Synchonizing phasor measurement and STATCOM controller in power system stability enhancement

<p>This paper presents the concepts of Synchronizing Phasor Measurement (SPM) and its application in addition with a STATCOM controller in order to enhance dynamic stability of a multi-machine power system. The bus voltage under consideration is estimated in the form of digital signal by a Synchronizing Phasor Measurement Unit (SPMU). The DSP based output of the SPMU is then applied to a fixed structure PI type lead-lag digital STATCOM controller. The performance of this discrete-time digital controller is compared with its analog counterpart. The parameters of the analog controller are first tuned with a popular soft computation technique, Particle Swarm optimization (PSO) and later this controller is converted to digital one for simulation with DSP based outputs received from SPMU. The effectiveness of the design of the proposed control scheme is illustrated through time domain simulation of a proposed 3-machine, 9-bus test power system. The simulation results established that the Synchronizing Phasor Measurement based digital control system is more effective and resulting better performance than the continuous-time analog control system in power system stability improvement<em>.</em></p>

DIGITAL CONTROL OF A CLOSED LOOP BUCK CONVERTER

The primary focus for the R&D in this area so far has been to figure out the best approach for evaluating and designing the DC-DC converter and perhaps the most appropriate control technique is being applied in different DC-DC converter circuits. Depending on power handling capacity as well as high-frequency switching, certain switching devices are chosen. This paper discusses the deployment of the digital PID controllers in the DC-DC converters. In an attempt to get a quicker response, voltage mode control has been used. Digital controllers started replacing traditional analog controllers more and more. Better immunity to changes in the environment which includes temperature and degradation of components, improved versatility by modifying the software, increasing advanced control methods, and decreased number of the components are the key benefits of the digital control against the analog control. A structured and concise strategy for designing a digitally operated close-loop Dc / Dc buck converter is discussed in this paper beginning with the Buck converter and giving the set of certain performance specification, implementations of the digital Proportional-IntegralDerivative(PID) controller is made. It addresses in depth all the appropriate DSP hardware and/or software methods and approaches needed to implement a controller. In order to illustrate the efficacy of the model, the dynamic response as well as the steady-state performance of controller is provided. The experimental outcomes fit well with the model of simulation. During the implementations of Switch Mode Power Supply (SMPS), application of dsPIC provides new perspectives towards affordable and versatile approaches of digital control.

MOBILE COMMUNICATIONS: A BEGINNERS GUIDE

In the beginning, voice channels were digitized and each voice channel was divided into time slots providing up to three simultaneous conversation on the same RF frequency thereby enhancing the number of channels by three times. The system was developed and introduced in 1990 and was known as IS 54B or also known as Digital AMPS or DAMPS. However the system still used analog control channels.