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A big step forward to improve power system monitoring and performance, continued load growth without a corresponding increase in transmission resources has resulted in reduced operational margins for many power systems worldwide and has led to operation of power systems closer to their stability limits and to power exchange in new patterns. These issues, as well as the on-going worldwide trend towards deregulation of the entire industry on the one hand and the increased need for accurate and better network monitoring on the other hand, force power utilities exposed to this pressure to demand new solutions for wide area monitoring, protection and control. Wide-area monitoring, protection, and control require communicating the specific-node information to a remote station but all information should be time synchronized so that to neutralize the time difference between information. It gives a complete simultaneous snap shot of the power system. The conventional system is not able to satisfy the time-synchronized requirement of power system. Phasor Measurement Unit (PMU) is enabler of time-synchronized measurement, it communicate the synchronized local information to remote station.

The electrical power system is not a simple thing it’s a complex man-made system so it has many problems where as on the other end, it should reliable and supply electrical energy continuously without any interruption. There should be no blackout and outage [

This technology has been made possible by advancements in computer and processing technologies and availability of GPS signals. We are rapidly approaching an era where all metering devices will be time synchronized with high precision and accurate time tags as part of any measurement. To achieve the potential benefits, advancements in time synchronization must be matched by advancements in other areas. One example is data communications, where communication channels have become faster and more reliable in streaming PMU data from remote sites to a central facility. Improvements in instrument transformers (such as optical transducers) are important for the quality of the signals supplied to the PMU. A third area is in developing applications, i.e., software that operates on the data provided by the PMUs. Although academia, vendors, utilities, and consultants have developed a large number of methods and algorithms and performed system analysis and studies to apply the technology, like any other advanced tool, PMUs are good only in the hands of trained users. The technology exists today to bring the PMU information into the control centers located at remote area and present it to the operators in a graphical format. In this paper we discuss this advanced technology (PMUs) with the help of MATLAB simulation. We design this PMU model in MATLAB SIMULINK and then we installed this model in the start and end of transmission line in our sample simulation of a small power system in SIMULINK. This all is for testing of its testing valuation. Such application is made for the protection, monitoring and control of wide power system. And this paper also discusses our related research work to this subject.

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In this paper we introduce the PMU’s simulation in MATLAB and we integrated PMU in a simple power system. We derived the mathematical model and did simulation in MATLAB/SIMULINK.

PMU Mathematical ModelFollowing mathematical model is used to calculate the magnitude and phase angle of currents and voltages.

These equations are represented below:

Now for real part:

Now

Put Equations (2) and (3) in Equation (1)

For imaginary part:

Put Equations (5) and (6) in Equation (4) so

Now for magnitude and phase angle:

In this mathematical model we calculated real and imaginary part separately and then from it we calculated magnitude and phase

Figures 4-6 are the sub-system of load consisting domestic, commercial and industrial respectively.

PMUs create a picture showing the stability status of the nodes in the monitored area. PMUs take this picture at the same reference time. Using real-time information from PMUs and automated controls to predict, identify, and respond to system problems; a smart grid can automatically avoid or diminish power outages, power quality problems and supply disruptions.

A Phasor network consisting of PMUs spread throughout the power system, PDC collect the information from PMUs and GPS time stamping can provide a theoretical accuracy of synchronization better than 1 microsecond. “Clocks need to be accurate to ±500 nanoseconds to provide the one microsecond time standard needed by each device performing SynchroPhasor measurement.” For 50 Hz systems, PMUs must deliver between 10 to 30 synchronous reports per second depending on the application. The PDC correlates the data, controls and moni-

tors the PMUs (from a dozen up to 60) .

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