Abstract:
A circuit for providing electrical discharge machining power pulse on-off time control responsive to gap open circuit condition with controlled timing of pulse narrowing and return to normal pulse duration.
Abstract:
Some embodiments include a high voltage, high frequency switching circuit. In some embodiments, the high voltage, high frequency switching circuit includes a high voltage switching power supply that produces pulses having a voltage greater than 1 kV and with frequencies greater than 10 kHz; a transformer having a primary side and secondary side; an output electrically coupled with the secondary side of the transformer; and a primary sink electrically coupled with the primary side of the transformer and in parallel with the high voltage switching power supply, the primary sink comprising at least one resistor that discharges a load coupled with the output.
Abstract:
A light-emitting diode (LED)-based solid-state device comprises a color mixing mechanism to dynamically change the correlated color temperature (CCT) of a white light. With different lumen proportions for white phosphor-coated LEDs and integrated red and green LEDs, the light mixtures can be located in any one of eight CCT quadrangles. In practice, CCTs of a white-light can be tuned in a continuous manner. Because all the possible light mixtures on the chromaticity diagram correspond to a line segment that overlays the Planckian locus within the eight CCT tolerance quadrangles, the effect of LED intensity fluctuations that may put the mixture out of white light region is reduced. Also, because the two additional LEDs that mix with the white phosphor-coated LEDs contribute to the overall spectral power distribution (SPD) that substantially matches the SPD of standard illuminants, a CRI of 80 can be reached.
Abstract:
An electronic operating device for operating at least one discharge lamp may include an output network having at least one input connection and at least one output connection, wherein the at least one input connection of the output network is coupled to one of a plurality of voltage rails, and wherein the at least one output connection of the output network is coupled to one of a plurality of poles of a supply voltage.
Abstract:
In a discharge lamp lighting apparatus, in a starting sequence of a discharge lamp, while a frequency control circuit generates a inverter driving signal corresponding to resonance frequency of a resonant circuit, a power supply circuit outputs non-load open circuit voltage that is sufficient to maintain electric discharge, even when a boosting action accompanying a resonance phenomena disappears, and then a periodic drive circuit generates the inverter driving signal to gradually decrease frequency of the inverter from a frequency corresponding to the resonance frequency of the resonant circuit, until the frequency of the inverter reaches a first threshold frequency, and wherein when the frequency of the inverter reaches the first threshold frequency, while the periodic drive circuit generates the inverter driving signal so that the frequency of the inverter turns into a stable lighting frequency, the power supply circuit outputs current that is sufficient to maintain the electric discharge of the discharge lamp.
Abstract:
A high pressure discharge lamp lighting device in this invention comprises a converter, an inverter, an igniter, a controller, and a pulse voltage detection circuit. The converter outputs the direct current voltage. The inverter converts the direct current voltage into the lighting voltage which is alternating current voltage, and applies the lighting voltage to the high pressure discharge lamp through an output terminal. The igniter is configured to output the pulse voltage superimposed on the lighting voltage, whereby the starting voltage is applied to the high pressure discharge lamp. The controller is configured to control the igniter to allow the igniter to superimpose the pulse voltage on the lighting voltage. The pulse voltage detection circuit detects the starting voltage to output the detection signal. The starting voltage regulation circuit regulates the starting voltage to the desired voltage value of the voltage on the basis of the detection signal.
Abstract:
An apparatus and method thereof for igniting and operating a high intensity discharge (HID) lamp during an in service life, and powering down the lamp when an end-of-life (EOL) lamp condition is detected. The apparatus and method defines a series of thresholds of lamp voltage asymmetry, or rectification thresholds, and monitors the lamp rectification from ignition through normal operation. The detection scheme is masked off for a predetermined period of time when the lamp is initially started. Thereafter, the rectification threshold of the lamp voltage asymmetry is gradually reduced over time, until a defined minimum rectification threshold level is reached and maintained. The method continuously monitors the lamp voltage and records whenever the lamp voltage asymmetry is higher than the rectification threshold level at any lamp voltage cycle. An EOL lamp condition is determined to exist when a certain number of high asymmetrical cycles occurs in selected total number of lamp voltage cycles during a rolling measurement window.
Abstract:
An ignition circuit and method, as may be used for igniting a gas discharge lamp, are provided. The circuit includes a voltage multiplier circuit connected to receive a signal corresponding to a DC bus voltage level from a rectifier circuit. The voltage multiplier circuit includes first and second voltage storing circuits configured to each respectively store a voltage level corresponding to a first multiple of the DC bus voltage level (e.g., at least twice the DC bus voltage level). The voltage multiplier circuit further includes a peak voltage holding circuit connected to the first and second voltage storing circuits to accumulate a voltage level corresponding to a second multiple of the DC bus voltage level (e.g., at least four times the DC bus voltage level). The circuit further includes an ignition module having a transformer selectively connected by way of a switch to the voltage multiplier circuit through a primary winding to receive the voltage accumulated at the peak voltage holding circuit, and thereby generate an ignition pulse voltage applied to the lamp through a secondary winding of the transformer.
Abstract:
To provide a discharge lamp ignition device to light high-intensity discharge lamps in which, during alternating current ignition, the fluctuation of luminous flux on the reversal of polarity of the voltage impressed on the lamp is minimized and in which steady lighting characteristics of the discharge at startup are secured, a discharge lamp ignition device has a capacitor Ch connected to a transformer Th and an intermittent voltage impression arrangement Uj to drive voltage impression on the primary winding Ph, with the secondary winding Sh of the transformer Th constituted so that the voltage generated in the secondary winding Sh can be impressed overlapping the output voltage of an inverter Ui between the electrodes of the discharge lamp Ld by interposing it in the path connecting the output of the inverter Ui and the electrode for the main discharge of the discharge lamp Ld.
Abstract:
A connection wire 110 extends from an end of an induction coil 109, along a surface of a base portion 104b of a bobbin 104, which surface is located close to a luminous bulb 101. The connection wire 110 is separated from a sealing portion 118 of an inner tube 120 and an outertube 119.