Control method during heating starting of air source heat pump

Abstract

The invention relates to a control method during heating starting of an air source heat pump, which comprises a heat pump unit, an environment temperature sensor, a water inlet temperature sensor and an outer coil pipe temperature sensor, and the control method comprises the following steps: in an acquisition stage, the heat pump unit acquires downtime t1 and sets a downtime judgment value t1; the environment temperature sensor collects the environment temperature T1, and the heat pump unit sets an environment temperature judgment value T1; the water inlet temperature sensor collects the water inlet temperature T2, and the heat pump unit sets a water inlet temperature judgment value T2; an outer coil pipe temperature sensor collects an outer coil pipe temperature T3, and a heat pump unit sets an outer coil pipe temperature judgment value T3; the heat pump unit records defrosting operation time t2 and sets a defrosting time judgment value t2; the control stage is divided into six steps. The method has the advantages that defrosting operation is performed firstly after the unit is started for heating, lubricating oil deposited on the evaporation side is quickly sucked back to the compressor, and reliable operation of oil return is ensured when the compressor is started.

Description

Technical Field

[0001] The invention relates to a control method for starting an air source heat pump for heating. Background Art

[0002] After the air source heat pump unit is shut down due to low ambient temperature and high water temperature, the mixture of refrigerant and oil usually migrates and deposits to the low-temperature side evaporator. When the unit is turned on again for heating after a long shutdown time, the compressor usually lacks oil in the initial startup. The current solution is generally to use a low-frequency platform operation when the compressor is started to reduce the amount of oil discharged in the initial stage of compressor startup. Although this method can reduce the amount of oil discharged from the compressor, the amount of lubricating oil returning to the compressor is also less. After running for a period of time, the compressor is still short of oil. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a control method for the start-up of an air source heat pump heating system. The method first enters the defrost operation after the unit is turned on for heating, and quickly absorbs the lubricating oil deposited on the evaporation side back to the compressor, ensuring reliable oil return operation when the compressor starts.

[0004] In order to achieve the above object, the present invention is implemented as follows: it is a control method for starting an air source heat pump heating system, comprising a heat pump unit, an ambient temperature sensor, a water inlet temperature sensor and an external coil temperature sensor, and the control method is as follows: Collection phase Step 1, the heat pump unit collects the downtime t1 and sets the downtime judgment value △t1; the ambient temperature sensor collects the ambient temperature T1 and sets the ambient temperature judgment value △T1 for the heat pump unit; the water inlet temperature sensor collects the water inlet temperature T2 and sets the water inlet temperature judgment value △T2 for the heat pump unit; the external coil temperature sensor collects the external coil temperature T3 and sets the external coil temperature judgment value △T3 for the heat pump unit; the heat pump unit records the defrost operation time t2 and sets the defrost time judgment value △t2; Control Phase Step 1: Start the heat pump unit; Step 2: The first power-on time of the heat pump unit is t3. When t3≥△t1 or t1≥△t1, then go to step 3, otherwise go to step 6; Step 3: When T1≤△T1 and T2≥△T2, go to step 4; otherwise, go to step 6; Step 4: The heat pump unit enters the defrosting stage and proceeds to step 5; Step 5: When T3≥△T3 or t2≥△t2, go to step 6, otherwise go to step 4; Step 6: The heat pump unit enters the heating stage.

[0005] In the present technical solution, the △t1≥4h.

[0006] In the present technical solution, the ΔT1≤3°C.

[0007] In the present technical solution, the ΔT2 ≥ 20°C.

[0008] In the present technical solution, the ΔT3 ≥ 17°C.

[0009] The advantages of the present invention compared with the prior art are as follows: the method enters defrosting operation first after the unit is turned on for heating, and the lubricating oil deposited on the evaporation side is quickly sucked back to the compressor, ensuring reliable oil return operation when the compressor starts. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a flow chart of the control phase of the present invention. DETAILED DESCRIPTION

[0011] The specific embodiments of the present invention are further described below in conjunction with the accompanying drawings. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0012] In the description of the present invention, the terms "upper", "lower", "top" and "bottom" indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention.

[0013] In the present invention, unless otherwise clearly specified and limited, the terms "set", "connected", "located" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or a detachable arrangement or integration; it can be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium, which can enable the internal connectivity of two elements or the interaction relationship between the two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0014] like Figure 1 As shown, it is a control method for starting the air source heat pump heating, which is characterized by including a heat pump unit, an ambient temperature sensor, a water inlet temperature sensor and an external coil temperature sensor. The control method is as follows: Collection phase Step 1, the heat pump unit collects the downtime t1 and sets the downtime judgment value △t1; the ambient temperature sensor collects the ambient temperature T1 and sets the ambient temperature judgment value △T1 for the heat pump unit; the water inlet temperature sensor collects the water inlet temperature T2 and sets the water inlet temperature judgment value △T2 for the heat pump unit; the external coil temperature sensor collects the external coil temperature T3 and sets the external coil temperature judgment value △T3 for the heat pump unit; the heat pump unit records the defrost operation time t2 and sets the defrost time judgment value △t2; Control Phase Step 1: Start the heat pump unit; Step 2: The first power-on time of the heat pump unit is t3. When t3≥△t1 or t1≥△t1, then go to step 3, otherwise go to step 6; Step 3: When T1≤△T1 and T2≥△T2, go to step 4; otherwise, go to step 6; Step 4: The heat pump unit enters the defrosting stage and proceeds to step 5; Step 5: When T3≥△T3 or t2≥△t2, go to step 6, otherwise go to step 4; Step 6: The heat pump unit enters the heating stage.

[0015] It effectively solves the problem that the compressor is prone to oil shortage when the air source heat pump unit with low ambient temperature and high water temperature is restarted after being shut down for a period of time, and ensures reliable operation of oil return when the compressor starts.

[0016] In this embodiment, Δt1≥4h.

[0017] In this embodiment, the ΔT1≤3°C.

[0018] In this embodiment, the ΔT2 ≥ 20°C.

[0019] In this embodiment, the ΔT3 ≥ 17°C.

[0020] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and deformations of these embodiments without departing from the principles and purposes of the present invention still fall within the scope of protection of the present invention.

Claims

1. A control method for starting an air source heat pump for heating, characterized in that Including heat pump unit, ambient temperature sensor, water inlet temperature sensor and external coil temperature sensor, the control method is as follows: Collection phase Step 1, the heat pump unit collects the downtime t1 and sets the downtime judgment value △t1; the ambient temperature sensor collects the ambient temperature T1 and sets the ambient temperature judgment value △T1 for the heat pump unit; the water inlet temperature sensor collects the water inlet temperature T2 and sets the water inlet temperature judgment value △T2 for the heat pump unit; the external coil temperature sensor collects the external coil temperature T3 and sets the external coil temperature judgment value △T3 for the heat pump unit; the heat pump unit records the defrost operation time t2 and sets the defrost time judgment value △t2; Control Phase Step 1: Start the heat pump unit; Step 2: The first power-on time of the heat pump unit is t3. When t3≥△t1 or t1≥△t1, then go to step 3, otherwise go to step 6; Step 3: When T1≤△T1 and T2≥△T2, go to step 4; otherwise, go to step 6; Step 4: The heat pump unit enters the defrosting stage and proceeds to step 5; Step 5: When T3≥△T3 or t2≥△t2, go to step 6, otherwise go to step 4; Step 6: The heat pump unit enters the heating stage.

2. The control method for starting the air source heat pump heating according to claim 1, characterized in that The △t1≥4h.

3. The control method for starting the air source heat pump heating according to claim 1, characterized in that The △T1≤3℃.

4. The control method for starting the air source heat pump heating according to claim 1, characterized in that The ΔT2≥20°C.

5. The control method for starting the air source heat pump heating according to claim 1, characterized in that The ΔT3≥17°C.

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