An embodiment of a system includes an RF signal source, a first electrode, a second electrode, and a cavity configured to receive an electrodeless bulb. The RF signal source is configured to generate an RF signal. The first electrode is configured to receive the RF signal and to convert the RF signal into electromagnetic energy that is radiated by the first electrode. The cavity is defined by first and second boundaries that are separated by a distance that is less than the wavelength of the RF signal so that the cavity is sub-resonant. The first electrode is physically positioned at the first boundary, and the second electrode is physically positioned at the second boundary. The first electrode, the second electrode, and the cavity form a structure that is configured to capacitively couple the electromagnetic energy into the electrodeless bulb when the electrodeless bulb is positioned within the cavity.

For the purpose of power factor correction, an inductance (21) is supplied with an input voltage (Vin), wherein a controllable switching means (24) that is coupled to the inductance (21) is actuated in order to selectively charge and discharge the inductance (21). A control device (14) for actuating the switching means (24) is designed such that it actuates the switching means (24) selectively on the basis of one of a plurality of modes of operation. In a first mode of operation, a switch-on time is stipulated for the switching means (24) on the basis of a minimum waiting time and on the basis of a voltage that drops across the switching means (24).

For the purpose of power factor correction, an inductance (21) is supplied with an input voltage (Vin), wherein a controllable switching means (24) that is coupled to the inductance (21) is actuated in order to selectively charge and discharge the inductance (21). A control device (14) for actuating the switching means (24) is designed such that it actuates the switching means (24) selectively on the basis of one of a plurality of modes of operation. In a first mode of operation, a switch-on time is stipulated for the switching means (24) on the basis of a minimum waiting time and on the basis of a voltage that drops across the switching means (24).

An RF fluorescent lamp comprising an electric ballast comprising an inverter circuit operating at a first frequency that provides the voltage and current with reference to local ground to a switching node connected to a first end of a winding of a power coupler, a timing circuit operating at a second frequency equal to or less than half the first frequency, and an enable circuit activated by the timing circuit that enables and disables the inverter circuit.

A system, method, and computer program product for optimizing the cooling of a UV bulb during a UV irradiation process is described. A power level in which to operate the UV bulb is received. In addition, a particular type of UV bulb being used in the UV irradiation process is received. Thereafter, at least one optimal UV cooling parameter that corresponds to the power level and the type of UV bulb is retrieved from a UV source parameters database. At least one control signal is then sent to a cooling device that is based on the retrieved optimal UV cooling parameter, and the control signal instructs the cooling device to cool the particular type of UV bulb according to the retrieved optimal UV cooling parameter during the UV irradiation process.

An emergency output circuit for starting LED lamp tubes with leakage protection includes a PWM pulse genera tor provided with a PWM chip. When a control terminal detects a power outage, a high level of voltage is instantly output to the PWM chip, and the PWM pulse generator outputs complementary drive PWM rectangular waves with a controllable dead time, which are boosted and filtered into a 250V DC voltage; then, positive and negative alternating square waves are formed through a full-bridge inverter circuit, and two pairs of MOS transistors are turned on alternately through complementary PWM control to generate an AC voltage UAB on an LED lamp tube; and finally, an AC rectangular wave slowly changing into a stable 135V AC output from a 250V DC output is obtained through a correction circuit to replace existing methods to turn on the LED tube, thus effectively simplifying the circuit.

A discharge lamp drive device includes a discharge lamp driver adapted to supply a drive current to a discharge lamp, a control section adapted to control the discharge lamp driver, and a storage section adapted to store a plurality of drive patterns of the drive current. Each of the drive patterns has a plurality of drive parameters. The plurality of drive patterns includes a first drive pattern and a second drive pattern different from each other in a value of at least one of the plurality of drive parameters. The control section is configured to execute the first drive pattern and the second drive pattern in accordance with at least one of accumulated lighting time of the discharge lamp and an individual of the discharge lamp in a case in which an inter-electrode voltage of the discharge lamp is at a predetermined voltage value.

A constant output current LED driver is disclosed. The driver is capable of operating with a wide range of input direct current (DC) voltage, and is configured with a full bridge inverter, an auxiliary circuit, and a voltage current converter. The full bridge inverter and auxiliary circuit collectively operate to provide a phase shift controller for the LED driver system. The LED driver operates under zero voltage switching (ZVS) for all switches in the LED driver circuit for all of the input voltage levels and for all of the output voltage levels. By maintaining ZVS in all conditions, the system can operate at very high frequency and be compact yet still achieve high power density. The resulting topology is applicable for a wide range of constant output current LED drivers. Switchable loads other than LEDs can also be driven.

An airfield runway lamp controller is described herein. One airfield runway lamp controller includes a current sense transformer configured to detect a failure of a light source of an airfield runway lamp, and an alternating current (AC) switch configured to shunt the light source of the airfield runway lamp upon the current sense transformer detecting a failure of the light source.

A sanitization apparatus includes an excimer lamp, a power converter configured to power the excimer lamp and a controller. The controller is configured to monitor an impedance of the excimer lamp and vary an output voltage waveform of the power converter based upon the impedance.