Alternating current frequency conversion high-speed asynchronous motor

Abstract

The invention discloses an alternating current frequency conversion high-speed asynchronous motor, which is provided with a rotor, a stator and a frequency converter, wherein the frequency converter has the rated frequency of 200Hz; the ratio of the internal diameter of the stator of the motor to the core length is 0.4-0.8; stator and rotor laminations are made of cold-rolled silicon steel plates with good magnetoconductivity; the flux density of the motor is controlled in a certain range, wherein the flux density of stator teeth is 0.9 to 1.4T, the flux density of a stator yoke is 0.8 to 1.1T, the flux density of rotor teeth is 0.9 to 1.35T, the flux density of a rotor yoke is 0.6 to 0.85T, and the flux density of air gaps is 0.45 to 0.6T; the current density of a stator winding is 3.0 to 5.0A / mm<2>, the current density of a rotor bar is 1.1 to 3.0A / mm<2>, and the linear load is 180 to 250A / mm<2>; the insulation is class H insulation, the first turn is sleeved with an insulation tube, and an IGBT insulation system is executed; the stator and rotor windings are vacuum-pressure secondary impregnated windings; the rotor is provided with an intermittent balancing ring; a gap of a matching surface of an axis rotating piece and an axis fixing piece is 80 to 100 percent of the maximum gap of the normal motor; and an air gap of the stator is 25 to 40 percent larger than that of the normal motor. The alternating current frequency conversion high-speed asynchronous motor maintains the characteristics of the traditional motor, and has the advantages of high rotating speed, stable and reliable operation, small vibration and noise, and lower cost.

Description

technical field [0001] The invention belongs to the technical field of motors, and in particular relates to an AC variable-frequency high-speed asynchronous motor. Background technique [0002] At present, the maximum synchronous speed of AC variable frequency speed regulation asynchronous motor is 6000r / min, the rated frequency is 50Hz, and the constant torque is below 50Hz, and the constant power load characteristic is above 50Hz. Depend on (n: motor synchronous speed f: motor rated frequency P: number of motor pole pairs) It can be seen that by increasing the rated frequency of the inverter, the speed of the motor can be increased, but when the rated frequency exceeds 100HZ, the frequency conversion motor with a rated point of 50HZ Generally speaking, if the frequency of the motor continues to increase, the torque of the motor will be very low, resulting in the inability to drive the load to operate normally. In recent years, more and more high-speed supporting equipmen...

AI Technical Summary

Problems solved by technology

Depend on (n: motor synchronous speed f: motor rated frequency P: number of motor pole pairs) It can be seen that by increasing the rated frequency of the inverter, the speed of the motor can be increased, but when the rated frequency exceeds 100HZ, the frequency conversion motor with a rated point of 50HZ Generally speaking, if the frequency of the motor continues to increase, the torque of the motor will be very low, resulting in the failure to drive the load to run normally. In recent years, more and more high-speed supporting equipment devices need to be equipped with high-speed motors. Therefore, for this high-speed The motor needs a special design, which can increase the motor from the traditional maximum synchronous speed of 3000r / min to 12000r / min, and meet the characteristics of a normal motor

During the operation of this kind of high-speed motor, the following problems may occur: 1. The speed of the motor is very high, and the moment of inertia is relatively large; 2. When the frequency is high, the voltage output by the inverter contains a higher frequency than the carrier frequency Subharmonics will increase the loss and temperature rise of the motor, and the coil and insulation need to withstand high impact voltage; 3. The balance accuracy of the rotor and safety issues at high speed; 4. The deflection of the shaft will increase by 15% Left and right, affecting the reliable operation of the motor; 5. Maintain good operating performance within a wide frequency conversion range, and use frequency converters for power supply, which will damage the motor bearings

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