A lighting system waveform shaping circuit (WSC) includes a line voltage input, a line voltage output connectable to an input voltage port of a control unit, a neutral line input connectable to a neutral line of a voltage power source, and the WSC including an impedance matching network (IMN) configured to alter an input impedance of the lighting control circuit. In one embodiment, the IMN can include a resistor in series with the line voltage input, and an actively-controlled bypass switch in parallel with the resistor. In another embodiment, the IMN can include respective ferrite chokes surrounding the input and the output voltage lines, a capacitor between the line voltage input and the neutral line input, a capacitor between the neutral line input and a protected earth ground, and a resistor in series between the neutral line input and the lighting control unit neutral line input port.

A device (500) and method (600) control a dimming level of one or more lighting units (130) in response to a user interaction with a reference-free user interface (410), such as a rocker-type interface. A bidirectional triode thyristor (460) supplies an AC input voltage (110) to the lighting unit(s) when it is triggered. A triggering circuit (510) triggers the bidirectional triode thyristor. The triggering circuit includes a capacitor (554) and a variable resistance element (510) which sets a time constant during each half cycle of a period of the AC input voltage for charging the capacitor to a triggering voltage which triggers the bidirectional triode thyristor. The resistance of the variable resistance element is controlled in response to a dimming input signal from the reference-free user interface. The dimming input signal indicates only relative changes in the output level of the lighting unit(s) with respect to the present level.

A discharge lamp drive device includes a discharge lamp driver adapted to supply a drive current to a discharge lamp having a first electrode and a second electrode, 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. The control section is configured to select one drive pattern of the plurality of drive patterns based on machine learning, and execute the selected drive pattern. In a case in which a predetermined condition is fulfilled, the control section executes a predetermined drive pattern of the plurality of drive patterns without selecting and executing the drive pattern based on the machine learning.

A controller comprises a controllably conductive device adapted to be coupled in series electrical connection between an AC power source and a load control device. The controller also comprises a control circuit coupled to the controllably conductive device for rendering the controllably conductive device conductive each half-cycle of the AC power source to generate a phase-control voltage. The control circuit is operable to render the controllably conductive device conductive for a portion of each half-cycle of the AC power source. The control circuit is operable to transmit a digital message to the load control device for controlling the power delivered to the load by encoding digital information in timing edges of the phase-control voltage, where the phase-control voltage having at least one timing edge in each half-cycle of the AC power source when the control circuit is transmitting the digital message to the load control device.

The present invention discloses a system and method for active power factor correction and current regulation in led circuit. The system (100) used in the LED driver circuit performs active PFC and current regulation through the dynamic input current wave shaping by limiting peak currents. The dynamic wave 5 shaping scheme is realized through hardware and firmware and is used to strike an optimal balance between current accuracy, Power factor, THD and peak inductor currents. The system (100) is versatile enough to improve PF and current accuracy in LED circuits and indimmers circuits.

An electrical ballast includes an inverter circuit and a detection circuit. The inverter circuit is configured to receive a dc voltage and provide an output voltage to a lighting module. The detection circuit is electrically coupled to the inverter circuit and a voltage source, and configured to detect an ac voltage signal in the inverter circuit, and pull down the voltage source from a supply level to an under voltage locking level to shut down the inverter circuit on the condition that the ac voltage signal is greater than a threshold value, and restart the inverter circuit after a delay period.

An electrical ballast includes an inverter circuit and a detection circuit. The inverter circuit is configured to receive a dc voltage and provide an output voltage to a lighting module. The detection circuit is electrically coupled to the inverter circuit and a voltage source, and configured to detect an ac voltage signal in the inverter circuit, and pull down the voltage source from a supply level to an under voltage locking level to shut down the inverter circuit on the condition that the ac voltage signal is greater than a threshold value, and restart the inverter circuit after a delay period.

A lighting device includes a ferroresonant transformer that receives an alternating current (AC) power signal and outputs an output power signal. The lighting device further includes a rectifier coupled to the ferroresonant transformer. The rectifier rectifies the output power signal from the ferroresonant transformer and generates a rectified power signal. The lighting device also includes a dc-to-dc converter coupled to the rectifier, wherein the dc-to-dc converter receives the rectified power signal and generates a regulated power signal.

A discharge lamp lighting device includes: a storage unit that stores information; a lamp drive unit that supplies drive power to the discharge lamp; a voltage detection unit that detects the lamp voltage of the discharge lamp; and a control unit that, on the basis of the voltage detection value supplied from the voltage detection unit, stores in the storage unit error log information that indicates the operating state of the discharge lamp when change of the lamp voltage indicates a predetermined voltage characteristic.

A discharge lamp lighting device includes: a storage unit that stores information; a lamp drive unit that supplies drive power to the discharge lamp; a voltage detection unit that detects the lamp voltage of the discharge lamp; and a control unit that, on the basis of the voltage detection value supplied from the voltage detection unit, stores in the storage unit error log information that indicates the operating state of the discharge lamp when change of the lamp voltage indicates a predetermined voltage characteristic.