Onsite Tests of Controlling a Large Constant Speed Centrifugal Chiller for Grid Frequency Regulation

High penetration of intermittent renewables may cause safety and stability problems to the electricity grid. Building HVAC systems could contribute to grid frequency regulation. Constant speed centrifugal chillers have rarely been studied for grid frequency regulation. A control strategy is proposed to control constant speed centrifugal chillers to follow grid regulation signals. It is proposed to regulate the chiller power consumption by dynamically limiting its power consumption and resetting its supply chilled water temperature. Onsite tests were conducted to find critical parameters. The total delay time in chiller power was about 20–25 seconds. And the maximum ramping speed of chiller power was 2.53 kW/s. When providing a regulation capacity of 100 kW (7.46% of the rated chiller power), the composite performance scores were 0.901 and 0.885 for Regulation A test and Regulation D test, respectively.