National Semiconductor Corporation

Jianhui Zhang

Ali Djabbari

Gianpaolo Lisi

David I Anderson

Barry Signoretti

Ahmad Reza Bahai

Gerard G Socci

Frank Trautmann

Kosha Mahmodieh

Rajaram Subramoniam

Martin Embacher

Christian Giassner

Qingguo Liu

Andrew Ronald Chemistruck

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.

Method and system for activating and deactivating an energy generating system

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.

System and method for over-voltage protection of a photovoltaic system with distributed maximum power point tracking

A buck/boost regulator controller is provided. The buck-boost regulator controller controls four switches in an H-bridge configuration to control voltage regulation. The buck/boost regulator controller includes a digital error amplifier and buck-boost control logic. The digital error amplifier provides a multi-bit digital error voltage signal that is based on the difference between the output voltage and the desired output voltage. The buck-boost control logic controls the opening and closing of the four switches in the H-bridge based, in part, on the multi-bit digital error voltage signal.

Apparatus and method for digitally controlled buck-boost switching regulator

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.

Method and system for providing maximum power point tracking in an energy generating system

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.

System and method for integrating local maximum power point tracking into an energy generating system having centralized maximum power point tracking

The invention relates to an apparatus and method for driving high-side switching devices in an H-Bridge circuit. The apparatus includes first and second N-Channel high-side switching devices. Each of the high-side switching devices is associated with, and is selectively driven by, a driver circuit. Each of the driver circuits is associated with, and is powered from, a bootstrap capacitor. The apparatus further includes a cross-couple circuit that is arranged to charge each of the bootstrap capacitors based, at least in part, on whether the low-side switching device that is associated with the other bootstrap capacitor is open or closed.

Bootstrap circuit for H-bridge structure utilizing N-channel high-side fets

A method for selecting between centralized and distributed maximum power point tracking in an 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 that includes a local controller. The method includes determining whether there is at least a threshold amount of mismatch between operating characteristics of the energy generating devices. The energy generating system is placed in a centralized maximum power point tracking (CMPPT) mode when there is not at least the threshold amount of mismatch and is placed in a distributed maximum power point tracking (DMPPT) mode when there is at least the threshold amount of mismatch.

Method and system for selecting between centralized and distributed maximum power point tracking in an energy generating system

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.

AC-to-DC voltage conversion and charging circuitry

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.

Method and system for providing local converters to provide maximum power point tracking in an energy generating system

A central array controller for an energy generating array is provided. The array includes a plurality of energy generating devices, and each energy generating device is coupled to a corresponding local converter. The central array controller includes a diagnostic module that is capable of receiving, from each local converter in the array, device data for the energy generating device corresponding to the local converter. In one embodiment, the diagnostic module is also capable of receiving, from each local converter in the array, local converter data for the local converter.

Method and system for providing central control in an energy generating system

A circuit for voltage regulation is provided. The circuit includes a variable output voltage regulator and an output capacitor circuit. The output capacitor circuit includes at least two output capacitors and at least one switch. The variable output voltage regulator is capable of providing a regulated DC output voltage at two or more different voltage levels. When the output voltage is changed to a lower output voltage level, one of the output capacitors in the output capacitor circuit is switched out of the circuit to conserve the charge stored on it. When the output voltage returns to the higher output voltage level, the output capacitor that was switched out is switched back in.

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San Jose, CA, United States of America

Jianhui Zhang