| Switched reluctance drive (SRD) combines the electrical motor theories with the modern power electronics technique and the advanced microprocessor control technique, which has low-cost strong structure, good fault-tolerant capability. It has many advantages of adjustable-speed drive, so it attracts more and more attention and shows competition in commercial applications.In this paper the switched reluctance control system is designed using TMS320LF2407A DSP as its core processor and a 750W 3-phase 12/8 poles switched reluctance motor as its prototype motor. The hardware and software of control system succeed in application in the high power SRD control with good results.Control strategy has been improved in this paper. Firstly, the paper establishes mathematical model of switched reluctance motor, sets up three phase-commutation logics through analysis of inductance ,current curve and mathematical model, makes the motor stably operate in different speed conditions. Secondly, to solve the problem of higher torque ripple at lower speed, it proposes a suitable set of phase-commutation logics and a control strategy which changes the point phase-commutation to the area phase-commutation, at the same time, it adopts hysteretic current chopped control to inhibit over-current and improve the motor operation performance during low speed. Thirdly, it mounts soft-start potentiometer on the hardware circuit to accommodate start time, designs two kinds of soft-start control strategy though the assembly of hardware and software, improves the motor's start performance. Finally, according to the structure of 12/8 poles SRM, it proposes the self-lock strategy which keep one phase continuous on to gain braking and position torque, at the same time , use the current loop to realize constant-current control, accommodates braking torque through the braking control potentiometer which can limit the current, make motor brake stably, and make the motor's braking time accommodable .
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