Method for controlling constant heat flow in ground source heat exchanger heat transfer performance test

Abstract

The invention discloses a method for controlling constant heat flow in a ground source heat exchanger heat transfer performance test, which is characterized in that: a heat pump unit for generating cold water in the test is a fixed frequency compressor, and a silicon controlled controller is used for controlling electric heating power; the refrigerating power of a heat pump is calculated according to the temperatures and flow rates of water at the inlet and outlet of the heat pump and is compared with the set heat exchange quantity of a ground source heat pump soil heat exchanger; and when the refrigerating power of the heat pump is unequal to the set value, the output current of the silicon controlled controller and the heating quantity of an electric heater are changed, so that cold water heat flow entering the soil heat exchanger is constant. The temperatures of the water at the inlet and outlet of the heat exchanger are acquired by a temperature sensor; electric heating output power is adjusted according to an algorithm; control accuracy and response speed are high; corresponding control programs can be combined with the ground source heat pump heat exchanger heat transfer performance test program to be operated simultaneously; and the requirement of the constant heat flow in the ground source heat pump heat exchanger heat transfer performance test is fully met.

Description

technical field [0001] The invention relates to a method for controlling constant heat flow in the heat extraction performance test of a ground source heat pump heat exchanger. Background technique [0002] The use of ground source heat pumps that use surface soil or water as a cold / heat source to provide heating and cooling for buildings has become a technical hotspot in building energy conservation at home and abroad in recent years. The heat transfer performance and operational reliability of ground source heat exchangers are the key to the success of this energy-saving technology. Since the geological composition, hydrological characteristics, physical characteristics and other parameters of the surface are different, the corresponding heat transfer performance will change accordingly, so the heat transfer performance of ground source heat exchangers buried in different regions will be different. Engaged in the design of ground source heat exchangers, especially for lar...

AI Technical Summary

Problems solved by technology

In actual use, when the ambient temperature of the heat pump unit, that is, the condensing temperature changes, the cooling capacity of the heat pump unit will change, resulting in a change in the heat flow supplied to the underground heat exchanger cold water, which cannot meet the heat extraction performance test of the ground source heat pump heat exchanger. The condition of constant heat flow required in

Some test devices use variable frequency compressors, which can change the cooling capacity by changing the compression capacity of the compressor, but this method is costly, complicated to control, and the accuracy cannot be controlled by humans. There are many changing factors and cannot fully achieve the purpose of constant heat flow.

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