Simulation and analysis of a grid integrated distribution system based on LMS algorithm for hybrid types of load

This paper analyzes an adaptive control based Least Mean Square (LMS) algorithm in three phase grid integrated distribution system. This LMS control technique is utilized to alleviate the problems related to power quality, generated by different non-linear types of load and also by solid state equipments. The analysis of distribution static compensator (DSTATCOM) based distribution system has been carried out for various types of load viz. linear and hybrid types of load so as to achieve the improved power quality. Initially the performance was analysed for hybrid load (a combination of linear and non-linear load), and discussed the variation of harmonic content in source current with load power factor, and found minimum at a particular value of load power factor. The source current THD has been observed as 8% at 0.6 power factor load, while it decreases to 5.7% at 0.95 power factor load, maintaining the better quality waveform. It can be suggested that the load having more and more power factor is preferred in distribution system so as to maintain the power quality at its standards level. Moreover, the active and reactive power flow from source/compensator towards load and filter has also been examined. For instance, at 0.95 power factor, grid supplies an active power of 15 kW, and the power consumed by the load and filter is 26.8 kW and 50 W respectively. Consequently, the extra required power has been supplied by the compensator itself. Later, the non-linear load has been removed and the performance was judged for only linear RL load so as to analyze the effects of non-linear load connected at PCC. The source current THD has further reduced to 7.1% at 0.6 power factor and 5.3% at 0.95 power factor, observing the less value than that of the obtained results in case of hybrid load. Hence, it is concluded that the obtained results of THD, from the simulation for linear and hybrid types of load, falls within the permissible limit and hence improves the power quality. A comparison has also been presented for both the cases. The analysis was done in Sim-power system toolbox of Matlab/Simulink software and the obtained results of THD, source and load powers have been represented in tabular form and elaborated graphically.