Control Method For Matrix Converter Research Articles

Modified Single Stage AC-AC Converter

<p>The paper describes the single stage AC-AC converter. This converter is a good alternative to quasi direct back to back converter. This single stage converter is called Matrix Converter. Matrix converter is an array of controlled semiconductor switches that connects three phase source to the three phase load. This converter provides bidirectional power flow, sinusoidal input and output waveforms and they have no dc link storage elements. Simulation model and results presented showing Venturini control method of matrix converter.</p>

A control method of matrix converter for plasma control coil power supply

Since a tokamak fusion reactor will require a fast response and precise power supply to control the coil current, we propose a matrix converter configuration, as a candidate, having a filter in a load side and smaller elements than a conventional matrix converter. Coil current control performance of the candidate converter has been evaluated by a simulation model using the code “PSCAD/EMTDC.” Simulated circuit parameters were: 30 mH for the load coil, 1 kV for the matrix converter input voltage, and ∼100 A for the output coil current. The PWM (pulse width modulation) control using triangular carrier modulation of a 10 kHz carrier frequency was adopted as the control method. The simulation results show that the settling delay time of coil current in the step variation is ∼1 ms. The transient response performance of the simulated coil current to the reference current was good. We have come to a condition that the matrix converter can be applied to the plasma control coil power supply.

Unity Power Factor Operation Control Method For Single-phase to Three-phase Matrix Converter

This paper proposes a new control method of matrix converter to obtain the unity power factor operation. Source side of the matrix converter is single-phase voltage, and the load side is three-phase ac motor. The number of switching device is six, and the converter does not require a reactor or an electrolytic capacitor. Generally, it is difficult for matrix converter to control both its input current waveform and the output voltage waveform, because the switching devices are connected to both source side and load side. In this paper, applying an algebraic transfer matrix, the control method of single-phase to three-phase matrix converter applies the indirect modulation model. The indirect modulation model treats a matrix converter as a two-stage transformation converter. The rectifier of proposed model consists only diode and small L-C filter. Hence, the switching frequency is lower than the conventional model one. The inverter of the proposed model regulates both the input current waveform and the motor speed. The inverter control scheme for IPM motor is based on direct torque control (DTC). The additional current controller improves its input current waveform. Hence, an optimum switching pattern of the matrix converter realizes quick torque response and unity power factor operation. This paper describes that the proposed method achieves the power factor 97.6% by experimental tests. The experimental results confirm the feasibility of the proposed method for matrix converter.

A direct control method for matrix converters

Until now, direct control methods have been mainly investigated and used in conjunction with voltage source converters. In this paper, the authors develop a direct current control method for matrix converters. There are two objectives for the direct current control: the desired current has to be impressed into the load, and the current, drawn from the mains, should be in phase with the voltage and should be (nearly) sinusoidal. This implies active damping of the 400 Hz resonance or the line filter. The method is implemented on a DSP and tested on a 10 kVA matrix converter.

The use of matrix converters in direct torque control of induction machines

In this paper, a new control method for matrix converters is proposed which allows, under the constraint of unity input power factor, the generation of the voltage vectors required to implement the direct torque control (DTC) of induction machines. Using this control method, it is possible to combine the advantages of matrix converters with the advantages of the DTC schemes. Some numerical simulations are carried out, showing the effectiveness of the proposed method in steady-state and transient conditions. Some experimental tests were also carried out demonstrating the practical feasibility of this control scheme.