The economic strains on the deregulated electricity market have taken the grid closer to the system’s limits and components. The Synchronized Phazor Mess technology has been the ideal way of monitoring and controlling power systems, particularly under stress conditions. Based on phasers from PHMUs obtained in real time at 50 or 100 Hz, quick and accurate status estimating and assessment of stability risks and margins is now feasible for a wide-speed measuring device (WAMS), as well as preventive and correctional control steps. However, the number of PMUs is limited for the actual, requested data for communication, storage and processing, and only the main nodes in WAMS must be monitored. Previous research was therefore focused on optimizing the location of PMUs and integrating SCADA and WAMS data.

As the ancestor of WAMS, SCADA is a widely used method of monitoring. In general, a SCADA consists of a control center master station and a set of RTUs in substation and energy plants. SCADA has been installed at a control center. RTUs calculate voltage, current, frequency and compute active and reactive power at every substation and factory. Those data are transmitted through a communication network to the SCADA master station in the control center. The large number of substations and power plants to track as well as the limitation on a small bandwidth of communication can be modified with a 3/4 s interval. It is normally too slow to record dynamics of the system during disturbances. The SCADA ‘s prevalence is strongly preferred to encourage the SCADA to represent the current infrastructure-based system dynamic, so the dispatchers in the control center, however, can easily detect the oscillation and act on schedule, even if they are 3-4s delayed. In recent years this has become a feasible objective with a much improved SCADA power. First of all, RTUs have the technological feasibility of collecting phasers from electronic instruments transducers inside a substation by the advent and development of the automated substation automation system using IEC 61850. Secondly, the widespread use of optic fiber has greatly strengthened SCADA’s communication capacity, although a communication bandwidth of between 50 and 100Hz is still overwhelmed. There is, therefore, a limit to the amount of information to be sent from the RTUs to the SCADA server, and the complexities of the system on a basis of the current infrastructure may be mirrored.

For automation enginner please send email: upport