Hello Manoj,

I think, what capacitor you are referring to as 103Z 1kV is a small disc capacitor or 10nF (0.01uF) rated for 1kV (or 1000VDC). As a matter a standard practice, you should choose a capacitor that is rated twice than your normal working voltage (in your circuit)  as the voltages are specified to be DC. When working in AC circuits pay attention to the RMS (AC) voltage and this should be less than what the capacitor is rated for (the DC voltages).

Kindly also note that as the operating or rated voltage increases (in kV range) the value of the capacitors drops to nF and not in uF range.

Vishay has some good Ceramic (single layer) capacitors that are rated for 10kV or higher voltage ratings. Also there are other manufacturers that manufacture these high voltage capacitors.

Thanks and Best Luck!

Dear Prasanna,

Thanks a lot for your valuable answer. Keep in touch. Actually m designing a high voltage converter (approx. 1.8kV) for charging a liquid spray inductively. The fact is, it is application specific design for electrostatic nozzle. 

Thanks 

That way Manoj, you can just give a small push to your trials. A long time back a Circuit-Idea of Car Air Ionizer appeared in Electronics For You (EFY). This is a relatively simple circuit with a series of diodes and HV capacitors to generate the HV. You can use those 2kV ceramic discs in that circuit to generate the HV for ionizing purposes. This should be a fairly less complex and ideally LOW COST circuit for your application.

Go search for EFY Projects back volumes and you should have no problem in locating the actual circuit diagram.

Best Luck again!

Dear Prasanna,

Sir I am using 1kV (0.01u) ceramic capacitors and these are working well for generating 1.8 kV high voltage for the said purposes. I am trying to reduce the micro Farad to Nano Farad to reduce the load current and ripple of the supply. 

Thanks