MCE has designed and manufactured a large variety of high frequency-high voltage transformers, this includes those that have a high voltage bias and those that generate high voltage.
If the high voltage bias is DC, the insulation resistance must be high at the high voltage to minimize leakage current. The insulating materials must be chosen to have high volume resistivity at the maximum operating temperature.
When the high voltage bias is AC, there is an additional requirement. Parts must be tested for corona. This may require encapsulation, especially with small parts.
There are various winding techniques that will increase the reliability of high voltage transformers. Testing parts for corona inception voltage is a must to ensure long life. This test is one which predicts the future. A part may pass a dielectric withstanding test, and fail because of corona. One approach that will make the transformer smaller and at less cost is to use voltage multipliers for DC output with moderate loads.
In those cases where encapsulation may be required, choice of encapsulating compound is critical. Furthermore, a very low viscosity is necessary to penetrate windings.
MCE uses Computer Aided Design programs which provide designs rapidly and inexpensively. Materials especially suited for high voltage applications are stocked. Experience with these designs and materials is especially important to achieve long term reliability. MCE recommends discussing specifications with an Application Engineer before finalizing.