Voltage sensorless control algorithm for power quality improvement in distribution network

In this paper, a voltage sensorless control algorithm based on voltage estimators is used to control the DSTATCOM (Distribution Static Compensator) for a three phase four wire distribution system. The control algorithm emulates the load and DSTATCOM collectively as a balanced resistive load on the supply system. This algorithm functions as an estimator and eliminates the voltage sensor requirement. This algorithm is derived for a modified topology of DSTATCOM in the system which advantages are described in this paper. Due to simplicity of the algorithm, it can be easily implemented with reduced calculation than other complex algorithms. This algorithm is very effective in mitigating the various power quality problems like large neutral current due to unbalanced or nonlinear loads, reactive power consumption, harmonics current injection, voltage regulation in the distribution system.