This paper presents the development of a single generator networked control system (NCS) to provide an experimental platform for cyber security studies on the power grid. The generator NCS is comprised of three main components: 1) a synchronous generator in a two-bus system, 2) a data acquisition (DAQ) unit, and 3) a controller connected in a local area network. The two-bus power grid consists of a LabVolt synchronous generator driven by a dynamometer serving as the prime mover, and the field circuit controlled by insulated gate bipolar junction transistor (IGBT) DC/DC chopper, transmission line, and load bank (resistor, capacitor, inductor). The DAQ unit is comprised of voltage and current transformers and op-amp circuits that are interfaced with an Arduino Uno microprocessor for analog-to-digital conversion (ADC) and further processing. The DAQ system sends the voltage and current data to the controller via the Ethernet link. The controller is implemented in software in a laptop and sends control signals to a separate Arduino which is then responsible for controlling the voltage applied to the field circuit of the synchronous generator. This is accomplished through the use of an IGBT chopper which is controlled by a pulse width modulated (PWM) voltage signal produced by the Arduino. Experimental results are presented that show the effects of cyber-attacks on a generator control system. A baseline for the behavior of the two-bus system is first established by operating the generator under various load conditions for which the controller maintains the desired terminal voltage. Then a series of data injection attacks (biasing and random data) and a Denial-of-Service attack were launched. With no attack prevention mechanism in place, the developed experimental platform provides a facility to observe and evaluate the impacts of various cyber-attacks on a real physical power generator.
