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GD350A series high-performance multifunction VFD
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3 Product overview
3.1 What this chapter contains
This chapter mainly introduces the operation principles, product features, layouts, nameplates and
model designation rules.
3.2 Basic principle
The VFD is used to control asynchronous AC induction motors and permanent-magnet synchronous
motors. The figure below shows the main circuit diagram of the VFD. The rectifier converts 3PH AC
voltage into DC voltage, and the capacitor bank of intermediate circuit stabilizes the DC voltage. The
VFD converts DC voltage into the AC voltage used by AC motor. When the circuit voltage exceeds the
maximum limit value, external braking resistor will be connected to intermediate DC circuit to consume
the feedback energy.