How To Set The Parameters Of Inverter

To know how to set the parameters of the converter, first of all, we should understand what the converter is and what work it does. Frequency converter is a kind of power supply device used to adjust the speed of asynchronous motor. According to the formula of speed n=60f/p(1-s), frequency converter is essentially a voltage source with adjustable output frequency. It changes the speed of motor by changing the frequency of power supply. At the same time, in order to avoid the overheating caused by flux saturation, it also changes the voltage, that is to say, to keep the V/F ratio constant, so frequency conversion is necessary. The parameter setting of the device is based on this core.

Motor-related parameters

Frequency converter is for motor service. Frequency converter and motor should be used together, that is, the rated voltage and power of both should be very close. In the process of motor operation, to avoid excessive current and heat burnout, it is necessary to set some relevant protection parameters.

Rated voltage: Although the motor voltage controlled by the frequency converter is basically 380 volts in three phases in China, it is not excluded that some imported equipment is special. If you change the frequency converter, you should pay attention to it. For example, when Japan comes in, it may be 220 volts in three phases.

Rated current: There is this parameter on the nameplate of the motor, and the corresponding input is good.

Overload protection: This is actually a parameter to control the instantaneous maximum power. The common parameter is 110%, which can be adjusted to 150%, depending on the actual situation.

Limit Frequency: China generally uses 50HZ, but in some cases it needs to be overused, such as some machine tool spindles, which may be 75HZ earlier. It should be selected according to the working conditions, but it can not be too high, otherwise the motor bearings can not bear.

Start Frequency: Frequency converter often can not output very low frequency to drive the motor, usually starting time is often higher than 0.5HZ.

Power supply parameters

Torque lifting: There are automatic and manual mode choices. If the effect of automatic mode is not good, you can choose manual mode. The essence is to set the V/F ratio.

Torque enhancement: Considering the lack of motor torque at low speed, some occasions need to increase the voltage value, which is the so-called torque enhancement, but it can not be increased too much, otherwise it may be unstable. Acceleration and deceleration time: In theory, the shorter the acceleration and deceleration time of frequency converter, the greater the fluctuation of motor current and voltage. But in many cases, the shorter the acceleration and deceleration time of motor is needed, so this need to be set according to the load situation.

Control mode: general general load using V/F mode is good, if it is vector control, you can choose inductance-free vector or inductance vector, depending on the control accuracy to set, if you choose vector control, also need to do parameter self-adaptive adjustment.

Man-machine control parameters

Inverter should be controlled and operated by people, such as starting it, stopping it, how fast it runs, slowing it down and so on, all need to be set up

Start Source: This includes start and stop functions. If I/O control is adopted, the corresponding I/O port can be selected. Most converters are fixed to a certain I/O, and they can also be set up panels, and some are even controlled by means of communication.

Frequency Source: It's the same as the starter source, but the frequency source is usually analog, in the form of voltage and current. In some cases, multi-stage speed control is achieved by multiple I/O, and also by means of communication