Study on the relationship between decomposition characteristic components of SF6 and partial discharge quantities

To get relationship between SF₆ decomposition characteristic and partial discharge capacity or discharging repetition rate, needle-plate electrode was used to simulate out-thrust insulation fault and serials of experiments were conducted. The result showed that: since the number of C atoms from stainless steel surface and content of trace H₂O and O₂ in gas chamber were limited, the decomposed component concentration and its effective formation rate appeared “Logistic Population Model” growth trend with the enhancement of per second discharging capacity (Q_sec). It means they present “S”-curve increase with Q_sec. Hence, this paper proposed C(S0₂F₂)/C(SOF₂) as the characteristic ratio (ER) to represent partial discharge energy. Besides, it defined effective energy characteristic ratio (ER_RMS) and provided the relationship between ER_rms and Q_sec. It further obtained relationship mathematic expression between them, which could effectively show the variance regularity of partial discharge energy with Q_sec.