The AC speed control system mainly refers to the frequency conversion speed control system of the electronic power converter to the AC motor. The frequency conversion speed control system is superior to the characteristics of DC drive, and is used as the preferred transmission scheme in many occasions. Modern frequency conversion speed regulation basically adopts 16-bit or 32-bit single-chip microcomputer as the control core, thus realizing full digital control and speed regulation. The performance is basically similar to the DC speed regulation. However, when the inverter is used, the maintenance work is more complicated than the DC. Once the fault occurs, the ordinary electricians of the enterprise are difficult to handle. Here, the common faults of the inverter are analyzed. Approach. First, the parameter setting class failure When the commonly used inverter is in use, can it meet the requirements of the transmission system? The parameter setting of the inverter is very important. If the parameter setting is incorrect, the inverter will not work normally. 1, parameter settings Commonly used inverters, generally shipped from the factory, the manufacturer has a default value for each parameter, these parameters are called factory values. In the case of these parameter values, the user can operate normally in panel operation, but the panel operation does not meet the requirements of most transmission systems. Therefore, before using the inverter correctly, the user should proceed to the inverter parameters from the following aspects: (1) Confirm the motor parameters. The inverter sets the power, current, voltage, speed and maximum frequency of the motor in the parameters. These parameters can be directly obtained from the motor nameplate. (2) The control mode adopted by the inverter, namely speed control, torque control, PID control or other means. After taking the control method, it is generally necessary to perform static or dynamic identification according to the control accuracy. (3) Set the startup mode of the inverter. Generally, the inverter is set to start from the panel at the factory. The user can select the startup mode according to the actual situation. You can use the panel, external terminal, communication mode and so on. (4) For the selection of the given signal, the frequency of the inverter can also be given in various ways. The panel is given, the external reference, the external voltage or current is given, the communication mode is given, and of course the frequency of the inverter is given. It can also be the sum of one or several of these ways. After the above parameters are correctly set, the inverter can basically work normally. If you want better control effect, you can only modify the relevant parameters according to the actual situation. 2, the parameter setting class fault handling Once the parameter setting class fault occurs, the inverter can not operate normally. Generally, the parameters can be modified according to the manual. If the above is not possible, it is best to restore all the parameters to the factory values, and then reset according to the above steps. For each company's inverter, the parameter recovery method is different. Second, overvoltage faults The overvoltage of the inverter is concentrated on the tributary voltage of the DC bus. Under normal circumstances, the inverter DC power is the average value after three-phase full-wave rectification. If calculated with a line voltage of 380V, the average DC voltage Ud=1.35U line = 513V. When the overvoltage occurs, the storage capacitor of the DC bus will be charged. When the voltage is up to 760V, the inverter overvoltage protection action. Therefore, the inverter has a normal operating voltage range. When the voltage exceeds this range, the inverter may be damaged. There are two types of common overvoltages. Concerned about surprises Label: AC motor inverter Previous: The treatment of groundwater in the design of ground source heat pump Next: Decoration and purchase of small pieces of hardware have a coup Decorative Laminates,High Pressure Laminate Panels,Laminate Wall Panels,Wood Color Wall Paneling Jiangmen Feifan Industrial Co.,Ltd , https://www.cementboard.net
AC motor inverter common faults and countermeasures