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killing harmonics

killing harmonics

killing harmonics

(OP)
i want to make a filter to clean my ac line, but wich harmonics are the principal to deal with? i work in audio environment and usually i have to connect very low loads (very impositive) between 38 and 110 Hz in the mains and beats of 0.7 - 0.8 millisecond, high power peaks.

i dont know, first to kill third and 5th or to make a LPF at 70 Hz -3 dB? needing some advice.

thankx.

killa

RE: killing harmonics

Suggestion: The low pass filter would not filter out subharmonics and interharmonics. The most accurate filtering would be a notch filter for the specific frequency, and in your case a bandpass filter that would pass frequencies from 38Hz to 110Hz.
See the engineering and design of filters in:
Donald G. Fink, H. Wayne Beaty "Standard Handbook for Electrical Engineers," 13th Edition, McGraw-Hill, Inc., 1993, page 2-57
Section: Filters by Harry W. Hale and Edwin C. Jones Jr.
There are software packages that design the passive filters effectively.

RE: killing harmonics

What's your budget? There are some excellent active filters which flatten all harmonics up to a few kHz, but these tend to be three-phase. I think a US company called Powersmiths was developing a single-phase unit a few years ago, but I don't know if it ever went into production.



RE: killing harmonics

Suggestion: Visit
http://www.thomasregister.com
and type Filters: Harmonic under Product or Service, which will return 40 companies to approach to

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