Development of a novel Underfrequency Relay and Energy Storage Controller for Underfrequency Protection

Abstract:
In a project, funded by the German Federal Ministry for Economic Affairs and Energy, a novel underfrequency relay and Storage Controller was developed. To ensure a selective load shedding scheme, the relay can be installed at secondary substations or directly at consumer’s side. The Storage Controller is able to control an inverter of a battery energy storage system via a serial communication interface to provide positive and negative primary control. In this paper, a field test is described in which the devices are tested over five months. For this purpose, the devices and battery energy storage systems are installed at three different locations in a real network. The main objective is to evaluate the communication infrastructure between the installed components and the system operator, and the reliability implemented on the frequency control algorithms of the developed underfrequency relay and Storage Controller.