Experimental verification of power fluctuation compensation in microgrid by use of heat pump air conditioning system

To reduce the necessary capacity of energy storage systems (ESSs) for power fluctuation compensation, the concept of load control has been proposed. In this paper, heat pump air conditioning unit is treated as controllable load. Verification experiment of heat pump power consumption control has been conducted using model microgrid with gas engine(GE) and Nickel Metal Hydride (NiMH) battery. The fastest part of the power fluctuation is compensated by NiMH battery, and the slowest part of the power fluctuation is compensated by GE. The heat pump is used for compensation of mid-range power fluctuation. The control system was designed to keep the tie line power flow of the microgrid to a constant value. In the experiment, the fluctuation of the tie line power flow was small compared to that of load demand in microgrid. The result of the experiment suggests that heat pump has enough response speed and control of heat pump´s power consumption as controllable load is effective for power fluctuation compensation.