Prediction of voltage build up in an electrically floating high voltage high power supply.

Abstract:
In electrically floating high-voltage, high-power DC power supplies, unintended voltage build-up can occur due to capacitive coupling between the input and output or leakage through isolation components. The isolation in such systems is typically implemented using transformers, optocouplers, high-voltage insulation materials, or other isolation devices. However, any leakage current across the isolation barrier, parasitic capacitance between the input and output, or capacitance between the output and ground can result in a gradual accumulation of voltage on the floating output with respect to ground. This uncontrolled voltage build-up poses potential operational and safety hazards. This paper presents a detailed analysis of the key factors influencing voltage build-up in floating high-voltage power supplies. A quantitative approach is employed, incorporating analytical calculations and simulation-based modeling to predict voltage accumulation under various conditions. The theoretical findings are validated experimentally using a 200 kW, 5000 V DC floating power supply, providing practical verification of the predicted voltage behavior. The results contribute to a deeper understanding of voltage build-up mechanisms in electrically floating systems and inform effective mitigation strategies for high-voltage power supply design.