Magnetic Saturation Suppression of Common-Mode Choke Coil by Selecting Suitable Inverter Carrier Frequency

• Published in: IEEJ JOURNAL OF INDUSTRY APPLICATIONS Vol. 142; no. 5; p. 362
• Main Authors: Hasegawa, Kohei, Tokiwa, Tsuyoshi, Kobayashi, Shinji, Takamatsu, Seisho, 光平, 長谷川, 常盤 豪, 伸次, 小林, 誠昇, 高松
• Format: Journal Article
• Language: Japanese
• Published: Tokyo Japan Science and Technology Agency 01.05.2022
• Subjects: Cables; Capacitance; Carrier frequencies; Circuit design; Coils; Inverters; Leakage current; Linear circuits; Magnetic saturation; Pulse duration modulation
• ISSN: 2187-1094; 2187-1108
• DOI: 10.1541/ieejias.142.362

Common-mode choke (CMC) plays an important role in suppressing the leakage current produced during the operation of pulse width modulation (PWM) inverters. However, when the common-mode path exhibits a large series stray capacitance, particularly the capacitance produced by long shielded cables, the CMC core reaches magnetic saturation. This paper presents a technique of selecting a suitable carrier frequency for the inverter to suppress the magnetic saturation of the CMC. First, the analytical approach leads to a non-saturation condition, and clarifies the maximum and minimum carrier frequency design conditions. Subsequently, the effect of the design is demonstrated by a non-linear circuit simulation and experimental tests using an actual inverter system demonstrate the effectiveness of the design technique.