Patents by Inventor Lesley Chisenga

Lesley Chisenga has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20150280642
    Abstract: A solar photovoltaic sensing, control and monitoring system consisting of a sensing and control device that connects to the output of a solar module, collects the output voltage and current values, generates derivative values, such as cumulative energy, thereof and transmits the values to a monitoring device via a wired or wireless communication channel, and a monitoring device for receiving the values and transmitting instructions. The monitoring device may constitute a display and connect to a database or another device via a medium such as the internet. In some preferred embodiment, the sensing and control device includes an automatic switch or switches in series with the current carrying conductors connected to the solar module output. The switches disconnect the solar module output from the load. Furthermore, the sensing and control device may include an automatic switch in parallel to the current carrying conductors for bypassing the solar module output.
    Type: Application
    Filed: March 25, 2014
    Publication date: October 1, 2015
    Inventor: Lesley Chisenga
  • Publication number: 20140252859
    Abstract: We describe a photovoltaic (PV) power generation system comprising at least two PV panels and a power conditioning unit. The dc power outputs of the PV panels are connected in parallel to a dc power input of the power conditioning unit. The power conditioning unit comprises a dc-to-dc converter having an input coupled to the dc power input and an output coupled to a dc link of the unit, a dc-to-ac converter having an input coupled to the dc link and an ac mains power supply output, and an energy storage capacitor coupled to the dc link. The power conditioning unit is configured to perform maximum power point tracking (MPPT) responsive to a level of power flowing into the dc power input, and the level of power flowing into said dc power input is sensed at the dc link. In preferred implementations the energy storage capacitor is a non-electrolytic capacitor.
    Type: Application
    Filed: March 10, 2014
    Publication date: September 11, 2014
    Applicant: Enecsys Limited
    Inventors: Lesley Chisenga, Andrew John Matthews, Paul Randal Engle, JR.
  • Publication number: 20140191583
    Abstract: Some embodiments of the invention provide a method for balancing the power output to each phase of a set of micro-inverters. The method of some embodiments is performed by a gateway, which receives output messages from a plurality of micro-inverters. The gateway identifies the phase of each micro-inverter and calculates the output of the plurality of micro-inverters to each power line of a multi-phase system. The gateway then sends control signals to the micro-inverters to control the output of each micro-inverter to maintain a balanced aggregate power output to each phase of the power grid.
    Type: Application
    Filed: March 13, 2013
    Publication date: July 10, 2014
    Inventors: Lesley Chisenga, Aaron Jungreis, Paul Garrity
  • Patent number: 8674668
    Abstract: We describe a photovoltaic (PV) power generation system comprising at least two PV panels and a power conditioning unit. The dc power outputs of the PV panels are connected in parallel to a dc power input of the power conditioning unit. The power conditioning unit comprises a dc-to-dc converter having an input coupled to the dc power input and an output coupled to a dc link of the unit, a dc-to-ac converter having an input coupled to the dc link and an ac mains power supply output, and an energy storage capacitor coupled to the dc link. The power conditioning unit is configured to perform maximum power point tracking (MPPT) responsive to a level of power flowing into the dc power input, and the level of power flowing into said dc power input is sensed at the dc link. In preferred implementations the energy storage capacitor is a non-electrolytic capacitor.
    Type: Grant
    Filed: November 16, 2010
    Date of Patent: March 18, 2014
    Assignee: Enecsys Limited
    Inventors: Lesley Chisenga, Andrew John Matthews, Paul Randal Engle, Jr.
  • Publication number: 20130279210
    Abstract: We describe a power conditioning unit with maximum power point tracking (MPPT) for a dc power source, in particular a photovoltaic panel. A power injection control block has a sense input coupled to an energy storage capacitor on a dc link and controls a dc-to-ac converter to control the injected mains power. The power injection control block tracks the maximum power point by measuring a signal on the dc link which depends on the power drawn from the dc power source, and thus there is no need to measure the dc voltage and current from the dc source. In embodiments the signal is a ripple voltage level and the power injection control block controls an amplitude of an ac current output such that an amount of power transferred to the grid mains is dependent on an amplitude of a sinusoidal voltage component on the energy storage capacitor.
    Type: Application
    Filed: March 15, 2013
    Publication date: October 24, 2013
    Inventors: Lesley Chisenga, Gehan Anil Joseph Amaratunga, Cuauhtemoc Rodriguez
  • Publication number: 20130234518
    Abstract: 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.
    Type: Application
    Filed: February 22, 2013
    Publication date: September 12, 2013
    Applicant: Enecsys Limited
    Inventors: Asim Mumtaz, Lesley Chisenga, Gehan Anil Joseph Amaratunga
  • Patent number: 8405248
    Abstract: 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.
    Type: Grant
    Filed: June 3, 2010
    Date of Patent: March 26, 2013
    Assignee: Enecsys Limited
    Inventors: Asim Mumtaz, Lesley Chisenga, Gehan Anil Joseph Amaratunga
  • Patent number: 8405367
    Abstract: We describe a power conditioning unit with maximum power point tracking (MPPT) for a dc power source, in particular a photovoltaic panel. A power injection control block has a sense input coupled to an energy storage capacitor on a dc link and controls a dc-to-ac converter to control the injected mains power. The power injection control block tracks the maximum power point by measuring a signal on the dc link which depends on the power drawn from the dc power source, and thus there is no need to measure the dc voltage and current from the dc source. In embodiments the signal is a ripple voltage level and the power injection control block controls an amplitude of an ac current output such that an amount of power transferred to the grid mains is dependent on an amplitude of a sinusoidal voltage component on the energy storage capacitor.
    Type: Grant
    Filed: May 27, 2010
    Date of Patent: March 26, 2013
    Assignee: Enecsys Limited
    Inventors: Lesley Chisenga, Gehan Anil Joseph Amaratunga, Cuauhtemoc Rodriguez
  • Patent number: 8310101
    Abstract: The invention relates to a grid synchronizer for connecting an AC output of a power converter to the AC grid mains. In one aspect the invention provides a grid synchronizer comprising an inverter controller to control an AC output of the inverter, the controller including a receiver to receive grid data from a grid sensor location remote from said inverter. In another aspect we describe techniques for rapid removal of charge from a control terminal of a power switching device such as a MOSFET, IGBT or Thyristor using a particular driver circuit.
    Type: Grant
    Filed: December 19, 2008
    Date of Patent: November 13, 2012
    Assignee: Enecsys Limited
    Inventors: Gehan Anil Joseph Amaratunga, Lesley Chisenga, Andrabadu Viraj
  • Patent number: 8077437
    Abstract: We describe a semiconductor-on-insulator integrated circuit die comprising a substrate bearing a power conditioning circuit, the power conditioning circuit comprising at least two power devices, a lateral power device and a vertical power device. The power conditioning circuit comprises: a DC input to receive DC power, an AC output for connection to AC mains; a DC-to-DC converter having an input coupled to said DC input; a DC-to-AC converter having a DC input and an AC output to convert DC power to AC power for mains output; and a DC voltage regulator coupled between the output of said DC-to-DC converter and the input of said DC-to-AC converter to regulate said DC voltage input to said DC-to-AC converter. The regulator is configured to control an AC output current of said circuit by controlling said DC voltage input to the DC-to-AC converter.
    Type: Grant
    Filed: November 7, 2005
    Date of Patent: December 13, 2011
    Assignee: Enecsys Limited
    Inventors: Asim Mumtaz, Lesley Chisenga
  • Publication number: 20110298305
    Abstract: We describe a photovoltaic (PV) power generation system comprising at least two PV panels and a power conditioning unit. The dc power outputs of the PV panels are connected in parallel to a dc power input of the power conditioning unit. The power conditioning unit comprises a dc-to-dc converter having an input coupled to the dc power input and an output coupled to a dc link of the unit, a dc-to-ac converter having an input coupled to the dc link and an ac mains power supply output, and an energy storage capacitor coupled to the dc link. The power conditioning unit is configured to perform maximum power point tracking (MPPT) responsive to a level of power flowing into the dc power input, and the level of power flowing into said dc power input is sensed at the dc link. In preferred implementations the energy storage capacitor is a non-electrolytic capacitor.
    Type: Application
    Filed: November 16, 2010
    Publication date: December 8, 2011
    Inventors: Lesley CHISENGA, Andrew John MATTHEWS, Paul Randal ENGLE, JR.
  • Patent number: 8067855
    Abstract: 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.
    Type: Grant
    Filed: May 6, 2004
    Date of Patent: November 29, 2011
    Assignee: Enecsys Limited
    Inventors: Asim Mumtaz, Lesley Chisenga, Gehan Anil Joseph Amaratunga
  • Publication number: 20110049990
    Abstract: The invention relates to a grid synchroniser for connecting an AC output of a power converter to the AC grid mains. In one aspect the invention provides a grid synchroniser comprising an inverter controller to control an AC output of the inverter, the controller including a receiver to receive grid data from a grid sensor location remote from said inverter. In another aspect we describe techniques for rapid removal of charge from a control terminal of a power switching device such as a MOSFET, IGBT or Thyristor using a particular driver circuit.
    Type: Application
    Filed: December 19, 2008
    Publication date: March 3, 2011
    Applicant: ENECSYS LIMITED
    Inventors: Gehan Anil Joseph Amaratunga, Lesley Chisenga, Andrabadu Viraj
  • Publication number: 20100309692
    Abstract: We describe a power conditioning unit with maximum power point tracking (MPPT) for a dc power source, in particular a photovoltaic panel. A power injection control block has a sense input coupled to an energy storage capacitor on a dc link and controls a dc-to-ac converter to control the injected mains power. The power injection control block tracks the maximum power point by measuring a signal on the dc link which depends on the power drawn from the dc power source, and thus there is no need to measure the dc voltage and current from the dc source. In embodiments the signal is a ripple voltage level and the power injection control block controls an amplitude of an ac current output such that an amount of power transferred to the grid mains is dependent on an amplitude of a sinusoidal voltage component on the energy storage capacitor.
    Type: Application
    Filed: May 27, 2010
    Publication date: December 9, 2010
    Inventors: Lesley Chisenga, Gehan Anil Joseph Amaratunga, Cuauhtemoc Rodriguez
  • Publication number: 20100264736
    Abstract: 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.
    Type: Application
    Filed: June 3, 2010
    Publication date: October 21, 2010
    Inventors: Asim Mumtaz, Lesley Chisenga, Gehan Anil Joseph Amaratunga
  • Patent number: 7626834
    Abstract: A DC to AC power converter is disclosed. The power converter has four power-switching devices, two diodes, a step-up and isolation transformer, a capacitor-choke filter and a controller. Two power-switching devices located on the primary side of the transformer are switched to provide alternate cycles of an ac current to the primary side of the transformer, which magnetically couples the ac current to the secondary side of the transformer. Two power-switching devices on the secondary side of the transformer are switched to alternately allow the forward and return ac currents from the secondary side of the transformer in the output path to a load connected to the output of the DC to AC power converter.
    Type: Grant
    Filed: June 29, 2007
    Date of Patent: December 1, 2009
    Assignee: Enecsys Limited
    Inventors: Lesley Chisenga, Asim Mumtaz, Gehan Amil Joseph Amaratunga
  • Publication number: 20080266922
    Abstract: We describe a semiconductor-on-insulator integrated circuit die comprising a substrate bearing a power conditioning circuit, the power conditioning circuit comprising at least two power devices, a lateral power device and a vertical power device. The power conditioning circuit comprises: a DC input to receive DC power, an AC output for connection to AC mains; a DC-to-DC converter having an input coupled to said DC input; a DC-to-AC converter having a DC input and an AC output to convert DC power to AC power for mains output; and a DC voltage regulator coupled between, the output of said DC-to-DC converter and the input of said DC-to-AC converter to regulate said PC voltage input to said DC-to-AC converter. The regulator is configured to control an AC output current of said circuit by controlling said DC voltage input to the DC-to-AC converter.
    Type: Application
    Filed: November 7, 2005
    Publication date: October 30, 2008
    Inventors: Asim Mumtaz, Lesley Chisenga
  • Publication number: 20080055952
    Abstract: A DC to AC power converter is disclosed. The power converter comprises four power-switching devices, two diodes, a step-up and isolation transformer, a capacitor-choke filter and a controller. Two power-switching devices located on the primary side of the transformer are switched to provide alternate cycles of an ac current to the primary side of the transformer, which magnetically couples the ac current to the secondary side of the transformer. Two power-switching devices on the secondary side of the transformer are switched to alternately allow the forward and return ac currents from the secondary side of the transformer in the output path to a load connected to the output of the DC to AC power converter.
    Type: Application
    Filed: June 29, 2007
    Publication date: March 6, 2008
    Inventors: Lesley Chisenga, Asim Mumtaz, Gehan Amaratunga
  • Publication number: 20070133241
    Abstract: 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.
    Type: Application
    Filed: May 6, 2004
    Publication date: June 14, 2007
    Inventors: Asim Mumtaz, Lesley Chisenga, Gehan Anil Amaratunga