US Patent 9184312 Solar power generation device

A transmitting circuit is connected to a power line at current flow-in sides to solar battery strings, and a receiving circuit is connected to the power line at current flow-out sides to the solar battery strings. An attenuating circuit connected in series to a bypass diode is provided in a bypass circuit. The transmitting circuit transmits a periodic signal of a predetermined frequency to the power line. The receiving circuit receives via the solar battery strings a transmission signal transmitted from the transmitting circuit to the power line. A determining circuit determines that, when it is detected that an amplitude of a transmission signal received by the receiving circuit is attenuated by a predetermined value or more, direct-current power is conducted to the bypass circuit.