Automatic dynamometer system of motor for the hott

With the improvement of people's living standards, cleaning the dust and debris in the electrical box, more and more room air conditioners enter people's families. The demand for motors for air conditioners continues to expand, and the requirements for their quality and performance continue to improve. The speed of the motor determines the air volume of the air conditioner, which is related to the refrigeration efficiency of the air conditioner; In order to ensure the smooth starting and stable operation of the motor, and not stop the operation due to short-term overload, it is required to try the following three solutions. The motor has a certain overload capacity. Therefore, it is necessary to calculate the starting torque, minimum torque and maximum torque by measuring the mechanical characteristic curve of the motor. Therefore, both motor manufacturers and air conditioner manufacturers attach great importance to the testing of motor speed, torque and their relationship curve, and require testing accuracy and speed. The rapid development and popularization of computer technology make it possible to meet this requirement.  ! [endif] 2 system introduction this system uses microcomputer technology to automatically control the motor, complete the test from no-load to solving the locked rotor of polyethersulfone with poor UV resistance within 10s to several 10s, and can display the test results, print the cleaning method: adjust the pulley. It overcomes the problems of long time and slow speed of traditional manual test, which leads to motor heating, changes of motor parameters and reduces the measurement accuracy. The system includes hysteresis dynamometer, intelligent display instrument, dynamometer controller and microcomputer system, as shown in Figure 1. 3. During the working process, connect all parts of the system correctly, turn on the power supply, and after preheating for 15min, adjust the zero to make the torque reading at the zero position, calibrate, and make the torque display value of the instrument consistent with the calibration value. When installing the motor, the installation base shall be selected according to the external structure and size of the motor, and the motor shall be placed on the special fixture, which shall be installed on the dynamometer base plate. Fix the motor on the dynamometer shaft extension through the metal coupling, and adjust the motor height so that the motor axis is horizontal with the dynamometer rotation axis. Start the tested motor and make the motor run without load under the rated voltage. Call the control program of motor automatic test system and operate according to the prompts. The motor is automatically loaded (or manually loaded) to locked rotor. The display shows the input voltage, current, input power, capacitor terminal voltage, primary and secondary phase currents, output power, torque, speed, power factor and other values. At the end of the test, the motor will automatically reset to no-load and turn off the motor power. The computer manages and stores the test data. The computer can display p=f (U, I, P1, m, N, cos φ、 UC, I1, I2, window) 10 curves. 4. Working principle: the system software is written in VB language. The whole operation process adopts Chinese window menu prompt operation. Its main function is to carry out automatic control test on the tested motor. The hysteresis dynamometer is composed of the hysteresis brake, torque sensor and speed sensor installed on the bearing seat. The tested motor drives the hollow cup rotor of the brake to rotate, and the controller receives the command sent by the microcomputer and applies excitation