Reparation of voltage disturbance using PR controller-based DVR in Modern power systems

Abstract

The Smart Grid environment gives more benefits for the consumers, whereas the power quality is one of the challenging factors in the smart grid environment. To protect the system equipment and increase the reliability, different filter technologies are used. Even though, consumers’ expectations towards the power quality are not fulfilled. To overcome these drawbacks and enhance the system reliability, a new Custom Power Devices (CPD) are introduced in the system. Among different CPDs, the Dynamic Voltage Restorer (DVR) is one of the voltage compensating devices that is used to improve the power quality during distortions. When the distortions such as voltage swell and sag occur in the distribution system, the control strategy in the DVR plays a significant role. In this article, the DVR performance using Proportional Integral (PI), Proportional Resonant (PR) controllers are analyzed. A robust optimization algorithm called Self Balanced Differential Evolution (SBDE) is used to find the optimal gain values of the controllers in order to reach the target of global minimum error and obtain fast response. Then, a comparative analysis is performed between different controllers and verified that the performance of PR controller is superior than the other controllers. It has been found that the proposed PR controller strategy reduces the Total Harmonic Distortion (THD) values for all types of faults. The proposed SBDE optimized DVR with PR controller reduces the THD value less than 4% under voltage distoration condition. The DVR topology is validated in MATLAB/SIMULINK in order to detect the disturbance and inject the voltage to compensate the load voltage.

Dynamic Voltage Restorer as a Solution to Voltage Problems in Power Systems: Focus on Sags, Swells and Steady Fluctuations

“…The PI theory has also formed the basis of designing several controllers for DVRs. To mitigate voltage swell and sag, Danalakshmi et al [66] studied the feasibilities of various PI and proportional resonant (PR) controllers for use in DVR control and assessed the performance of these controllers in detecting disturbances and injecting voltage to compensate for load voltages under these disturbances. Elkady et al [68] presented an enhanced, optimised and less complex PI controller, which was implemented in a dq synchronous rotating reference frame, for a DVR that can enhance transient, steady-state and dynamic responses of the DVR scheme and eliminate inherent transient oscillations.…”

A New Technique Implemented in Synchronous Reference Frame for DVR Control Under Severe Sag and Swell Conditions

“…One significant disadvantage of the nonlinear controller is that derivative operations can create issues with electromagnetic interference on inverter switching, resulting in substantial control errors. actually, a high pass filter can be used to substitute the derivative behavior, which improves performance while attenuating high frequency noise in sensors and cables [35], [38].…”

Research on the control strategy of LCL grid-connected inverters based on improved auto disturbance rejection

“…By setting the fundamental frequency point, the PR controller has sufficient gain at the fundamental frequency point while the gains at other points remain unchanged, thus achieving accurate and error-free tracking of the fundamental wave of the AC signal. [17][18][19][20] But the control frequency band of the PR controller is narrow and it can only achieve sufficient gain at a fixed frequency. 11 Negi et al 21 used the PR controller to realize an improved damping strategy that has enough stability margin, but requires an accurate model of the system and high online computational requirements.…”