The Optimized Design of a NPC Three-Level Inverter Forced-Air Cooling System Based on Dynamic Power-loss Calculations of the Maximum Power-Loss Range

Abstract

In some special occasions with strict size requirements, such as mine hoists, improving the design accuracy of the forced-air cooling systems of NPC three-level inverters is a key technology for improving the power density and decreasing the volume. First, a fast power-loss calculation method was brought. Its calculation principle introduced in detail, and the computation formulas were deduced. Secondly, the average and dynamic power losses of a 1MW mine hoist acting as the research target were analyzed, and a forced-air cooling system model based on a series of theoretical analyses was designed with the average power loss as a heat source. The simulation analyses proves the accuracy and effectiveness of this cooling system during the unit lifting period. Finally, according to an analysis of the periodic working condition, the maximum power-loss range of a NPC three-level inverter under multi cycle operation was obtained and its dynamic power loss was taken into the optimized cooling system model as a heat source to solve the power device damage caused by instantaneous heat accumulation. The effectiveness and feasibility of the optimization design based on the dynamic power loss calculation of the maximum power-loss range was proved by simulation and experimental results.

Power Device Thermal Fault Tolerant Control of High-Power Three-Level Explosion-Proof Inverter Based on Holographic Equivalent Dual-Mode Modulation

“…Simulation analysis of power losses in the same bridge 1 and its anti-parallel diode in NPC three-level explosion-proof inverter, based on two kinds of holographic equivalent mode, can be obtained in accordance with [14][15][16][17]. The simulation results are as shown in Figure 9.…”

“…The experiment platform is shown in Figure 7, including motor part and inverter part [14][15][16][17]. The parameters of winding asynchronous motor and component parameters of inverter main circuit are shown in Tables 3 and 4, respectively.…”

A Hierarchical Model Predictive Voltage Control for NPC/H-Bridge Converters with a Reduced Computational Burden

“…These advantages make these multilevel converters very popular and efficient solutions to medium/high-voltage and high-power applications [2]- [9]. They have been widely employed in high-power drives [2], [3], high-voltage direct-current (HVDC) transmissions [4], [5], active power filters (APF) [6], static synchronous compensators (STATCOM) [7] and other industrial applications [8], [9] in the past decades.…”