Assessment of the effect of a Pulsed Power Supply on HgTℓI Lamp: Experimental Investigation of Energy Efficiency Lighting System

Assessment of the effect of a Pulsed Power Supply on HgTℓI Lamp: Experimental Investigation of Energy Efficiency Lighting System
The objective of this work is to study the influence of a pulsed power supply on the energy efficiency of high-intensity discharge lamps in comparison with a pseudocontinuous ballast. The results presented in this paper concern the dynamic behaviour of discharges in mercury vapour doped with thallium iodide. The acquisition of the arc current, arc voltage and spectral radiation enables us to investigate the influence of the pulsed power supply on the electrical characteristics of the lamp such as the behaviour of the lamp conductance and spectral radiance. The analysis of the 577nm mercury line’s response to the current pulse excitation allowed us to identify several phases. Good agreement has been found between simulation and experimental results. ...

تم النشر في: 2020-06-08 14:53:50

Behaviour of a high-intensity discharge lamp fed by a high-frequency dimmable electronic ballast

Behaviour of a high-intensity discharge lamp fed by a high-frequency dimmable electronic ballast
The main advantages of high-frequency electronic ballasts for high-intensity discharge lamps are high luminous efficacy, small size, lightweight and longer lifetime. This is why high-intensity discharge lamps operating at high frequency are widely used. This paper proposes an approach for designing resonant circuit electronic ballasts controlled by frequency variation for high-intensity discharge lamps. The proposed technique including an AC/DC rectifier, a power factor correction circuit and a DC/AC half bridge inverter. These electronic ballasts offer a wide range of dimming controls and can avoid acoustic resonance. However, under dimming, the electric and photometric characteristics of the lamp change. In order to study these effects under the process of dimming, this work studies the lamp properties by varying both lamp power and operating frequency. ...

تم النشر في: 2020-06-08 14:49:58

Diffusive representation modelling thermal and overvoltage for permanent

Diffusive representation modelling thermal and overvoltage for permanent
Abstract: Life of electric machines is very sensitive to temperature increases especially due to the fragility of their windings as well as to the overvoltage at the motor’s terminals. Therefore, it is necessary to find the temperature in the most sensitive areas of the machine. It has been known for a long time that temperature rise is caused by the losses in the machine; thus, various models have been proposed. It has also been shown that the permanent magnet synchronous motor fed by a voltage inverter overheats more than the one supplied by a sinusoidal voltage. Indeed the permanent magnet synchronous motor fed by a voltage inverter deserves special attention. In this paper a new technique based on diffusive representation is used to develop two coupled mathematical models; one for thermal variation in some of the most delicate places of winding and another one for the overvoltage at the motor’s terminals. The obtained simulations and experimental results show clearly the validity and the high performance of the proposed models. ...

تم النشر في: 2020-06-08 14:48:44