Applications and Functions of Microprocessors in Electric Drives:

With the remarkable progress in the area of microelectronics, reliable and powerful microprocessors have come to be more widely used in the control of electrical drives. A few of the Applications and Functions of Microprocessors in Electric Drives can be listed as follows:

1. Static Ward Leonard control of dc motor using dual converters
2. Four quadrant control of dc motor using multiphase choppers
3. Control of PWM inverter for ac motors
4. Four quadrant operation of CSI fed ac drives
5. Four quadrant operation of cycloconverter fed ac drives
6. Static motor starters

In variable speed drives using thyristor power converters and electric motors (ac or dc) the functions of a microprocessor are the following:

1. Generating and providing firing pulses to the converters
2. Generation of necessary waveforms to feed the motors
3. Nonlinear function generation. Estimation of feedback signals. Imple­mentation of software supported controllers in the feedback control, such as current controllers, speed controllers, etc. The limiters are also implemented to limit the control variables to safe values
4. Processing the measured signals, such as voltage, current and speed
5. Storing and processing the information of controlled quantities
6. Estimation of feedback signals and computation of reference quantities which cannot be directly measured, such as torque and flux
7. Adaptive control and optimisation
8. General sequencing control
9. Monitoring and warnings
10. Diagnostics and tests