Patents Assigned to Draker, Inc.
  • Patent number: 9142960
    Abstract: A converter unit to improve overall recovered power in a photovoltaic array configuration. Each photovoltaic panel in the photovoltaic array may be coupled to a respective converter unit, which may include a controller to sense an output voltage and output current produced by the solar panel, and manage the output voltage of a corresponding power converter to optimize and regulate the resultant bus voltage to a point which reduces overall system losses, maintains a low loss condition, and removes series-string non-idealities when the panels are series connected. The controller may also adapt to output condition constraints. Instead of single-port regulation, a combination of input voltage and output voltage management and regulation may be performed within the converter. The source voltage and current characteristic may be shaped to correspond to an optimized power curve at the desired bus voltage to allow MPPT tracking according to the DC voltage bus.
    Type: Grant
    Filed: February 3, 2011
    Date of Patent: September 22, 2015
    Assignee: Draker, Inc.
    Inventors: Bertrand J. Williams, Sam B. Sandbote
  • Patent number: 9106105
    Abstract: A converter unit configured to couple to a photovoltaic panel (PV) may include a controller to sense an output voltage and output current produced by the photovoltaic panel, and manage the output voltage of a corresponding power converter coupled to a DC bus to regulate the resultant bus voltage to a point that reduces overall system losses, and removes non-idealities when the panels are series connected. The controller may also adapt to output condition constraints, and perform a combination of input voltage and output voltage management and regulation, including maximum power point tracking (MPPT) for the PV. The output voltage and output current characteristic of the power converter may be shaped to present a power gradient—which may be hysteretically controlled—to the DC bus to compel an inverter coupled to the DC bus to perform its own MPPT to hold the DC-bus voltage within a determinate desired operating range.
    Type: Grant
    Filed: January 31, 2012
    Date of Patent: August 11, 2015
    Assignee: Draker, Inc.
    Inventors: Shawn R. McCaslin, Sam B. Sandbote, Bertrand J. Williams
  • Patent number: 8975783
    Abstract: A converter unit to improve the response dynamics and overall recovered power in a photovoltaic array configuration. Each photovoltaic panel in the photovoltaic array may be coupled to a respective converter unit, which may include a controller to sense an output voltage and output current produced by the solar panel, and control operation of a power converter to output modified voltage and current corresponding to the solar panel onto a bus coupling the converter units. The controller may operate as an analog or (digital) firmware control system to regulate the input voltage of each power converter unit under indirect guidance of a Maximum Power Point Tracking (MPPT) controller to optimize and regulate the resultant power, and achieve very fast dynamic response to environmental transients.
    Type: Grant
    Filed: January 20, 2011
    Date of Patent: March 10, 2015
    Assignee: Draker, Inc.
    Inventors: Bertrand J. Williams, Sam B. Sandbote
  • Patent number: 8970068
    Abstract: A converter unit configured to couple to a photovoltaic panel (PV) may include a controller to sense an input voltage and input current obtained from the photovoltaic panel, and manage the output voltage of a corresponding power converter coupled to a DC bus to regulate the resultant bus voltage to a point that reduces overall system losses, and removes non-idealities when the panels are series connected. The controller may also perform input voltage management and regulation, including maximum power point tracking (MPPT) for the PV. The controller may probe the bus voltage using a probe waveform generated according to a pseudo-random bit sequence (PRBS), to provide a probe signal that is distinct from the control steps performed by the controller. A PV array may feature a respective converter unit coupled to each PV, with each respective controller using a different and unique seed for generating its PRBS.
    Type: Grant
    Filed: January 27, 2012
    Date of Patent: March 3, 2015
    Assignee: Draker, Inc.
    Inventors: Shawn R. McCaslin, Bertrand J. Williams
  • Publication number: 20140306542
    Abstract: A module for connecting (or coupling) and disconnecting (or decoupling) a photovoltaic panel (PV) to and from other PV panels in a string of PV panels. The module may include first circuitry for detecting when a voltage output by the PV panel (Vpanel) collapses, and second circuitry for disconnecting the PV panel from the panel string while preventing a transistor switching device (e.g. a power MOSFET) performing the disconnecting (decoupling) operation from entering the linear operating region. The combination of low-voltage detection in the first circuitry, and latching-switching in the second circuitry ensures that the power MOSFET is either fully turned on, coupling the PV panel to the panel string, or fully turned off, decoupling the PV panel from the panel string. The PV panel may be recoupled to the PV string through a connection-check mechanism that reengages the PV panel once Vpanel has returned to normal operating levels.
    Type: Application
    Filed: April 11, 2013
    Publication date: October 16, 2014
    Applicant: Draker, Inc.
    Inventor: Bertrand J. Williams
  • Patent number: 8716999
    Abstract: A converter unit configured to couple to a photovoltaic panel may include a controller that monitors: an output voltage and output current obtained from the photovoltaic panel by a switching power core within the converter unit, and an output voltage and output current produced by the switching power core. The controller may calculate a desired duty-cycle value based on the monitored values, and implement a mapping algorithm that translates the duty-cycle value to a pulse-width value and a modulus value. The pulse-width value and the modulus value may be used to simultaneously respectively modulate the pulse-width and pulse-period of a pulse-width modulated (PWM) signal, while maintaining an appropriate linear final duty-cycle ratio between the pulse-width and the pulse-period of the PWM signal. The PWM signal may be provided to the switching power core to control the switching of the switching power core.
    Type: Grant
    Filed: January 27, 2012
    Date of Patent: May 6, 2014
    Assignee: Draker, Inc.
    Inventor: Bertrand J. Williams
  • Publication number: 20130279410
    Abstract: Establishing a mesh network. A gateway in the mesh network may broadcast a wireless message to neighboring nodes of the gateway in the mesh network. The neighboring nodes may store first hop count information based on the wireless message received from the gateway. The neighboring nodes may each broadcast the wireless message to other neighboring nodes in the wireless mesh network. The other neighboring nodes may store second hop count information based on the received messages from the respective neighboring nodes. The second hop count information may indicate a greater hop count than the first hop count information. The first hop count information and the second hop count information may be used to establish routes from nodes to gateways in subsequent communications in the mesh network.
    Type: Application
    Filed: April 4, 2013
    Publication date: October 24, 2013
    Applicant: Draker, Inc.
    Inventors: Wilbur L. Dublin, III, Donald J. Davis, Thadeus N. Burgess
  • Publication number: 20130279409
    Abstract: Establishing a mesh network. A gateway in the mesh network may broadcast a wireless message to neighboring nodes of the gateway in the mesh network. The neighboring nodes may store first hop count information based on the wireless message received from the gateway. The neighboring nodes may each broadcast the wireless message to other neighboring nodes in the wireless mesh network. The other neighboring nodes may store second hop count information based on the received messages from the respective neighboring nodes. The second hop count information may indicate a greater hop count than the first hop count information. The first hop count information and the second hop count information may be used to establish routes from nodes to gateways in subsequent communications in the mesh network.
    Type: Application
    Filed: April 4, 2013
    Publication date: October 24, 2013
    Applicant: Draker, Inc.
    Inventors: Wilbur L. Dublin, III, Donald J. Davis, Thadeus N. Burgess