Filter device and electric-vehicle drive controller

A filter device that is provided between an overhead line and an inverter that receives power from the overhead line, the filter device comprising:

• a first filter capacitor that is provided in parallel to a direct-current unit of the inverter between a high-potential side bus of the direct-current unit of the inverter and a low-potential side bus of the direct-current unit of the inverter;
• a second filter capacitor that is provided to be closer to a side of the overhead line than the first filter capacitor and that is provided in parallel to the first filter capacitor between the high-potential side bus and the low-potential side bus;
• a first filter reactor that is provided on the high-potential side bus between the first filter capacitor and the second filter capacitor;
• a second filter reactor that is provided on the high-potential side bus between the second filter capacitor and the overhead line, and is magnetically coupled to the first reactor;
• a circuit disconnecting unit that is serially connected to the second filter capacitor between a connection point of the first filter reactor and the second filter reactor that are magnetically coupled to each other and the low-potential side bus;
• and
• a specified-frequency bypass filter that removes a noise current of a specified frequency, in which a bypass circuit disconnecting unit, a bypass inductance element, and a bypass capacitance element are connected in series, wherein
• the specified-frequency bypass filter is provided between the high-potential side bus and the low-potential side bus, and is provided in parallel to the first filter capacitor and the second filter capacitor, where one end of the specified-frequency bypass filter is connected between the overhead line and the second filter reactor or between a high-potential side of the first filter capacitor and the first filter reactor and the other end of the specified-frequency bypass filter is connected to the low-potential side bus,
• the circuit disconnecting unit disconnects between the connection point of the first filter reactor and the second filter reactor and the low-potential side bus when a current larger than a rated current flows in the circuit disconnecting unit, and the circuit disconnecting unit blocks a short-circuit current flowing through the second filter capacitor;
• and
• the bypass circuit disconnecting unit disconnects between the one end of the specified-frequency bypass filter and the other end of the specified-frequency bypass filter when a current larger than a rated current flows in the bypass circuit disconnecting unit, and the bypass circuit disconnecting unit blocks a short-circuit current flowing through the bypass capacitance element.