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What is the reason why the frequency of the inverter cannot be adjusted?

In the actual industrial production, the frequency of the inverter cannot be adjusted. If the frequency of the inverter cannot be adjusted, it mainly depends on two situations. Generally, if there is no damage on the hardware, it is because the maximum torque output by the inverter is smaller than the load lifting torque, which simply means that the inverter does not have a load capacity.
What is the reason why the frequency of the inverter cannot be adjusted?
1.The acceleration time is too short
Theoretically, the longer the acceleration time, the stronger the ability to increase the load. If the acceleration time is set too short, some inverters will display overcurrent or overload and overheat alarms, but some will not be displayed. Can't go up in this 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. A proper reduction will solve the problem.
3.Vector control parameters do not match
In the vector control mode, the internal resistance, inductance and other parameters of the motor need to be precisely measured, and the vector parameters of the inverter need to be coordinated. After running for a period of time, the motor parameters will overheat and cause deviations. At this time, the current will be too large and cannot be normal Start the motor, the frequency may also be stuck at a certain point, re-optimizing the parameters can solve the problem.
4.The maximum frequency and maximum frequency are set too low
Generally, these two parameters are set to the maximum value, but it is not ruled out that some careless electricians have changed these two parameters, so it will also make it impossible to increase the frequency.
5, some special occasions parameters need to match
In some occasions, the minimum frequency cannot be set too low. For example, in a constant pressure water supply system, after the minimum frequency is set to 0Hz, when the pump pressure is low, the inverter starts to accelerate when the inverter's starting frequency is exceeded, and the pressure is not always added. How to add the frequency to less than 50Hz, only about 38Hz, repeatedly set and adjust the PID, always the frequency does not go up. Only when the minimum frequency of the inverter is set to about 15-20HZ, the acceleration of the inverter can be satisfied, and the pump can be constant pressure to a certain pressure position. Although the pressure meets the requirements of constant pressure, when the water is not used, the inverter cannot be completely stopped and the speed of the lowest frequency is always maintained. This is because: In a constant pressure water supply system, the minimum frequency of the inverter cannot be set to 0HZ, generally at least about 20HZ, which is determined by the flow and head of the pump.
At this time, it can be solved by setting the sleep frequency. When the frequency (for example, 28HZ) when the water pump is not using water for several minutes, the water pump sleeps. When the pressure drops to 0.2-0.4MP lower than the set pressure, the water pump starts. Another method is to set a regular water supply, which is provided in several time periods. Generally, the constant pressure water supply controller has the functions mentioned above.
6.Hardware issues
After the transformer (Hall) of the inverter has a problem, the correct current cannot be measured normally, and a similar situation may occur. In addition, this phenomenon also occurs when a measuring component on the motherboard is aging. I often come across it.