801 results about "Electrical ballast" patented technology

A ballast circuit is disclosed for inductively providing power to a load. The ballast circuit includes an oscillator, a driver, a switching circuit, a resonant tank circuit and a current sensing circuit. The current sensing circuit provides a current feedback signal to the oscillator that is representative of the current in the resonant tank circuit. The current feedback signal drives the frequency of the ballast circuit causing the ballast circuit to seek resonance. The ballast circuit preferably includes a current limit circuit that is inductively coupled to the resonant tank circuit. The current limit circuit disables the ballast circuit when the current in the ballast circuit exceeds a predetermined threshold or falls outside a predetermined range.

The present invention is directed to a fluorescent light fixture assembly including a ballast and a novel lighting element that includes an array of LEDs and at least one converter module that enables the existing ballast providing an AC power input to supply DC power to the LED array. The lighting element includes a body that contains the LED array and the converter modules and shares the configuration of the lighting element that is to be retrofitted. The lighting element receives power from the pre-existing ballast, wherein the converter module provides a constant current source to power the LED array. Thus, the lighting element, including the converter module, replaces the conventional fluorescent light tube in a cost-effective retrofit manner with the existing ballast.

This invention relates to a solar energy high pressure Na-lamp controller based on a single stage inverter characterizing in applying a sectional charge control and a frequency conversion output control, in which, the hardware includes a singlechip control circuit, a single-stage total bridge inversion circuit, a storage battery charge circuit, a high frequency electronic ballast circuit, a solar energy cell, storage batteries and luminaries, the controller is charged by MPPT to increase the system efficiency and applies frequency conversion output to control the current of the lamp, besides, a design of machine-card separation is applied to the controller on the structure to meet the needs of different luminaries and lamination, the control structure is integrated in a control card suitable for software upgrading.

The invention discloses an LED (light-emitting diode) tube and a drive circuit thereof.The drive circuit comprises an input unit, a rectification filter unit and an LED constant current drive unit, and further comprises a high frequency detection unit and a control unit. The LED tube disclosed by the invention includes the drive circuit of the LED tube and an LED light source plate, and has simple structure and convenience in use when the LED fluorescent lamp is exchanged with a traditional electronic ballast fluorescent lamp and an inductive ballast fluorescent lamp, without needs of line adjustment and component disassembly.

An LED tube lamp having an LED unit is disclosed. The LED tube lamp includes a control circuit that selectively determines whether to perform a first mode or a second mode of lighting operation according to a state of a property of an external driving signal and a switching circuit coupled to the control circuit and the LED unit. When the control circuit determines to perform the first mode of lighting operation, the control circuit controls the second circuit in a manner such that the switching circuit maintains its on state to allow continual current to flow through the LED unit, until the external driving signal is disconnected from the LED tube lamp, and when the control circuit determines to perform the second mode of lighting operation, the control circuit controls the switching circuit in a manner to regulate the continuity of current to flow through the LED unit by alternately turning on and off the switching circuit.

There is provided lamp ballast impedance controlled electronic lamp circuit, powered by a lamp ballast, for controlling a set of light emitting devices and being, comprising at least one connector, for connecting to the lamp ballast; and for receiving an AC signal; at least one filament control, associated with one of the at least one connector; a circuit for transforming the AC signal to a DC signal; a power convertor circuit; for receiving the DC signal and for processing the DC signal to provide a signal to power to the set of light emitting devices; a control and monitoring circuit; wherein the control and monitoring circuit monitors the DC signal and controls the impedance of either the at least one filament control or the power convertor circuit to control the set of light emitting devices.

In one example hydraulic ballast of the invention there is provided an input port and an output port through which a prespecified output flow rate is required. There is provided between the input and output ports a ballasting array of columns having a cross-sectional column extent, W, a column pitch, P, and an array length, L, selected based on the required output flow rate, to produce a prespecified pressure drop that enforces the required output flow rate.

A lamp control circuit is described, containing a power factor corrector, coupled to it a digitally controlled ballast, having power devices. The digitally controlled ballast is capable of powering a lamp. The ballast is controlled by a current feedback loop, coupled between the power devices and the digitally controlled ballast, and a voltage feedback loop, coupled between the lamp and the digitally controlled ballast. Further, a method of operating a lamp-control circuit is presented, the circuit containing a digital controller, an output stage, a current feedback loop, and a voltage feedback loop. In operation the digital controller receives a current feedback signal or a voltage feedback signal from the output stage and the lamp. In response to the received signal the digital controller generates a digital control signal and powers a lamp through the output stage according to the generated digital control signal.

A fluorescent lamp assembly includes a fixture which supports at least one fluorescent lamp. A ballast is mounted to the fixture for controlling a supply of electrical current to the fluorescent lamp. A thermal transfer material is interposed between the ballast and a portion of the fixture whereby heat is transferred between the ballast and the fixture.

A light performance monitoring device and optionally integrated controller includes a monitor module that directly monitors energy usage of at least one energy load to generate at least one measurement of energy usage; a storage module stores a series of baseline values of energy usage of the energy load, a comparator module compares energy measurements made at predetermined intervals with the baseline values, and a notification module notifies a designated recipient that there is a deviation from the baseline values consistent with a burned out or non-operational light fixture, including but not limited to light bulbs or ballast devices. A control module optionally integrated with the light performance monitoring device can be operatively coupled to the monitor module to control energy usage by the at least one energy load via a data link in a pre-determined manner that is based on the at least one measurement of energy usage.

The invention discloses a switching circuit which is compatible with fluorescent lamp ballast. The switching circuit comprises a rectifying module, a switching module and an LED driving module. The output end of the rectifying module is connected with the input end of the switching module. The output end of the switching module is connected with the input end of the LED driving module. The rectifying module is used for converting an alternating current of an external power supply into a direct current, and then outputting the direct current. When a voltage value output by the rectifying module is lower than a preset threshold value, impedance switching is carried out on the switching module, and equivalent impedance of the switching circuit is increased. The invention further discloses an LED lamp which is compatible with the fluorescent lamp ballast. The LED lamp comprises an LED module and the switching circuit which is compatible with the fluorescent lamp ballast. The output end of the LED driving module is connected with the LED module. The LED lamp which adopts the switching circuit can be fully compatible with direct power connection and one-with-one-type and one-with-more-type ballast of a current fluorescent lamp, and has the advantages of being simple and efficient in design, convenient to replace, and low in cost.

An electronic ballast for driving a gas discharge lamp avoids mercury pumping in the lamp by adaptively changing an operating frequency of an inverter of the ballast when operating near high-end. The inverter of the ballast generates a high-frequency AC voltage, which is characterized by the operating frequency and an operating duty cycle. The ballast also comprises a resonant tank for coupling the high-frequency AC voltage to the lamp to generate a present lamp current through the lamp, and a current sense circuit for determining the magnitude of the present lamp current. A hybrid analog/digital control circuit controls both the operating frequency and the operating duty cycle of the inverter with closed-loop techniques. The control circuit adjusts the duty cycle of the inverter in response to a target lamp current and the present lamp current. To avoid mercury pumping, the control circuit attempts to maximize the duty cycle of the inverter when operating at high-end. Specifically, the control circuit adjusts the operating frequency of the inverter in response to the target lamp current signal, the duty cycle of the inverter, and a target duty cycle in order to drive the operating duty cycle toward the target duty cycle.

This compact fluorescent lamp comprises a discharge tube arrangement with at least one discharge tube. The tube is formed of glass, encloses a discharge volume filled with a discharge gas and has a fluorescent phosphor coating disposed on the inner surface of the tube. The tube forms a continuous arc path and the tube is provided with electrodes disposed at each end of the arc path. The lamp also comprises a ballast circuit connected to the electrodes for controlling the current in the tube and a lamp base for connecting said lamp to a power supply through a socket. The lamp is enclosed in an outer envelope comprising a substantially spherical portion enclosing the tube arrangement and an elongated end portion enclosing the ballast circuit. The end portion of the outer envelope is closed and sealed by a sealing means of the same material as the material of the outer envelope. The sealing means is connected to the envelope in a hermetically sealing way. A method for manufacturing a compact fluorescent lamp as described above is also disclosed. In the method, an outer envelope with an open end on the base side is provided. The open end of the envelope is closed and sealed with a sealing means to provide a hermetic seal. The envelope is separated by cutting along a circumferential line into an upper part and a lower part. The ballast circuit is introduced into the lower part and respective connection points of the ballast circuit are connected to power supply lead-out wires. The discharge tube arrangement is connected to respective connection points of the ballast circuit by lead-in wires. The lead-in wires and the lead-out wires are short and need not be insulated. The ballast circuit and the discharge tube arrangement are held and supported in the outer envelope by the connecting wires and fixing means.

An LED tube lamp is disclosed. The LED tube lamp includes an LED module for emitting light, the LED module comprising an LED unit comprising an LED; a rectifying circuit for rectifying an external driving signal to produce a rectified signal; and a mode determination circuit configured to detect a state of a property of the rectified signal, for selectively determining on performing a first mode or a second mode of lighting according to the state of the property of the rectified signal; wherein when the LED tube lamp performs the first mode of lighting, the mode determination circuit allows continual current to flow through the LED unit until the external driving signal is disconnected from the LED tube lamp; and when the LED tube lamp performs the second mode of lighting, the mode determination circuit regulates the continuity of current to flow through the LED unit.

A programmable waveform ballast has a power supply and a waveform generator. The power supply provides, from a power source, a variable power to a discharge lamp. The waveform generator is coupled to the power supply and is programmable to produce a plurality of waveforms. The waveform generator controls the power supply to apply the variable power to the discharge lamp in accordance with a programmed waveform.

A power source module for a LED lamp includes a filament-simulating circuit, a current limiting circuit, a rectifier, a filter, and a discharging circuit electrically connected to each other and a LED in the LED lamp. The filament-simulating circuit simulates a filament before the LED to pass through the pre-heating process of the electrical ballast in a fluorescent lamp base. The current limiting circuit, the rectifier, and the filter limit, rectify and filter the current from an external power source in the fluorescent lamp base to output a high frequency, direct current to drive the LED. The discharging circuit discharges the energy after turning the power switch off to prevent the LED lamp from flicker. Therefore, the power source module enables the LED lamp to be installed on the traditional fluorescent lamp base without modifying the circuit in the base.

A ballast, or power supply circuit, for gas discharge lamps of the type using IC control based gate-drive circuitry for controlling a pair of serially connected switches of a d.c.-a.c. inverter. More particularly, the invention relates to a ballast having a resonant feedback circuit drawing continuous input current from a wide range of source voltages to satisfy requirements of phase control dimmers. Even more particularly, the invention relates to a universal platform for phase dimming discharge lighting using the Ballast and a discharge Lamp with a phase dimming circuit.

An integrated circuit controls a power converter that includes single stage buck-boost converter and a switching full bridge that may be used to drive an HID lamp. The single stage buck-boost converter reduces the complexity and parts count of the power converter, or electronic ballast, while permitting PFC and DC bus voltage regulation under control of the integrated circuit to maintain constant power on the HID lamp. The integrated circuit simplifies the design of power converters and electronic ballasts in particular, while reducing part count, complexity and cost in conjunction with the single stage buck-boost converter and the full bridge switching circuit.