zero voltage switching ...relay based stabilizer.....

[jit_singh_tara]

Dear friends ,

I m working on a project :
zero voltage switching ...relay based stabilizer.....

Please suggest any design challenges faced....

So far i have to sense the ac mains voltage ...and based on the voltage , i have to switch the tapping of autotransformer through relay..
Now i am planning to use the zvc optocoupler like moc3061 for switching the relay at zero voltage....Please suggest any practical previous experience..

1.Will the relay create some lag in getting on (which i feel) , in that case though the zvc opto will conduct the relay at zero crossing , but the relay due to its non repeatable characteristic will switch on at some other part of the cycle which will create spark at the contacts ,thus relay life decreases.

2.What about the zvc with triac design , what are the design challenges in that.

Some practical experience sharing is welcome....

Thanks and regards
Jitender Singh

 

[elanshul]

Dear Jitu,
Please find attched here 2 design may be this is useful for you.

 

[FvM]

What means "relay" related to your design?

If you are talking about regular contactors, it's near to impossible to get a precise timing resulting in ZVS operation.

 

[jit_singh_tara]

Dear elanshul ,
Thanks for the design , yes it was useful .....I want to make the design using microcontroller to sense the ac voltage and then switch the moc3041.I got the the switching circuit from you fine .Did you tested the design in the file del20022 , I will be make use of something like this design....Do you know any practical details like the reliability of this ckt ,whether it is running in mkt or just lab tested......I want to know

whether triac based design is better or relay based for switching the winding...

Thanks for your help....

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What means "relay" related to your design?

If you are talking about regular contactors, it's near to impossible to get a precise timing resulting in ZVS operation.

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Dear Fvm ,
I need to switch the winding of the transformer through the 24V dc relays in the stabilizer ,
I want to know which method is reliable and best for stabilizer:

a. relay based switching.
b. triac based switching.


which is the method used nowadays in ac voltage mains stabilizer.
Is the triac switching method practically implemented in the industry ,How much reliable is this design.....

 

[elanshul]

Dear elanshul ,
Thanks for the design , yes it was useful .....I want to make the design using microcontroller to sense the ac voltage and then switch the moc3041.I got the the switching circuit from you fine .Did you tested the design in the file del20022 , I will be make use of something like this design....Do you know any practical details like the reliability of this ckt ,whether it is running in mkt or just lab tested......I want to know

whether triac based design is better or relay based for switching the winding...

Thanks for your help....

- - - Updated - - -

- - - Updated - - -



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Dear Fvm ,
I need to switch the winding of the transformer through the 24V dc relays in the stabilizer ,
I want to know which method is reliable and best for stabilizer:

a. relay based switching.
b. triac based switching.


which is the method used nowadays in ac voltage mains stabilizer.
Is the triac switching method practically implemented in the industry ,How much reliable is this design.....

Dear Jitu Bhai,

I am very thankful to you for sharing the design. Here is some intrusting point about me. I am not a professional in electronics & electrical but I am having a hobbies in electronics & electrical . every thing which I know this is only my own practical knowledge & helps by books. I am working in a telecom company and looking commercial activities here.
The circuit del20022 in not running in market this is only lab tested and one of them is made by me for my household refrigerator.

Relay based switching is better then triac. Triac is not good for inductive load such as equipment using motor like fan, refrigerator, ac etc. a humming sound produce by triac if we use in inductive load. triac is good only for small lighting projects as bulb type load

Now a days microcontroller based circuit widely use for control 90 volt to 290 volt ac mains using 3+1 relay having 95% accuracy. a 5kva stabilizer i am using my self and I got a relief with problem of facing comparator circuit like quad op amplifier LM324 etc.

To get rid of fluctuation in mains and u able to pay more my suggestion is please use servo controller or PWM based stabilizer.

I am trying to find PWM based stabilizer circuit diagram or branded stabilizer for my self also.

 

[jit_singh_tara]

Dear Fvm ,

In this application of digital voltage stabilizer ,
Where we need to switch the windings of auto transformer via triac ....Can you please suggest what would happen if the triacs becomes faulty and gets shorted permanently for say 2 windings ,
I am asking this question because i came to know this that when triac gets blown up there are chances that it becomes short , in such a case the an unwanted tapping can get connected which is not desirable.

Is there a way by which we can make sure that triac malfunction never makes it short , or you can say i dont want the triac to conduct if it fails......
What is the best way to use triac .I will be using moc 3041 along with triac.

thanks