Aggregated control of electrical heaters for ancillary services provision

Aggregated control of large groups of electrical space heaters becomes possible under emerging smart communication and metering infrastructure. This paper explores the possibility of using coordinated control of such groups as a part of the virtual power plant portfolio for the purpose of ancillary services provision. The main focus is on secondary control service. Several control strategies are considered for the coordinating controller. It is shown that aggregate response of large groups of heaters can meet the requirements on secondary control under different control strategies. On the other hand the peculiar dynamics of aggregate response of a large group of thermostatically controlled electrical space heaters with its oscillatory character, direct feed-through and hysteretic nature of individual thermostats presents a challenge even for advanced control approaches like MPC. For this reason, there is a still long way to go before a fully implementable coordinating controller that has a real chance of being applied in practice is designed.