Model Predictive Current Control Algorithm Based on Joint Modulation Strategy for Low-Inductance PMSM

Abstract

The disc coreless permanent magnet synchronous machine (PMSM) has many advantages. The inductance is far lower than that of the machines with the core structure. However, the general converter is designed for general machines. The current fluctuations are large when the low-inductance PMSM (LIPMSM) is driven by the general converter. To solve the above problem, the integrated design concept is adopted to design the converter, including the modulation algorithm, control algorithm, and the corresponding topology. The joint modulation strategy is proposed to increase the modulation frequency, which adjusts the output voltage by using the bus circuit and inverter circuit. The model predictive current control (MPCC) algorithm based on the joint modulation strategy is proposed, which has a small computational burden and high control accuracy. The most important feature of the proposed MPCC is that it has a modulation algorithm. To further reduce the current fluctuations, the bus voltage is adjusted in real time according to the bus voltage optimization algorithm. A new topology of the converter is designed to implement the algorithm function. Finally, the correctness and feasibility of the proposed method are verified. Compared with the general converter, the new one has a great improvement on the LIPMSM.