EARTH FAULT DETECTION DEVICE

• Main Authors: HORI FUMIHIKO, MIZOGUCHI HAYATO, MAEHARA TSUNEO, KUBO SHUNICHI
• Format: Patent
• Language: English; Japanese
• Published: 24.01.2019
• Subjects: CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRIC EQUIPMENT OR PROPULSION OF ELECTRICALLY-PROPELLEDVEHICLES; ELECTRICITY; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES, IN GENERAL; EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS; GENERATION; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; PERFORMING OPERATIONS; PHYSICS; TESTING; TRANSPORTING; VEHICLES IN GENERAL

To provide an earth fault detection device for appropriately detecting an earth fault regardless of the magnitude of floating capacitance.SOLUTION: An earth fault detection device 10 comprises: a coupling capacitor Cs connected to a battery 20; a resistance circuit Rs serially connected to the coupling capacitor Cs, and configured such that the magnitude of resistance is variable; and an oscillation circuit 12 for applying an AC voltage to the resistance circuit Rs. Also, the earth fault detection device 10 comprises a CPU 11, and the CPU 11 has: a function for varying the magnitude of the resistance in the resistance circuit Rs; and a function for detecting an earth fault on the basis of a voltage difference at a junction point P when the AC voltage is applied before and after the magnitude of the resistance in the resistance circuit Rs is varied.SELECTED DRAWING: Figure 1 【課題】浮遊容量の大きさによらず、地絡を適正に検出する地絡検出装置を提供すること。【解決手段】地絡検出装置１０は、バッテリ２０に接続されるカップリングコンデンサＣｓと、カップリングコンデンサＣｓに直列接続され、抵抗の大きさを可変に構成された抵抗回路Ｒｓと、抵抗回路Ｒｓに交流電圧を印加する発振回路１２を備える。また、地絡検出装置１０は、ＣＰＵ１１を備え、ＣＰＵ１１は、抵抗回路Ｒｓにおける抵抗の大きさを変化させる機能と、抵抗回路Ｒｓにおける抵抗の大きさの変化前後において、交流電圧を印加した場合における接続点Ｐでの電圧差に基づき、地絡を検出する機能を有する。【選択図】 図１