Wide‐area monitoring and control using the real time digital simulator and a synchrophasor vector processor

Abstract

SUMMARYSeveral major blackouts in the past have shown the need for advanced wide-area monitoring and control (WAMC) techniques. Advanced synchrophasor visualization and monitoring can be realized with timereferenced power system data that are collected by phasor measurement units (PMUs) using synchronized clocks. Presently, PMUs are being deployed around the world at a rapid rate for various power system applications. When a necessary number of PMUs are installed at optimal locations throughout the network, the complete state of the system can be observed. PMUs take real-time measurements to determine the state of the power system and can be used to enhance state estimation efficiency. With PMUs in place, there are many control and protection schemes that can be implemented successfully to take preventive and corrective actions. These remedial action schemes (RASs) are classified by the IEEE Power System Relaying Committee (PSRC) as system integrity protection schemes (SIPSs). This work involved the development of a real-time hardware test bed in order to analyze the transient stability of a simulated power system by using synchrophasors to visualize system stress across a transmission line with and without load-shedding schemes. The real time digital simulator (RTDS 1 ) was used to model the power system in real time. PMUs, a satellite-synchronized clock, and a synchrophasor vector processor (SVP) were used to test the synchrophasor application.

Power system measurement data and their applications

“…Srivastava et al [3] describe in their paper a PMU laboratory in which a power system is emulated by a real-time digital simulator (RTDS). They use the laboratory facility to demonstrate a wide-area monitoring and control (WAMC) system in which an angle difference is used to activate load shedding to preserve system stability.…”

Event stream processing for improved situational awareness in the smart grid

“…RTDS is a real-time power system simulator that performs digital electromagnetic transient simulation of electric power circuits using a time step as small as 2 ls (Srivastava, Ravikumar, & Zweigle, 2010). The real-time operation of the RTDS makes it suitable for development and testing of protection and control techniques for power systems.…”

“…RSCAD is used to design the power system circuits which can be loaded into RTDS. The RTDS at Mississippi State University consists of a cubicle with two processor racks, containing eight Triple Processor Cards and two Giga Processor Cards (GPCs) (Srivastava et al, 2010).…”

Observability of nonlinear power system dynamics using synchrophasor data

“…Therefore, the average value of observability indices for all data points along the trajectory of x(t) is used as the base value, denoted by r base . The observability index is normalized by the base value r ¼ r=r base (11) In the test cases of this study, the value of 0.01 is chosen as the threshold value for the normalized observability index. The threshold value is system specific and will require numerical testing.…”

“…It is also noticed that even with same PMU numbers, the system can have different levels of observability. Consider a different 15-PMU placement scheme with PMUs at generator buses 1,2,5,6,7,8,9,10,11,12,15,16,22, 24 and 28. The system observability indices of the new placement scheme (scheme 2) are shown in Figure 10.…”