Using the Thermal Inertia of Trains for Contributing to Primary Frequency Control in Grids With Photovoltaic Generation

The participation on non-conventional generators imposes new challenges to power systems operation. Generators and consumers can participate on the provision of ancillary services. In literature, the role of consumers, by means of “demand response”, is not as developed as non-conventional generators contributions. This work explores the contribution of railway systems, a world-wide expanding load, to primary frequency control of power systems with high share of photovoltaic generation. The thermal inertia of trains is used to provide frequency control from onboard heating, ventilation, and air conditioning (HVAC) systems. The benefits of combining HVAC systems demand response and photovoltaic generators are assessed. In addition, the new concept of relieving non-conventional generation from frequency control tasks is introduced. To validate the approach, a multi-scenario case study is carried out. Results show the capability of using train HVAC systems to provide frequency control and to cooperate with the frequency control provision by photovoltaic generation.