The three-phase alternators driven by the wind provide voltages (50 to 400v) and currents to frequency variable from 10 to 100Hz

(it depends on wind speed).

Can I use ADE7758 in this field of frequencies? If yes, what is the percentage error on currents, voltages e powers ?

What kind of transducers (voltage / current) do you recommend? TA generally have a band that starts at around 35Hz.

I thought to an Aron configuration for measurement of active and reactive powers. What do you think ?

Is it possible to measure the frequency with ADE7758 ?

Are there another best ADE ICs for this kind of applications? Thanks for your help. Bye

Hi PP62

In ADE7758, the bandwidth of measurement is very high (14 KHz) for current RMS and active energy measurements. But for voltage RMS ( it is a mean absolute value) , the 3 dB bandwidth is only 260 Hz. So, even though it would be fine at the fundamental, if there are any harmonics beyond 260 Hz ( even at 260 Hz, there is 3 dB attenuation), the results will not be accurate. As apparent energy is computed from VRMS too, that will also be affected in that case. The reactive energy is computed by phase shifting the current fundamental signal by 90 degrees and this will not be accurate for the entire range of frequencies that you are interested in; it is intended to operate well at 50 Hz/60 Hz. There is a frequency register but that too is accurate only from 40-70 Hz. The period, however, will work fine for all frequencies, and you can calculate frequency from that externally.

I would recommend you to consider ADE78xx products for your application. The table in the first page will show the feature differences among the four chips in this family. All the RMS and energy measurements have a 2 KHz 3dB bandwidth. So, this must be a good fit for your application. Equation 7 (page 36) in the datasheet will show you how to convert the PERIOD register reading into line frequency. For accuracy of these measurements, kindly have a look at the specifications table in the datasheet. What is the range of current signal amplitudes in your application?

Do you wish to do any harmonic analysis in particular? Like calculating THD, harmonic powers, etc.?

For current sensors, look for Current transformers or Rogowski coils with bandwidth high enough to let through signals in the desired frequency range, unattenuated. For voltage channel, a simple resistor divider will work well.

How will your 3-phase system configuration look like? Is it a 3-phase 4-wire wye configuration?

I would expect this App note to help you with answers to many fundamental questions regarding ADE chips. Let me know if there are any further questions.

Regards

hmani