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Introduction

·The PWM output voltage contains many high frequency harmonics (because of the fast switching) and can be a major source of EMI.

·The input rectifier draws current only at the peak of the supply waveform, so the input currents have a poor form factor ( i.e. the RMS value can be quite high - this does not mean the inverter is inefficient!).

A practical inverter needs to be designed for ease of use and installation. Large inverters are often specially designed or engineered for each application; smaller inverters are designed for general purpose use and are of standard design. Siemens Standard Drives division manufacture standard inverters for this purpose.

MICROMASTER Applications Handbook

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