Product Overview; What This Chapter Contains; Basic Principle - Kruger Ecowatt K320 Series Operation Manual

Ecowatt Drive K320 series
®

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.
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Figure 3-1 Main circuit diagram for 018P and lower models
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3 Product overview

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Figure 3-2 Main circuit diagram for 022P–045P
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Product overview
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