Vector Control technique of a Squirrel Cage Induction Motor

The performances of an AC induction motor are strongly dependent on its control which is why the use of DSP controllers will enable enhanced real time algorithms in addition to sensorless control.

A powerful processor such as DSP (ADMC401) controller does the following:

• Favours system cost reduction by an efficient control in all speed range implying right dimensioning of power device circuits
• Performs high level algorithms due to reduced torque ripple, resulting in lower vibration and longer life time
• Enables a reduction of harmonics using enhanced algorithms, to meet easier requirements and to reduce filters cost
• Removes speed or position sensors by the implementation of sensorless algorithms
• Decreases the number of look-up tables which reduces the amount of memory required
• Real-time generation of smooth near-optimal reference profiles and move trajectories, resulting in better-performing
• Controls power switching inverters and generates high-resolution PWM outputs · provides single chip control system

In Vector Control, Field Orientated Control and the Feedback Linearisation control techniques, the dynamic behaviour of the induction motor is very similar to that of a separately excited DC motor

Matlab model

The Motor control system

The hardware of the Motor control system is composed of ADMC401 DSP Board, Power Inverter, Position Sensor, Current Sensors and Speed Position Controller. The DSP board is programmed by a Host Computer. The DSP board outputs its command control to the Inverter, which feeds the Induction Motor. The position and current sensors takes measurements from the motor and supplies the DSP Board, the speed controller provides the DSP with the desired speed required from the motor.