CN105371544A - A heat pump system, its control method and clothes dryer - Google Patents

Abstract

The invention discloses a heat pump system, its control method and a clothes dryer, and relates to the technical field of heat pumps. The heat pump system includes a heat pump motor, the heat pump motor has a main coil and an auxiliary coil, and also includes a control unit and a capacitor circuit connected in series with the auxiliary coil, and the control unit is used for adjusting the capacitance value of the capacitor circuit. At the same time, a control method for the above-mentioned heat pump system is proposed. In the heat pump system provided by the present invention, the capacitance value of the capacitor circuit connected in series with the secondary coil of the heat pump motor can be adjusted. When it is necessary to increase the heat output, for example, the heat pump system is in the initial operation stage when the heat pump system is started, and the heat pump system receives an external signal to increase the heat output. , or when the external ambient temperature is low, the control unit adjusts the connected capacitor value, which can quickly generate more heat, rapidly increase the temperature of the heat pump system, shorten the warm-up time, and greatly improve user comfort.

Description

A heat pump system, its control method and clothes dryer

technical field

The invention relates to the technical field of heat pumps, in particular to a heat pump system, a control method thereof, and a clothes dryer with the heat pump system.

Background technique

Existing heat pump systems mainly include fixed frequency heat pump systems and variable frequency heat pump systems. The electrical diagram of the fixed-frequency heat pump system is shown in Figure 1, including the heat pump motor 1', the heat pump motor 1' has a main coil 2' and a secondary coil 3', and the secondary coil 3' is connected in series with a running capacitor 4' and a running switch 5 '. The cost of the fixed frequency heat pump system is relatively low, the process is relatively simple, the quality is stable and reliable, and the maintenance cost is low. However, since the fixed frequency heat pump system has only one operating capacitor, its heating efficiency cannot be changed, and the heating efficiency is low, especially when it is turned on. , It takes a long time to warm up, for example, it takes about 5 minutes for the air conditioner to start blowing hot air after it is turned on, and the temperature rise of the clothes dryer is very slow in the first 10 minutes, which greatly affects the user experience. Although the frequency conversion heat pump system has high heating efficiency, it also has many defects such as high cost, complicated process, many fault points in long-term use, and high maintenance cost.

In response to the above problems, the Chinese patent application No. 03109906.8 proposed a heat pump central air conditioner that can change the capacity and load to realize energy saving of the system. One or more fixed frequency compressors are connected in parallel to the fixed frequency compressors of the conventional heat pump system. , use the CPU to precisely control the start and stop of the compressor and the opening of the expansion and throttling element, so that the air conditioner load is in the highest efficiency state of the system within the adjustable range. Realized the variable capacity and load of central air-conditioning.

The above-mentioned patent uses parallel connection of fixed-frequency compressors to change the efficiency of the heat pump, which has a complicated structure and greatly increases the production cost of the heat pump system.

In view of the above problems, a new heat pump system is urgently needed to solve the problems of complex structure and high cost in the prior art.

Contents of the invention

An object of the present invention is to provide a heat pump system with simple and reliable structure, low cost and effective improvement of heating efficiency.

Another object of the present invention is to propose a control method for a heat pump system that can effectively improve heating efficiency.

Another object of the present invention is to provide a clothes dryer with high drying efficiency.

For reaching this purpose, on the one hand, the present invention adopts following technical scheme:

A heat pump system includes a heat pump motor, a control unit and an adjustable capacitance circuit connected to a coil of the heat pump motor, and the control unit is used to adjust the capacitance value of the capacitance circuit.

Preferably, the heat pump motor has a primary coil and a secondary coil, and the capacitor circuit is connected in series with the secondary coil.

Preferably, the capacitor circuit includes at least one running capacitor circuit and at least one auxiliary capacitor circuit connected in parallel;

Each of the running capacitor circuits includes a running capacitor and a running switch that controls the series connection of the running capacitors;

Each of the auxiliary capacitor circuits includes an auxiliary capacitor or an auxiliary capacitor group, and an auxiliary switch for controlling the auxiliary capacitor or the auxiliary capacitor group;

The control unit adjusts the capacitance value of the capacitance circuit by controlling the operation switch and the auxiliary switch.

Preferably, the auxiliary capacitor group includes at least two auxiliary capacitors connected in parallel.

Preferably, the capacitive circuit includes at least one variable capacitor.

On the other hand, the present invention adopts the following technical solutions:

A control method for a heat pump system as described above, wherein the control unit adjusts the capacitance value of the capacitance circuit according to the operating state of the heat pump system and/or external signals.

Preferably, the control unit increases the capacitance value of the capacitance circuit during the initial operation stage of the heat pump system and/or when receiving a heat output increasing signal.

Preferably, when the heat pump system is in the initial operation stage, the control unit controls to increase the capacitance value of the capacitor circuit from the original first capacitance value to the second capacitance value, and when the heat pump system reaches a balance Afterwards, the control unit controls to adjust the capacitance value of the capacitance circuit from the second capacitance value back to the original first capacitance value.

Preferably, the control unit adjusts the capacitance value of the capacitance circuit according to the ambient temperature.

Preferably, multiple temperature ranges are pre-stored in the control unit, and each temperature range corresponds to a target capacitance value. The control unit obtains the current ambient temperature, determines the temperature range in which the current ambient temperature is located, and controls the capacitor to The capacitance value of the circuit is adjusted to the target capacitance value corresponding to the temperature range.

In another aspect, the present invention adopts the following technical solutions:

A clothes dryer having the heat pump system as described above.

The beneficial effects of the present invention are:

In the heat pump system provided by the present invention, the capacitance value of the capacitor circuit connected to the coil of the heat pump motor can be adjusted by the control unit. When the external heat output signal is raised, or when the external ambient temperature is low, the control unit adjusts the capacitance value connected to the heat pump motor, which can quickly generate more heat, rapidly increase the temperature of the heat pump system, shorten the warm-up time, and greatly improve user comfort.

The control method of the heat pump system provided by the present invention is that the control unit adjusts the capacitance value of the capacitor circuit according to the operating state of the heat pump system and/or external signals, thereby changing the heating efficiency of the heat pump system, and the adjustment method is simple and easy.

Description of drawings

Figure 1 is an electrical diagram of an existing fixed-frequency heat pump system;

Fig. 2 is an electrical diagram of the heat pump system provided by Embodiment 1 of the present invention;

Fig. 3 is an electrical diagram of the heat pump system provided by Embodiment 2 of the present invention;

Fig. 4 is an electrical diagram of the heat pump system provided by Embodiment 3 of the present invention.

In the figure, 1', heat pump motor; 2', main coil; 3', secondary coil; 4', running capacitor; 5', running switch;

1. Heat pump motor; 2. Main coil; 3. Secondary coil; 4. Running capacitor; 5. Running switch; 6. Auxiliary capacitor; 7. Auxiliary switch; 8. Control unit; 9. First auxiliary capacitor; 10. Second 1. Auxiliary switch; 11. Second auxiliary capacitor; 12. Second auxiliary switch; 13. Auxiliary capacitor group.

detailed description

The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and through specific implementation methods.

The invention provides a heat pump system. In the system, the heat pump motor has a main coil and a secondary coil. A capacitor circuit with adjustable capacitance is connected in series on the secondary coil. The series circuit formed by the primary coil, the secondary coil and the capacitor circuit is connected in parallel. The capacitance value of the capacitor circuit can be adjusted by the control unit of the heat pump system. For example, when the heat pump system is in the initial operation stage, when the heat pump system receives a signal from the outside to increase the heat output, or when the external ambient temperature is low, the control unit adjusts The capacitance value connected to the heat pump motor can quickly generate more heat, rapidly increase the temperature of the heat pump system, shorten the warm-up time, and greatly improve the comfort of the user. It is suitable for household appliances that require heating systems such as air conditioners, clothes dryers, heat pump water heaters, and washing and drying machines.

Embodiment one:

This embodiment provides a heat pump system, as shown in Figure 2, the heat pump motor of the heat pump system has a main coil 2 and a secondary coil 3, the secondary coil 3 is connected in series with a running capacitor circuit, the running capacitor circuit includes a running capacitor 4 and control running The operation switch 5 of the capacitor 4 is also connected in parallel with an auxiliary capacitor circuit on the operation capacitor circuit formed by the operation capacitor 4 and the operation switch 5 . The auxiliary capacitor circuit includes an auxiliary capacitor 6 and an auxiliary switch 7 for controlling the auxiliary capacitor 6 . The running switch 5 and the auxiliary switch 7 are generally relays in the PCB circuit. The control unit 8 can control the operation switch 5 and the auxiliary switch 7 to be turned on and off.

The control process of the heat pump system is as follows: when the heat pump system is just started and is in the initial operation stage, the control unit 8 controls both the operation switch 5 and the auxiliary switch 7 to be closed, so that a large capacitor is connected, and the heat pump motor generates more heat, so as to rapidly increase the temperature of the heat pump system and realize a rapid heat engine. When the heat pump system reaches equilibrium, the control unit 8 controls to turn off the auxiliary switch 7, and the operation switch 5 is still closed. The operation of the heat pump system can be maintained through the operation capacitor 4. When the ambient temperature is low, such as lower than a preset temperature, the control unit 8 controls to close the auxiliary switch 7 and the operation switch 5 . This control not only shortens the start-up time of the heat pump system, but also ensures the heating efficiency of the heat pump system.

In addition, the user can also set the heating mode according to the needs. For example, two buttons are set, one is the normal heating mode button, and the other is the high-power heating mode button. When the user presses the normal heating mode button, the control unit 8 controls the auxiliary switch 7 to be disconnected, and the operation switch 5 is closed. When the user presses the high-power heating mode button, the control unit controls the auxiliary switch 7 and the operation switch 5 to be closed.

In addition, it should be noted that since the winding of the heat pump motor has been immersed in the refrigerant, when the heat pump motor is working, the refrigerant has been circulating, and the heat emitted by the heat pump motor will be taken away by the refrigerant in time, so that the heat pump can match the capacitor The range of capacity is large, and there will be no problem of excessive heating of the motor.

Embodiment two:

This embodiment provides a heat pump system. As shown in FIG. 3 , the auxiliary coil 3 of the heat pump motor 1 of the heat pump system is connected in series with a running capacitor circuit, and the running capacitor circuit includes a running capacitor 4 and a running switch 5 for controlling the running capacitor 4 . Two auxiliary capacitor circuits are connected in parallel on the operating capacitor circuit formed by the operating capacitor 4 and the operating switch 5, wherein one auxiliary capacitor circuit includes a first auxiliary capacitor 9 and a first auxiliary switch 10 for controlling the first auxiliary capacitor 9, and the other auxiliary capacitor circuit The capacitor circuit includes a second auxiliary capacitor 11 and a second auxiliary switch 12 for controlling the second auxiliary capacitor 11 . The running switch 5, the first auxiliary switch 10 and the second auxiliary switch 12 are generally relays in a PCB circuit. The control unit 8 can control the operation switch 5 , the first auxiliary switch 10 and the second auxiliary switch 12 to be turned on and off.

The control process of the heat pump system is as follows: when the heat pump system is just started and is in the initial operation stage, the control unit 8 controls the operation switch 5, the first auxiliary switch 10 and the second auxiliary switch 12 to be closed, so as to perform the operation with the maximum power. Heating, quickly raising the temperature of the heat pump system to achieve a fast heat engine. When the heat pump system reaches equilibrium, the control unit 8 controls the opening and closing of each switch according to the ambient temperature. Acquire the current ambient temperature once at a predetermined time. When the current ambient temperature is higher than the first preset temperature, the control unit 8 controls to disconnect the first auxiliary switch 10 and the second auxiliary switch 12, and the operation switch 5 remains closed. At this time, only the operation capacitor 4 access, due to the high temperature, the operation of the heat pump system can be maintained through the operation of the operation capacitor 4; when the current ambient temperature is less than or equal to the first preset temperature and greater than the second preset temperature, the control unit controls the closing of the first auxiliary switch 10 and the operation switch 5, the second auxiliary switch 12 remains off, at this time the operation capacitor 4 and the first auxiliary capacitor 9 are connected; when the current ambient temperature is less than or equal to the second preset temperature, the control unit 8 controls the operation switch 5 1. Both the first auxiliary switch 10 and the second auxiliary switch 12 are closed, and at this time, the running capacitor 4 , the first auxiliary capacitor 9 and the second auxiliary capacitor 11 are connected.

Tests have shown that applying the heat pump system provided in this embodiment to a heat pump clothes dryer can effectively improve the drying efficiency of the clothes dryer. For example, apply it to an 8kg heat pump clothes dryer with refrigerant R134A, and conduct a full-load test according to the European standard test procedure. The test results are: when the ambient temperature is 23°C, using a 10uf capacitor takes 190 minutes to dry, while using a 17uf capacitor, it only takes 160 minutes to dry; when the ambient temperature is 5°C, it takes 260 minutes to dry with a 10uf capacitor, and only 170 minutes to dry with a 27uf capacitor. It can be known from the above tests that the use of the heat pump system provided by this embodiment can greatly shorten the drying time and greatly improve the user experience of the product.

Among them, the number of auxiliary capacitors is not limited to two, and the number can be set according to actual environmental requirements; it is not limited to storing the first preset temperature and the second preset temperature in the control unit, and can be stored in the control unit according to requirements. Multiple temperature ranges are set, and each temperature range corresponds to a target capacitance value, which can further improve the control accuracy of the heat pump system.

Embodiment three:

This embodiment provides a heat pump system. As shown in FIG. 4 , the auxiliary coil 3 of the heat pump motor 1 of the heat pump system is connected in series with a running capacitor circuit. The running capacitor circuit includes a running capacitor 4 and a running switch 5 for controlling the running capacitor 4. Two auxiliary capacitor circuits are connected in parallel on the operating capacitor circuit formed by the operating capacitor 4 and the operating switch 5, one of which includes an auxiliary capacitor 6 and the first auxiliary switch for controlling the auxiliary capacitor 6, and the other auxiliary capacitor circuit includes an auxiliary capacitor group 13 and the second auxiliary switch 12 controlling the auxiliary capacitor bank 13, the auxiliary capacitor bank 13 includes two capacitors connected in parallel. The running switch 5, the first auxiliary switch 10 and the second auxiliary switch 12 are generally relays in a PCB circuit. The control unit 8 can control the operation switch 5 , the first auxiliary switch 10 and the second auxiliary switch 12 to be turned on and off.

The control process of the heat pump system is similar to that of the second embodiment, and will not be repeated here.

Embodiment four:

This embodiment provides a heat pump system, the structure of which is basically the same as that of Embodiment 1. The auxiliary coil of the heat pump motor in this system is connected in series with a running capacitor circuit, and an auxiliary capacitor circuit is connected in parallel with the running capacitor circuit. The auxiliary capacitor circuit includes Auxiliary capacitor and auxiliary switch to control the auxiliary capacitor.

The difference is that the auxiliary capacitor in this embodiment is a variable capacitor, and the control unit can adjust the capacitance value of the auxiliary capacitor according to the operating state of the heat pump system or received external signals, thereby changing the total capacitance value connected, to obtain the desired heating efficiency.

The above describes the technical principles of the present invention in conjunction with specific embodiments. These descriptions are only for explaining the principles of the present invention, and cannot be construed as limiting the protection scope of the present invention in any way. Based on the explanations herein, those skilled in the art can think of other specific implementation modes of the present invention without creative work, and these modes will all fall within the protection scope of the present invention.

Claims (10)

1. A heat pump system, comprising a heat pump motor, characterized in that: it also includes a control unit (8) and a capacitor circuit with an adjustable capacitance value connected to the coil of the heat pump motor, and the control unit (8) is used for adjusting the capacitance value of the capacitance circuit. 2. A heat pump system according to claim 1, characterized in that: the capacitor circuit comprises at least one operating capacitor circuit and at least one auxiliary capacitor circuit connected in parallel; Each of the running capacitor circuits includes a running capacitor (4) and a running switch (5) for controlling the running capacitor; Each of the auxiliary capacitor circuits includes an auxiliary capacitor (6) or an auxiliary capacitor group (13), and an auxiliary switch (7, 10, 12) for controlling the auxiliary capacitor (6) or the auxiliary capacitor group (13); The control unit (8) adjusts the capacitance value of the capacitance circuit by controlling the operation switch (5) and the auxiliary switches (7, 10, 12). 3. A heat pump system according to claim 2, characterized in that the auxiliary capacitor bank (13) includes at least two auxiliary capacitors connected in parallel. 4. A heat pump system according to claim 1, wherein the capacitor circuit comprises at least one variable capacitor. 5. A control method for a heat pump system according to any one of claims 1 to 4, characterized in that: the control unit (8) adjusts the capacitor according to the operating state of the heat pump system and/or external signals The capacitance value of the circuit. 6. A control method for a heat pump system according to claim 5, characterized in that: the control unit (8) increases The capacitance value of the capacitance circuit. 7. The control method of a heat pump system according to claim 6, characterized in that: when the heat pump system is in the initial operation stage, the control unit (8) controls to change the capacitance value of the capacitor circuit from the original Some of the first capacitance value is increased to the second capacitance value, and when the heat pump system reaches equilibrium, the control unit (8) controls to adjust the capacitance value of the capacitance circuit from the second capacitance value back to the original first capacitance value. A capacitance value. 8. A control method for a heat pump system according to any one of claims 5 to 7, characterized in that: the control unit (8) adjusts the capacitance value of the capacitance circuit according to the ambient temperature. 9. The control method of a heat pump system according to claim 8, characterized in that: the control unit (8) is pre-stored with a plurality of temperature ranges, each temperature range corresponds to a target capacitance value, and the control unit (8) (8) Acquiring the current ambient temperature, judging the temperature range in which the current ambient temperature is located, and controlling to adjust the capacitance value of the capacitance circuit to a target capacitance value corresponding to the temperature range. 10. A clothes dryer, characterized in that the clothes dryer has the heat pump system according to any one of claims 1-4.