Dynamic load management of domestic loads to assist with frequency response services in the UK

The UK is in the process of decarbonising energy sector as part of the Net Zero by 2050 commitment. Traditional generation that relies on the burning of fossil fuels is being phased out and replaced with low carbon generation such as wind and solar. Consequently there is likely to be a reduction in inertia on the UK’s power distribution network, which can make it harder to regulate the frequency. One of the solutions to regulate the frequency is to procure more balancing services, which would lead to an increase in expenditure on balancing services by National Grid. This thesis researches different methods of providing dynamic (changing continually to adjust to frequency conditions) frequency response through demand side management at domestic level.

A range of domestic appliances were tested to assess if they could be suitable loads for participation in this dynamic demand side response. The experimental work helped to quantify how much power could be available from domestic appliances. The research used this data to set a cost target for a power electronic interface that would adjust the voltage at a load, which in turn would control the power drawn by the load in response to the frequency. Different power electronics topologies were studied during this thesis. Two power electronic platforms; a Triac based and a chopper circuit were designed, modelled, built and tested at low voltage and at domestic grid voltage levels using a domestic appliance as a load. As the cost targets were very tight, low cost control techniques needed to be developed including novel analogue control using discrete components and low cost microprocessor control.

The analogue control with the Triac circuit was established to be the lowest cost method of allowing domestic appliances to undertake demand side response. This was produced at <£10 per device and is within cost targets for the response level obtained.