摘要:
A ballast with end∼of∼life ("EOL'') protection is presented in which the voltage across a lamp at EOL is controlled to prevent the lamp from overheating, while the voltage across the lamps not at EOL is maintained to allow normal operation of those lamps, and when a new lamp is added to the ballast the AC voltage across all lamps is controlled to allow ignition of the newly added lamp without cycling the power of the ballast.
摘要:
[Object] To provide a lighting device which enables a user of an illumination fixture to select any of a fluorescent lamp and a DC lighting light source as represented by a light emitting diode, and further realizes safe use. [Means for Settlement] A lighting device has first control means 11 adapted to output a driving signal to switching elements Q1 and Q2 which are used to drive a discharge lamp La at high frequency via a resonance part 4, and second control means 12 adapted to output a driving signal to a switching element Q3 of a voltage conversion circuit (i.e. DC/DC conversion part 5) which steps down an output of a DC power source circuit 1, and the lighting device includes an inductor (i.e. preheating transformer T1) having secondary windings n2 and n3 for use in supplying a preheating current to a filament of the discharge lamp La, and a rectifier DB for rectifying a voltage in an output end of at least one of the secondary windings n2 and n3 (i.e. secondary winding n2), wherein an output path of the voltage conversion circuit (i.e. DC/DC conversion part 5) is connected in parallel with an output path of the rectifier DB.
摘要:
The invention relates to a method for testing whether at least two gas discharge lamps (L1, L2) to be operated with an electronic ballast (V) are the same type. The coil voltage and the coil current of each hot coil (W1b, W2b) of each gas discharge lamp (L1, L2) is measured in relation to a first time point and the coil resistances (R1cold, R2cold) are calculated therefrom. The absolute differential resistance (IRdiff I) is then calculated from both coil resistances (R1cold, R2cold). This is compared to a higher and a lower reference value (Ref1, Ref2), said comparison providing an indication as to whether both of the gas discharge lamps (L1, L2) are the same type.
摘要:
An electronic ballast for driving a gas discharge lamp comprises an inverter circuit that operates in a partially self-oscillating manner. The inverter circuit comprises a push-pull converter having a main transformer having a primary winding for producing a high-frequency AC voltage, semiconductor switches electrically coupled to the primary winding of the main transformer for conducting current through the primary winding on an alternate basis, and gate drive circuits for controlling the semiconductor switches on a cycle-by-cycle basis. The drive circuits control (e.g., turn on) the semiconductor switches in response to first control signals derived from the main transformer, and control (e.g., turn off) the semiconductor switches in response to second control signals received from a control circuit. The control circuit controls the semiconductor switches in response to a peak value of an integral of an inverter current flowing through the inverter circuit.
摘要:
Conventional circuit arrangements for operating vacuum gas discharge lamps comprise an inductive element (LI1) playing a role both upon reaching the operating state of the lamp and in the preceding ignition of the gas discharge. Prior to ignition, the coils (W1 and W2) of the lamp (L) are heated up. A special heating circuit is provided for this purpose. According to the invention, an inductive element (LI2) is also located in the heating circuit, the element preferably being magnetically coupled to the first inductive element (LI1).
摘要:
A display apparatus and a backlight unit which control a plurality of lamps, and a display driving method are provided. The display apparatus includes a display, and a backlight unit which provides a backlight to the display. The backlight includes a plurality of lamps, and a lamp driver which adjusts a frequency of power supplied to the plurality of lamps until all of the plurality of lamps enter a running mode.
摘要:
Power line communication (PLC) systems 100 are presented for connecting dimming switches with electronic ballasts for driving compact fluorescent lamps and other applications using a power distribution network, including a transmitter 110 and a receiver 200 connected in a series circuit for transmission of multi-bit data, where the receiver has a load control circuit for selectively adjusting the receiver 200 loading and to sense current interruptions to provide a data output.
摘要:
A control circuit for use in a ballast (100) configured for powering a first lamp set and a second lamp set. The second lamp set is operated via a controller (122B) and a second lamp driver circuit (120B). The controller (122B) enables the second lamp driver circuit (120B) as a function of a monitored value corresponding to a current through a lamp of the second lamp set. The control circuit (170) includes first (172) and second input terminals (174) for selectively connecting to the power supply. The control circuit (170) reduces the monitored value as a function of a connection state of the first (172) and second input terminals (174) of the control circuit (170) to the power supply. Thus, the control circuit (170) causes the controller (122B) to selectively operate the second lamp driver circuit (120B) in order to energize the second lamp set in combination with the first lamp set.
摘要:
Vorrichtung (10.1) zum Ansteuern einer Leuchtstofflampe (11). Die Vorrichtung (10.1) umfasst eine Leistungselektronik (16) mit einer Heizendstufe (16.2) für das Zünden der Leuchtstofflampe (11) und mit einer Röhrenendstufe (16.1) für das Brennen der Leuchtstofflampe (11). Weiterhin ist eine digitale Steuerung (15) zur Ansteuerung der Leistungselektronik (16) vorgesehen, wobei die digitale Steuerung (15) analoge Steuersignale (Hin, Lin) bereitstellt, um die Leistungselektronik (16) zu beeinflussen.
摘要:
Die Erfindung betrifft eine Schaltungsanordnung (1) zum Betreiben einer Gasentladungslampe (19), mit einem Wechselrichter (6) zum Bereitstellen einer Versorgungswechselspannung (U V ), mit einer Steuereinrichtung (9) zum Ansteuern des Wechselrichters (6), die nach Erfülltsein eines vorbestimmten Vorheizkriteriums eine Vorheizphase einleitet und nach Erfülltsein eines vorbestimmten Zündkriteriums die Frequenz der Versorgungswechselspannung (U V ) auf eine Zündfrequenz einstellt, mit einem Resonanzkreis (12) mit einer Resonanzdrossel (13), deren erster Anschluss mit dem Wechselrichter (6) gekoppelt ist und deren zweiter Anschluss mit einem Resonanzpol (15) gekoppelt ist, und mit einem Resonanzkondensator (14), der zwischen dem Resonanzpol (15) und dem Bezugspotential (10) der Steuereinrichtung (9) gekoppelt ist, und mit einem Transformator (23), dessen Primärwicklung (24) mit dem Resonanzkondensator (14) in Reihe geschaltet und mit dem Bezugspotential (10) der Steuereinrichtung (9) direkt verbunden sowie mittels eines elektrischen Schalters (27) nach Erfülltsein des Zündkriteriums überbrückt wird. Die Erfindung betrifft außerdem ein entsprechendes Verfahren.