Improved Power Quality of Distribution Grid by integrating DVR with Super Twisting Sliding Mode Control

Abstract

The increase of sustainable energy sources and integration with the power distribution grid produced power quality (PQ) problems such as voltage sag and voltage swell. These problems are produced in the power distribution systems due to multiple reasons that affect sensitive loads. Voltage sag and voltage swell mostly occurring Power quality complications in the power system. These power quality issues in the power distribution system can be mitigated by using custom power devices, Dynamic Voltage Restorer (DVR) is the newly introduced device. Different techniques and algorithms have been used to mitigate these problems. In this research work, an ultra-capacitor-based DVR and a super-twisting sliding mode controller are used for the said problem. The addition of energy storage, such as an ultra-capacitor, to a dynamic voltage restorer, creates a voltage that can alleviate voltage issues such as sag and swell. For both the voltage sags and voltage swells, a high voltage is necessary for a short spell. A dynamic voltage restorer is an apparatus that is linked between the voltage source and the load side using an injection transformer to input voltage into the power distribution side to remedy a problem that has a significant impact on the load voltage. With the inclusion of a dynamic voltage restorer and sliding mode controller, the system will be able to fix PQ issues such as voltage sag and swell on its own, rather than relying on the grid as in past years. MATLAB/Simulink R2018a has been used to conduct simulation studies. Simulation studies have demonstrated that the proposed scheme is more effective, simple, robust, and more flexible and has a better mitigation time of 2.5 milliseconds and a total harmonic distortion of less than 5% as per IEEE standards.