Patent application number | Description | Published |
20090283128 | Method and system for activating and deactivating an energy generating system - A method for activating a local converter for one of a plurality of energy generating devices in an energy generating array is provided. The local converter includes a power stage and a local controller. The method includes comparing a device voltage for the energy generating device to a voltage activation level. The local converter is automatically activated when the device voltage exceeds the voltage activation level. | 11-19-2009 |
20090284078 | System and method for integrating local maximum power point tracking into an energy generating system having centralized maximum power point tracking - A system for integrating local maximum power point tracking (MPPT) into an energy generating system having centralized MPPT is provided. The system includes a system control loop and a plurality of local control loops. The system control loop comprises a system operating frequency, and each local control loop comprises a corresponding local operating frequency. Each of the local operating frequencies is spaced apart from the system operating frequency by at least a predefined distance. For a particular embodiment, a settling time corresponding to the local operating frequency of each local control loop is at least five times faster than a time constant corresponding to the system operating frequency. | 11-19-2009 |
20090284232 | Method and system for selecting between centralized and distributed maximum power point tracking in an energy generating system - A method for selecting between centralized and distributed maximum power point tracking in energy generating system is provided. The energy generating system includes a plurality of energy generating devices, each of which is coupled to a corresponding local converter. Each local converter includes a local controller for the corresponding energy generating device. The method includes determining whether the energy generating devices are operating under quasi-ideal conditions. The energy generating system is placed in a centralized maximum power point tracking (CMPPT) mode when the energy generating devices are operating under quasi-ideal conditions and is placed in a distributed maximum power point tracking (DMPPT) mode when the energy generating devices are not operating under quasi-ideal conditions. | 11-19-2009 |
20090284240 | Method and system for providing local converters to provide maximum power point tracking in an energy generating system - A method for providing maximum power point tracking for an energy generating device using a local buck-boost converter coupled to the device is provided. The method includes operating in a tracking mode, which includes initializing a conversion ratio for the buck-boost converter based on a previous optimum conversion ratio. A device power associated with the initialized conversion ratio is calculated. The conversion ratio is repeatedly modified and a device power associated with each of the modified conversion ratios is calculated. A current optimum conversion ratio for the buck-boost converter is identified based on the calculated device powers. The current optimum conversion ratio corresponds to one of a buck mode, a boost mode and a buck-boost mode for the buck-boost converter. | 11-19-2009 |
20090284998 | Method and system for providing maximum power point tracking in an energy generating system - A method for providing a maximum power point tracking (MPPT) process for an energy generating device is provided. The method includes coupling a local converter to the energy generating device. A determination is made regarding whether the local converter is operating at or below a maximum acceptable temperature. A determination is made regarding whether at least one current associated with the local converter is acceptable. When the local converter is determined to be operating at or below the maximum acceptable temperature and when the at least one current associated with the local converter is determined to be acceptable, the MPPT process is enabled within the local converter. | 11-19-2009 |
20100039840 | AC-TO-DC VOLTAGE CONVERSION AND CHARGING CIRCUITRY - Voltage conversion and charging circuitry and method for converting an alternating current (AC) voltage to a direct current (DC) voltage for charging an energy storage element (e.g., battery or supercapacitor). An output capacitance, which is initially charged quickly for use in the slower charging of a battery, also maintains the charge on an input capacitance which provides power for the charging control circuitry during such charging process. In accordance with a preferred embodiment, the DC charging current is substantially constant during a first time interval following which the DC charging power is substantially constant during a second time interval. | 02-18-2010 |
20100288327 | System and method for over-Voltage protection of a photovoltaic string with distributed maximum power point tracking - A string over-voltage protection system and method for arrays of photovoltaic panels. The system and method includes a device for use in a photovoltaic array power system. The device includes a voltage converter. The voltage converter is adapted to be coupled to a photovoltaic panel in a string of photovoltaic panels. The device also includes a string over-voltage protection circuit. The string over-voltage protection circuit is coupled to the voltage converter. The string over-voltage protection circuit senses a string voltage and determines if a string over-voltage condition exists. Additionally, the string over-voltage protection circuit is configured to disable the voltage converter in the event of a string over-voltage condition. | 11-18-2010 |
20100327659 | SYSTEM AND METHOD FOR OVER-VOLTAGE PROTECTION OF A PHOTOVOLTAIC SYSTEM WITH DISTRIBUTED MAXIMUM POWER POINT TRACKING - A solar panel array for use in a solar cell power system is provided. The solar panel array includes a string of solar panels and multiple voltage converters. Each voltage converter is coupled to a corresponding solar panel in the string of solar panels. The solar panel array also includes multiple maximum power point tracking (MPPT) controllers. Each MPPT controller is coupled to a corresponding solar panel in the string of solar panels. Each MPPT controller is configured to sense an instantaneous power unbalance between the corresponding solar panel and an inverter. | 12-30-2010 |
20110115436 | ACTIVE CELL AND MODULE BALANCING FOR BATTERIES OR OTHER POWER SUPPLIES - A system includes multiple power modules, each having multiple power cells coupled in series. Each power module has a charge that is based on charges of the power cells in that power module. The system also includes multiple active cell balancing circuits, each configured to substantially balance the charges of the power cells in an associated one of the power modules. The system further includes an active module balancing system configured to substantially balance the charges of the power modules by charging a first subset of the power modules and/or discharging a second subset of the power modules. The active module balancing system could include multiple module balancing circuits, each associated with one of the power modules and configured to charge or discharge its associated power module. A direct current (DC) bus can be configured to transport DC power between the module balancing circuits. | 05-19-2011 |
20140232346 | ACTIVE CELL AND MODULE BALANCING FOR BATTERIES OR OTHER POWER SUPPLIES - A system configured to actively balance power among power cells such as batteries. The system includes a power module of series-coupled power cells, each exhibiting different charge levels during charging and discharging. A power module includes active cell balancing circuitry configured to substantially balance the charges of the power cells at least during charging. In one embodiment, the active cell balancing circuitry includes: (a) current source circuitry configured to supply extra charging current to a selected power cell; and (b) current source control circuitry configured to control the current source circuitry to supply extra charging current to the power cell with the lowest state of charge. In another embodiment, the system includes multiple power modules, each having multiple power cells coupled in series, and each having an active cell balancing circuit configured to substantially balance the charges of the power cells in an associated one of the power modules. | 08-21-2014 |