FAQ# DRV-64VLZY Published: 03/14/2006
Question:Power Line Harmonics and Installation Considerations for AC and DC Drives
Answer:

Yaskawa General-Purpose Inverter Technical Information

    ClassificationPrecautions on ApplicationModelGNDocument No.YEA-P-01-GN-01
    TitlePower Line Harmonics Considerations for DC Drives and AC Drives
    Page2

    DC Drives



    DC Drives and SCR Power Conversion

    SCR power conversion and Diode power conversion sections effect voltage and current harmonics differently. Also, system impedance has a large impact on voltage and current harmonics present in the power system.

    SCR Front End Of A DC Drive

    DC drives for the most part, utilize Phase Controlled Converters, referred to as Silicon Controlled Rectifiers (SCRs), in the input rectifier stage.




    Basic Schematic for DC Drive (SCR Diode Bridge)

    In this application, the line current will be relatively square in shape, which is generally the case
    for DC drives that usually have a DC link choke.

    Reactance located on the AC side of the SCR bridge will have a relatively small effect on total current
    distortion but, may drop the total voltage distortion considerably. In this situation, the total voltage
    distortion levels will be relatively high and may effect low voltage equipment.


Product Information:

Product Group:Inverters/Drives
Product:F7 Drive
Applications:
Category:Harmonics; Isolation Transformers; Power Quality; Reactors

Other Information:

Link to related files:Power Line Harmonics Considerations

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Please read and understand the product instruction manual before installing, servicing or operating Yaskawa products. FAQ content and illustrations are provided as technical advice to augment the information in manual, not superceed it. It is not possible to give detailed instructions for all types of installation or support activities. The information described in the FAQs are subject to change without notice to improve the product or FAQ. Yaskawa assumes no responsibility for errors or omissions or damages resulting from the use of the information contained in any FAQ. All warnings, cautions and product instruction for product use must be followed. Installation, operation and maintenance should be carried out by qualified personnel. Failure to observe these and other precautions highlighted in the product manuals will expose the user to high voltages resulting in, serious injury or death. Qualified personnel are defined as individuals who are familiar with the installation, starting, operation and maintenance of Yaskawa products of the type described and have proper qualifications to perform the work.