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The inverter input reactor, also known as "inverter input reactor" or "inverter input reactor", needs to be installed on the power supply side of the inverter to suppress the high-order Harmonic, to solve the problem of high-order harmonic interference, improve the power factor of the frequency conversion system, and can also suppress the Dv/Dt of the power supply. The wider the application.

1. The working principle of the inverter input reactor
1. Smooth waveform
When the AC current is input into the inductance coil of the reactor through the frequency converter, the coil will generate a self-induced electromotive force, which will change with the change of the current waveform, and always prevent the increase or decrease of the original electromotive force. When the input current increases, the self-inductance electromotive force of the inverter input reactor will prevent the current from increasing; To a smooth waveform, suppress the effect of Dv/Dt of the power supply.

2. Suppress harmonics
The inductance of the inverter input reactor = the inductance of the inverter input reactor * frequency. That is to say, as the frequency of the input current increases, the inductive reactance of the inverter input reactor will also increase. For high-frequency currents, the inverter input reactor is equivalent to an open circuit state. This is why the inverter input reactor can block high-frequency current and allow low-frequency current and DC current to pass through.

2. Selection of inverter input reactor
For the selection of the input reactor of the MLAD-VR-SR inverter, the following parameters need to be clarified:
1. Power supply type: single-phase, three-phase

2. Rated current: The rated current here refers to the rated current of the motor. In reality, we often encounter such situations. Although the power of the frequency converter is large, the rated current of the motor is very small. At this time, if the type selection is based on the rated current of the inverter, it will not only increase our use cost and installation space, but also lead to unsatisfactory filtering effects. Therefore, it is more reasonable to choose according to the rated current of the motor. Economy.

3. Purpose of installation: To clarify the purpose of installation, it is mainly to select the appropriate reactance rate of the input reactor of the MLAD-VR-SR inverter. Different purposes have different requirements for the reactance rate of the input reactor of the inverter. For example, in order to suppress the high-frequency harmonics generated by the inverter during the rectification process, it is generally good to use the MLAD-VR-SR inverter input reactor with a reactance rate of 2%; but if in order to suppress the Dv/Dt of the power supply side , then, it is recommended to install the MLAD-VR-SR inverter input reactor with a reactance rate of 4%, especially in the case of large Dv/Dt. But it must be clear that the reactance rate of the input reactor of the MLAD-VR-SR inverter should generally not exceed 5%.