There are some companies in my country(India) which try to sell inverters for home marketing in the name of DSP Sinewave Inverter and claim are superior to normal sinewave inverters.

I am trying to buy one but confused with this term.

  • What is DSP used in inverter for?

  • Does it have a edge over normal sinewave inverter or just a marketing hype?

  • 3
    \$\begingroup\$ Probably marketing hype - they most likely are constructing a better looking sine wave with integer frequency multiples of square waves. \$\endgroup\$ – Andy aka Apr 23 '14 at 9:15
  • \$\begingroup\$ @Andyaka But that sounds like it could have an actual useful effect to me? \$\endgroup\$ – Volker Siegel Apr 23 '14 at 9:35
  • 4
    \$\begingroup\$ Having a Sine-Wave inverter can be considerably better then a modified square wave inverter (which is likely just about any inverter that doesn't say "sine-wave" on it's packaging). However, the fact they're using a DSP to generate the sine-wave is irrelevant. A sine-wave is a sine-wave is a sine-wave. You could use trained pigeons to produce a sine, and as long as you properly filtered it (and got fast enough pigeons), it would work fine. \$\endgroup\$ – Connor Wolf Apr 23 '14 at 10:45
  • \$\begingroup\$ See also electronics.stackexchange.com/q/104393/4512 \$\endgroup\$ – Olin Lathrop Apr 23 '14 at 13:34

Inverters that produce sine waves are better than those that produce other waveshapes, like square or "modified sine". For a discusion of this, see this question.

In this sense, the "quality" of the signal can be measured by its harmonic content. Ideally, the waveform is a pure sine in phase with the power line and has 0 harmonic content. The power industry has converged on another way of expressing what amounts to the same thing, which is the power factor. This measures the fraction of the overall voltage that is in phase with the power line. A power factor of 1 is therefore ideal. A power factor of 97% or higher is quite good for most purposes, and needs to be reasonably sinusoidal to acheive that.

There is no reason for you to care how a particular inverter achieves low harmonic content or a high power factor, only that it does. Some inverters, probably in fact most of them that produce sine output, have a DSP (digital signal processor) inside controlling the power supply to keep the output sinusoidal. The only difference in this case is that the marketing literature mentions it.

So to recap: First, most inverters with sine wave outputs will have a DSP inside. Second, it doesn't matter anway. All you care about is that the power factor is high enough, or conversely, the harmonic content is low enough. How that is achieved internally is irrelevant to you.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.