Advanced Electric Vehicle Car Park Control to Enable Grid Support

Future car parks will require significant power to support electric vehicle (EV) charging as there will be both an increase in the penetration of EV chargers and a higher demand for charging power as battery packs increase in capacity and users demand short charge durations. Effective control of the charging and local storage can be installed to help avoid excessive increases in electrical feeder capacity, however, car parks will inevitably attain significant power capability in the future compared to that seen today. It is therefore proposed in this research to leverage this power capability and use vehicle-to-grid charging, under the central control of the car park operator, to act as an aggregated energy storage system to deliver grid frequency response services. In this thesis, an agent-based model of a novel smart EV car park (SECP) is presented that can incorporate detailed power models for agents whilst providing a centralised command-based control structure to support advanced power flow management. It is first used to analyse how to manage the peak power demand of the EVs through charging management with four different power management methods proposed and evaluated. These methods are demonstrated to enable the power feeder to the SECP to be constrained whilst providing an equitable EV charging service. The thesis then investigates how photovoltaic panels and a battery energy storage system can be integrated into the SECP model to support improved EV charging. A methodology to control the power flow between the elements is presented and this is demonstrated to effectively increase the available power for EV charging and maximise the use of available PV energy over the day reducing the demand from the grid. The results show how the power feeder can be then minimised with the appropriate sizing of PV and the BESS. Finally, a power flow management strategy is proposed to enable the import and export of power to the grid to provide frequency response services as a single aggregated unit. Two frequency response services used by the Electricity System Operator in GB are simulated and it is validated that the SECP can deliver to the requirements of the services. A sizing methodology is proposed for the BESS to maximise service availability and EV charging capability whilst meeting the constraints of a power feeder limit. The research presented in this thesis transforms an EV car park from a burden on the grid to being effectively a short term energy storage system that can provide a fast power response to help balance the electrical transmission system.