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This study proposes an induction motor drive system based on the LC filter integrated quasi‐Z source indirect matrix converter (QZS‐IMC). The proposed drive system shows the following features: (i) variable voltage control of inductor motor is achieved by the rectifier stage and variable frequency control is achieved by the inverter stage; (ii) automatic low voltage ride through ability enhances capability of the proposed drive against grid voltage sag; (iii) wide voltage gain range ensures the drive system with high performance in wide speed range; (iv) there is no additional input filter. The voltage control implementation in the rectifier stage is proposed to benefit low voltage stress and low converter loss. The control method combines motor vector control, minimum shoot‐through duty cycle and maximum modulation indexes. As a result, the input power supply voltage and dc‐link voltage are maximally utilised and the power loss is reduced. Simulation and experimental results verify the proposed QZS‐IMC motor drive system. [ABSTRACT FROM AUTHOR]

Summary: The existing model of LC filter integrated quasi‐Z source indirect matrix converter (QZS‐IMC) was derived using the DC circuit modeling method, which is mainly effective in DC circuit. As an ac circuit, the existing voltage boost ratio model of LC filter integrated QZS‐IMC exhibits a big error from the real boost ratio. Moreover, current amplitude and phase angle of QZS network were not considered in the existing model. This paper proposes a new comprehensive model of LC filter integrated QZS‐IMC taking into account the circuit's ac characteristics. The new model shows that voltage boost ratio is strongly related to QZS network inductance, capacitance, and frequency of input power supply. It can be concluded from the new model that the boost ratio is higher than 1/(1 − 2D), which is the boost ratio of existing model. Moreover, the new model shows that power factor affects voltage gain of QZS‐IMC system. The new model is compared with the existing model, circuit simulation, and experimental test. The results verify the new model and analysis. [ABSTRACT FROM AUTHOR]

The existing single‐phase, quasi‐Z‐source inverter (qZSI), photovoltaic (PV) power system with integrated battery energy storage (BES), abbreviated as BES‐qZSI‐PV power system, has several well‐known advantages, but cannot operate at night because there is no PV power input. In this study, a solution to overcome this issue is proposed. First, the power circuit of the conventional BES‐qZSI‐PV topology is modified to allow its operation at both day and night. Then, the system model for the night‐operation mode is built and a qZS network parameters' design method to limit the double‐line frequency harmonic at the dc side is developed. A control strategy to ensure the high‐performance operation of the system at all times, is proposed. Based on an experimental platform of single‐phase BES‐qZSI‐PV power system, three groups of experimental tests with different qZS network parameters and battery voltages are carried out to verify the model and parameters design method by means of comparing the experimental, circuit‐based simulated, and model‐based calculated results. The proposed BES‐qZSI‐PV system performance is experimentally evaluated in steady‐state operation and day‐to‐night transit operation, as well as by the power efficiency curves in day‐ and night‐modes. [ABSTRACT FROM AUTHOR]