Control system of wind generator based on switched reluctance motor

Abstract

The work is devoted to the development of a control system for a wind generator with the use of a switched
reluctance motor. The search for new structures for the construction of the power unit and control system of electromechanical
systems of wind power complexes is an urgent task of today. The most common construction options for such systems include doublefed induction motors and permanent magnet synchronous generators. In the first case there is no possibility of full control of the flow
of power transmitted to the network, and in the second case the main disadvantage is the high cost of such an electric machine,
which is explained by the use of rare earth materials in its design. The use of a switched reluctance motor as a generator has
significant differences compared to similar use of electric machines based on torque generation due to the Lorentz force. A
mathematical model of the electromechanical system of a wind generator with a switched reluctance motor in the Matlab / Simulink
environment was developed. It was shown by mathematical modeling that when changing the sign of load torque, the machine does
not go into braking mode independently, as is the case with other electric machines. This creates considerable difficulties in the
operation of such a system, since the transition to brake mode requires a change in control effects on the switched reluctance motor.
Features of functioning of the switched reluctance motor in the mode of regenerative braking have been stated. The limits of change
of control angles which allow to receive the maximum amount of the generated electric energy and reduction of pulsations of brake
torque of the machine have been defined. The structure of the control system of a switched reluctance motor has been developed,
which involves the use of a modified speed controller, which divides its output signal into a sign function, which is subsequently used
to select the converter control angles, as well as the absolute value used in the operation of the modulation algorithm of the required
current magnitude .