caution to take; AC input for SMPS/Charger through generator

[Vindhyachal.takniki]

1. We need to install a SMPS based lithium battery chargers 29.2V/15A in a system.

2. System is always powered by generator, which runs around 6 hours a day. Seems a bit old type of generator, we measured its output, it fluctuates between 180-250vac at different loads.
Freq variation is 45-55hz this is not measured but told by user.
Depending upon what kind of load in nearby system, voltage spikes may be high.

3. We opened up earlier system which got damaged, it had two circuits before their SMPS, a voltage correction & a frequency correction system as written on them. they were potted so cannot check what inside it.

4. Now we have to replace system. I think the freq correction is not required, as it is SMPS based & we have to convert ac to dc here.

5. For voltage correction, is there aby ready to use circuit/board which we can use. As we were able to check only for few load types the generator outout, it may fluctaute more.

6. Can we add a freq corection ckt also here?

7. What are the other precuations to take before SMPS?

[fourtytwo42]

Depending upon the type of SMPS frequency is not an issue, certainly one without power factor correction and a straight rectifier input. Most SMPS operate over a wide input voltage range it's simply a case of matching the SMPS specification to your application, you have already stated the input conditions here.
There is a possibility of voltage surges when generator loads are switched off and you may need some additional voltage surge suppressors such as http://uk.rs-online.com/web/p/surge-suppressor-units/2266448/ to protect the SMPS input.

[Vindhyachal.takniki]

Since the output is coming from generator, we have decided to use a Constant voltage transformer or servo stabilizers to protect our system.

[Brumby]

Depending upon the type of SMPS frequency is not an issue, certainly one without power factor correction and a straight rectifier input. Most SMPS operate over a wide input voltage range it's simply a case of matching the SMPS specification to your application, you have already stated the input conditions here.
There is a possibility of voltage surges when generator loads are switched off and you may need some additional voltage surge suppressors such as http://uk.rs-online.com/web/p/surge-suppressor-units/2266448/ to protect the SMPS input.

I agree.  A SMPS should be able to operate over your frequency and voltage ranges without any difficulty - it will be just a matter of ensuring a robust design and covering any transient issues.

Going with an intermediate transformer step seems unnecessary - unless it is required for other systems on the generator fed supply.

That is, of course, unless you are limited to off-the-shelf solutions.

[oldway]

Be aware that output voltage of a Constant voltage transformer is frequency depending.....

Check if it will not exceed the max input voltage of the SMPS charger.