Simulation of m-phase active voltage rectifier with space-vector modulation

Abstract

The autonomous power supply system (APSS) from synchronous magnetoelectric generator and active voltage rectifier (AVR) maximally meets the requirements of the minimum specific mass and the complete coordination of the primary electric power source with the load. With multiphase (m > 3) execution of the electric machine, it is possible to obtain a trapezoidal electromotive force (EMF) and increase the specific power conversion provided that the EMF and the current at the output of the m-phase generator are fully matched. Therefore, the aim of the work is to synthesize the space-vector modulation (SVM) algorithm of the active voltage rectifier to fully match the primary source of electrical energy with the load under the condition of a trapezoidal EMF of the generator. Synthesis of the PVM algorithm for the m-phase AVR is based on the use of a vector-matrix mathematical apparatus. Using the example of a nine-phase system, a SVM algorithm has been developed, the feature of which is the transformation of the generalized voltage vector m-phase coordinate system into (m – 1)/2 voltage vectors with different angular velocities in two-phase orthogonal stationary αβ coordinate systems. At the same time, based on the developed PVM algorithm, it is possible to independently control the (m – 1)/2 voltage vectors in the corresponding αβ planes, providing a signal similar to the EMF of the generator at the input terminals of the AVR. In order to confirm the theoretical propositions, an imitation model of the space-vector modulation unit for the realization of trapezoidal signals at the terminals of a nine-phase AVR has been developed. The efficiency of the developed algorithm is confirmed by the results of simulation modelling. As a result of the evaluation of the energy parameters (operating power) of the phase of power supply system direct current, it is established that the application of the developed space-vector modulation algorithm for the active voltage rectifier in order to fully match the trapezoidal shape of the EMF and the current at the output of the m-phase generator will increase the power of the APSS by 14 % compared to a power supply system of direct current with a sinusoidal form of the EMF and the current of the generator phase. It is established that the developed measuring device can be used to establish the presence of defects like “delamination”. The influence of the depth of the defect placement on the measured parameters is shown.