Patents by Inventor Dragan Veskovic

Dragan Veskovic 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).

  • Patent number: 8629624
    Abstract: A load control device, such as an electronic ballast, for controlling the power delivered from an AC power source to an electrical load, such as one or more fluorescent lamps, comprises a power converter having an inductor and a power switching device coupled to the inductor, a load control circuit adapted to be coupled to the electrical load, and a control circuit operable to calculate an average input power of the load control device. The control circuit may be operable to calculate a cumulative output power of the power converter while the ballast is preheating filaments of the lamps, and to subsequently determine a fault condition in the lamps in response to the calculated cumulative output power of the power converter. Further, the control circuit may be operable to transmit a digital message including the calculated average input power of the load control device.
    Type: Grant
    Filed: August 18, 2011
    Date of Patent: January 14, 2014
    Assignee: Lutron Electronics Co., Inc.
    Inventors: Venkatesh Chitta, Jonathan Robert Quayle, Alexander J. Rovnan, Mark S. Taipale, Dragan Veskovic
  • Publication number: 20140009085
    Abstract: A load control device for controlling the intensity of a light source (e.g., a light-emitting diode light source) reduces visible flickering in the light source when a target intensity of the light source is dynamically changing. The load control device includes a load regulation circuit operable to conduct a load current through the electrical load and to control the amount of power delivered to the electrical load. The load control device also includes a controller for adjusting the average magnitude of the load current to a target current. The controller pulse-width modulates the magnitude of the load current between a first current less than the target current and a second current greater than the target current. When the target current is dynamically changing, the controller is operable to adjust to the average magnitude of the load current towards the sum of the target current and a supplemental signal.
    Type: Application
    Filed: July 5, 2013
    Publication date: January 9, 2014
    Inventor: Dragan Veskovic
  • Publication number: 20140009084
    Abstract: A load control device for controlling the amount of power delivered to an electrical load (e.g, an LED light source) comprises an isolated forward converter comprising a transformer, a controller, and a current sense circuit operable to receive a sense voltage representative of a primary current conducting through to a primary winding of the transformer. The primary winding is coupled in series with a semiconductor switch, while a secondary winding is adapted to be operatively coupled to the load. The forward converter comprises a sense resistor coupled in series with the primary winding for producing the sense voltage that is representative of the primary current. The current sense circuit receives the sense voltage and averages the sense voltage when the semiconductor switch is conductive, so as to generate a load current control signal that is representative of a real component of a load current conducted through the load.
    Type: Application
    Filed: March 15, 2013
    Publication date: January 9, 2014
    Applicant: LUTRON ELECTRONICS CO., INC.
    Inventor: Dragan Veskovic
  • Patent number: 8593076
    Abstract: An electronic ballast for driving a gas discharge lamp includes a power converter for generating a DC bus voltage, where the bus voltage is controlled to different magnitudes during different operating modes of the ballast. The ballast comprises a control circuit that is coupled to the power converter for adjusting the magnitude of the bus voltage to a first magnitude when the lamp is off, to a second magnitude when preheating filaments of the lamp, and to a third magnitude when the lamp is on. The control circuit is also operable to preemptively adjust the magnitude of the bus voltage prior to changing modes of operation. For example, when turning the load on, the control circuit first adjusts a power-conversion-drive level of the power converter to begin adjusting the magnitude of the bus voltage towards a predetermined magnitude, and then waits for a predetermined time period before attempting to turn the load on.
    Type: Grant
    Filed: August 18, 2011
    Date of Patent: November 26, 2013
    Assignee: Lutron Electronics Co., Inc.
    Inventor: Dragan Veskovic
  • Publication number: 20130063047
    Abstract: An LED driver for controlling the intensity of an LED light source includes a power converter circuit for generating a DC bus voltage, an LED drive circuit for receiving the bus voltage and controlling a load current through, and thus the intensity of, the LED light source, and a controller operatively coupled to the power converter circuit and the LED drive circuit. The LED drive circuit comprises a controllable-impedance circuit adapted to be coupled in series with the LED light source. The controller adjusts the magnitude of the bus voltage to a target bus voltage and generates a drive signal for controlling the controllable-impedance circuit. To adjust the intensity of the LED light source, the controller controls both the magnitude of the load current and the magnitude of the regulator voltage. The controller controls the magnitude of the regulator voltage by simultaneously maintaining the magnitude of the drive signal constant and adjusting the target bus voltage.
    Type: Application
    Filed: March 9, 2012
    Publication date: March 14, 2013
    Applicant: LUTRON ELECTRONICS CO., INC.
    Inventor: Dragan Veskovic
  • Patent number: 8368307
    Abstract: The invention regards a system and method for using a handheld programming device to configure a lighting control system wirelessly. In one embodiment, at least one device configured with a processing section is installed in the lighting control system. A communications receiver that is operable to receive a signal from the handheld programming device is also installed in the lighting control system, wherein the signal includes an instruction for configuring the lighting control system. Further, the signal is wirelessly sent from the handheld programming device to the communications receiver, and the instruction is transmitted from the communications receiver to a device in the system. The instruction functions to configure the lighting control system.
    Type: Grant
    Filed: October 29, 2010
    Date of Patent: February 5, 2013
    Assignee: Lutron Electronics Co., Inc.
    Inventors: Audwin W. Cash, Christopher J. Rigatti, Dragan Veskovic
  • Patent number: 8345400
    Abstract: A surge suppression circuit for a load control device allows the load control device to pass hipot testing, while providing improved protection of the load control device during surge events. The load control device comprises a load control circuit and a filter circuit for preventing noise generated by the load control circuit from being provided to an AC power source. The surge suppression circuit comprises a clamping device adapted to be electrically coupled across the AC power source, and first and second spark gaps coupled across the filter circuit for limiting the magnitude of the voltage generated by inductive components of the filter circuit. The filter circuit may comprise a common-mode choke, and two series-connected capacitor having their junction connected to earth ground. Alternatively, the filter circuit may additionally comprise a differential-mode choke.
    Type: Grant
    Filed: August 17, 2010
    Date of Patent: January 1, 2013
    Assignee: Lutron Electronics Co., Inc.
    Inventor: Dragan Veskovic
  • Patent number: 8228163
    Abstract: The invention regards a system and method for using a handheld programming device to configure a lighting control system wirelessly. In one embodiment, at least one device configured with a processing section is installed in the lighting control system. A communications receiver that is operable to receive a signal from the handheld programming device is also installed in the lighting control system, wherein the signal includes an instruction for configuring the lighting control system. Further, the signal is wirelessly sent from the handheld programming device to the communications receiver, and the instruction is transmitted from the communications receiver to a device in the system. The instruction functions to configure the lighting control system.
    Type: Grant
    Filed: November 30, 2007
    Date of Patent: July 24, 2012
    Assignee: Lutron Electronics Co., Inc.
    Inventors: Audwin W. Cash, Rishi Raj Kumar, Christopher J. Rigatti, Dragan Veskovic, John C. Hewson
  • Patent number: 8197093
    Abstract: A method of controlling a light level in a space of a building, the method comprising the steps of measuring the light level in the space; automatically adjusting the light level in the space towards a control setpoint; receiving an input to manually override the light level in the space to an override light level; adjusting the light level in the space to the override light level; temporarily adjusting the control setpoint from a default setpoint to a temporary setpoint in response to the manual override of the light level, the temporary setpoint representative of the override light level; subsequently adjusting the control setpoint from the temporary setpoint back to the default setpoint; and adjusting the default setpoint in response to repeated manual overrides of the light level that result in repeated adjustments of the control setpoint.
    Type: Grant
    Filed: May 5, 2011
    Date of Patent: June 12, 2012
    Assignee: Lutron Electronics Co., Inc.
    Inventor: Dragan Veskovic
  • Patent number: 8125315
    Abstract: A processing circuit for providing electronic photosensor information over a communication link. The processing circuit comprises a photosensor input circuit adapted to be directly coupled to a photosensor for receiving the electronic photosensor information from the photosensor. Further, a communication port is provided that allows for transmitting and receiving messages over the communication link. Moreover, a processor is provided that is coupled to the photosensor input circuit and the communication port. The processor determines whether the processor is operating in a default configuration, and broadcasts the electronic photosensor information on the communication link if the processor is operating in the default configuration.
    Type: Grant
    Filed: March 31, 2009
    Date of Patent: February 28, 2012
    Assignee: Lutron Electronics Co., Inc.
    Inventors: Dragan Veskovic, Robert Anselmo, Audwin W. Cash, Matthew A. Skvoretz
  • Publication number: 20120043900
    Abstract: A load control device, such as an electronic ballast, for controlling the power delivered from an AC power source to an electrical load, such as one or more fluorescent lamps, comprises a power converter having an inductor and a power switching device coupled to the inductor, a load control circuit adapted to be coupled to the electrical load, and a control circuit operable to calculate an average input power of the load control device. The control circuit may be operable to calculate a cumulative output power of the power converter while the ballast is preheating filaments of the lamps, and to subsequently determine a fault condition in the lamps in response to the calculated cumulative output power of the power converter. Further, the control circuit may be operable to transmit a digital message including the calculated average input power of the load control device.
    Type: Application
    Filed: August 18, 2011
    Publication date: February 23, 2012
    Applicant: LUTRON ELECTRONICS CO., INC.
    Inventors: Venkatesh Chitta, Jonathan Robert Quayle, Alexander J. Rovnan, Mark S. Taipale, Dragan Veskovic
  • Publication number: 20120044599
    Abstract: A surge suppression circuit for a load control device allows the load control device to pass hipot testing, while providing improved protection of the load control device during surge events. The load control device comprises a load control circuit and a filter circuit for preventing noise generated by the load control circuit from being provided to an AC power source. The surge suppression circuit comprises a clamping device adapted to be electrically coupled across the AC power source, and first and second spark gaps coupled across the filter circuit for limiting the magnitude of the voltage generated by inductive components of the filter circuit. The filter circuit may comprise a common-mode choke, and two series-connected capacitor having their junction connected to earth ground. Alternatively, the filter circuit may additionally comprise a differential-mode choke.
    Type: Application
    Filed: August 17, 2010
    Publication date: February 23, 2012
    Applicant: LUTRON ELECTRONICS CO., INC.
    Inventor: Dragan Veskovic
  • Publication number: 20120043905
    Abstract: An electronic ballast having an inverter circuit for driving a gas discharge lamp prevents allows some hard switching to occur in the inverter circuit in order to ensure adequate ballasting impedance to provide stable operation of the lamp, but not enough hard switching to generate excessive power loss in the inverter circuit. The inverter circuit comprises two switching devices that are coupled in series between a DC bus voltage and circuit common and are rendered conductive on a complementary basis, such that a high-frequency output voltage is generated at the junction of the switching devices. When the intensity of the lamp is at or near a low-end intensity, an operating frequency of the high-frequency output voltage is controlled to a low-end frequency that is low enough to ensure stable operation of the lamp and to allow some hard switching to occur in the switching devices, but high enough to prevent excessive power loss due to the hard switching in the switching devices.
    Type: Application
    Filed: August 16, 2011
    Publication date: February 23, 2012
    Applicant: LUTRON ELECTRONICS CO., INC.
    Inventors: Graham L. Christensen, Rebecca A. Merola, Thomas M. Shearer, Dragan Veskovic
  • Publication number: 20120043899
    Abstract: An electronic ballast for driving a gas discharge lamp includes a power converter for generating a DC bus voltage, where the bus voltage is controlled to different magnitudes during different operating modes of the ballast. The ballast comprises a control circuit that is coupled to the power converter for adjusting the magnitude of the bus voltage to a first magnitude when the lamp is off, to a second magnitude when preheating filaments of the lamp, and to a third magnitude when the lamp is on. The control circuit is also operable to preemptively adjust the magnitude of the bus voltage prior to changing modes of operation. For example, when turning the load on, the control circuit first adjusts a power-conversion-drive level of the power converter to begin adjusting the magnitude of the bus voltage towards a predetermined magnitude, and then waits for a predetermined time period before attempting to turn the load on.
    Type: Application
    Filed: August 18, 2011
    Publication date: February 23, 2012
    Applicant: LUTRON ELECTRONICS CO., INC.
    Inventor: Dragan Veskovic
  • Publication number: 20110254453
    Abstract: A method of controlling a light level in a space of a building, the method comprising the steps of measuring the light level in the space; automatically adjusting the light level in the space towards a control setpoint; receiving an input to manually override the light level in the space to an override light level; adjusting the light level in the space to the override light level; temporarily adjusting the control setpoint from a default setpoint to a temporary setpoint in response to the manual override of the light level, the temporary setpoint representative of the override light level; subsequently adjusting the control setpoint from the temporary setpoint back to the default setpoint; and adjusting the default setpoint in response to repeated manual overrides of the light level that result in repeated adjustments of the control setpoint.
    Type: Application
    Filed: May 5, 2011
    Publication date: October 20, 2011
    Inventor: Dragan Veskovic
  • Patent number: 8035529
    Abstract: A ballast for use in a multi-ballast lighting system wherein the ballasts are coupled together by a digital communication network. The ballast comprises a power circuit portion for providing an electrical current to power a lamp. The ballast further includes a sensor input circuit for receiving at least one sensor input from a sensor device, a processor receiving an input from the sensor input circuit and providing control signals to control the operation of the ballast, and a communication port coupled to the processor and to the communication network for exchanging data. The ballast processor is operative to receive a serial data that has a portion defining whether the message is in a first or a second format, the first format comprising a DALI standard format and the second format comprising a format providing extended functionality. The ballast processor is capable of processing messages in either the first or second formats.
    Type: Grant
    Filed: March 26, 2008
    Date of Patent: October 11, 2011
    Assignee: Lutron Electronics Co., Inc.
    Inventors: Dragan Veskovic, Robert Anselmo, Audwin W. Cash, Matthew A. Skvoretz
  • Publication number: 20110241561
    Abstract: An electronic ballast circuit for driving a gas discharge lamp is operable to control the lamp to avoid flicking and flashing of the intensity of the lamp during low temperature conditions. The ballast circuit includes an inverter circuit for receiving a DC bus voltage and for generating a high-frequency output voltage, a resonant tank circuit for receiving the high-frequency output voltage and generating a sinusoidal voltage for driving said lamp, and a control circuit operatively coupled to the inverter circuit for adjusting an intensity of the lamp between a minimum intensity and a maximum intensity. The control circuit receives a control signal representative of a lamp temperature of the lamp, and increases the minimum intensity of the lamp if the lamp temperature of the lamp drops below a cold temperature threshold. In addition, the ballast circuit may also include a temperature sensing circuit operable to generate the control signal representative of the lamp temperature of the lamp.
    Type: Application
    Filed: November 30, 2010
    Publication date: October 6, 2011
    Applicant: LUTRON ELECTRONICS CO., INC.
    Inventors: Venkatesh Chitta, Mehmet Ozbek, Jonathan Robert Quayle, Mark S. Taipale, Dragan Veskovic
  • Patent number: 7983012
    Abstract: A communication circuit for an electronic dimming ballast provides high-voltage miswire protection and improved rise and fall times of a transmitted digital signal. The electronic dimming ballast comprises a control circuit, which is coupled to a digital communication link, for example, a DALI communication link, via the communication circuit. The communication circuit comprises a receiving circuit for detecting when the digital ballast communication link is shorted and for providing a received digital message to the control circuit. The communication circuit also comprises a transmitting circuit for shorting the communication link in response to the control circuit. The communication circuit also includes a high-voltage fault protection circuit for protecting the circuitry of the communication circuit if the communication circuit high-voltage mains voltages. The communication circuit is operable to reliably transmit digital messages having improved rise and fall times.
    Type: Grant
    Filed: June 15, 2010
    Date of Patent: July 19, 2011
    Assignee: Lutron Electronics Co., Inc.
    Inventors: Venkatesh Chitta, Elik Dvorkin, Dragan Veskovic
  • Patent number: 7963675
    Abstract: A system for reducing sun glare through an opening into a space, the system comprising an electrically controllable window treatment operable to alter the amount of daylight entering the space through the opening; a first sensor mounted within the space and characterized by a sensor gain, the first sensor operable to sense a level of illumination in the space; and a control system operable: to compare the sensed illumination level in the space to a dead-band having upper and lower thresholds; to adjust during a time period when glare from the sun can occur through the opening at least one of: (a) the upper threshold of the dead-band, (b) the lower threshold of the dead-band, and (c) the sensor gain of the first sensor; and to adjust the window treatment in response to the sensed level of illumination to reduce the sun glare.
    Type: Grant
    Filed: August 14, 2009
    Date of Patent: June 21, 2011
    Inventor: Dragan Veskovic
  • Patent number: 7950827
    Abstract: A system for reducing sun glare through an opening into a space, the system comprising an electrically controllable window treatment operable to alter the amount of daylight entering the space through the opening; a first sensor mounted within the space and characterized by a sensor gain, the first sensor operable to sense a level of illumination in the space; and a control system operable: to compare the sensed illumination level in the space to a dead-band having upper and lower thresholds; to adjust during a time period when glare from the sun can occur through the opening at least one of: (a) the upper threshold of the dead-band, (b) the lower threshold of the dead-band, and (c) the sensor gain of the first sensor; and to adjust the window treatment in response to the sensed level of illumination to reduce the sun glare.
    Type: Grant
    Filed: August 14, 2009
    Date of Patent: May 31, 2011
    Assignee: Lutron Electronics Co., Inc.
    Inventor: Dragan Veskovic