Chaotification and fuzzy PI control of three-phase induction machine using synchronization approach

In this manuscript, a three-phase asynchronous machine is forced to behave chaotically. The rotor speed becomes chaotic and thereafter is forced to follow a constant speed using a fuzzy controller. The approach is useful to attain an optimum trajectory planning. This will be achieved in two stages of; chaotification and control. Primarily outputs of the three-phase induction motor in terms of currents, voltages and speed become chaotic. The chaotification is achieved in a synchronization framework, considering a fifth-order nonlinear dynamics. In this approach, Lorenz chaotic system (as master) is applied as an input to the system when (speed of) the motor as a slave will be synchronized. The achieved synchronization error enters a fuzzy PI controller where an inverter provides required correspondent three phase voltages. According to this strategy, the voltage source inverter works as an actuator to provide a sinusoidal three-phase voltage with required frequency in a V/f constant ratio mechanism. In the second step, the chaos is stabilized at a constant value when the Lorenz master system is arbitrarily controlled. In this regard, the chaos in the motor speed is controlled and stabilized in response to a constant command. Two simulations of HWIL (Hardware in the Loop) approach and software implementation are carried out. Simulation results show that the proposed scheme can effectively make the motor outputs chaotic where another cascade control tunes the speed. Practical HWIL realization ultimately confirms the achievement.