A system and method for combining power from DC power sources. Each power source is coupled to a converter. Each converter converts input power to output power by monitoring and maintaining the input power at a maximum power point. Substantially all input power is converted to the output power, and the controlling is performed by allowing output voltage of the converter to vary. The converters are coupled in series. An inverter is connected in parallel with the series connection of the converters and inverts a DC input to the inverter from the converters into an AC output. The inverter maintains the voltage at the inverter input at a desirable voltage by varying the amount of the series current drawn from the converters. The series current and the output power of the converters, determine the output voltage at each converter.

Distributed Power Harvesting Systems Using DC Power Sources

A monitoring system and method for monitoring performance of individual powers sources in a distributed power source system A monitoring module is coupled to each of the power sources, or to each string of serially connected power sources, to monitor and collect data regarding current, voltage, temperature and other environmental factors at the power source The collected data is transmitted over a power line to a central analysis station for analysis Data collected from each source indicates malfunction or degradation at the source Comparison of data collected from adjacent sources filters for environmental factors impacting neighboring sources such as cloudy days for a solar panel Comparison of data collected from the same source at different times indicates soiling or degradation of the source with time or periodic events such as a moving shade from an adjacent building

Monitoring of Distributed Power Harvesting Systems Using DC Power Sources

Method for distributed power harvesting using DC power sources

This invention is generally concerned with power supply circuits, and more particularly, with circuits to supply power to a mains supply, such as domestic grid mains, from a photovoltaic device. A photovoltaic power conditioning circuit for providing power from a photovoltaic device to an alternating current mains power supply line, the circuit comprising: a DC input to receive DC power from said photovoltaic device; an AC output configured for direct connection to said AC mains power supply line; a DC-to-AC converter coupled to said DC input and to said AC output to convert DC power from said photovoltaic device to AC power for output onto said power supply line; and an electronic controller directly coupled to said power supply line to measure a voltage of said power supply line and a current in said supply line and to control said DC-to-AC converter responsive to said measuring.

Power supply circuits

A distributed power system including multiple DC power sources and multiple power modules. The power modules include inputs coupled respectively to the DC power sources and outputs coupled in series to form a serial string. An inverter is coupled to the serial string. The inverter converts power input from the serial string to output power. A signaling mechanism between the inverter and the power module is adapted for controlling operation of the power modules.

Safety mechanisms, wake up and shutdown methods in distributed power installations

PROBLEM TO BE SOLVED: To provide a solar power generating device having a maximum power point tracking function capable of accurately detecting a maximum power point even when the output power-output voltage characteristic of a solar battery has a plurality of peaks without making the output voltage and output power of the solar battery fluctuate needlessly. SOLUTION: An output power-output voltage characteristic detecting means CD1 provided with a solar battery PV1 having the same environmental condition as a main solar battery PV2 is provided apart from a main generation circuit. Then, an output voltage controlling means CT1 obtains the numerical data of the output power-output voltage characteristic of the battery PV1 for characteristic detection by turning a switch SW on or off and detects a maximum power point. Then, control signals S1a to S1d are given to respective transistors T1 to T4 of a voltage type inverter IV1 so that the main solar battery PV2 can generate a voltage value corresponding to the detected maximum power point.

Solar battery controller and solar power generating device

Fast- switching reverse-conducting thyristors have been developed and used in dc chopper apparatus to control the speed of highvoltage dc traction motors. The newly developed dc chopper circuit and its application for low-voltage dc motor control are discussed. The fast-switching reverse-conducting thyristor is utilized as the main thyristor to control load current.

Takahiko Iida

Papers

Solar battery controller and solar power generating device

New DC Chopper Circuits Using Fast-Switching Reverse-Conducting Thyristors for Low-Voltage DC Motor Control

Protective device for inverter