Latencies in Power Systems: A Database-Based Time-Delay Compensation for Memory Controllers

Abstract

Time-delay is inherent to communications schemes in power systems, and in a closed loop strategy the presence of latencies increases inter-area oscillations and security problems in tie-lines. Recently, Wide Area Measurement Systems (WAMS) have been introduced to improve observability and overcome slow-rate communications from traditional Supervisory Control and Data Acquisition (SCADA). However, there is a need for tackling time-delays in control strategies based in WAMS. For this purpose, this paper proposes an Enhanced Time Delay Compensator (ETDC) approach which manages varying time delays introducing the perspective of network latency instead dead time; also, ETDC takes advantage of real signals and measurements transmission procedure in WAMS building a closed-loop memory control for power systems. The strength of the proposal was tested satisfactorily in a widely studied benchmark model in which inter-area oscillations were excited properly.

Effects of Communication Signal Delay on the Power Grid: A Review

“…Normally, communication delays can range from several microseconds to hundreds of milliseconds [40,75,88,89]. Moreover, according to some other reports [62,86], the normal 150 to 300 milliseconds of telecommunications are considered to be the plans to perform actual transient stability control system, stability index, fault clearance time and delay in response. In this work, a lot of simulation is done with different values of delay.…”

“…In reference [16,62], the authors discussed the effects of time-delays in WAMS-based monitoring activities on the performance of the system [63]. Molina-Cabrera A et al demonstrated the ETDC, which uses a delay method to differentiate a line delay method rather than a deadline; moreover, the ETDC uses real-time signals and how to send measurements to WAMS that builds a closed-loop database system [62].…”

“…In reference [16,62], the authors discussed the effects of time-delays in WAMS-based monitoring activities on the performance of the system [63]. Molina-Cabrera A et al demonstrated the ETDC, which uses a delay method to differentiate a line delay method rather than a deadline; moreover, the ETDC uses real-time signals and how to send measurements to WAMS that builds a closed-loop database system [62]. In [64], the authors deliberated the combination of power control and communication in network control which yields interesting results in the design, and they reported that because the analytical approach is not feasible in the form of a robust system, the paper also prepares a new general method for calculating the system's eigenvalues and various delays that cannot be explained by the analysis of possible objects.…”

“…Table 5 shows the statistical delays in the various studies conducted in the reference paper. The maximum delay to be assessed is 500 ms [62,83].…”

Grid-Connected Renewable Energy Sources

“…Two papers discuss the issues related to the time framework. In article [2], the enhanced time delay compensator approach manages varying time delays inherent to communications schemes in power systems. This introduces the perspective of network latency instead of dead time.…”