CN217282215U

CN217282215U - Circuit for preventing reverse connection of direct current input and direct current air conditioner

Info

Publication number: CN217282215U
Application number: CN202220432217.XU
Authority: CN
Inventors: 张金瑞; 许升; 虞朝丰; 厉杰
Original assignee: Qingdao Haier Smart Technology R&D Co Ltd; Haier Smart Home Co Ltd
Current assignee: Qingdao Haier Smart Technology R&D Co Ltd; Haier Smart Home Co Ltd
Priority date: 2022-03-01
Filing date: 2022-03-01
Publication date: 2022-08-23
Anticipated expiration: 2032-03-01

Abstract

The application relates to the technical field of intelligent household appliances, and discloses a circuit for preventing reverse connection of direct current input, which comprises: the rectifying circuit is connected with the direct-current power supply and is used for normally supplying power when the direct-current power supply is in positive connection and reverse connection; the power polarity detection circuit is connected with the direct-current power supply, and outputs a first level when the direct-current power supply is connected positively and outputs a second level when the direct-current power supply is connected negatively; the communication circuit is used for transmitting information whether the direct-current power supply is connected correctly or not; the intelligent power module is connected with the rectifying circuit; and the microcontroller is connected with the power polarity detection circuit, the communication circuit and the intelligent power module, and is configured to transmit data whether the direct-current power supply is connected correctly to the communication circuit according to the level output by the power polarity detection circuit and control the on/off of the intelligent power module. And prompting when the direct current power supply is reversely connected according to the information transmitted by the communication circuit. The application also discloses a direct current air conditioner.

Description

Circuit for preventing reverse connection of direct current input and direct current air conditioner

Technical Field

The application relates to the technical field of intelligent household appliances, for example to a circuit for preventing reverse connection of direct current input and a direct current air conditioner.

Background

At present, the direct current air conditioner is more and more widely applied by the advantages of wide speed regulation range, low temperature rise, high reliability and the like. Because the direct current air conditioner adopts the direct current power supply to supply power, the problem of positive and negative polarity exists during wiring, and the air conditioner can be damaged once the direct current air conditioner is reversely connected.

The circuit for preventing reverse connection of direct current input in the related art comprises: the control end of the logic control module is connected with the power end of the PWM control chip and used for pulling down the voltage of the power end of the PWM control chip when the direct current input positive end and the direct current input negative end are reversely connected and prompting a user through the light-emitting warning module.

In the process of implementing the embodiments of the present disclosure, it is found that at least the following problems exist in the related art:

the circuit can pull down the voltage of the control chip when the direct-current power supply is reversely connected, so that the control chip is in a turn-off state to protect the circuit, and prompt is carried out through the light-emitting module. However, when the circuit is used for an outdoor unit of an air conditioner, indoor personnel cannot know that the direct current power supply is reversely connected according to the light-emitting warning module.

SUMMERY OF THE UTILITY MODEL

The following presents a simplified summary in order to provide a basic understanding of some aspects of the disclosed embodiments. This summary is not an extensive overview nor is intended to identify key/critical elements or to delineate the scope of such embodiments but rather as a prelude to the more detailed description that is presented later.

The embodiment of the disclosure provides a circuit for preventing reverse connection of direct current input and a direct current air conditioner, so as to prompt when a direct current power supply of an outdoor unit of the air conditioner is reversely connected.

In some embodiments, the circuit for preventing reverse connection of direct current input comprises: the rectifying circuit is connected with the direct-current power supply and is used for normally supplying power when the direct-current power supply is in positive connection and reverse connection; the power polarity detection circuit is connected with the direct-current power supply, and outputs a first level when the direct-current power supply is connected positively and outputs a second level when the direct-current power supply is connected negatively; the communication circuit is used for transmitting information whether the direct-current power supply is connected correctly or not; the intelligent power module is connected with the rectifying circuit; and the microcontroller is connected with the power polarity detection circuit, the communication circuit and the intelligent power module, and is configured to transmit data indicating whether the direct-current power supply is connected correctly to the communication circuit according to the level output by the power polarity detection circuit and control the on/off of the intelligent power module.

Optionally, the rectifier circuit comprises: the anode of the first diode is connected with the anode of the direct current power supply, and the cathode of the first diode is connected with the intelligent power module; the cathode of the second diode is connected with the anode of the first diode, and the anode of the second diode is connected with the intelligent power module and the ground wire; the anode of the third diode is connected with the negative electrode of the direct current power supply, and the cathode of the third diode is connected with the cathode of the first diode; the cathode of the fourth diode is connected with the anode of the third diode, and the anode of the fourth diode is connected with the anode of the second diode; and one end of the first capacitor is connected with the cathode of the first diode, and the other end of the first capacitor is connected with the anode of the second diode.

Optionally, the power polarity detection circuit comprises: the cathode of the input end of the optocoupler is connected with the anode of the direct current power supply, and the emitter of the output end of the optocoupler is connected with the ground wire; one end of the first resistor is connected with the cathode of the input end of the optical coupler, and the other end of the first resistor is connected with the anode of the input end of the optical coupler; one end of the second resistor is connected with the anode of the input end of the optocoupler, and the other end of the second resistor is connected with the cathode of the direct-current power supply; one end of the third resistor is connected with a collector of the output end of the optocoupler, and the other end of the third resistor is connected with a power supply end of the microcontroller; one end of the fourth resistor is connected with a collector of the output end of the optocoupler; and one end of the second capacitor is connected with the other end of the fourth resistor and the microcontroller, and the other end of the second capacitor is connected with the ground wire.

Optionally, the communication circuit and the microcontroller are connected to ground.

Optionally, the method further comprises: the positive pole of the input end of the direct current converter is connected with the negative pole of the first diode, the negative pole of the input end of the direct current converter is connected with the positive pole of the second diode, the positive pole of the first output end of the direct current converter is connected with the third resistor, the communication circuit and the microcontroller, the positive pole of the second output end of the direct current converter is connected with the intelligent power module, and the negative pole of the first output end and the negative pole of the second output end of the direct current converter are connected with the ground wire.

Optionally, the method further comprises: and the power polarity detection circuit is connected with the direct-current power supply through the fault indication circuit.

Optionally, the fault indication circuit comprises: the anode of the light-emitting diode is connected with the cathode of the input end of the optocoupler; the anode of the fifth diode is connected with the cathode of the light-emitting diode, and the cathode of the fifth diode is connected with the anode of the direct-current power supply; and the cathode of the input end of the optocoupler is connected with the anode of the direct-current power supply through the light-emitting diode and the fifth diode.

Optionally, the method further comprises: the electromagnetic compatibility circuit, the rectification circuit and the power polarity detection circuit are connected with the direct-current power supply through the electromagnetic compatibility circuit.

Optionally, the electromagnetic compatibility circuit comprises: one end of the fuse is connected with the positive electrode of the direct-current power supply; the common-mode inductor comprises a first input end, a second input end, a first output end and a second output end, wherein the first input end is connected with the other end of the fuse, the second input end is connected with the negative electrode of the direct-current power supply, the first output end is connected with the anode of the first diode, and the second output end is connected with the anode of the third diode; one end of the fifth resistor is connected with the first input end of the common-mode inductor; one end of the sixth resistor is connected with the other end of the fifth resistor; one end of the discharge tube is connected with the ground, and the other end of the discharge tube is connected with the fifth resistor and the sixth resistor; one end of the seventh resistor is connected with the first output end of the common-mode inductor, and the other end of the seventh resistor is connected with the second output end of the common-mode inductor; one end of the third capacitor is connected with the first output end of the common-mode inductor, and the other end of the third capacitor is connected with the second output end of the common-mode inductor; one end of the fourth capacitor is connected with the first input end of the common-mode inductor, and the other end of the fourth capacitor is connected with the other end of the sixth resistor; one end of the fifth capacitor is connected with the ground, and the other end of the fifth capacitor is connected with the first input end of the common-mode inductor; one end of the sixth capacitor is connected with the ground, and the other end of the sixth capacitor is connected with the second input end of the common-mode inductor; the anode of the first diode is connected with the anode of the direct-current power supply through the first input end and the first output end of the common-mode inductor and the fuse, and the anode of the third diode is connected with the cathode of the direct-current power supply through the second input end and the second output end of the common-mode inductor.

In some embodiments, the direct current air conditioner comprises the circuit for preventing reverse connection of direct current input.

The circuit for preventing reverse connection of direct current input and the direct current air conditioner provided by the embodiment of the disclosure can realize the following technical effects:

after the direct current power supply passes through the rectifying circuit, the communication circuit, the intelligent power module and the microcontroller can work normally no matter the direct current power supply is connected positively or reversely. When the direct current power supply is connected positively, the power supply polarity detection circuit outputs a first level, and the microcontroller sends data that the direct current power supply is connected correctly to the communication circuit. When the direct current power supply is reversely connected, the power supply polarity detection circuit outputs a second level, and the microcontroller sends data of the direct current power supply wiring error to the communication circuit. When the related personnel are near the air conditioner indoor unit, whether the current direct current power supply is correctly wired can be known according to the information transmitted by the communication circuit, so that the prompt can be given when the direct current power supply of the air conditioner outdoor unit is reversely connected.

The foregoing general description and the following description are exemplary and explanatory only and are not restrictive of the application.

Drawings

One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the accompanying drawings and not in limitation thereof, in which elements having the same reference numeral designations are shown as like elements and not in limitation thereof, and wherein:

FIG. 1 is a schematic structural diagram of a circuit for preventing reverse connection of a direct current input according to an embodiment of the present disclosure;

FIG. 2 is a schematic structural diagram of another circuit for preventing reverse connection of DC input according to the embodiment of the present disclosure;

FIG. 3 is a schematic structural diagram of another circuit for preventing reverse connection of DC input according to the embodiment of the present disclosure;

FIG. 4 is a schematic structural diagram of another circuit for preventing reverse connection of DC input according to the embodiment of the present disclosure;

FIG. 5 is a schematic diagram of another circuit for preventing reverse connection of DC input according to the embodiment of the present disclosure;

FIG. 6 is a schematic structural diagram of another circuit for preventing reverse connection of DC input according to the embodiment of the present disclosure;

FIG. 7 is a schematic structural diagram of another circuit for preventing reverse connection of DC input according to the embodiment of the present disclosure;

fig. 8 is a schematic structural diagram of another circuit for preventing reverse connection of a dc input according to an embodiment of the present disclosure.

Reference numerals:

1: a rectifying circuit; 2: a power supply polarity detection circuit; 3: a communication circuit; 4: an intelligent power module; 5: a microcontroller; 6: a DC converter; 7: a fault indication circuit; 8: an electromagnetic compatibility circuit; d1: a first diode; d2: a second diode; d3: a third diode; d4: a fourth diode; d5: a fifth diode; LED: a light emitting diode; PC: an optical coupler; c1: a first capacitor; c2: a second capacitor; c3: a third capacitor; c4: a fourth capacitor; c5: a fifth capacitor; c6: a sixth capacitor; r1: a first resistor; r2: a second resistor; r3: a third resistor; r4: a fourth resistor; r5: a fifth resistor; r6: a sixth resistor; r7: a seventh resistor; f1: a fuse; l1: a common mode inductor; SA 1: a discharge tube; GND: a ground wire; PE: and (4) the earth.

Detailed Description

So that the manner in which the features and elements of the disclosed embodiments can be understood in detail, a more particular description of the disclosed embodiments, briefly summarized above, may be had by reference to the embodiments, some of which are illustrated in the appended drawings. In the following description of the technology, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the disclosed embodiments. However, one or more embodiments may be practiced without these details. In other instances, well-known structures and circuits may be shown for simplicity in the drawings.

The terms "first," "second," and the like in the description and in the claims, and the above-described drawings of embodiments of the present disclosure, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the present disclosure described herein may be made. Furthermore, the terms "comprising" and "having," as well as any variations thereof, are intended to cover non-exclusive inclusions.

In the embodiments of the present disclosure, the terms "upper", "lower", "inner", "middle", "outer", "front", "rear", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings. These terms are used primarily to better describe the disclosed embodiments and their embodiments, and are not used to limit the circuits, elements or components indicated to have a particular orientation or to be constructed and operated in a particular orientation. Moreover, some of the above terms may be used in other meanings besides orientation or positional relationship, for example, the term "upper" may also be used in some cases to indicate a certain attaching or connecting relationship. The specific meanings of these terms in the embodiments of the present disclosure can be understood by those of ordinary skill in the art as appropriate.

In addition, the terms "disposed," "connected," and "secured" are to be construed broadly. For example, "connected" may be a fixed connection, a detachable connection, or a unitary construction; can be a mechanical connection, or an electrical connection; may be directly connected, or indirectly connected through intervening media, or may be in internal communication between two circuits, elements or components. Specific meanings of the above terms in the disclosed embodiments can be understood by those of ordinary skill in the art according to specific situations.

The term "plurality" means two or more, unless otherwise specified.

In the embodiment of the present disclosure, the character "/" indicates that the preceding and following objects are in an or relationship. For example, A/B represents: a or B.

The term "and/or" is an associative relationship that describes objects, meaning that three relationships may exist. For example, a and/or B, represents: a or B, or A and B.

It should be noted that, in the case of no conflict, the embodiments and features in the embodiments of the present disclosure may be combined with each other.

Referring to fig. 1, an embodiment of the present disclosure provides a circuit for preventing reverse connection of a dc input, including a rectification circuit 1, a power polarity detection circuit 2, a communication circuit 3, an intelligent power module 4, and a microcontroller 5. The rectifying circuit 1 is connected with a direct current power supply and used for normally supplying power when the direct current power supply is connected in a positive mode and in a reverse mode. The power polarity detection circuit 2 is connected to the dc power supply, and when the dc power supply is connected, the power polarity detection circuit 2 outputs a first level. When the dc power supply is reversely connected, the power supply polarity detection circuit 2 outputs the second level. The communication circuit 3 is used for transmitting information whether the direct current power supply is correctly wired. The intelligent power module 4 is connected with the rectifying circuit 1. The microcontroller 5 is connected to the power polarity detection circuit 2, the communication circuit 3, and the intelligent power module 4, and configured to transmit data indicating whether the dc power connection is correct to the communication circuit 3 according to the level output by the power polarity detection circuit 2, and control on/off of the intelligent power module 4.

By adopting the circuit for preventing reverse connection of direct current input, after a direct current power supply passes through the rectifying circuit, the communication circuit, the intelligent power module and the microcontroller can work normally no matter the direct current power supply is connected positively or reversely. When the direct current power supply is connected positively, the power supply polarity detection circuit outputs a first level, and the microcontroller sends data that the direct current power supply is connected correctly to the communication circuit. When the direct current power supply is reversely connected, the power supply polarity detection circuit outputs a second level, and the microcontroller sends data of the direct current power supply wiring error to the communication circuit. When the related personnel are near the air conditioner indoor unit, whether the current direct current power supply is correctly connected can be known according to the information transmitted by the communication circuit, so that prompt is given when the direct current power supply of the air conditioner outdoor unit is reversely connected.

The model number of the microcontroller 5 may be PIC16F1824, or AT89S 51.

The communication circuit 3 comprises a digital carrier communication coding and decoding chip and peripheral circuits thereof. The first data end is connected with the data end of the microcontroller 5, the second data end is connected with the communication circuit of the indoor unit of the air conditioner, and the power supply end is connected with the power supply end of the microcontroller 5. The data terminals of the microcontroller 5 are a data transmitting terminal and a data receiving terminal. The structure of the communication circuit 3 is related to the type of the digital carrier communication coding and decoding chip, and can be designed according to a data manual with corresponding type, which belongs to the prior art and is not described any more. Therefore, data can be transmitted through the connecting line of the communication circuit, and signal transmission failure caused by long distance between the indoor unit and the outdoor unit of the air conditioner is avoided.

The model of the digital carrier communication coding and decoding chip can be XL1192S, or XL1192E 1.

As shown in fig. 2, optionally, the rectifier circuit 1 includes a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, and a first capacitor C1. The anode of the first diode D1 is connected to the positive terminal of the dc power supply, and the cathode is connected to the smart power module 4. The cathode of the second diode D2 is connected to the anode of the first diode D1, and the anode is connected to the smart power module 4 and the ground GND. The anode of the third diode D3 is connected to the cathode of the dc power supply, and the cathode is connected to the cathode of the first diode D1. The cathode of the fourth diode D4 is connected to the anode of the third diode D3, and the anode is connected to the anode of the second diode D2. One end of the first capacitor C1 is connected to the cathode of the first diode D1, and the other end is connected to the anode of the second diode D2. Therefore, the rectifier circuit is simple in structure and low in cost, and can realize voltage stabilization.

In order to improve the voltage stability of the rectified dc power, two capacitors may be connected in parallel as the first capacitor C1.

Optionally, the power polarity detection circuit 2 includes an optocoupler PC, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, and a second capacitor C2. The cathode of the input end of the optocoupler PC is connected with the anode of the direct-current power supply, and the emitter of the output end of the optocoupler PC is connected with the ground wire GND. One end of the first resistor R1 is connected with the cathode of the input end of the optical coupler PC, and the other end of the first resistor R1 is connected with the anode of the input end of the optical coupler PC. One end of the second resistor R2 is connected with the anode of the input end of the optocoupler PC, and the other end of the second resistor R2 is connected with the cathode of the direct-current power supply. One end of the third resistor R3 is connected with the collector of the output terminal of the optocoupler PC, and the other end is connected with the power supply terminal of the microcontroller 5. One end of the fourth resistor R4 is connected to the collector of the output terminal of the optocoupler PC. One end of the second capacitor C2 is connected to the other end of the fourth resistor R4 and the microcontroller 5, and the other end is connected to the ground GND. When the dc power supply is connected, the optocoupler PC is not turned on, and the microcontroller 5 receives a high level (first level). And the microcontroller 5 determines that the direct-current power supply is connected positively according to the received high level, and controls the intelligent power module 4 to be conducted. When the dc power supply is reversely connected, the optocoupler PC is turned on, and the microcontroller 5 receives a low level (second level). The microcontroller 5 determines the reverse connection of the direct current power supply according to the received low level, and controls the intelligent power module 4 to be disconnected. Thus, the stability of the power polarity circuit is high, and different levels can be output to the microcontroller when the direct current power supply is connected in a positive/negative mode.

Since the voltage across the second resistor R2 is high, two resistors in series can be used as the second resistor R2 to prevent the resistors from being damaged.

Alternatively, the ground terminals of the communication circuit 3 and the microcontroller 5 are connected to the ground GND. Therefore, data transmission can be carried out between the communication circuit and the microcontroller, and the same power supply is adopted for power supply.

Optionally, the circuit for preventing reverse connection of the direct current input further includes a direct current converter 6, an anode of the input end is connected to a cathode of a first diode D1, a cathode of the input end is connected to an anode of a second diode D2, an anode of the first output end is connected to a third resistor R3, a power supply terminal of the communication circuit 3 and a power supply terminal of the microcontroller 5, an anode of the second output end is connected to the intelligent power module 4, and a cathode of the first output end and a cathode of the second output end are connected to a ground GND. The negative poles of the input, the first output and the second output of the dc converter 6 are connected internally, schematically indicated by a single line in the figure. Therefore, the voltage of the direct-current power supply can be stably reduced by the direct-current converter, and the power supply of the communication circuit, the intelligent power module and the microcontroller is stable.

The dc converter 6 has two outputs for powering the communication circuit 3, the intelligent power module 4 and the microcontroller 5. The output voltage of the first output terminal is 5V, and the output voltage of the second output terminal is 15V.

Referring to fig. 3, another circuit for preventing reverse connection of dc input is provided in the embodiments of the present disclosure, and includes a rectification circuit 1, a power polarity detection circuit 2, a communication circuit 3, an intelligent power module 4, a microcontroller 5, and a fault indication circuit 7. The rectifying circuit 1 is connected with a direct current power supply and used for normally supplying power when the direct current power supply is connected in a positive mode and in a reverse mode. The power polarity detection circuit 2 is connected to the dc power supply, and when the dc power supply is connected, the power polarity detection circuit 2 outputs a first level. When the dc power supply is reversely connected, the power supply polarity detection circuit 2 outputs the second level. The communication circuit 3 is used for transmitting information whether the direct current power supply is correctly wired. The intelligent power module 4 is connected with the rectifying circuit 1. The microcontroller 5 is connected to the power polarity detection circuit 2, the communication circuit 3, and the intelligent power module 4, and configured to transmit data indicating whether the dc power connection is correct to the communication circuit 3 according to the level output by the power polarity detection circuit 2, and control on/off of the intelligent power module 4. The power polarity detection circuit 2 is connected to a dc power supply via a fault indication circuit 7.

By adopting the circuit for preventing reverse connection of direct current input, when a maintenance person maintains the air conditioner, whether the direct current power supply is reversely connected can be determined through the fault indication circuit of the outdoor unit, and the direct current power supply does not need to go in and out of a room to be determined. The time for entering and exiting the room is saved, and the efficiency of maintenance personnel for maintaining the air conditioner is improved.

As shown in connection with fig. 4, optionally, the fault indication circuit 7 comprises a light emitting diode LED and a fifth diode D5. And the anode of the light emitting diode LED is connected with the cathode of the input end of the optocoupler PC. The anode of the fifth diode D5 is connected to the cathode of the light emitting diode LED, and the cathode is connected to the anode of the dc power supply. Unlike the above-described embodiment, the cathode of the input terminal of the optocoupler PC is not directly connected to the positive electrode of the dc power supply, but is connected to the positive electrode of the dc power supply through the light emitting diode LED and the fifth diode D5. When the direct current power supply is connected in the positive direction, because the fifth diode is in a reverse cut-off state, current cannot flow through the light-emitting diode, and the light-emitting diode is in a turn-off state. When the direct current power supply is reversely connected, the current flows through the light emitting diode to enable the light emitting diode to be in a bright state because the fifth diode is in a conducting state. Therefore, related personnel determine whether the direct-current power supply is reversely connected according to the state of the light-emitting diode, the checking mode is simple, and the time for determining the fault is saved.

Referring to fig. 5, another circuit for preventing reverse connection of dc input is provided in the embodiments of the present disclosure, and includes a rectification circuit 1, a power polarity detection circuit 2, a communication circuit 3, an intelligent power module 4, a microcontroller 5, and an electromagnetic compatibility circuit 8. The rectifying circuit 1 is connected with a direct current power supply and used for normally supplying power when the direct current power supply is connected in a positive mode and in a reverse mode. The power polarity detection circuit 2 is connected to the dc power supply, and when the dc power supply is connected, the power polarity detection circuit 2 outputs a first level. When the dc power supply is reversely connected, the power supply polarity detection circuit 2 outputs the second level. The communication circuit 3 is used for transmitting information whether the direct current power supply is correctly wired. The intelligent power module 4 is connected with the rectifying circuit 1. The microcontroller 5 is connected to the power polarity detection circuit 2, the communication circuit 3, and the intelligent power module 4, and is configured to transmit data indicating whether the dc power connection is correct to the communication circuit 3 according to the level output by the power polarity detection circuit 2, and to control on/off of the intelligent power module 4. The rectifying circuit 1 and the power supply polarity detection circuit 2 are connected to a direct current power supply through an electromagnetic compatibility circuit 8.

By adopting the circuit for preventing reverse connection of direct current input, which is provided by the embodiment of the disclosure, through adding the electromagnetic compatibility circuit, the electromagnetic interference of power supply is reduced, and the damage of components in the circuit is prevented.

Optionally, the electromagnetic compatibility circuit 8 includes a fuse F1, a common mode inductor L1, a fifth resistor R5, a sixth resistor R6, a discharge tube SA1, a seventh resistor R7, a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5, and a sixth capacitor C6. One end of the fuse F1 is connected to the positive electrode of the dc power supply. The common mode inductor L1 includes a first input terminal, a second input terminal, a first output terminal, and a second output terminal, the first input terminal is connected to the other end of the fuse F1, the second input terminal is connected to the negative electrode of the dc power supply, the first output terminal is connected to the anode of the first diode D1, and the second output terminal is connected to the anode of the third diode D3. One end of the fifth resistor R5 is connected to the first input terminal of the common mode inductor L1. One end of the sixth resistor R6 is connected to the other end of the fifth resistor R5. Discharge tube SA1 has one end connected to ground PE and the other end connected to fifth resistor R5 and sixth resistor R6. One end of the seventh resistor R7 is connected to the first output terminal of the common mode inductor L1, and the other end is connected to the second output terminal of the common mode inductor L1. One end of the third capacitor C3 is connected to the first output terminal of the common mode inductor L1, and the other end is connected to the second output terminal of the common mode inductor L1. One end of the fourth capacitor C4 is connected to the first input terminal of the common mode inductor L1, and the other end is connected to the other end of the sixth resistor R6. One end of the fifth capacitor C5 is connected to ground PE, and the other end is connected to the first input terminal of the common mode inductor L1. One end of the sixth capacitor C6 is connected to the ground PE, and the other end is connected to the second input terminal of the common mode inductor L1. Unlike the above embodiments, the anode of the first diode D1 is not directly connected to the positive electrode of the dc power source, but is connected to the positive electrode of the dc power source through the first input terminal and the first output terminal of the common mode inductor L1 and the fuse F1. The anode of the third diode D3 is not directly connected to the negative terminal of the dc power source, but is connected to the negative terminal of the dc power source through the second input terminal and the second output terminal of the common mode inductor L1. The common-mode inductor L1 and the corresponding capacitor are used for filtering electromagnetic interference of the direct-current air conditioner, and the discharge tube SA1 and the corresponding capacitor are used for preventing external lightning stroke damage. Therefore, the electromagnetic compatibility circuit is simple in structure, electromagnetic interference of power supply can be reduced, and damage to components in the circuit is prevented.

With reference to fig. 7 and 8, another circuit for preventing reverse connection of dc input is provided in the embodiments of the present disclosure, and includes a rectification circuit 1, a power polarity detection circuit 2, a communication circuit 3, an intelligent power module 4, a microcontroller 5, a fault indication circuit 7, and an electromagnetic compatibility circuit 8. The rectifying circuit 1 is connected with a direct current power supply and used for normally supplying power when the direct current power supply is connected in a positive mode and in a reverse mode. The power polarity detection circuit 2 is connected to the dc power supply, and when the dc power supply is connected, the power polarity detection circuit 2 outputs a first level. When the dc power supply is reversely connected, the power supply polarity detection circuit 2 outputs the second level. The communication circuit 3 is used for transmitting information whether the direct current power supply is correctly wired. The intelligent power module 4 is connected with the rectification circuit 1. The microcontroller 5 is connected to the power polarity detection circuit 2, the communication circuit 3, and the intelligent power module 4, and configured to transmit data indicating whether the dc power connection is correct to the communication circuit 3 according to the level output by the power polarity detection circuit 2, and control on/off of the intelligent power module 4. The power polarity detection circuit 2 and the fault indication circuit 7 are connected with a direct current power supply through an electromagnetic compatibility circuit 8, and the rectification circuit 1 is connected with the direct current power supply through the electromagnetic compatibility circuit 8.

By adopting the circuit for preventing reverse connection of direct current input, which is provided by the embodiment of the disclosure, on one hand, the information of direct current power supply wiring can be obtained through the fault indication circuit, and on the other hand, the damage of components in the circuit can be prevented through the electromagnetic compatibility circuit.

The embodiment of the disclosure provides a direct current air conditioner, which comprises a circuit for preventing reverse connection of direct current input, provided by any embodiment. When the related personnel are near the indoor unit, the related personnel can know whether the current direct current power supply is correctly connected according to the information transmitted by the communication circuit so as to prompt when the direct current power supply of the outdoor unit is reversely connected. The embodiment of the utility model provides a direct current air conditioner includes the circuit that is used for direct current input to prevent reverse connection in the above-mentioned embodiment, consequently the embodiment of the utility model provides a direct current air conditioner also possesses the beneficial effect that describes in the above-mentioned embodiment.

The above description and the drawings sufficiently illustrate embodiments of the disclosure to enable those skilled in the art to practice them. Other embodiments may include structural and other changes. The examples merely typify possible variations. Individual components and functions are optional unless explicitly required, and the sequence of operations may vary. Portions and features of some embodiments may be included in or substituted for those of others. The embodiments of the present disclosure are not limited to the structures that have been described above and shown in the drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A circuit for preventing reverse connection of a dc input, comprising:

the rectifying circuit (1) is connected with the direct-current power supply and is used for normally supplying power when the direct-current power supply is in positive connection and reverse connection;

the power polarity detection circuit (2) is connected with the direct-current power supply, when the direct-current power supply is connected positively, the power polarity detection circuit (2) outputs a first level, and when the direct-current power supply is connected reversely, the power polarity detection circuit (2) outputs a second level;

a communication circuit (3) for transmitting information on whether the DC power supply is correctly wired;

the intelligent power module (4) is connected with the rectifying circuit (1);

and the microcontroller (5) is connected with the power polarity detection circuit (2), the communication circuit (3) and the intelligent power module (4), and is configured to transmit data whether the direct-current power supply is connected correctly to the communication circuit (3) according to the level output by the power polarity detection circuit (2) and control the on/off of the intelligent power module (4).

2. A circuit according to claim 1, characterized in that the rectifier circuit (1) comprises:

a first diode (D1), the anode of which is connected with the anode of the direct current power supply, and the cathode of which is connected with the intelligent power module (4);

a second diode (D2), the cathode of which is connected with the anode of the first diode (D1), and the anode of which is connected with the intelligent power module (4) and the ground wire (GND);

a third diode (D3), the anode of which is connected with the cathode of the DC power supply, and the cathode of which is connected with the cathode of the first diode (D1);

a fourth diode (D4) having a cathode connected to the anode of the third diode (D3) and an anode connected to the anode of the second diode (D2);

and a first capacitor (C1) having one end connected to the cathode of the first diode (D1) and the other end connected to the anode of the second diode (D2).

3. A circuit according to claim 2, characterized in that the supply polarity detection circuit (2) comprises:

the cathode of the input end of the optical coupler (PC) is connected with the anode of the direct-current power supply, and the emitter of the output end of the optical coupler (PC) is connected with the ground wire (GND);

one end of the first resistor (R1) is connected with the cathode of the input end of the optical coupler (PC), and the other end of the first resistor (R1) is connected with the anode of the input end of the optical coupler (PC);

one end of the second resistor (R2) is connected with the anode of the input end of the optical coupler (PC), and the other end of the second resistor (R2) is connected with the cathode of the direct-current power supply;

one end of the third resistor (R3) is connected with a collector of the output end of the optocoupler (PC), and the other end of the third resistor is connected with a power supply end of the microcontroller (5);

a fourth resistor (R4), one end of which is connected to the collector of the output terminal of the optocoupler (PC);

and one end of the second capacitor (C2) is connected with the other end of the fourth resistor (R4) and the microcontroller (5), and the other end of the second capacitor is connected with the ground wire (GND).

4. A circuit as claimed in claim 1, characterized in that the communication circuit (3) and the microcontroller (5) are connected to Ground (GND).

5. The circuit of claim 3, further comprising:

the direct current converter (6) is characterized in that the anode of the input end is connected with the cathode of the first diode (D1), the cathode of the input end is connected with the anode of the second diode (D2), the anode of the first output end is connected with the third resistor (R3), the communication circuit (3) and the microcontroller (5), the anode of the second output end is connected with the intelligent power module (4), and the cathode of the first output end and the cathode of the second output end are connected with the ground wire (GND).

6. The circuit of claim 3, further comprising:

and the fault indication circuit (7) and the power polarity detection circuit (2) are connected with the direct-current power supply through the fault indication circuit (7).

7. The circuit according to claim 6, characterized in that the fault indication circuit (7) comprises:

a Light Emitting Diode (LED), an anode of which is connected with a cathode of an input end of the optical coupler (PC);

a fifth diode (D5) having an anode connected to the cathode of the Light Emitting Diode (LED) and a cathode connected to the anode of the DC power supply;

wherein, the cathode of the input end of the optical coupler (PC) is connected with the anode of the direct current power supply through a Light Emitting Diode (LED) and a fifth diode (D5).

8. The circuit of any of claims 2 to 7, further comprising:

the electromagnetic compatibility circuit (8), the rectification circuit (1) and the power polarity detection circuit (2) are connected with a direct current power supply through the electromagnetic compatibility circuit (8).

9. The circuit according to claim 8, characterized in that the electromagnetic compatibility circuit (8) comprises:

a fuse (F1) having one end connected to the positive electrode of the DC power supply;

the common-mode inductor (L1) comprises a first input end, a second input end, a first output end and a second output end, wherein the first input end is connected with the other end of the fuse (F1), the second input end is connected with the negative electrode of the direct-current power supply, the first output end is connected with the anode of the first diode (D1), and the second output end is connected with the anode of the third diode (D3);

a fifth resistor (R5) having one end connected to the first input terminal of the common mode inductor (L1);

a sixth resistor (R6) having one end connected to the other end of the fifth resistor (R5);

a discharge tube (SA1) having one end connected to ground (PE) and the other end connected to a fifth resistor (R5) and a sixth resistor (R6);

a seventh resistor (R7), one end of which is connected with the first output end of the common mode inductor (L1), and the other end of which is connected with the second output end of the common mode inductor (L1);

a third capacitor (C3), one end of which is connected with the first output end of the common mode inductor (L1), and the other end of which is connected with the second output end of the common mode inductor (L1);

a fourth capacitor (C4), one end of which is connected with the first input end of the common mode inductor (L1), and the other end of which is connected with the other end of the sixth resistor (R6);

a fifth capacitor (C5) having one end connected to ground (PE) and the other end connected to the first input terminal of the common mode inductor (L1);

a sixth capacitor (C6) having one end connected to ground (PE) and the other end connected to the second input terminal of the common mode inductor (L1);

the anode of the first diode (D1) is connected with the anode of the direct current power supply through the first input end and the first output end of the common-mode inductor (L1) and the fuse (F1), and the anode of the third diode (D3) is connected with the cathode of the direct current power supply through the second input end and the second output end of the common-mode inductor (L1).

10. A dc air conditioner characterized by comprising the circuit for preventing reverse connection of dc input according to any one of claims 1 to 9.