Experiment of Self-healing Properties of Metallized Films Under Multiple Physical Fields
Metallized film capacitors are core components of the converter valves in flexible high-voltage direct-current(HVDC)transmission systems.Mastering the self-healing parameters of metallized films under complex operating condi-tions is crucial for the development of high-performance capacitors and improving energy transmission efficiency.Based on the actual operating conditions of metallized film capacitors,this paper utilizes a multi-physical field self-healing test-ing platform to conduct self-healing characteristic tests under the combined effects of electrical,thermal,and mechanical stresses.The study reveals the interactive effects of voltage,temperature,and pressure on the self-healing behavior of metallized films.It is found that as the temperature increases,the impact of voltage on self-healing becomes more re-markable;while as the pressure rises,the impact of voltage on self-healing gradually diminishes.When the pressure exceeds 4 MPa,the effect of voltage on self-healing becomes negligible.Through statistical analysis of self-healing char-acteristics,this paper establishes a correlation between self-healing parameters and concludes that the self-healing area and the number of self-healing points are negatively correlated.Specifically,when the number of self-healing points in the effective area increases from 1 cm-2 to 30 cm-2,the average area of a single self-healing point decreases from 16 mm2 to 1 mm2.Furthermore,self-healing current peaks,self-healing time,and self-healing voltage are positively correlated.When the voltage reaches 3.5 kV,the self-healing time can reach 4 μs,and the self-healing current peak can reach 5 A.The self-healing energy follows a power function with an exponent of 2.316 relative to the self-healing voltage.Based on the established correlation between self-healing parameters,this paper also proposes a rapid estimation method for self-healing energy.The research involves key characteristic parameters and criteria for the performance of metallized film materials,providing valuable data supports for the optimized design of metallized film capacitors.
万方数据
维普
