Harmonics Mitigation in a Steel Industry Using 11-Level Cascaded Multilevel Inverter-Based DSTATCOM

Use of nonlinear loads in power distribution networks is expanding day by day, which results in the deterioration of the power quality of the system. An induction furnace (IF), which is an indispensable component of the steel industry, is one such typical example of a nonlinear load. It injects a considerable amount of harmonics into the supply network and consequently the performance of other loads in its vicinity gets affected. An 11-level cascaded multilevel inverter (CMLI)-based distribution static compensator (DSTATCOM) is implemented to mitigate the harmonic content of an IF in a steel plant. A Simulink model of an IF has been developed using experimental data obtained on-line from an industrial IF using a power quality analyzer. The solution methodology proposed using CMLI-based DSTATCOM reveals the effectiveness of the proposed control strategy for voltage sag mitigation and total harmonic distortion improvement of both load current and voltage as per the IEEE standards. The results obtained are also compared with that reported in the literature recently.