Improved Trans-Z-Source Network with high boost for Active-Neutral-Point-Clamped Inverter

A novel Z-source network using coupled inductor is presented in this paper for neutral point clamped voltage source inverters. Proposed topology combines the advantages of Z-source network with coupled inductor and active-neutral-point-clamped three-level (ANPC-3L) topology. The coupled inductor-Z-Source ANPC inverter provides a high boost factor and avoids the problem of short-circuiting the input supply with leakage inductance of the windings in coupled inductor. A wide output voltage range can be obtained by regulating the turn ratio, time period for shoot-through and modulation index. Various operation modes, voltage relationships, switching signal generation and modulation technique used are explained in detail. For modulation of trans-Z-Source network simple boost control technique is used and carrier-based space vector modulation for ANPC inverter. MATLAB simulation on a 2kW, 400V scalar controlled three-phase IM drive is done to validate the working of the proposed topology.