Influence of frequency on the surface discharge characteristics of PEEK under positive repetitive square voltage

Abstract

In this study, the surface discharge current pulses of polyetheretherketone (PEEK) material under positive repetitive square voltage in a nitrogen atmosphere are measured. The influences of different voltage amplitudes and frequencies on the detail parameters of forward discharge and backward discharge current pulses are statistically analysed. The results show that as the square voltage amplitude increases, the current pulse amplitude, fall time and pulse width of both forward and backward discharge current increase, and the rise time does not change significantly. As the voltage frequency increases, current pulse amplitude, fall time and pulse width of both forward and backward discharge current decrease, and the rise time does not change significantly. Due to the independence of the discharge at different repetitive cycles, the specific discharge process in one cycle is analysed in detail to explain the influence mechanism of the voltage amplitude and frequency on the discharge current. By mean of the Richardson–Schottky and the Cavallini relaxation model, the relationship between discharge voltage ratio and surface charge, and the decay process of surface discharge are analysed. Furthermore, the influences of amplitude and frequency of the positive repetitive square voltage on the PEEK surface current pulses are explained qualitatively.

Streamer‐to‐precursor transition in N 2 –SF 6 mixtures under positive repetitive submicrosecond pulses

“…SF 6 ) are often added. Concerns about greenhouse gas emissions have arisen recently [8][9][10]. Unlike relatively repeatable discharge behaviours under single-shot pulse, gas discharges excited by repetitive pulses exhibit complicated (sometimes unpredictable) evolution processes.…”

Transient electric field of the combined insulation structure under positive periodic square waveform voltage: Analytical analysis and application

“…The extensive application of the PPSW voltage has attracted attention of many researchers. In experimental studies, extensive efforts have been made to obtain the partial discharge characteristics of power electronics [9,10], the surface charge characteristics [11][12][13], the streamer characteristics [14], accumulation and dissipation of the space charge characteristics [15,16] of engineering insulation materials. Significant progress has been achieved to investigate the dependence of waveform parameters of the PPSW voltage on space charge accumulation characteristics [17], partial discharge characteristics [18], surface discharge characteristics [19], and electric tree characteristics [20,21] of insulation materials.…”

Pulse width modulation voltage source deadtime effect on partial discharge and lifetime of inverter‐fed motor insulation

“…When electrical stress exceeds the partial discharge inception voltages (PDIV), PD occurs and this PD can accelerate the electrical ageing of the motor insulation causing insulation failure [1,2]. The complexity of impulse voltage parameters such as frequency, rise time and deadtime can influence PD and endurance features [3][4][5]. High-frequency impulse voltage with fast rise time from converters can cause premature failure in the insulation system of inverter-fed motors.…”