MICROPROCESSOR OR COMPUTER BASED
CONTROL OF SRM DRIVE
industrial places there is high demands on control accuracies, flexibility,
ease of operation, repeatability of parameters for many drive applications.
Nowadays switched reluctance motors are increasingly used in industries. To
meet the above requirements, uses of microprocessor have become important.
shows the block diagram of microprocessor based control of SRM drive. This
control system consists of power semiconductor switching circuit, SRM with
rotor position sensor and microprocessor system. In this system microprocessor
acts as a controller for the switched reluctance motor and generate control
pulses to the power semiconductor switching circuits.
DC supply is fed to the power semiconductor switching circuits. Different types
of power semiconductor switching circuits are used for different application.
Normally the circuits are inverter circuit configuration.
semiconductor devices are turned on and off by controller circuit. Here the
controller circuit is microprocessor or computer based control system.
SRM drive shown in fig. 3.14, the rotor position sensor gives the information
about the rotor with respect to the reference axis to the microprocessor or
computer control. The controller also receives the status of current, flow
through the phase winding and reference signal.
microprocessor or computer compares the signals obtained from the RPS and
reference and generate square pulses to the power semiconductor devices. This
signal is fed to the inverter circuit. The phase winding of the SRM is
energized depending upon the turning on and off of the power semiconductor
microprocessor or computer controller can perform the following functions.
the feedback loops.
b) PWM or
square wave signal generation to inverters.
and adaptive control.
monitoring and warning.
and fault overriding control.
superiority of microprocessor or computer control over the conventional
hardware based control can be easily recognized for complex drive control
system. The simplification of hardware saves control electronics cost and
improves the system reliability. The digital control has inherently improves
the noise immunity which is particularly important because of large power
switching transients in the converters.