Research on Solar-Coupled Ground-Source Variable Frequency Air Conditioning System Based on TRNSYS

By building a model of air conditioning system with solar-coupled ground-source heat pump, the simulation shows that the pump has been running at its maximum load, especially in terms of energy consumption. In order to solve this problem, the variable frequency pump is adopted. Only the frequency conversion of the water pump at the load side and the water pump at the source side has been considered and the flow rate of the pump is determined according to the load value. The solar side water pump does not adopt frequency conversion to operate at the maximum flow, so as to ensure the maximum utilization of solar energy. When the load side water pump and the source side water pump adopt frequency conversion, this will not only cause a change in flow but also a power change of the unit, which will further affect the unit’s operating performance. On the other hand, based on the simulation results of the load, it indicates that the cooling capacity is greater than the heating capacity, which will cause the soil temperature to rise, that is, the soil temperature will be out of balance. Therefore, it is necessary to add a cooling tower to dissipate the pressure of the buried pipe in summer. The total energy consumption of the system is 22,411,541.00 kW, which is 27% less than the conventional energy consumption. In summer, the COP of the unit is about 6.9, which is 42% higher than the conventional situation. And in winter, the number is about 4.8, which is 27% higher than the conventional model.