Advanced Analysis of Voltage Rise Phenomena in Electrically Floating HV Power Platforms.

Abstract:
Voltage rise in electrically floating high-voltage, high-power DC power supplies can result from capacitive coupling or leakage across isolation barriers. Despite the use of isolation components such as transformers, optocouplers, and insulating materials, parasitic elements may introduce paths for charge accumulation over time. This leads to a non-zero potential between the floating output and ground, which can pose safety and performance risks. This paper presents a detailed investigation into the mechanisms contributing to such voltage buildup. Analytical models and circuit-level simulations are developed to predict the magnitude of the voltage rise under various conditions. The models are validated through experimental measurements on a 200 kW, 5000 V floating DC power supply. Results provide practical insights into voltage accumulation behaviour and offer guidance for system design and mitigation