Dear Friends,
I am facing transients in my electrical supply line. I am attaching the waveform of this transient voltage. Kindly let me know how to overcome this issue. I already installed SPD but problem is still there.

 

There is something called a constant voltage transformer but they are not cheap.

 

This type of noise maybe caused by light dimmers, computers and monitors.

 

You haven't stated what the Load consists of, and why the Noise is a problem.

What problem are You trying to solve, specifically ?

If the Power is run through a 3-Phase- Isolation-Transformer,
most of the high-Frequency-Noise will be filtered-out,
or,
If what You need is a DC-Power-Supply,
the Noise should be filtered-out by the Step-down-Transformer,
and the required Bulk-Storage-Capacitors.
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.

 

You haven't stated what the Load consists of, and why the Noise is a problem.

What problem are You trying to solve, specifically ?

If the Power is run through a 3-Phase- Isolation-Transformer,
most of the high-Frequency-Noise will be filtered-out,
or,
If what You need is a DC-Power-Supply,
the Noise should be filtered-out by the Step-down-Transformer,
and the required Bulk-Storage-Capacitors.
.
.
.

Dear Sir,
This is the waveform obtained from the 125kW solar inverter. Recently we have installed total 600kW solar (5 inverter of 125kW each). Out of 5, one of the inverter malfunctioned and the inverter supplier email us this waveform and request from us to install surge protection device. Our plant was operating smoothly at that time when this inverter malfunctioned, furthermore no evidence of high voltage found in our power analyzer Lovato DMG 9000.
We have already installed SPD in our main LT panel and SMDB.

 

How are You synchronizing 5- 3-Phase-Converters ?

If the Converters are not specifically designed to synchronize to each other,
You will have switching-noise that can not be avoided.

If it is not causing problems with the equipment being powered,
then don't worry about it,
it obviously hasn't blown-up anything as of yet.

If You have further questions ...........
You must provide a more comprehensive set of questions.

If You have further questions ............
Please provide any and all Specification, and/or, Installation, PDFs as attachments.
Otherwise, all we can do is guess and assume, which may get us nowhere, and waste a lot of time.
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