Cyber-physical testbeds for smart grid and electric vehicle-charging infrastructure

Abstract

To enhance the reliability, resiliency and sustainability of a microgrid (MG) in the presence of several distributed energy resources (DERs) and loads, communication systems play a vital role, forming it into a cyber-physical system (CPS). However, integration of information and communication technology (ICT) in the MG architecture exposes MG to potential malicious cyber attacks as well. Similarly, electric vehicles (EVs) also come with a host of many cybersecurity risks. The integration of power, communication and transportation sectors empowers the intruders to exploit the vulnerability and disrupt the operation of multiple sectors. Testbed plays a vital role in the study of the threat landscape and the impact of cyber attacks (such as denial of service (DoS) attacks and false data injection attacks (FDIA)) in such cyber-physical infrastructure. This study would further aid to develop and verify the detection and mitigation schemes against cyber attacks.This work presents a detailed study on the development of real-time (RT) cosimulation testbed for inverter-based MG and RT testbed for EV-charging infrastructure. The MG testbed consists of OP5700 RT simulator to emulate cyber-physical layer through HYPERSIM software; and SEL-3530 Real-Time Automation Controller (RTAC) hardware configured with ACSELERATOR RTAC SEL-5033 software. A human-machine interface (HMI) is further developed in ACSELERATOR Diagram Builder SEL-5035 software for local/remote monitoring and control. Furthermore, communication protocols such as Modbus, sampled measured values (SMVs), generic object-oriented substation event (GOOSE) and distributed network protocol 3 (DNP3) on an Ethernet-based interface were established to link the cyber and physical layers. Furthermore, the testbed for EV-charging infrastructure consists of AC and DC emulators to emulate the respective charging station (AC/DC) and EV. It also constitutes various charging cables supported for different charging protocols such as combined charging system (CCS), GB/T and CHAdeMO. To monitor the message exchanges, charging discovery system (CDS) hardware along with its software is used. Few of the test cases have been presented to demonstrate the ability of these testbeds.