CN214429255U - Wiring protection circuit, device and household appliance - Google Patents

Abstract

The application discloses a wiring protection circuit, a device and a household appliance, wherein the circuit comprises a detection circuit, and the detection circuit detects the wiring state of a wiring circuit; the wiring circuit includes: the three-phase four-wire power supply circuit comprises a three-phase four-wire power supply circuit, a rectifying circuit and a load circuit; two input ends of the rectification circuit are connected with two output ends of the three-phase four-wire power supply circuit; two output ends of the rectifying circuit are connected with two input ends of the load circuit; the rectifying circuit is used for rectifying the output voltage of the three-phase four-wire power supply circuit and supplying the rectified voltage to the load circuit; the detection circuit collects rectified voltage and detects whether the rectified voltage meets a preset working voltage condition; and if not, determining the wiring fault and executing the protection operation of the wiring circuit. Therefore, whether the rectified voltage is overvoltage or not is detected through the detection circuit, the wiring state of the wiring circuit is determined, namely, the wiring is correct or wrong, whether the protection operation of the wiring circuit is executed or not is determined according to the wiring state, the protection of components in the whole circuit is achieved, and the fire disaster is avoided.

Description

Wiring protection circuit, device and household appliance

Technical Field

The application relates to the electronic technology, in particular to a wiring protection circuit, a wiring protection device and a household appliance.

Background

At present, an air conditioner outdoor unit is connected with the air conditioner outdoor unit in a three-phase four-wire connection mode, input voltages are respectively provided to two input ends of a rectifying circuit in the air conditioner outdoor unit by utilizing a live wire and a zero wire of any phase of three phases, and the voltages rectified by the rectifying circuit supply power circuits, a fan driving circuit and other circuits, so that the air conditioner outdoor unit works and then starts the indoor unit.

However, because current three-phase four-wire connection does not prevent slow-witted design, the position that connects the zero line connects into the live wire, and the input voltage of two input ends of rectifier circuit provides through the live wire respectively promptly, leads to the voltage after the rectification too high, causes the damage of components and parts such as switching power supply chip, probably breaks out fire when serious.

SUMMERY OF THE UTILITY MODEL

In order to solve the technical problem, the application provides a wiring protection circuit, a wiring protection device and a household appliance.

The technical scheme of the application is realized as follows:

in a first aspect, a wiring protection circuit is provided, which includes a detection circuit for detecting a wiring state of the wiring circuit; wherein the content of the first and second substances,

the wiring circuit includes: the three-phase four-wire power supply circuit comprises a three-phase four-wire power supply circuit, a rectifying circuit and a load circuit; two input ends of the rectification circuit are connected with two output ends of the three-phase four-wire power supply circuit; two output ends of the rectifying circuit are connected with two input ends of the load circuit; the rectifying circuit is used for rectifying the voltage output by the three-phase four-wire power supply circuit and providing the rectified voltage for the load circuit;

the detection circuit is used for collecting rectified voltage of the rectifying circuit and detecting whether the rectified voltage meets a preset working voltage condition; and if the preset working voltage condition is not met, determining a wiring fault and executing the protection operation of the wiring circuit.

In the above scheme, if the preset working voltage condition is met, it is determined that the wiring is normal, and the wiring circuit is controlled to work normally.

In the scheme, the normal connection represents that two input ends of the rectification circuit are respectively connected with a live wire and a zero wire of the three-phase four-wire power supply circuit; and the wiring fault representation indicates that two input ends of the rectification circuit are connected with a live wire of the three-phase four-wire power circuit.

In the above scheme, the preset operating voltage condition is: the rectified voltage is within a preset voltage range.

In the above scheme, the detection circuit includes: the circuit comprises a voltage comparator, a first resistor, a second resistor, a third resistor, a fourth resistor and a first capacitor; the positive input end of the voltage comparator is connected with the first output end of the rectifying circuit through the first resistor and is grounded through the second resistor; the first capacitor is connected in parallel to two ends of the second resistor; the negative input end of the voltage comparator is connected with a first voltage source through the third resistor and is grounded through the fourth resistor; the output end of the voltage comparator is connected with the microcontroller, so that the microcontroller collects the comparison result of the voltage comparator and controls the execution unit to execute the protection operation of the wiring circuit corresponding to the comparison result based on the comparison result.

In the above scheme, the execution unit is an information output unit, and the microcontroller is specifically configured to control the information output unit to output the wiring prompt information based on the comparison result, so as to prompt whether wiring is correct.

In the above solution, the wiring protection circuit further includes: an optocoupler circuit; the detection circuit is connected with the microcontroller through the optocoupler circuit; the optical coupling circuit is used for isolating the output end of the detection circuit from the microcontroller.

In the above scheme, the optical coupling circuit includes: an optical coupler and a fifth resistor; the optical coupler consists of a light-emitting diode and a phototriode; the output end of the detection circuit is connected with the anode of the light-emitting diode, and the cathode of the light-emitting diode is grounded; the positive electrode of a photosensitive triode in the optical coupler is connected with a second voltage source, and the negative electrode of the photosensitive triode is grounded through the fifth resistor; the optical coupling circuit further includes: a second capacitor and a third capacitor; one end of the second capacitor is connected with the second voltage source, and the other end of the second capacitor is grounded; the third capacitor is connected in parallel with two ends of the light-emitting diode; the optical coupling circuit further includes: a sixth resistor and a fourth capacitor; and the cathode of the photosensitive diode is grounded after being connected in series with the fourth capacitor through the sixth resistor.

In the above solution, the wiring protection circuit further includes: a seventh resistor and an eighth resistor; one end of the seventh resistor is connected with the first voltage source; the other end of the seventh resistor is connected with the output end of the detection circuit and is also connected with the input end of the optical coupling circuit through the eighth resistor.

In the above solution, the wiring protection circuit further includes: a first protection circuit; the first protection circuit is used for controlling a switching power supply of the load circuit to be in a closed state and stopping supplying power to the load circuit when the wiring circuit has a wiring fault.

In the above solution, the wiring protection circuit further includes: a second protection circuit; the second protection circuit includes: at least one electrolytic capacitor; the at least one electrolytic capacitor is connected in series and then connected in parallel to two output ends of the rectifying circuit; wherein, the withstand voltage value of the at least one electrolytic capacitor after being connected in series is larger than the withstand voltage threshold value.

In a third aspect, a wiring protection circuit is provided, which includes a wiring circuit and a first protection circuit; the wiring circuit includes: the three-phase four-wire power supply circuit comprises a three-phase four-wire power supply circuit, a rectifying circuit and a load circuit; two input ends of the rectification circuit are connected with two output ends of the three-phase four-wire power supply circuit; two output ends of the rectifying circuit are connected with two input ends of the load circuit; the rectifying circuit is used for rectifying the voltage output by the three-phase four-wire power supply circuit and providing the rectified voltage for the load circuit; the first protection circuit is used for controlling a switching power supply of the load circuit to be in a closed state and stopping supplying power to the load circuit when the wiring circuit has wiring faults.

In the above solution, the wiring protection circuit further includes: a second protection circuit; the second protection circuit includes: at least one electrolytic capacitor; the at least one electrolytic capacitor is connected in series and then connected in parallel to two output ends of the rectifying circuit; wherein, the withstand voltage value of the at least one electrolytic capacitor after being connected in series is larger than the withstand voltage threshold value.

In a third aspect, a wiring protection device is provided, which comprises any one of the wiring protection circuits in the above aspects.

In a fourth aspect, a household appliance is provided, which comprises the wiring protection circuit and the wiring circuit in any one of the above aspects.

The application discloses a wiring protection circuit, which comprises a detection circuit, a control circuit and a control circuit, wherein the detection circuit is used for detecting the wiring state of the wiring circuit; wherein, wiring circuit includes: the three-phase four-wire power supply circuit comprises a three-phase four-wire power supply circuit, a rectifying circuit and a load circuit; two input ends of the rectification circuit are connected with two output ends of the three-phase four-wire power supply circuit; two output ends of the rectifying circuit are connected with two input ends of the load circuit and also connected with two input ends of the detection circuit; the rectifying circuit is used for rectifying the voltage output by the three-phase four-wire power supply circuit and providing the rectified voltage for the load circuit; the detection circuit is used for acquiring rectified voltage of the rectifying circuit and detecting whether the rectified voltage meets a preset working voltage condition; and if the preset working voltage condition is not met, determining a wiring fault and executing protection operation of the wiring circuit. Therefore, whether the rectified voltage is overvoltage or not is detected through the detection circuit, the wiring state of the wiring circuit is determined, namely, the wiring is correct or wrong, whether the protection operation of the wiring circuit is executed or not is determined according to the wiring state, the protection of components in the whole circuit is achieved, and the fire disaster is avoided.

Drawings

FIG. 1 is a schematic diagram of a first component structure of a wiring protection circuit in an embodiment of the present application;

FIG. 2 is a schematic diagram of a second component structure of the wiring protection circuit in the embodiment of the present application;

FIG. 3 is a schematic flow chart illustrating a wire connection determination method according to an embodiment of the present application;

FIG. 4 is a third schematic structural diagram of the wiring protection circuit in the embodiment of the present application;

FIG. 5 is a fourth schematic structural diagram of a wiring protection circuit according to an embodiment of the present disclosure;

FIG. 6 is a schematic diagram of a fifth component structure of the wiring protection circuit in the embodiment of the present application;

fig. 7 is a schematic diagram of a sixth structure of the connection protection circuit in the embodiment of the present application.

Detailed Description

So that the manner in which the features and elements of the present embodiments can be understood in detail, a more particular description of the embodiments, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings.

Fig. 1 is a schematic diagram of a first composition structure of the wiring protection circuit in the embodiment of the present application, and as shown in fig. 1, the wiring protection circuit 10 includes a detection circuit 101; the detection circuit 101 is used for detecting the wiring state of the wiring circuit 11;

wherein the wiring circuit 11 includes: a three-phase four-wire power supply circuit 110, a rectifier circuit 111, and a load circuit 112; two input ends of the rectifying circuit 111 are connected with two output ends of the three-phase four-wire power supply circuit 110; two output ends of the rectifying circuit 111 are connected with two input ends of the load circuit 112;

the rectifying circuit 111 is configured to rectify the voltage output by the three-phase four-wire power supply circuit 110, and provide the rectified voltage to the load circuit 112;

the detection circuit 101 is configured to collect rectified voltage of the rectification circuit 111, and detect whether the rectified voltage meets a preset working voltage condition; and if the preset working voltage condition is not met, determining that the wiring fails, and executing protection operation of the wiring circuit 11.

It should be noted that, this application has designed a wiring protection circuit in order to avoid adopting the condition that the position misconnection that connects the zero line when three-phase four-wire connection mode is worked a telephone switchboard the built-in rectifier circuit of outdoor machine of air-conditioner leads to component damage in the whole circuit for the live wire, this wiring protection circuit includes detection circuit, and detection circuit is used for detecting the wiring state, and then confirms whether to carry out wiring circuit protection operation according to the wiring state to reach the protection to component in the whole circuit, and avoid taking place the conflagration.

Here, when the two input terminals of the rectifying circuit are connected to the live line and the neutral line of the three-phase four-wire power supply circuit, respectively, it indicates that the wiring is normal. When two input ends of the rectification circuit are connected with a live wire of the three-phase four-wire power circuit, a wiring fault is indicated.

Specifically, the detection circuit detects whether the wiring is correct or not by determining the voltage rectified by the rectifier circuit. Specifically, if the rectified voltage meets the preset working voltage condition, the wiring is correct, and the rectified voltage can directly provide voltage for circuits such as a switching power supply circuit, a fan driving circuit and the like, so that the air conditioner outdoor unit works and then starts the indoor unit. If the rectified voltage does not meet the preset working voltage condition, the wiring is wrong, the wiring mode is modified, and the detection is carried out again until the rectified voltage meets the preset working voltage condition, namely, the wiring is correct.

The above mentioned preset operating voltage conditions are: the rectified voltage is within a preset voltage range.

Here, the preset voltage range may be understood as a rectified voltage range when the wiring circuit normally operates. That is, the rectified voltage is within a preset voltage range, which indicates that the preset working voltage condition is met, i.e., the wiring circuit works normally; the rectified voltage is outside the preset voltage range, which indicates that the preset working voltage condition is not met, namely the wiring circuit works abnormally.

It should be noted that the wiring protection circuit and the wiring circuit mentioned above may form a complete circuit and be disposed in the same electronic device; or the wiring protection circuit and the wiring circuit are separately arranged in two household appliances, wherein the household appliance with the built-in wiring protection circuit is used for detecting the appliances with the built-in wiring circuit and detecting whether the wiring is correct or not.

It should be noted that other matching elements, such as one or more combinations of capacitors, comparators, and resistors, may be included in the detection circuit. The detection circuit of one or a plurality of components and parts combination is used for detecting the wiring state, and then whether the protection operation of the wiring circuit is executed or not is determined according to the wiring state, so that the protection of the components and parts in the whole circuit is realized.

Based on the foregoing embodiments, a specific circuit structure diagram is provided in the present application, and fig. 2 is a schematic diagram of a second component structure of the wiring protection circuit in the embodiments of the present application.

As shown in fig. 2, the wiring protection circuit 10 includes a detection circuit 101, and one input terminal of the detection circuit 101 is connected to the output terminal 4 of the rectification circuit 111, and the other input terminal is connected to the output terminal 1 (i.e., ground terminal) of the rectification circuit 111.

The detection circuit 101 may specifically include: the voltage comparator Q, first resistance R1, second resistance R2, third resistance R3, fourth resistance R4, resistance R9, resistance R10 and electric capacity C5. Wherein, Q comprises two voltage comparators.

The concrete connection mode is as follows: the pin 5 (i.e., positive input terminal) of Q is connected to the output terminal 4 of the rectifier circuit 111 through R1, and the pin 5 of Q is also connected to the ground terminal through R2. Pin 6 (i.e., the negative input terminal) of Q is connected to a voltage source VDD1 through R3, and pin 6 of Q is also connected to ground through R4; the 7-pin (i.e., output) of Q is coupled to a microcontroller (i.e., the main chip in the load circuit of fig. 2) via an optocoupler circuit 102. Pin 8 of Q is connected to a voltage source VDD3 and also to ground through C5. Pin 1 of Q is connected to ground by default, pin 2 of Q is connected to ground, pin 3 of Q is connected to ground through R9, pin 3 of Q is also connected to voltage source VDD4 through R10, and pin 4 of Q is connected to ground.

It should be noted that pin 7 of Q is connected to the microcontroller through the optocoupler circuit 102, so that the microcontroller collects the comparison result (i.e., the voltage of pin 7) of Q and controls the execution unit to execute the protection operation of the wiring circuit corresponding to the comparison result based on the comparison result; or the microcontroller controls the information output unit to output wiring prompt information based on the comparison result so as to prompt whether the wiring is correct or not.

Here, VDD1, VDD3, and VDD4 are all 15V.

Here, the opto-coupler circuit 102 has a strong anti-interference capability, and effectively protects the microcontroller.

It should be noted that R1 and R2 constitute a voltage step-down circuit for stepping down the voltage at the output terminal 4 of Q. In addition, R3, R4, and VDD1 constitute a reference voltage circuit for outputting a reference voltage, that is, a voltage of the 6-pin input of Q is a reference voltage.

Here, when the voltage of pin 5 of Q is greater than the voltage of pin 6 (i.e., the reference voltage), pin 7 of Q outputs a high level, which represents that the position where the input end of the rectifying circuit 111 is connected to the zero line is mistakenly connected to the live line; when the voltage of the pin 5 of the Q is less than the voltage of the pin 6, the pin 7 of the Q outputs low level, and the low level represents that the input end of the rectifying circuit 111 is correctly connected.

Here, the detection circuit 101 further includes a first capacitor C1, and C1 is connected in parallel across R2. C1 is used to filter the rectified voltage of the rectifying circuit 111.

The optical coupling circuit 102 mentioned above may specifically include: an optocoupler OC, a fifth resistor R5. Wherein, the OC consists of a light-emitting diode and a phototriode. The concrete connection mode is as follows: the pin 7 of the Q is connected with the anode of a light-emitting diode in the OC, and the cathode of the light-emitting diode is connected with the grounding end; the positive pole of the phototriode in the OC is connected with a second voltage source VDD2, and the negative pole of the phototriode is connected with the ground terminal of the R5.

Here, VDD2 is 5V.

Here, the optical coupler circuit 102 further includes: a second capacitor C2 and a third capacitor C3. The concrete connection mode is as follows: the C2 is connected in parallel with two ends of the LED, one end of the C3 is connected with VDD2, and the other end is connected with the ground end. Among them, C2 and C3 play a role of filtering.

The optical coupling circuit 102 further includes: a sixth resistor R6 and a fourth capacitor C4. The concrete connection mode is as follows: the cathode of the photosensitive diode is connected in series with the C4 through the R6 and then grounded. Wherein, R6 and C4 form an RC filter for filtering.

In addition, the connection protection circuit 10 further includes: one end of the seventh resistor R7, one end of the eighth resistor R8, and one end of the R7 are connected to the first voltage source VDD1, and the other end of the R7 is connected to the pin 7 of the output terminal of the detection circuit 101, and is also connected to the input terminal of the optical coupler circuit 102 through R8. Here, R7 and R8 function as a current limiter.

The connection protection circuit 10 further includes a first protection circuit 103, one end of the first protection circuit 103 is connected to the output terminal 4 pin of the rectification circuit 111, the other end is connected to the first end of the switching power supply, the second end of the switching power supply is connected to the output terminal 4 pin of the rectification circuit 111, and the third end is connected to the output terminal 1 pin of the rectification circuit 111.

The first protection circuit 103 is used for controlling the switching power supply of the load circuit 112 to be in a shutdown state when the wiring circuit has a wiring fault, and stopping supplying power to the load circuit 112.

The wiring protection circuit 10 further includes a second protection circuit 104, and two input terminals of the second protection circuit 104 are connected to two output terminals of the rectification circuit 111.

The second protection circuit 104 includes at least one electrolytic capacitor, and the withstand voltage value of the at least one electrolytic capacitor after being connected in series is larger than the withstand voltage threshold. And the withstand voltage threshold value is larger than the maximum voltage value after rectification when the wiring fails.

The second protection circuit 104 in fig. 2 may specifically include: electrolytic capacitors E1 and E2. The concrete connection mode is as follows: e1 and E2 are connected in series and then connected in parallel to two output ends of the sorting circuit 111.

If the detection circuit 101 detects that the position of the input end of the rectification circuit 111 connected with the zero line is mistakenly connected with the live line, the sum of the withstand voltage values of E1 and E2 is larger than the withstand voltage threshold value, and the electrolytic capacitor is protected.

Here, the load circuit 112 specifically includes: and other weak current circuits such as a switching power supply, a fan drive and a main chip.

Here, the rectifier circuit 111, that is, BR1, is composed of 4 diodes, and 2 pins and 3 pins as input terminals, and is connected to two output terminals of the three-phase four-wire power supply circuit 110. The rectifier circuit 111 is a circuit that converts ac power to dc power.

Here, the three-phase four-wire power supply circuit 110 specifically includes: connection port A, connection port B, connection port C, connection port N, relay RY1, relay RY2, relay RY3, relay RY4 and thermistor PTC. The concrete connection mode is as follows: c is connected with the 3 feet of BR1 through PTC, and C is connected with the 3 feet of BR1 through RY 4; n is directly connected with the 2 feet of BR 1. A is connected with 1 foot of BR2 through RY1, B is connected with 2 feet of BR2 through RY2, C is connected with 3 feet of BR2 through RY3, and 4 feet and 5 feet of BR2 are respectively connected with a compressor drive. BR2 is composed of 6 diodes (not all diodes are shown).

It should be noted that, if both input ends of the rectifying circuit 111 are connected to live wires, the rectified voltage is 538V dc (the ac voltage between the two live wires is 380V), and the withstand voltage values of E1 and E2 in fig. 2 may be 450V dc, and 900V in series, which is greater than 538V, that is, the second protection circuit composed of E1 and E2 achieves protection of the electrolytic capacitor.

It should be further noted that when the connection port a, the connection port B, the connection port C and the connection port N are powered on, the relays RY1, RY2, RY3 and RY4 are in a non-attraction state (i.e., a non-operation state), power is supplied to the BR1 through the PTC to enable the BR1 to operate, the maximum rectified voltage of the connection circuit is 374V direct current (calculated according to the highest mains supply 265V alternating current), and the preset operating voltage range can be smaller than 390V.

If the voltage of the pin 7 in the Q (an IC910 chip can be selected) is less than 390V, a low level is output, the microcontroller detects the low level, the display unit is controlled to display correct wiring information, the relays RY1, RY2, RY3 and RY4 are controlled to be in a pull-in state, and the wiring circuit works normally. If the voltage of a pin 7 in the Q is greater than 390V output high level, the microcontroller detects the high level to represent wiring errors, the relays RY1, RY2, RY3 and RY4 are in a non-attracting state, the PTC is connected in series into the circuit to play a role in protection, when the PTC gradually generates heat and divides voltage, the voltage of a rectifying circuit at the rear end of the PTC becomes smaller and smaller until the voltage is under-voltage and does not work, wiring error information is displayed through a display unit during the period, a worker is reminded to timely adjust the wiring mode, the power is supplied again to detect after the power is turned off and the wiring is correct, the relays RY1, RY2, RY3 and RY4 are in attracting states, and the wiring circuit starts to work normally.

Here, the voltage calculation formula for the 7-pin in Q is:

Vp＝15*R4*(R2+R1)/R2*(R3+R4)

here, fig. 3 is a schematic flowchart of a wire connection determining method in the embodiment of the present application. As shown in fig. 3, in particular,

step 301: starting;

step 302: the BR1 outputs rectified voltage, and detects whether the rectified voltage is overvoltage through a detection circuit; if yes, go to step 303; if not, go to step 304;

step 303: the relays RY1, RY2, RY3 and RY4 are not attracted, overvoltage information caused by wiring errors is transmitted to the microcontroller by the detection circuit, and then the microcontroller reports faults;

step 304: the relay RY1, the RY2, the RY3 and the RY4 are sucked, and the wiring circuit works normally;

step 305: the PTC generates heat and divides voltage until the BR1 has no output voltage, and the PTC is electrified again after the wiring mode is adjusted;

step 306: and (6) ending.

Based on the foregoing embodiments, the present application provides another specific circuit structure diagram, and fig. 4 is a schematic diagram of a third composition structure of the wiring protection circuit in the embodiments of the present application.

As shown in fig. 4, the wiring protection circuit 10 includes a detection circuit 101, and one input terminal of the detection circuit 101 is connected to the output terminal 4 of the rectification circuit 111, and the other input terminal is connected to the output terminal 1 (i.e., ground terminal) of the rectification circuit 111.

The detection circuit 101 may specifically include: the voltage comparator Q, first resistance R1, second resistance R2, third resistance R3, fourth resistance R4, resistance R9, resistance R10 and electric capacity C5. Wherein, Q comprises two voltage comparators.

The concrete connection mode is as follows: the pin 5 (i.e., positive input terminal) of Q is connected to the output terminal 4 of the rectifier circuit 111 through R1, and the pin 5 of Q is also connected to the ground terminal through R2. Pin 6 (i.e., the negative input terminal) of Q is connected to a voltage source VDD1 through R3, and pin 6 of Q is also connected to ground through R4; the pin 7 (i.e., output) of Q is coupled to the microcontroller through an opto-coupler circuit 102. Pin 8 of Q is connected to a voltage source VDD3 and also to ground through C5. Pin 1 of Q is connected to ground by default, pin 2 of Q is connected to ground, pin 3 of Q is connected to ground through R9, pin 3 of Q is also connected to voltage source VDD4 through R10, and pin 4 of Q is connected to ground. Among them, C5 plays a role of filtering.

It should be noted that pin 7 of Q is connected to the microcontroller through the optocoupler circuit 102, so that the microcontroller collects the comparison result (i.e., the voltage of pin 7) of Q and controls the execution unit to execute the protection operation of the wiring circuit corresponding to the comparison result based on the comparison result; or the microcontroller controls the information output unit to output wiring prompt information based on the comparison result so as to prompt whether the wiring is correct or not.

Here, VDD1, VDD3, and VDD4 are all 15V.

Here, the opto-coupler circuit 102 has a strong anti-interference capability, and effectively protects the microcontroller.

In addition, the pin 7 of the Q is connected with the microcontroller through the optocoupler circuit 102, so that the microcontroller collects the voltage of the pin 7 and controls the display unit to display the execution information corresponding to the voltage of the pin 7 of the Q.

It should be noted that R1 and R2 constitute a voltage reduction circuit for reducing the voltage at the output terminal 4 of BR 1. In addition, R3, R4, and VDD1 constitute a reference voltage circuit for outputting a reference voltage, that is, a voltage of the 6-pin input of Q is a reference voltage.

Here, when the voltage of pin 5 of Q is greater than the voltage of pin 6 (i.e., the reference voltage), pin 7 of Q outputs a high level, which represents that the position where the input end of the rectifying circuit 111 is connected to the zero line is mistakenly connected to the live line; when the voltage of the pin 5 of the Q is less than the voltage of the pin 6, the pin 7 of the Q outputs low level, and the low level represents that the input end of the rectifying circuit 111 is correctly connected.

Here, the detection circuit 101 further includes a first capacitor C1, and C1 is connected in parallel across R2. C1 is used to filter the rectified voltage of the rectifying circuit 111.

The optical coupling circuit 102 mentioned above may specifically include: an optocoupler OC, a fifth resistor R5. Wherein, the OC consists of a light-emitting diode and a phototriode. The concrete connection mode is as follows: the output end of the Q is connected with the anode of a light-emitting diode in the OC, and the cathode of the light-emitting diode is connected with the ground end; the positive pole of the phototriode in the OC is connected with a second voltage source VDD2, and the negative pole of the phototriode is connected with the ground terminal of the R5.

Here, VDD2 is 5V.

Here, the optical coupler circuit 102 further includes: a second capacitor C2 and a third capacitor C3. The concrete connection mode is as follows: the C2 is connected in parallel with two ends of the LED, one end of the C3 is connected with VDD2, and the other end is connected with the ground end. Among them, C2 and C3 play a role of filtering.

The optical coupling circuit 102 further includes: a sixth resistor R6 and a fourth capacitor C4. The concrete connection mode is as follows: the cathode of the photosensitive diode is connected in series with the C4 through the R6 and then grounded. Wherein, R6 and C4 form an RC filter for filtering.

In addition, the connection protection circuit 10 further includes: one end of the seventh resistor R7, one end of the eighth resistor R8, and one end of the R7 are connected to the first voltage source VDD1, and the other end of the R7 is connected to the pin 7 of the output terminal of the detection circuit 101, and is also connected to the input terminal of the optical coupler circuit 102 through R8. Here, R7 and R8 function as a current limiter.

The connection protection circuit 10 further includes a first protection circuit 103, one end of the first protection circuit 103 is connected to the output terminal 4 pin of the rectification circuit 111, the other end is connected to the first end of the switching power supply, the second end of the switching power supply is connected to the output terminal 4 pin of the rectification circuit 111, and the third end is connected to the output terminal 1 pin of the rectification circuit 111.

The first protection circuit 103 is used for controlling the switching power supply of the load circuit 112 to be in a shutdown state when the wiring circuit has a wiring fault, and stopping supplying power to the load circuit 112.

The wiring protection circuit 10 further includes a second protection circuit 104, and two input terminals of the second protection circuit 104 are connected to two output terminals of the rectification circuit 111.

The second protection circuit 104 includes at least one electrolytic capacitor, and the withstand voltage value of the at least one electrolytic capacitor after being connected in series is larger than the withstand voltage threshold. And the withstand voltage threshold is larger than the maximum value of rectified voltage in the case of wiring fault.

The second protection circuit 104 in fig. 4 may specifically include: and an electrolytic capacitor E1. The concrete connection mode is as follows: e1 is connected in parallel with two output ends of the rectifying circuit 111 (i.e. BR1), i.e. one end of E1 is connected with pin 4 of BR1, and the other end is connected with pin 1 of BR 1.

The second protection circuit 104 protects the electrolytic capacitor.

Here, when the detection circuit 101 detects that the position where the input end of the rectifying circuit 111 is connected to the zero line is erroneously connected to the live line, the withstand voltage value of E1 is greater than the withstand voltage threshold, and the electrolytic capacitor is protected. The withstand voltage threshold value is larger than the maximum voltage value after rectification when the wiring fails, the maximum voltage value after the wiring fails and is rectified by the rectification circuit is 538V, and the withstand voltage threshold value needs to be larger than 538V. The withstand voltage of E1 may be 550V.

Here, the load circuit 112 specifically includes: and other weak current circuits such as a switching power supply, a fan drive and a main chip. The first protection circuit 103 is used for controlling the on/off state of the switching power supply. If the detection circuit 101 detects that the pin 7 of Q outputs a high level, the first protection circuit 103 controls the switching power supply to be in a shutdown state, so that other circuits in the load circuit 112 are in a shutdown state, and the components are protected.

Here, the rectifier circuit 111, that is, BR1, is composed of 4 diodes, and 2 pins and 3 pins as input terminals, and is connected to two output terminals of the three-phase four-wire power supply circuit 110.

Here, the three-phase four-wire power supply circuit 110 specifically includes: connection port A, connection port B, connection port C, connection port N, relay RY1, relay RY2, relay RY3, relay RY4 and thermistor PTC. The concrete connection mode is as follows: c is connected with the 3 feet of BR1 through PTC, and C is connected with the 3 feet of BR1 through RY 4; n is directly connected with the 2 feet of BR 1. A is connected with 1 foot of BR2 through RY1, B is connected with 2 feet of BR2 through RY2, C is connected with 3 feet of BR2 through RY3, and 4 feet and 5 feet of BR2 are respectively connected with a compressor drive.

Fig. 5 is a fourth schematic structural diagram of the wiring protection circuit in the embodiment of the present application, and as shown in fig. 5, the wiring protection circuit includes a wiring circuit and a first protection circuit 103;

wherein the wiring circuit includes: a three-phase four-wire power supply circuit 110, a rectifier circuit 111, and a load circuit 112; two input ends of the rectifying circuit 111 are connected with two output ends of the three-phase four-wire power supply circuit 110; two output ends of the rectifying circuit 111 are connected with two input ends of the load circuit 112; the rectifying circuit 111 is configured to rectify the voltage output by the three-phase four-wire power supply circuit 110, and provide the rectified voltage to the load circuit 112;

the first protection circuit 103 is used for controlling the switching power supply of the load circuit 112 to be in a turned-off state when the wiring circuit has a wiring fault, and stopping supplying power to the load circuit 112.

It should be noted that the first protection circuit further includes other matching elements, such as one or more combinations of resistors and capacitors. Through the first protection circuit formed by combining one or more components, when the wiring circuit has a wiring fault, the switching power supply of the load circuit is controlled to be in a closed state, and the power supply to the load circuit is stopped, so that the components in the whole circuit are protected.

Based on the foregoing embodiments, a specific circuit structure diagram is provided in the present application, and fig. 6 is a schematic diagram of a fifth component structure of the wiring protection circuit in the embodiments of the present application.

As shown in fig. 6, the wiring protection circuit includes a wiring circuit, a first protection circuit 103, and a second protection circuit 104.

One end of the first protection circuit 103 is connected to the output terminal 4 pin of the rectification circuit 111, the other end is connected to the first end of the switching power supply, the second end of the switching power supply is connected to the output terminal 4 pin of the rectification circuit 111, and the third end is connected to the output terminal 1 pin of the rectification circuit 111.

The first protection circuit 103 is used for controlling the switching power supply of the load circuit 112 to be in a shutdown state when the wiring circuit has a wiring fault, and stopping supplying power to the load circuit 112.

The wiring protection circuit 10 further includes a second protection circuit 104, and two input terminals of the second protection circuit 104 are connected to two output terminals of the rectification circuit 111.

The second protection circuit 104 includes at least one electrolytic capacitor, and the withstand voltage value of the at least one electrolytic capacitor after being connected in series is larger than the withstand voltage threshold. And the withstand voltage threshold is larger than the maximum value of rectified voltage in the case of wiring fault.

The second protection circuit 104 in fig. 6 may specifically include: and an electrolytic capacitor E1. The concrete connection mode is as follows: e1 is connected in parallel with two output ends of the rectifying circuit 111 (i.e. BR1), i.e. one end of E1 is connected with pin 4 of BR1, and the other end is connected with pin 1 of BR 1.

The voltage resistance value of E1 is larger than the voltage resistance threshold value, so as to achieve the protection of the electrolytic capacitor. The withstand voltage threshold value is larger than the maximum voltage value after rectification when the wiring fails, the maximum voltage value after the wiring fails and is rectified by the rectification circuit is 538V, and the withstand voltage threshold value needs to be larger than 538V. The withstand voltage of E1 may be 550V.

The wiring circuit includes: a three-phase four-wire power supply circuit 110, a rectifier circuit 111, and a load circuit 112.

Here, the load circuit 112 specifically includes: and other weak current circuits such as a switching power supply, a fan drive and a main chip.

Here, the rectifier circuit 111, that is, BR1, is composed of 4 diodes, and 2 pins and 3 pins as input terminals, and is connected to two output terminals of the three-phase four-wire power supply circuit 110. The rectifier circuit 111 is a circuit that converts ac power to dc power.

Here, the three-phase four-wire power supply circuit 110 specifically includes: connection port A, connection port B, connection port C, connection port N, relay RY1, relay RY2, relay RY3, relay RY4 and thermistor PTC. The concrete connection mode is as follows: c is connected with the 3 feet of BR1 through PTC, and C is connected with the 3 feet of BR1 through RY 4; n is directly connected with the 2 feet of BR 1. A is connected with 1 foot of BR2 through RY1, B is connected with 2 feet of BR2 through RY2, C is connected with 3 feet of BR2 through RY3, and 4 feet and 5 feet of BR2 are respectively connected with a compressor drive. BR2 is composed of 6 diodes (not all diodes are shown).

Based on the foregoing embodiments, the present application provides another specific circuit structure diagram, and fig. 7 is a schematic diagram of a sixth constituent structure of the wiring protection circuit in the embodiments of the present application.

As shown in fig. 7, the wiring protection circuit includes a wiring circuit, a first protection circuit 103, and a second protection circuit 104.

One end of the first protection circuit 103 is connected to the output terminal 4 pin of the rectification circuit 111, the other end is connected to the first end of the switching power supply, the second end of the switching power supply is connected to the output terminal 4 pin of the rectification circuit 111, and the third end is connected to the output terminal 1 pin of the rectification circuit 111.

The first protection circuit 103 is used for controlling the switching power supply of the load circuit 112 to be in a shutdown state when the wiring circuit has a wiring fault, and stopping supplying power to the load circuit 112.

The wiring protection circuit 10 further includes a second protection circuit 104, and two input terminals of the second protection circuit 104 are connected to two output terminals of the rectification circuit 111.

The second protection circuit 104 includes at least one electrolytic capacitor, and the withstand voltage value of the at least one electrolytic capacitor after being connected in series is larger than the withstand voltage threshold. And the withstand voltage threshold is larger than the maximum value of rectified voltage in the case of wiring fault.

The second protection circuit 104 in fig. 7 may specifically include: electrolytic capacitors E1 and E2. The concrete connection mode is as follows: e1 and E2 are connected in series and then connected in parallel to two output ends of the rectifying circuit 111 (namely BR 1).

The sum of the withstand voltage values of E1 and E2 is greater than the withstand voltage threshold value, so that the electrolytic capacitor is protected. The withstand voltage threshold value is larger than the maximum voltage value after rectification when the wiring fails, the maximum voltage value after the wiring is normally rectified by the rectification circuit is 538V, and the withstand voltage threshold value needs to be larger than 538V. The dielectric breakdown values of E1 and E2 were both 450V and the sum was 900V, which was greater than 538V.

The wiring circuit includes: a three-phase four-wire power supply circuit 110, a rectifier circuit 111, and a load circuit 112.

Here, the load circuit 112 specifically includes: and other weak current circuits such as a switching power supply, a fan drive and a main chip.

Here, the rectifier circuit 111, that is, BR1, is composed of 4 diodes, and 2 pins and 3 pins as input terminals, and is connected to two output terminals of the three-phase four-wire power supply circuit 110. The rectifier circuit 111 is a circuit that converts ac power to dc power.

Here, the three-phase four-wire power supply circuit 110 specifically includes: connection port A, connection port B, connection port C, connection port N, relay RY1, relay RY2, relay RY3, relay RY4 and thermistor PTC. The concrete connection mode is as follows: c is connected with the 3 feet of BR1 through PTC, and C is connected with the 3 feet of BR1 through RY 4; n is directly connected with the 2 feet of BR 1. A is connected with 1 foot of BR2 through RY1, B is connected with 2 feet of BR2 through RY2, C is connected with 3 feet of BR2 through RY3, and 4 feet and 5 feet of BR2 are respectively connected with a compressor drive. BR2 is composed of 6 diodes (not all diodes are shown).

The embodiment of the application further discloses a wiring protection device, and the wiring protection device comprises: any one of the above embodiments of the present application is a wiring protection circuit.

The embodiment of the application also discloses a household appliance, and this household appliance includes: any one of the above embodiments of the present application is directed to a wiring protection circuit and a wiring circuit.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and all should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (15)

1. The wiring protection circuit is characterized by comprising a detection circuit, a control circuit and a control circuit, wherein the detection circuit is used for detecting the wiring state of the wiring circuit; wherein the content of the first and second substances,

the wiring circuit includes: the three-phase four-wire power supply circuit comprises a three-phase four-wire power supply circuit, a rectifying circuit and a load circuit; two input ends of the rectification circuit are connected with two output ends of the three-phase four-wire power supply circuit; two output ends of the rectifying circuit are connected with two input ends of the load circuit; the rectifying circuit is used for rectifying the voltage output by the three-phase four-wire power supply circuit and providing the rectified voltage for the load circuit;

the detection circuit is used for collecting rectified voltage of the rectifying circuit and detecting whether the rectified voltage meets a preset working voltage condition; and if the preset working voltage condition is not met, determining a wiring fault and executing the protection operation of the wiring circuit.

2. The wiring protection circuit of claim 1,

and if the preset working voltage condition is met, determining that the wiring is normal, and controlling the wiring circuit to work normally.

3. The wiring protection circuit of claim 2,

the wiring is normal, and two input ends of the rectification circuit are respectively connected with a live wire and a zero wire of the three-phase four-wire power circuit;

and the wiring fault representation indicates that two input ends of the rectification circuit are connected with a live wire of the three-phase four-wire power circuit.

4. The wiring protection circuit of claim 1,

the preset working voltage condition is as follows: the rectified voltage is within a preset voltage range.

5. The wiring protection circuit of claim 1,

the detection circuit includes: the circuit comprises a voltage comparator, a first resistor, a second resistor, a third resistor, a fourth resistor and a first capacitor;

the positive input end of the voltage comparator is connected with the first output end of the rectifying circuit through the first resistor and is grounded through the second resistor; the first capacitor is connected in parallel to two ends of the second resistor;

the negative input end of the voltage comparator is connected with a first voltage source through the third resistor and is grounded through the fourth resistor;

the output end of the voltage comparator is connected with the microcontroller, so that the microcontroller collects the comparison result of the voltage comparator and controls the execution unit to execute the protection operation of the wiring circuit corresponding to the comparison result based on the comparison result.

6. The wiring protection circuit of claim 5, wherein the execution unit is an information output unit,

the microcontroller is specifically configured to control the information output unit to output a wiring prompt information based on the comparison result, so as to prompt whether wiring is correct.

7. The wiring protection circuit of claim 5,

the wiring protection circuit further includes: an optocoupler circuit; the detection circuit is connected with the microcontroller through the optocoupler circuit; the optical coupling circuit is used for isolating the output end of the detection circuit from the microcontroller.

8. The wiring protection circuit of claim 7,

the optical coupling circuit includes: an optical coupler and a fifth resistor; the optical coupler consists of a light-emitting diode and a phototriode;

the output end of the detection circuit is connected with the anode of the light-emitting diode, and the cathode of the light-emitting diode is grounded;

a collector electrode of a phototriode in the optical coupler is connected with a second voltage source, and an emitter electrode of the phototriode is grounded through the fifth resistor;

the optical coupling circuit further includes: a second capacitor and a third capacitor;

the second capacitor is connected in parallel to two ends of the light emitting diode;

one end of the third capacitor is connected with the second voltage source, and the other end of the third capacitor is grounded;

the optical coupling circuit further includes: a sixth resistor and a fourth capacitor;

and the emitter of the phototriode is grounded after being connected in series with the fourth capacitor through the sixth resistor.

9. The wiring protection circuit of claim 7,

the wiring protection circuit further includes: a seventh resistor and an eighth resistor;

one end of the seventh resistor is connected with the first voltage source;

the other end of the seventh resistor is connected with the output end of the detection circuit and is also connected with the input end of the optical coupling circuit through the eighth resistor.

10. The wiring protection circuit of claim 1,

the wiring protection circuit further includes: a first protection circuit;

the first protection circuit is used for controlling a switching power supply of the load circuit to be in a closed state and stopping supplying power to the load circuit when the wiring circuit has wiring faults.

11. The wiring protection circuit of claim 10,

the wiring protection circuit further includes: a second protection circuit;

the second protection circuit includes: at least one electrolytic capacitor;

the at least one electrolytic capacitor is connected in series and then connected in parallel to two output ends of the rectifying circuit;

wherein, the withstand voltage value of the at least one electrolytic capacitor after being connected in series is larger than the withstand voltage threshold value.

12. A wiring protection circuit, characterized in that the wiring protection circuit comprises a wiring circuit and a first protection circuit;

the wiring circuit includes: the three-phase four-wire power supply circuit comprises a three-phase four-wire power supply circuit, a rectifying circuit and a load circuit; two input ends of the rectification circuit are connected with two output ends of the three-phase four-wire power supply circuit; two output ends of the rectifying circuit are connected with two input ends of the load circuit; the rectifying circuit is used for rectifying the voltage output by the three-phase four-wire power supply circuit and providing the rectified voltage for the load circuit;

the first protection circuit is used for controlling a switching power supply of the load circuit to be in a closed state and stopping supplying power to the load circuit when the wiring circuit has wiring faults.

13. The wiring protection circuit of claim 12,

the wiring protection circuit further comprises a second protection circuit;

the second protection circuit includes: at least one electrolytic capacitor;

the at least one electrolytic capacitor is connected in series and then connected in parallel to two output ends of the rectifying circuit;

wherein, the withstand voltage value of the at least one electrolytic capacitor after being connected in series is larger than the withstand voltage threshold value.

14. A wiring protection device, characterized in that it comprises a wiring protection circuit according to claims 1-13.

15. A household appliance, characterized in that it comprises a wiring protection circuit and a wiring circuit according to claims 1-13.

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