The frequency of the inverter can't be adjusted. If there is no damage on the hardware, the maximum torque output of the inverter is less than the load to increase the torque. It is said that the inverter can be loaded with load. We can analyze and search from the following 6 points. method:
1, speed up the time is too short
In theory, the longer the speed is, the stronger the load with the load will be. The setting speed is too short. Some inverters will show over current or overload and overheat alarms, but some will not show up, just stuck in a certain The frequency band does not go up.
2, V / F ratio is too large
This some inverters are also called torque boost. This parameter setting is too large, and sometimes it will not be able to start normally, which will reduce the problem.
3, vector control parameters do not match
In the vector control mode, the inverter manufacturer needs to measure the internal resistance and inductance of the motor carefully, and cooperate with the vector parameter requirements of the inverter. After a period of operation, the motor parameters are overheated to form an offset, and the current will be too large. The motor cannot be started normally, the frequency may also be stuck at a certain point, and the parameters can be re-optimized to deal with the problem.
4, the highest frequency and maximum frequency setting is too low
Generally, these two parameters are set to the maximum value, but the electrician who does not sweep some thick branches and leaves has changed these two parameters, so it will not be able to increase the frequency.
5, some special occasions parameter needs pairing
In some occasions, the lowest frequency cannot be set too low. For example, in the constant pressure water supply system, after the lowest frequency is set to 0 Hz, when the pump pressure is low, the inverter starts to speed up when the frequency of the inverter is exceeded, and the pressure is not added. How to increase the frequency is less than 50Hz, only about 38Hz, repeat setting and conditioning the PID, the frequency will not go. As long as the lowest frequency of the inverter is set to about 15-20HZ, the speed of the inverter can be satisfied, and the pump can be pressed to a certain pressure direction. Although the pressure is satisfactory for the constant pressure requirement, when the water is not used, the inverter cannot be completely stopped, and the speed of the lowest frequency is maintained at all times.
This is because: in the constant pressure water supply system, the lowest frequency of the inverter can not be set to 0HZ, generally at least about 20HZ, which is determined by the flow and head of the pump.
The method of treatment is to set the sleep frequency. When the frequency of the pump does not use water (for example, 28HZ) for several minutes, the pump sleeps. When the pressure drops to 0.2-0.4MP lower than the set pressure, the pump starts. Another method is to set up punctual water supply, and punctual water supply in several time periods. Generally, the constant pressure water supply controller has the functions mentioned above.
6, hardware problems
After the transformer's transformer (Hall) presents a problem, it can't measure the correct current normally, or it may have a similar situation. In addition, a certain measuring component on the main board will be aging, and this situation will also occur. These are repairing the inverter. I often come across it.