基于L6562的金卤灯电子镇流器恒功率控制技术

设计了一种可用于小功率金属卤化物（MH）灯的电子镇流器。电路的主要特点是成本低,电路简单,可靠性高。利用L6562内部自带的运算放大器根据输入电压和负载的变化而引入负反馈,以达到近似恒功率控制的控制策略。实验结果表明,当灯电压变化±15%左右时,采用该控制策略,输出功率变化可控制在5%左右。     

一种直流供电的陶瓷金卤灯电子镇流器

设计了一款低压直流供电的陶瓷金卤灯电子镇流器.前级采用具有RCD吸收电路的反激变换器.提高镇流器的效率.后级采用低频方波全桥逆变电路.有效克服陶瓷金卤灯的声共振现象.利用单片机实现陶瓷金卤灯的平滑启动、精密恒功率控制、重启动以及各种异常状态保护.测试表明,该电子镇流器性能稳定,效率较高.     

金卤灯二级拓扑电子镇流器控制策略的研究

金卤灯启动过程包括上电、点火、过渡、升压和稳态五个阶段,在整个过程中存在强烈的非线性特性,特别是在灯击穿后,将会出现负阻特性,因此电子镇流器要采用不同的控制策略,使灯能够从一个阶段顺利地进入下一个阶段。为了节约成本,提高灯的使用效率,本文采用二级拓扑电路代替传统的三级拓扑结构,采PFC级和金桥DC／AC级电路,实现小功率金卤灯的稳定启动。     

数字控制金卤灯电子镇流器样机设计

本文基于金卤灯电子镇流器数字控制策略分析的基础上,对其电路拓扑的主电路和控制电路进行设计,即对PFC、DC/DC、DC/AC三级结构的主电路及控制电路模型和参数进行选择、设计,并研制了一台高功率因数低频方波输出的数字控制金卤灯电子镇流器,通过对实验结果分析验证了所提出的数字控制方案是可行的。     

电子镇流器浅析

本文简要介绍了电子镇流器的发展历史、性能特点、工作原理及其发展趋势。     

高功率因数电子镇流器

具有有源功率因数校正、安全保护和预热启动功能的高可靠和高效率荧光灯电子镇流器电路如图1。只要适当调整输出级LC串联谐振电路中扼流圈L2的电感值,则可配接40W到60W荧光灯;通过改变输出电路设计,也可以并接30W双管荧光灯。该电子镇流器的工作频率为40kHZ,功率因数高于 0.98,效率不低于 95％。     

基于AVR单片机的电子镇流器设计

电子镇流器(Electrical ballast)是镇流器的一种,是指采用电子技术驱动电光源,使之产生所需照明的电子设备。电子镇流器自身功耗低,有更佳的照明效果,消除了闪频现象,发光更稳定,而且可以调光。文章采用AVR单片机作为控制芯片,通过电子镇流器进行调光和相关功能的控制,最大限度地发挥智能型镇流器的特点。实际应用表明,文中的方法有效。     

由RI2155驱动的高功率因数电子镇流器

本文介绍了一种由ＩＲ２１５５驱动的电子镇流器功能特点和工作原理。     

Acoustic-Resonance-Free High-Frequency Electronic Ballast for Metal Halide Lamps

To avoid the acoustic resonance on operating metal halide lamps, an autofrequency-searching method is implemented on the high-frequency electronic ballast. The proposed method allows the use of a high-frequency electronic ballast, making the ballast able to adjust the operating frequency automatically as soon as the acoustic resonance is detected and, consequently, to locate it at a stable frequency. The electronic ballast achieves a high efficiency and a high power density through the employment of a high-frequency resonant inverter with an embedded buck-boost converter for power-factor correction and lamp power regulation. The control strategy is realized by a microprocessor along with the acoustic-resonance detection circuit. The operation of autofrequency searching is illustrated by the experiments on an electronic ballast designed for 70-W metal halide lamps.      

Arc Dynamic Stabilization in Low-Frequency Square-Wave Electronic Ballast for Metal Halide Lamps

Discharge lamps present a negative dynamic characteristic that makes necessary to use a current limiting element. In high-frequency resonant ballasts, current limitation is performed by the output resonant tank; but in low-frequency square-wave electronic ballasts, arc stabilization is accomplished by the stage feeding the square wave inverter. Therefore, the design of the input converter must be made taking into account the lamp dynamic characteristic. In the present paper, a new procedure to obtain the small-signal dynamic characteristic of metal halide lamps is proposed. Using the proposed methodology, the small-signal characteristic of a 70-W lamp is obtained. This characteristic is then used for the design of an electronic ballast based on a buck-boost converter followed by a full bridge inverter. The limits for stable operation obtained are verified using a laboratory prototype.     

A Single-Stage High-Power-Factor Electronic Ballast Based on Integrated Buck Flyback Converter to Supply Metal Halide Lamps

In this paper, a novel single-stage electronic ballast with a high power factor is presented. The ballast circuit is based on the integration of a buck converter to provide the power factor correction, and a flyback converter to control the lamp power and to supply the lamp with a low-frequency square-waveform current. Both converters work in discontinuous conduction mode, which simplifies the control. In spite of being an integrated topology, the circuit does not present additional stress of voltage or current in the main switch, which handles only the flyback or buck current, depending on the operation mode. To supply the lamp with a low-frequency square-wave current to avoid acoustic resonances, the flyback has two secondary windings that operate complementarily at a low frequency. The design procedure of the converters is also detailed. Experimental results from a 35-W metal halide lamp are presented, where the proposed ballast reached a power factor of 0.95, a total harmonic distortion of 30% (complying with IEC 61000-3-2), and an efficiency of 90%.     

Study of Igniter in Low-Frequency Square Wave Electronic Ballasts for Metal Halide Lamps

Metal halide lamps (MHLs) have serious acoustic resonance problem. The most widely used method to achieve acoustic-resonance free is to use low-frequency square wave (LFSW) electronic ballasts. There are two ignition methods commonly used in LFSW electronic ballast: high-frequency resonance ignition and additional pulse igniter. This paper analyzed the problems during ignition while using the conventional additional pulse igniter and proposed some solutions. A novel high-frequency resonance igniter is also proposed, where no extra semiconductors and feedback control circuit are needed to perform the ignition. High-voltage ignition pulses are obtained by utilizing the fast polarity inversion of the output voltage of full-bridge inverter. Theoretical analysis, simulation, and experiment results of a prototype for 70-W MHLs verified the effectiveness of both the proposed solutions and the igniter.     

2.65-MHz Self-Oscillating Complementary Electronic Ballast With Constant-Lamp-Current Control for a Metal Halide Lamp

This paper presents the design and implementation of the 2.65-MHz self-oscillating complementary electronic ballast with a constant-lamp-current control for a metal halide lamp. In order to avoid the inherent acoustic-resonance problem of metal halide lamps, the ballast's switching-frequency level was selected to be 2.65 MHz, which satisfies higher magnitudes of maximum electromagnetic interference (EMI) limitation at frequencies of between 2.5 to 3.0 MHz, within the EMI/electromagnetic compatibility frequency range ldquochimney,rdquo for RF lighting systems. With the constant-lamp-current control scheme, the lamp current can be regulated to be less dependent on the input ac voltage. Finally, a 20-W prototype ballast is implemented to demonstrate the ability to avoid the acoustic-resonance and to provide constant levels of lamp current.     

金属卤化物灯制造技术的新技术

金属卤灯是新一代的电光源，它具有高光效，高显色性和长奉命等特性，本文主要介绍了金属卤化物灯目前的最新研究成果及未来的发展动态。     

电子镇流器专用芯片L6574的应用

本文介绍了使用ST公司的L6574芯片驱动两支日光灯管及多片L6574芯片组合驱动多支日光灯管的应用电路。     

金属卤化物灯的近期发展和在产业中的应用

金属卤化物灯具有光效高，显色性好的光电特性，能满足产业应用中的各种特殊要求。本文简要介绍了金属卤化物灯的种类，特性和近期的发展，以及在印刷，制板，光学仪器，汽车照明，水产，植物培育等产业方面的应用。     

金属卤化物灯的高频点灯和放电稳定化

为了提高金属卤化物灯的光效，将该灯用电子镇流器在高频下燃点，观察到灯的不稳定性，称为音响共鸣现象。为了克服音响共鸣现象，介绍了四种稳定工作的方法：①在超音响共鸣的频率下工作；②在矩形波下工作；③采用适当的调制频率下工作；④采用三次谐波叠加高频正弦波点灯。本文介绍金属卤化物灯用电子镇流器、高频点灯和放电稳定化。