Title :
Inductor phase feedback for phase-locked loop control of electronic ballasts
Author :
Lin, Ray-Lee ; Yeh, Ming-Chieh
Author_Institution :
Dept. of Electr. Eng., Nat. Cheng Kung Univ., Tainan, Taiwan
Abstract :
This paper proposes a novel phase-locked loop (PLL) control technique for electronic ballasts, using the phase-feedback signal from the resonant inductor. Generally speaking, the electronic ballast with PLL control has been used to drive some high-voltage lamps with high equivalent resistance at the steady state, such as cold-cathode fluorescent lamps (CCFLs). With the proposed control scheme for electronic ballasts is thus developed to tolerate lower equivalent resistance of the lamps at the steady state, to have the operating frequency of ballasts continuously track the resonant frequency of the resonant tank. Based on the derived analysis of the proposed PLL control scheme, the design and the implementation of a prototype circuit is provided to demonstrate the performance of the proposed PLL scheme associating with a current regulator circuit.
Keywords :
electric current control; fluorescent lamps; inductors; lamp accessories; phase locked loops; PLL control; cold-cathode fluorescent lamp; current regulator circuit; electronic ballast; equivalent resistance; high-voltage lamp; phase feedback signal; phase-locked loop control; resonant frequency; resonant inductor; resonant tank; Circuits; Electronic ballasts; Feedback loop; Fluorescent lamps; Inductors; Performance analysis; Phase locked loops; Resonance; Resonant frequency; Steady-state;
Conference_Titel :
Industry Applications Conference, 2005. Fourtieth IAS Annual Meeting. Conference Record of the 2005
Print_ISBN :
0-7803-9208-6
DOI :
10.1109/IAS.2005.1518851