1. Acceleration time is too short
In theory, the longer the acceleration time, the stronger the load lifting capacity will be. If the acceleration time is set too short, some air compressor inverters will display overcurrent or overload overheating errors, but some will not be displayed, but just stuck in a certain frequency band.
2. V/F ratio is too large
Some inverters are also called torque boost. If this parameter is set too large, sometimes it will not start normally. Appropriate reduction will solve the problem.
3. Vector control parameters do not match
In vector control mode, the internal resistance, inductance and other parameters of the motor need to be accurately measured, and the vector parameters of the inverter need to be well matched. After running for a period of time, the motor parameters will be overheated and offset, which will cause excessive current and fail to start the motor normally. The frequency may also be stuck at a certain point. Re-optimizing the parameters can solve the problem.
4. High frequency and high frequency are set too low
Generally, these two parameters are set to larger values, but it is not ruled out that some careless electricians have changed these two parameters, so it will also cause the frequency to be unable to increase.
5. Parameters in some special occasions need to be paired
In some occasions, the low frequency cannot be set too low. For example, in the constant pressure water supply system, after the low frequency is set to 0Hz, when the water pump pressure is low, the inverter starts to accelerate when it exceeds the starting frequency of the inverter, and the pressure can never be increased. The frequency of the air compressor inverter can never be increased to 50Hz, only about 38Hz. Repeatedly set and adjust PID, the frequency can never be increased. Only by setting the low frequency of the inverter to about 15-20HZ can the acceleration of the inverter be met, and the water pump can be kept at a constant pressure position. Although the pressure meets the constant pressure requirements, when no water is used, the inverter cannot be completely stopped and always maintains a low frequency speed.
This is because: in the constant pressure water supply system, the low frequency of the inverter cannot be set to 0HZ, generally around 20HZ, which is determined by the flow rate and head of the water pump.
The solution is to set the sleep frequency. When the frequency (for example, 28HZ) when the pump does not use water runs for several minutes, the pump will sleep. When the pressure drops to 0.2-0.4MP lower than the set pressure, the pump will start. Another method is to set the timed water supply, which is divided into several time periods. Generally, the constant pressure water supply controller has the above-mentioned function.
6. Hardware problem
When the transformer of the inverter has a problem, it cannot measure the correct current normally. Similar situations may also occur. In addition, a certain measuring element on the mainboard is aging, which may also happen. These are often encountered when repairing the inverter.