Simple structure; The motor has simple structure, low cost and can be used for high-speed operation. The SRM is simpler than a squirrel-cage induction motor. The rotor has very high mechanical strength and can be used for ultra-high speed operation (such as tens of thousands of revolutions per minute). In terms of stator, it has only a few concentrated windings, so it is simple to manufacture and simple insulation structure.
Reliable circuit; The power circuit is simple and reliable. Because the direction of the motor torque has nothing to do with the direction of the winding current, that is, only a single phase winding current is needed, so the power circuit can achieve a power switch per phase. In contrast, the winding of an asynchronous motor needs to flow bidirectional current, and the PWM converter power circuit that supplies power to it needs two power devices per phase. Therefore, the switched reluctance motor speed regulation system requires fewer power components than the PWM inverter power circuit, and the circuit structure is simple. In addition, two power switch tubes in each bridge arm of the PWM converter power circuit are directly across the DC power supply side, which is easy to burn the power device through short circuit. Each power switch device in the speed control system of the switched reluctance motor is directly connected with the motor winding in series, which fundamentally avoids the phenomenon of direct short circuit. Therefore, the protection circuit of the power circuit in the speed-adjusting system of the switched reluctance speed-adjusting motor can be simplified, that is, the cost is reduced and the reliability is higher.
High system reliability; High system reliability. From the electromagnetic structure of the motor, each winding and magnetic circuit are independent of each other, and each produces electromagnetic torque within a certain axis Angle. Unlike in general motors, a rotating magnetic field must be generated under the joint action of each phase winding and magnetic circuit in order for the motor to operate normally. From the point of view of the control structure, each phase circuit supplies power to a phase winding, and generally works independently of each other.
Starting advantage; Large starting torque, low starting current. The main feature of this system is that the controller outputs less current and the motor gets larger starting torque. The data of typical products are: when the starting current is 15% of the rated current, the starting torque is 100% of the rated torque; When the starting current is 30% of the rated current, the starting torque can reach 250% of the rated torque. Compared with the starting characteristics of other speed regulation systems, such as DC motor is 100% current, squirrel cage induction motor is 300% current, and 100% torque is obtained. The advantages of small starting current and large torque can also be extended to the low-speed operation section, so the system is very suitable for those machines that need heavy load starting and low-speed and heavy-duty operation for a long time.
Frequent starts and stops; Suitable for frequent start-stop and forward and reverse switching operation. The system has the characteristics of high starting torque and low starting current, so that the current impact in the starting process is small, and the motor heating is smaller than that in continuous rated operation. Suitable for frequent start-stop and forward and reverse switching operation.
Good performance; Good speed control performance. There are at least four main operating parameters and common methods for controlling switched reluctance motors: phase conduction Angle, correlation break Angle, phase current amplitude, and phase winding voltage, which are flexible and convenient. According to the operation requirements of the motor and the situation of the motor, different control methods and parameter values can be taken to make it run in the best state (such as maximum output, maximum efficiency, etc.), and can also make it achieve a variety of specific curves of different functions. If the motor has exactly the same four-quadrant operation capacity, and has the highest starting torque and the load capacity curve of the series motor. Can be used for speed closed-loop control, can be very convenient to form no static difference speed regulation system.