CN220366517U - Electric heating control circuit, electric auxiliary heating system and central air conditioner - Google Patents

Abstract

The utility model discloses an electric heating control circuit, an electric auxiliary heating system and a central air conditioner, wherein the electric heating control circuit comprises: the power supply interface is used for accessing an alternating current power supply; the contactors are sequentially connected in series between the power supply interface and the electric heating assembly; the main control board is electrically connected with the controlled ends of the contactors respectively and controls the on-off of each contactor. The technical scheme of the utility model aims to reduce the adhesion of an electric heating contactor in an electric auxiliary heating system so as to prevent potential safety hazards caused by electric heating dry combustion.

Description

Electric heating control circuit, electric auxiliary heating system and central air conditioner

Technical Field

The utility model relates to the technical field of central air conditioners, in particular to an electric heating control circuit, an electric auxiliary heating system and a central air conditioner.

Background

At present, in a domestic electric auxiliary heating system, electric heating is usually controlled by a single-stage contactor, and the power supply of the electric heating is switched on and off by controlling the on and off of the contactor. However, when the contactor is used in industry, the contact points are easily welded due to sudden increase of the accessed current, and the contactor is adhered, under the condition, electric heating can be directly electrified to generate heat, and if water in a water pipe is not available at the moment, the electric heating can be dry-burned, so that potential safety hazards are generated.

Disclosure of Invention

The utility model mainly aims to provide an electric heating control circuit, an electric auxiliary heating system and a central air conditioner, which aim to reduce the adhesion of an electric heating contactor in the electric auxiliary heating system so as to prevent potential safety hazards caused by electric heating dry combustion.

In order to achieve the above object, the present utility model provides an electric heating control circuit applied to a central air conditioner, the central air conditioner including an electric auxiliary heating system including an electric heating assembly, the electric heating control circuit including:

the power supply interface is used for accessing an alternating current power supply;

the contactors are sequentially connected in series between the power supply interface and the electric heating assembly;

the main control board is electrically connected with the controlled ends of the contactors respectively and controls the on-off of each contactor.

In some embodiments, the number of contactors is specifically two, including a first contactor and a second contactor;

the first contactor and the second contactor are sequentially connected in series between the power supply interface and the electric heating assembly, and the controlled end of the first contactor and the controlled end of the second contactor are respectively and electrically connected with the main control board.

In some embodiments, the central air conditioner further comprises a heat pump system and a water storage container, the heat pump system comprises a compressor, and the electric heating control circuit further comprises:

the water temperature sensor is arranged in the water storage container, the output end of the water temperature sensor is electrically connected with the main control board, and the water temperature sensor is used for collecting the water temperature in the water storage container and outputting a corresponding water temperature detection signal;

the controlled end of the dry heating alarm circuit is electrically connected with the main control board;

the main control board comprises a comparator, the input end of the comparator is electrically connected with the water temperature sensor, the output end of the comparator is connected with the controlled end of the dry heating alarm circuit and is used for comparing the voltage value of the received water temperature detection signal with the over-temperature voltage value, and when the compressor and the electric heating assembly are not in a working state and the voltage value of the water temperature detection signal reaches the over-temperature voltage value, the dry heating alarm circuit is controlled to output corresponding dry heating alarm information.

In some embodiments, the dry-fire alarm circuit includes any one of a wire controller, an LED lamp, and a buzzer.

In some embodiments, the electrical heating control circuit further comprises:

the switch assembly is connected in series between the power supply interface and the contactors;

the main control board is also used for controlling the switch assembly to be disconnected when the compressor and the electric heating assembly are not in a working state and the voltage value of the water temperature detection signal reaches an over-temperature voltage value.

In some embodiments, the electrical heating control circuit further comprises:

the temperature controller is connected in series between the power supply interface and the contactors, and is used for collecting the current ambient temperature around the electric heating assembly and disconnecting the power supply interface from the contactors when the current ambient temperature reaches the preset ambient temperature.

In some embodiments, the power interface has four terminals, a first phase hot terminal, a second phase hot terminal, a third phase hot terminal, and a neutral terminal, respectively.

The utility model also provides an electric auxiliary heating system which comprises an electric heating assembly and the electric heating control circuit, wherein the electric heating control circuit is electrically connected with the electric heating assembly.

In some embodiments, the electrically assisted heating system further comprises:

the electric control box, a plurality of contactors in the electric heating control circuit and the master control board layer in the electric heating control circuit are arranged in the electric control box.

The utility model also provides a central air conditioner which comprises a heat pump system and the electric heating control circuit.

According to the technical scheme, the multiple contactors are connected in series between the power supply interface and the electric heating assembly in a tail-to-tail mode, the controlled end of each contactor is electrically connected with the main control board, only when the multiple contactors are all conducted under the control of the main control board, the electric heating assembly can be connected with the power supply interface, the electric heating assembly works, the probability of adhesion of the multiple contactors is far smaller than that of adhesion of a single-stage contactor, and therefore the number of the contactors is increased, the occurrence of adhesion of the contactors is reduced, the possibility of dry burning of the heaters due to direct electrification is reduced, and potential safety hazards are avoided.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are only some embodiments of the present utility model, and other drawings may be obtained according to the structures shown in these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic block diagram of an embodiment of an electrical heating control circuit of the present utility model;

FIG. 2 is a schematic block diagram of another embodiment of an electrical heating control circuit of the present utility model;

FIG. 3 is a schematic block diagram of an electrical heating control circuit according to yet another embodiment of the present utility model;

FIG. 4 is a block diagram showing a schematic structure of a further embodiment of the electric heating control circuit of the present utility model;

FIG. 5 is a circuit diagram of an embodiment of an electrical heating control circuit according to the present utility model;

FIG. 6 is a schematic diagram of an embodiment of an electrically assisted heating system according to the present utility model.

Reference numerals illustrate:

reference numerals	Name of the name	Reference numerals	Name of the name
				100	Power supply interface	500	Dry combustion method alarm circuit
210	First contactor	600	Switch assembly
				220	Second contactor	700	Temperature controller
300	Main control board	800	Electric control box
				400	Water temperature sensor

The achievement of the objects, functional features and advantages of the present utility model will be further described with reference to the accompanying drawings, in conjunction with the embodiments.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

Furthermore, descriptions such as those referred to as "first," "second," and the like, are provided for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implying an order of magnitude of the indicated technical features in the present disclosure. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present utility model.

The utility model provides an electric heating control circuit which is applied to a central air conditioner.

When the central air conditioner is in operation, heat is mainly sent from a low-temperature end to a high-temperature end through a heat pump system (also called a host machine), so that refrigeration in summer or heating in winter is realized. In order to achieve the heating effect of the air conditioning system, research and development personnel add an electric auxiliary heating system into the central air conditioner, and the circulating water is heated before the heat pump system works, so that the temperature of the water is increased, and the air conditioning system achieves the optimal efficiency during working.

Referring to fig. 1 and 5, in one embodiment, the present utility model is applied to a central air conditioner, the central air conditioner includes an electric auxiliary heating system, the electric auxiliary heating system includes an electric heating assembly, and an electric heating control circuit includes:

the power supply interface 100, the power supply interface 100 is used for accessing an alternating current power supply;

a plurality of contactors, which are sequentially connected in series between the power supply interface 100 and the electric heating assembly;

the main control board 300 is electrically connected with the controlled ends of the contactors respectively, and controls the on-off of each contactor.

In this embodiment, the number of connection terminals of the power supply interface 100 and the number of switches inside the contactor are determined by the number of phases of the power supply, and when the power supply is three-phase four-wire alternating current, the power supply interface 100 has four connection terminals, namely a first-phase live wire terminal, a second-phase live wire terminal, a third-phase live wire terminal and a neutral wire terminal, and three linkage switches are inside the contactor.

It can be appreciated that in the conventional electric auxiliary heating system, a contactor is generally connected in series between the electric heating and power supply interface 100, and the power supply of the electric heating is turned on and off by controlling the on and off of the contactor. However, in practical application, there may be load increase of the contactor caused by ageing of the heating wire, so that current flowing through the contactor is suddenly increased, or the adopted contactor is poor in quality, and the welding point of the welding point is low, which can cause welding of the welding point of the contactor due to overheating, so that the contactor is adhered, once the contactor is adhered, the electric heating can be directly connected with the power supply interface 100, and the electric heating begins to be electrified and heated, if no water exists in the water pipe at this time, the electric heating can be dry-burned, and potential safety hazards are generated.

Therefore, the utility model adopts a multi-contactor control scheme, in the embodiment, the tail ends of the contactors are connected in series between the power supply interface 100 and the electric heating component, the controlled end of each contactor is electrically connected with the main control board 300, and only when the contactors are all conducted under the control of the main control board 300, the electric heating component can be connected with the power supply interface 100, so that the electric heating component works, and the probability of adhesion of the contactors is far smaller than that of the single-stage contactors, therefore, the utility model can reduce the adhesion of the contactors by increasing the number of the contactors.

Specifically, assuming that the adhesion probability of a single contactor is 1/N, (1/N) … … (1/N), where N is a positive integer greater than 1, (1/N) … … (1/N) is far less than 1/N, when the control scheme of multiple contactors is adopted, the probability that the electric heating component is directly connected to the power supply interface 100 due to adhesion of the contactors is lower, so that the possibility of dry burning of the heater due to direct energization is reduced, and potential safety hazards are avoided.

When the central air conditioner is in normal operation, if the user sets the central air conditioner in a heating state, the electric auxiliary heating system starts to operate, and the main control board 300 outputs conduction control signals to the plurality of contactors simultaneously to enable the plurality of contactors to be all conducted, and at the moment, the electric heating assembly is connected with the power supply interface 100 to start to operate.

If the user sets the central air conditioner in a state of stopping heating, the main control board 300 outputs turn-off control signals to the plurality of contactors at the same time, and when the contactors in the electric auxiliary heating system are not adhered, the plurality of contactors are all turned off, so that the connection between the electric heating assembly and the power supply interface 100 is disconnected, and the heating assembly stops heating; when the contactor of the electric auxiliary heating system is stuck, the contactor which is not stuck is turned off after receiving the turn-off control signal, and the connection between the electric heating assembly and the power supply interface 100 is disconnected.

According to the utility model, by adopting a multi-contactor control scheme, a plurality of contactors are connected in series between the power supply interface 100 and the electric heating component in a tail-to-tail mode, the controlled end of each contactor is electrically connected with the main control board 300, and only when the plurality of contactors are all conducted under the control of the main control board 300, the electric heating component can be connected with the power supply interface 100, so that the electric heating component works, and the probability of adhesion of the plurality of contactors is far smaller than that of the single-stage contactor, so that the number of contactors is increased, the occurrence of adhesion of the contactors is reduced, the possibility of dry burning of the heater due to direct energization is reduced, and potential safety hazards are avoided.

Referring to fig. 1 and 5, in one embodiment, the number of contactors is two, including a first contactor 210 and a second contactor 220;

the first contactor 210 and the second contactor 220 are sequentially connected in series between the power supply interface 100 and the electric heating assembly, and the controlled end of the first contactor 210 and the controlled end of the second contactor 220 are respectively electrically connected with the main control board 300.

It should be noted that, although the more contactors, the lower the probability of adhesion of a plurality of contactors at the same time, the contactors are not switching elements with small volumes such as MOS transistors and triodes, so when the number of contactors is larger, the more occupied space is, therefore in this embodiment, two contactors are provided, including the first contactor 210 and the second contactor 220, and the probability of adhesion of the first contactor 210 and the second contactor 220 at the same time is (1/N) ×1/N, which is far less than 1/N, so that the probability that the heating assembly is directly connected to the power supply interface 100 due to adhesion of the contactors can be reduced, and because the number of contactors is smaller, excessive waste of space resources of the auxiliary heating system cannot be caused.

Specifically, when the central air conditioner is in normal operation, if the user sets the central air conditioner in a heating state, the electric auxiliary heating system starts to operate, and the main control board 300 outputs a conduction control signal to the first contactor 210 and the second contactor 220 at the same time, so that the first contactor 210 and the second contactor 220 are turned on, and at this time, the electric heating assembly is connected to the power supply interface 100, and starts to operate.

If the user sets the central air conditioner in a state of stopping heating, the main control board 300 in the electric auxiliary heating system outputs the turn-off control signal to the plurality of contactors at the same time, when the first contactor 210 is stuck, the second contactor 220 is turned off after receiving the turn-off control signal, and when the second contactor 220 is stuck, the first contactor 210 is turned off after receiving the turn-off control signal, thereby disconnecting the connection between the electric heating assembly and the power supply interface 100.

Referring to fig. 2 and 5, in an embodiment, the air conditioner further includes a heat pump system and a water storage container, the heat pump system includes a compressor, and the electric heating control circuit further includes:

the water temperature sensor 400 is arranged in the water storage container, the output end of the water temperature sensor 400 is electrically connected with the main control board 300, and the water temperature sensor 400 is used for collecting the water temperature in the water storage container and outputting a corresponding water temperature detection signal;

the control end of the dry-fire alarm circuit 500 is electrically connected with the main control board 300;

the main control board 300 comprises a comparator, wherein the input end of the comparator is electrically connected with the water temperature sensor 400, the output end of the comparator is connected with the controlled end of the dry-burning alarm circuit 500, and the main control board is used for comparing the voltage value of the received water temperature detection signal with the over-temperature voltage value, and controlling the dry-burning alarm circuit 500 to output corresponding dry-burning alarm information when the compressor and the electric heating assembly are not in a working state and the voltage value of the water temperature detection signal reaches the over-temperature voltage value.

In this embodiment, the dry-fire alarm circuit 500 includes any one of a wire controller, an LED lamp, and a buzzer.

When the electric auxiliary heating system works normally, the water temperature sensor 400 outputs a corresponding water temperature detection signal to the main control board 300 according to the collected water temperature, a comparator and a memory are integrated in the main control board 300, an over-temperature voltage value representing the dry heating temperature of the electric heating assembly is prestored in the memory, and the dry heating temperature is determined by research personnel according to actual requirements, such as 90 ℃, 95 ℃ and the like.

The comparator compares the voltage value of the connected water temperature detection signal with the over-temperature voltage value, and because the voltage value of the water temperature detection signal and the water temperature represented by the water temperature detection signal are in positive correlation, when the comparator detects that the voltage value of the water temperature detection signal does not reach the over-temperature voltage value, the electric auxiliary heating system is not dry-heated at the moment, the comparator does not output a dry-heating alarm control signal, and the dry-heating alarm circuit 500 does not work; when the comparator detects that the voltage value of the water temperature detection signal reaches the over-temperature voltage value, a corresponding dry-burning alarm control signal is output to the dry-burning alarm circuit 500, so that the dry-burning alarm circuit 500 is controlled to display a dry-burning fault word, flash a red light or sound, and the staff is prompted that the electric auxiliary heating system generates dry burning.

Referring to fig. 3 and 5, in an embodiment, the electric heating control circuit further includes:

the switch assembly 600, the switch assembly 600 is connected in series between the power supply interface 100 and the plurality of contactors;

the main control board 300 is further configured to control the switch assembly 600 to disconnect the electric heating assembly from the power supply interface 100 when the compressor and the electric heating assembly are not in a working state and the voltage value of the water temperature detection signal reaches an over-temperature voltage value.

In this embodiment, the switch assembly 600 may be a multi-line switching device such as a circuit breaker, a three pole three throw switch, or the like.

When the electric auxiliary heating system works, if the comparator detects that the voltage value of the water temperature detection signal does not reach the over-temperature voltage value, the electric auxiliary heating system is not dry-burned at the moment, the comparator does not output a switch turn-off control signal, and the switch assembly 600 is kept in a closed state; when the comparator detects that the voltage value of the water temperature detection signal reaches the over-temperature voltage value, a switch turn-off control signal is output to the switch assembly 600 to control the switch assembly 600 to disconnect the electric heating assembly from the power supply interface 100, so as to avoid continuous dry burning of the electric heating assembly.

Referring to fig. 4 and 5, in an embodiment, the electric heating control circuit further includes:

the temperature controller 700, the temperature controller 700 is connected in series between the power supply interface 100 and the plurality of contactors, and the temperature controller 700 is used for acquiring the current ambient temperature around the electric heating assembly and disconnecting the power supply interface 100 from the plurality of contactors when the current ambient temperature reaches the preset ambient temperature.

In this embodiment, the temperature controller 700 has a temperature detection function, and is capable of collecting the ambient temperature around the electric heating assembly, and the preset ambient temperature is pre-stored in the temperature controller 700, and is set by a developer according to actual requirements during design, for example, when the contactor is not adhered, the working temperature of the electric heating assembly is usually 30 ℃, 60 ℃ or the like, and when the contactor is adhered, the working temperature of the electric heating assembly exceeds 60 ℃ and may reach 90 ℃ or the like when the electric heating assembly is directly electrified, so in this embodiment, the preset ambient temperature may be set to 60 ℃.

Specifically, when the electric auxiliary heating system works, the temperature controller 700 compares the acquired current environmental temperature with the preset environmental temperature, and when the current environmental temperature does not reach the preset environmental temperature, it is indicated that the electric auxiliary heating system does not have dry heating yet, and at the moment, the electric auxiliary heating system is kept in a closed state; when the current ambient temperature reaches the preset ambient temperature, the electric auxiliary switch is turned off at this time to disconnect the connection between the electric heating assembly and the power supply interface 100, so as to avoid continuous dry heating of the electric heating assembly.

The utility model also provides an electric auxiliary heating system, which comprises an electric heating assembly and the electric heating control circuit, wherein the electric heating control circuit is electrically connected with the electric heating assembly; because the electric auxiliary heating system adopts all the technical schemes of all the embodiments, the electric auxiliary heating system at least has all the beneficial effects brought by the technical schemes of the embodiments, and the description is omitted herein.

Referring to fig. 6, in an embodiment, the electric auxiliary heating system further comprises:

the electric cabinet 800, a plurality of contactors in the electric heating control circuit and the main control board 300 in the electric heating control circuit are stacked in the electric cabinet.

In this embodiment, the electric cabinet 800 may be rectangular, trapezoidal or other shapes, and is used to fix the plurality of contactors in the electric heating control circuit and the main control board 300, and prevent dust from entering the main control board 300 to cause a short circuit between circuits carried on the main control board 300, so as to ensure the safety and stability inside the main control board 300, and when the electric heating control circuit works, the positional relationship between the plurality of contactors and the main control board 300 will not change due to the fixing effect of the electric cabinet 800, and the electric cabinet 800 has a protection effect on the outside of the electric heating control circuit, and the electric cabinet 800 mainly resists external load with middle plane stress uniformly distributed along the thickness, rather than bending stress varying along the thickness, so as to have a better carrying effect on external force.

The utility model also provides a central air conditioner which comprises a heat pump system and the electric auxiliary heating system; because the electric auxiliary heating system adopts all the technical schemes of all the embodiments, the electric auxiliary heating system at least has all the beneficial effects brought by the technical schemes of the embodiments, and the description is omitted herein.

The foregoing description of the embodiments of the present utility model is merely an optional embodiment of the present utility model, and is not intended to limit the scope of the utility model, and all equivalent structural modifications made by the present utility model in the light of the present utility model, the description of which and the accompanying drawings, or direct/indirect application in other related technical fields are included in the scope of the utility model.

Claims (10)

1. An electric heating control circuit for a central air conditioner, the central air conditioner comprising an electric auxiliary heating system comprising an electric heating assembly, characterized in that the electric heating control circuit comprises:

the power supply interface is used for accessing an alternating current power supply;

the contactors are sequentially connected in series between the power supply interface and the electric heating assembly;

the main control board is electrically connected with the controlled ends of the contactors respectively and controls the on-off of each contactor.

2. The electrical heating control circuit of claim 1, wherein the number of contactors is two, including a first contactor and a second contactor;

the first contactor and the second contactor are sequentially connected in series between the power supply interface and the electric heating assembly, and the controlled end of the first contactor and the controlled end of the second contactor are respectively and electrically connected with the main control board.

3. The electrical heating control circuit of claim 2, wherein the central air conditioner further comprises a heat pump system and a water reservoir, the heat pump system comprising a compressor, the electrical heating control circuit further comprising:

the water temperature sensor is arranged in the water storage container, the output end of the water temperature sensor is electrically connected with the main control board, and the water temperature sensor is used for collecting the water temperature in the water storage container and outputting a corresponding water temperature detection signal;

the controlled end of the dry heating alarm circuit is electrically connected with the main control board;

the main control board comprises a comparator, the input end of the comparator is electrically connected with the water temperature sensor, the output end of the comparator is connected with the controlled end of the dry heating alarm circuit and is used for comparing the voltage value of the received water temperature detection signal with the over-temperature voltage value, and when the compressor and the electric heating assembly are not in a working state and the voltage value of the water temperature detection signal reaches the over-temperature voltage value, the dry heating alarm circuit is controlled to output corresponding dry heating alarm information.

4. The electrical heating control circuit of claim 3, wherein the dry-fire alarm circuit comprises any one of a wire controller, an LED lamp, and a buzzer.

5. The electrical heating control circuit of claim 3, wherein the electrical heating control circuit further comprises:

the switch assembly is connected in series between the power supply interface and the contactors;

the main control board is also used for controlling the switch assembly to be disconnected when the compressor and the electric heating assembly are not in a working state and the voltage value of the water temperature detection signal reaches an over-temperature voltage value.

6. The electrical heating control circuit of claim 1, wherein the electrical heating control circuit further comprises:

the temperature controller is connected in series between the power supply interface and the contactors, and is used for collecting the current ambient temperature around the electric heating assembly and disconnecting the power supply interface from the contactors when the current ambient temperature reaches the preset ambient temperature.

7. The electrical heating control circuit of claim 1 wherein the power interface has four terminals, a first phase power terminal, a second phase power terminal, a third phase power terminal, and a neutral terminal, respectively.

8. An electric auxiliary heating system comprising an electric heating assembly and an electric heating control circuit according to any one of claims 1-7, the electric heating control circuit being electrically connected to the electric heating assembly.

9. The electrical auxiliary heating system of claim 8, further comprising:

the electric control box, a plurality of contactors in the electric heating control circuit and the master control board layer in the electric heating control circuit are arranged in the electric control box.

10. A central air conditioner, characterized in that it comprises a heat pump system and an electric auxiliary heating system according to claim 9.