Abstract: A power supply system maintains or controls the output even if multiple power sources include a power source whose optimum output voltage varies. A power supply system includes a direct-current power supply mechanism that supplies direct-current power, a direct-current power storage mechanism that stores direct-current power, and a direct-current output terminal that outputs direct-current power supplied from the direct-current power supply mechanism, the direct-current power storage mechanism, or both to a direct-current load. An output of the direct-current power supply mechanism and the direct-current output terminal are connected directly or through a current backflow prevention mechanism. An input/output terminal of the direct-current power storage mechanism and the direct-current output terminal are connected directly or through a power backflow prevention mechanism.

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: 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 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: 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 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: A playing motion capturing apparatus includes a guitar, a photoreflector, a controller, a piezoelectric pickup, and a personal computer. The photoreflector includes a plurality of full-color LEDs and a plurality of phototransisters, and is disposed in a fingerboard region of the guitar. The photoreflector detects a color of a finger pressing a string, and outputs a position of the finger. The controller turns the full-color LEDs on and off, and outputs light receiving signals of and position information on the phototransister to the personal computer. The piezoelectric pickup detects vibration of the strings and outputs vibration signals to the personal computer.