of the second branch is connected to the power source between the filter module and the first rectifier module, and the other end is connected to the high-interference AC load for power supply.

[0042] The third branch is used to supply power to the high-interference DC load. It includes a second rectifier module with one end connected between the filter module and the first rectifier module, and the other end of the second rectifier module is connected to the high-interference DC load and supplies power to the high-interference DC load.

[0043] Please see Figure 1 The first branch is the one that directs the POWER toward the low-interference AC load. Since the interference generated by this load is low, it can be directly connected to the output of the power supply and will not interfere with the EMI performance of the present invention.

[0044] The second branch is the one from which the filter module faces the high-interference AC load. This part will generate a high interference signal, which may affect the power supply system. Therefore, the present invention connects the high-interference AC load after the filter module, which can ensure the normal operation of the high-interference AC load and will not affect the overall EMI performance of the present invention.

[0045] The third branch is the path from the filter module to the rectifier module 2, which is the second rectifier module mentioned above. Since this branch is mainly used to supply power to high-interference DC loads, and the power supply output is AC, a second rectifier module is needed to convert the AC power output to DC power to supply the high-interference DC load. Furthermore, because the high-interference DC load itself generates significant interference, it is also positioned after the filter module to avoid affecting the overall EMI performance of the invention.

[0046] In other embodiments of the present invention, a fourth branch can be provided, which can be equipped with a third rectifier module. One end of the fourth branch is connected between the POWER and the filter module, and the other end is connected in series with the third rectifier module and then connected to the load. This load is a low-interference DC load. Since it does not generate high interference, it can be directly connected to the output terminal of the power supply. Here, the third rectifier module is also used to perform AC / DC conversion to convert the AC power output by the power supply into DC power for use by the low-interference DC load.

[0047] It should be noted that the first branch, second branch, third branch, and fourth branch mentioned in this invention do not refer to a single branch. The first branch refers to all branches connected between the power supply and the filter module; the second branch refers to all branches connected between the filter module and the first rectifier module; the third branch refers to all branches connected between the filter module and the first rectifier module and connected in series with the second filter module; and the fourth branch refers to all branches connected between the power supply and the filter module and connected in series with the third filter module. In practical applications, the number of the first, second, third, and fourth branches can be selected according to actual needs. As long as they have the same function, they are all classified as the same branch.

[0048] This invention, through the aforementioned configuration, enables flexible matching of low-interference AC loads, low-interference DC loads, high-interference AC loads, and high-interference DC loads, and flexibly realizes power supply between various loads. Compared to the traditional method of directly connecting multiple loads through a single power supply, this design solves the problem of different reference voltages affecting the circuit's EMI performance. In this invention, the electrical parameters in the first, second, third, and fourth branches are different, enabling matching power supply to different loads. Here, electrical parameters refer to the voltage magnitude, current magnitude, and type of electrical signal in the circuit.

[0049] Please see Figure 2 The main power supply circuit proposed in this invention includes: fuse FU1, capacitor CX1, capacitor CX2, varistor RV1, discharge resistor R1, rectifier bridge DB1, and common mode inductor T1;

[0050] The first output terminal of the power supply is connected in series with the fuse FU1, the first side of the common mode inductor T1, and the discharge resistor R1, and then connected to the first input terminal of the rectifier bridge DB1. The second output terminal of the power supply is connected in series with the second side of the common mode inductor T1 and then connected to the second input terminal of the rectifier bridge DB1.

[0051] One end of capacitor CX1 is connected between fuse FU1 and common mode inductor T1, and the other end is connected between the second output terminal of the power supply and common mode inductor T1;

[0052] One end of capacitor CX2 is connected between discharge resistor R1 and common mode inductor T1, and the other end is connected between the second input terminal of rectifier bridge DB1 and common mode inductor T1;

[0053] One end of the varistor RV1 is connected between the fuse FU1 and the common mode inductor T1, and the other end is connected between the second output terminal of the power supply and the common mode inductor T1.

[0054] Please see Figure 2 The power supply is an external power source, with the live and neutral wires input through copper connectors X1 and X2 respectively. The power from connector X1 is output as AC-L (live wire) after passing through fuse FU1, while the power from connector X2 is output as AC-N (neutral wire). The fuse serves as a protection mechanism to prevent burnout caused by excessive current in the circuit. A slow-blow fuse is used here to prevent it from acting on surge currents and avoid false tripping.

[0055] Varistor RV1 has infinite resistance under normal conditions. When overvoltage or lightning strikes occur, exceeding its threshold voltage, its resistance decreases, protecting downstream circuitry. Capacitors CX1 and CX2, acting as X capacitors, are connected in parallel across the input and output terminals of common-mode inductor T1 to filter differential-mode interference. Common-mode inductor T1 primarily filters common-mode interference; through the combined action of capacitors CX1 and CX2, and common-mode inductor T1, interference signals generated in the circuit are filtered out as much as possible. Discharge resistor R1 is used for discharge, outputting power supply M-AC-L to power the downstream circuitry of the filter module.

[0056] Please see Figure 2 The first branch includes: relay K1 and diode D1;

[0057] Among them, one end of the control terminal of relay K1 is connected to the main control system, and the second end is connected to a fixed level power signal. The first end of the controlled terminal of relay K1 is connected to the power supply circuit for power, and the other end is connected to a low interference AC load.

[0058] The positive terminal of diode D1 is connected between the control terminal of relay K1 and the main control system, and the negative terminal is connected between the control terminal of relay K1 and the power signal input.

[0059] VALUE is a low-interference AC load. This invention includes three first branches: VALUE1, VALUE2, and VALUE3. Since the connections within each first branch are identical, only one branch is described above. The three low-interference AC loads are connected to the first branch via copper connectors X3, X4, and X5, respectively, and are connected in parallel to the AC-L terminal of the power network via relays K1, K2, and K3, respectively. The main control system can control signal lines VALUE1, VALUE2, and VALUE3 (here referring to...) respectively. Figure 2 The high and low levels of the VALUE1, VALUE2, and VALUE3 pins in the circuit control the conduction of diodes D1, D2, and D3, which in turn control the opening and closing of relays K1, K2, and K3, thereby replacing manual control of the connection and operation of low-interference AC loads.

[0060] The working principle of the first branch at VALUE1 is explained below. When the pin VALUE1 outputs a high-level signal, its voltage is higher than 12V (i.e., a fixed-level power supply signal). Diode D1 is turned on. At this time, the control terminal of relay K1 is short-circuited, the controlled terminal is in a de-energized state, and the low-interference AC load connected to copper plug X3 is not powered on and does not work.

[0061] When pin VALUE1 outputs a low-level signal, its voltage is below 12V, diode D1 is cut off, the control terminal of relay K1 is activated, the controlled terminal is closed, the low-interference AC load connected to copper plug X3 is powered on and starts working.

[0062] Therefore, by controlling the high and low levels of signal lines VALUE1, VALUE2, and VALUE3, the conduction of diodes D1, D2, and D3 can be controlled, thereby controlling the opening and closing of relays K1, K2, and K3, thus replacing manual control of the connection and operation of low-interference AC loads.

[0063] Please see Figure 2 The second branch includes: relay K4 and diode D4;

[0064] Among them, the first end of the control terminal of relay K4 is connected to the main control system, and the second end is connected to a fixed level power signal. The first end of the controlled terminal of relay K4 is connected to the main power supply circuit for power extraction, and the other end is connected to a high interference AC load.

[0065] The positive terminal of diode D4 is connected between the control terminal of relay K4 and the main control system, and the negative terminal is connected between the control terminal of relay K4 and the power signal input.

[0066] M-AC is a high-interference AC load. Its negative terminal is connected to the neutral wire of the power supply via copper connector X6 and to the live wire of the power supply via copper connector X7. The controlled terminal of relay K4 is connected in series between copper connector X7 and M-AC-L to control whether the high-interference AC load is powered on. The connection of the relay in the second branch is the same as that in the first branch, and its working principle is also similar. By controlling the high and low levels of the M-AC pin, the conduction state of diode D4 is controlled, thereby switching the power-on state of the high-interference AC load and realizing manual control of the connection and operation of load M-AC. This will not be elaborated further.

[0067] Please see Figure 2 The third branch includes: rectifier bridge DB2, relay K5, and diode D5;

[0068] The first and second input terminals of rectifier bridge DB2 are connected to the main power supply circuit for power extraction. The first input terminal of rectifier bridge DB2 is connected in series with the controlled terminal of relay K5 and then connected to the first input terminal of the high-interference DC load. The second output terminal of rectifier bridge DB2 is connected to the second input terminal of the high-interference DC load.

[0069] The first terminal of the control terminal of relay K5 is connected to the main control system, and the second terminal is connected to a fixed-level power signal. The positive terminal of diode D5 is connected between the control terminal of relay K5 and the main control system, and the negative terminal is connected between the control terminal of relay K5 and the power signal input.

[0070] Among them, M-DC is a high-interference DC load. Its positive terminal is the first input terminal mentioned above, which is connected through copper connector X9, and its negative terminal is the second input terminal mentioned above, which is connected through copper connector X8. Since the negative terminal is connected to the neutral line, it can work normally as long as the positive terminal is powered on. The rectifier bridge DB2 is used to convert AC power to DC power and power the high-interference DC load.

[0071] The operating state of the high-interference DC load here is controlled by relay K5. When the controlled terminal of relay K5 is closed, copper connector X9 is energized, and the high-interference DC load is powered on and operates normally. Conversely, when the controlled terminal of relay K5 is open, copper connector X9 is not energized, and the high-interference DC load does not operate. Here, the control of relay K5 is the same as the control method of the relays in the first and second branches. By controlling the high and low levels of the control pin M-DC, the conduction state of diode D5 is controlled, thereby switching the power-on state of the high-interference DC load and realizing manual control of the connection and operation of the load M-DC. This will not be elaborated further here.

[0072] It should be pointed out that, Figure 2 This is only a preferred embodiment of the present invention. In other embodiments of the present invention, the first branch, the second branch, the third branch, and even... Figure 2The number of fourth branches not mentioned herein can be set according to actual needs, and as long as they conform to the control concept of this invention, they should be within the protection scope of this invention.

[0073] The present invention also proposes an air conditioner having the above-mentioned multi-load power supply circuit.

[0074] Compared with the prior art, the present invention adopts a multi-load centralized power supply method, which solves the problem of unequal reference potentials of loads at different locations, separates the load power supply from the control system circuit, adds a filter circuit, and improves the anti-interference capability of the control system circuit.

[0075] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A multi-load power supply circuit, comprising a power supply for supplying power to loads, characterized in that, It also includes a main power supply line connected to the power supply and multiple branch power supply lines connected to the main power supply line. The electrical parameters of the branch power supply lines connected to different positions of the main power supply line are different. Each branch power supply line can be connected to a load that matches its electrical parameters. The main power supply circuit is used to supply power to the switching power supply. A filter module and a first rectifier module are connected in series between the power supply and the switching power supply. The charging voltage of the switching power supply is matched with the output voltage of the first rectifier module. The power supply branch is connected to the power supply and filter module of the main power supply, or the filter module and the first rectifier module, according to the type of load it is connected to and the level of interference. The power supply branch includes a first branch for supplying power to the low-interference AC load, and one end of the first branch is connected to the power supply and the filter module for power extraction, and the other end is connected to the low-interference AC load for power supply. The power supply branch also includes a second branch for supplying power to the high-interference AC load, and one end of the second branch is connected to the filter module and the first rectifier module for power supply, and the other end is connected to the high-interference AC load for power supply. The power supply branch also includes a third branch for supplying power to the high-interference DC load. The third branch includes a second rectifier module with one end connected between the filter module and the first rectifier module, and the other end of the second rectifier module connected to the high-interference DC load for power supply.

2. The multiple load power supply circuit according to claim 1, characterized by The main power supply circuit includes: fuse FU1, capacitor CX1, capacitor CX2, varistor RV1, discharge resistor R1, rectifier bridge DB1, and common mode inductor T1; The first output terminal of the power supply is connected in series with the fuse FU1, the first side of the common mode inductor T1, and the discharge resistor R1, and then connected to the first input terminal of the rectifier bridge DB1. The second output terminal of the power supply is connected in series with the second side of the common mode inductor T1 and then connected to the second input terminal of the rectifier bridge DB1. One end of the capacitor CX1 is connected between the fuse FU1 and the common mode inductor T1, and the other end is connected between the second output terminal of the power supply and the common mode inductor T1; One end of the capacitor CX2 is connected between the discharge resistor R1 and the common mode inductor T1, and the other end is connected between the second input terminal of the rectifier bridge DB1 and the common mode inductor T1; One end of the varistor RV1 is connected between the fuse FU1 and the common mode inductor T1, and the other end is connected between the second output terminal of the power supply and the common mode inductor T1.

3. The multiple load power supply circuit of claim 1, wherein, The first branch includes: relay K1 and diode D1; The first terminal of the control terminal of the relay K1 is connected to the main control system, and the second terminal is connected to a fixed-level power signal. The first terminal of the controlled terminal of the relay K1 is connected to the main power supply circuit for power extraction, and the other terminal is connected to the low-interference AC load. The positive terminal of diode D1 is connected between the control terminal of relay K1 and the main control system, and the negative terminal is connected between the control terminal of relay K1 and the input of the power signal.

4. The multiple load power supply circuit of claim 1, wherein, The second branch includes: relay K4 and diode D4; The first terminal of the control terminal of the relay K4 is connected to the main control system, and the second terminal is connected to a fixed-level power signal. The first terminal of the controlled terminal of the relay K4 is connected to the main power supply circuit for power extraction, and the other terminal is connected to the high-interference AC load. The positive terminal of diode D4 is connected between the control terminal of relay K4 and the main control system, and the negative terminal is connected between the control terminal of relay K4 and the input of the power signal.

5. The multiple load power supply circuit of claim 1, wherein, The third branch includes: rectifier bridge DB2, relay K5, and diode D5; The first input terminal and the second input terminal of the rectifier bridge DB2 are respectively connected to the main power supply circuit for power extraction. The first output terminal of the rectifier bridge DB2 is connected in series with the controlled terminal of the relay K5 and then connected to the first input terminal of the high interference DC load. The second output terminal of the rectifier bridge DB2 is connected to the second input terminal of the high interference DC load. The first terminal of the control terminal of the relay K5 is connected to the main control system, and the second terminal is connected to a fixed-level power signal. The positive terminal of the diode D5 is connected between the control terminal of the relay K5 and the main control system, and the negative terminal is connected between the control terminal of the relay K5 and the power signal input.

6. An air conditioner characterized by The air conditioner has a multi-load power supply circuit as described in any one of claims 1 to 5.

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