What does it mean by carrier frequency in drives ? Why to lower carrier frequency ?

What does it mean by carrier frequency in drives ? Why to lower carrier frequency ?

YASKAWA AC Drive H1000

Super Heavy Duty, High Performance Drive

Technical Manual

Type: CIMR-HB .........
Models: 200 V Class: 0.4 to 110 kW
400 V Class: 0.4 to 560 kW

MANUAL NO. SIEP C710616 37B


The images are attached so have a look at it ....

https://obrazki.elektroda.pl/74_1336608350.jpg
https://obrazki.elektroda.pl/75_1336608350.jpg
https://obrazki.elektroda.pl/18_1336608350.jpg
https://obrazki.elektroda.pl/32_1336608350.jpg
https://obrazki.elektroda.pl/55_1336608350.jpg
https://obrazki.elektroda.pl/72_1336608455.jpg

What's the difference between "SHD" (Super Heavy Duty) & "HD" (Heavy Duty) ?
And what's the impact of lowering or increasing the carrier frequency on SHD & HD ?

thanks

The carrier frequency is the pulse repetition frequency. If its too low you can hear the drive/motor whistling, if it too high there could be additional losses and radiation. From your second .pdf, super heavy duty is when the motor is stopped and started often.
Frank

yes it stopped & started often , so i should consider SHD ?

Yes, there could be a down side. I would guess that the acceleration/de-accelaration times will be slower to preserve the braking resistor's life.
Frank

i think they're 10 sec each

what's the impact on lowering & increasing the carrier frequency of the drive ?

At what level can we increase & at what level can we decrease the carrier frequency of the drive ?

It is entirely up to you and the application you are using this drive in.
Frank

would you explain & give examples of any of the application ?

The output of the ac drive is pwm sinewave. Carrier frequency is the chopping rate of that pwm signal. The high carrier frequency will cause more heat loss in igbt module but less annoying sound from the motor. Again low carrier frequency will cause less heat loss in igbt module but more annoying sound from the motor. Try to set the carrier frequency as low as possible unless the sound of the motor is annoying.

The waveform of yours consists of 2 frequencys, that is, a carrier frequency and a signal frequency, and the signal frequency usually consists of a multiple-frequency waveform, look at AM Radio Signallings. If you want to lower down such a frequency, the best way is lower down it when you have not mix the 2 signals together. And what's more, a Doppler Effect could change such a wave frequency: As the vilocity from the receiver and boardcastor is vv(the One vertical to the line of reciever and boardcastor) and vh(the One horizotal to the line of receiver and boardcastor). And there is a formula on such cases --
Frequency(switched) = {(1 + vh/c) + [1 + (vv/c)^2]^(1/2) - 1}*Frequency(original).
Note:
If the vv leaves the boardcastor, vv is positive and if vv reaches the boardcastor, vv is negative!!