A New Topology for High Level Hybrid Cascaded Multilevel Inverter Motor Drive with Energy Storage and Power Distribution

Abstract

In this paper a new topology is proposed for energy storage and the power distribution using Ultracapacitors in cascaded multilevel inverters. This consists of hybrid cascaded multilevel inverter (HCMI) topologies and corresponding control strategies are applied to motor drive, interfacing both dc sources and capacitor energy storage elements. For high power motor drive application this proposed topology has a capability to produce high voltage at fundamental switching frequency makes it possible to use switches with low voltage and current ratings. The major advantages of this proposed control method are reduced switching loss, improved efficiency with less number of dc sources, elimination of harmonics and the ability of the capacitor voltage to be successfully maintained at the desired value when the machine is in transient state. In this paper a 7-level cascaded multilevel inverter with motor drive is considered. Finally, the simulation results validate the concept of this topology.

Segmented power distribution control system based on hybrid cascaded multilevel converter with parts of energy storage

“…Since storage capacitors are used to store regenerated energy when motor drives in deceleration, the capacitor's parameters are determined by the energy. The UC is selected owing to its small volume and highpower density leading to good dynamic performance [29][30][31].…”

“…In recent years, the hybrid asymmetrical cascade multilevel converters have attracted significant attention, which combine cells of different DC voltage ratings [20,21] and distinct topologies [22][23][24][25][26][27][28][29][30][31]. The main interest is to optimise the converter performance or to reduce the number of devices.…”

“…The main interest is to optimise the converter performance or to reduce the number of devices. To simplify the power supply, capacitors are applied to replace the DC sources of inverters constituting a variety of structures [24][25][26][27][28][29][30][31] such as the hybrid inverter with two-level three-phase inverter and H-bridges, three-level neutral-point-clamped (NPC) inverter and H-bridges or the CHB inverters with single energy source and multiple capacitors. The capacitors in [26,27] are only applied to provide harmonic cancellation, and those in [28] can only supply reactive power.…”

“…However, it only reduces one DC source, so the power supply is still complicated. Furthermore, a new control system based on the hybrid topology with one main inverter and several energy storage cells is proposed in [30, 31]. The energy storage has been designed not only to provide harmonic compensation, but also to be capable of recovering regenerative energy during the deceleration mode and reapplying the energy during acceleration.…”