Abstract: Disclosed is a power generation system provided with a renewable-energy-based electric power generator, capable of efficiently and stably outputting electric power at a predetermined power amount. The power generation system includes at least an electric power generator and a maximum power amount detection control unit that performs control such that a voltage and a current at the maximum power point can be detected at any time to output the result as a detection value. The power supplied from a variable voltage power source is selected when the voltage is short. In contrast, the power supplied from a constant voltage power source is selected when the current is short.

Abstract: A power transmission system, which has a plurality of DC power sources and a load that receives a supply of DC power, is characterized in that: a power priority retrieving device is attached to each DC power source; control is performed by a controller; and the amount of power to be delivered from a DC power source to which a power priority retrieving device is attached to the load is determined on the basis of the retrieved power priority.

Abstract: When using DC power supplies, turning off switches and unplugging from sockets can result in arc discharge, and when arc discharge occurs, heat is generated, which can cause damage to contacts, wiring of disconnection points to melt, and fires. In order to solve this problem, an object is to prevent inrush current when connecting a power supply, detect arc discharge generated when disconnecting direct current, and stop arc discharge over a short period of time. All of the loads that are connected to a DC power supply are equipped with a soft-start function that gradually and smoothly increases current so as to prevent current from flowing suddenly when connected to a power supply, and if a sudden drop in the power supply voltage is detected, an arc discharge is deemed to have occurred, and the flow of current from the power supply to the load is cut off immediately.

Abstract: A power source apparatus that combines power generated by a photovoltaic system and power generated from another power source by using a power combiner and transmits the combined power to a load side, wherein an output voltage of the photovoltaic system can be changed by changing a cell connection state of a plurality of solar cells of the photovoltaic system, and the highest efficiency of the photovoltaic system can be obtained by adding the output voltage of the photovoltaic system to an output voltage of the another power source.

Abstract: A direct-current power supply utilizing system includes: at least one direct-current power supply that produces a direct-current output; an alternating-current commercial power supply; a direct-current converter that converts the alternating-current commercial power supply into direct-current power; and a direct-current load device that receives supply of direct-current power from both at least one direct-current power supply and the commercial power supply which has been converted into direct-current power, where a back-flow prevention diode is individually connected between the at least one direct-current power supply and the direct-current load device and between the direct-current converter and the direct-current load device, and a power supply priority supply device that preferentially supplies power to the direct-current load device from the side of the direct-current power supply is connected.