在调查分析现有室内照明LED调光技术和产品的基础上,设计了墙壁开关式的LED调光器与调光驱动电源。为降低对电网的干扰,设计中避免了可控硅导通角控制模式,调光器通过分压方式沿单根电力线(火线)发送2-5 k Hz小幅值(-15 V)电压脉冲...在调查分析现有室内照明LED调光技术和产品的基础上,设计了墙壁开关式的LED调光器与调光驱动电源。为降低对电网的干扰,设计中避免了可控硅导通角控制模式,调光器通过分压方式沿单根电力线(火线)发送2-5 k Hz小幅值(-15 V)电压脉冲调光信号,由驱动电源接收电路检测并解调后改变驱动电路的PWM调光亮度级,调光操作结束后可稳定保持调光亮度级而调光器维持全角导通。调光器工作电流在导通和关断时分别通过单根电力线的电流耦合和分压方式提供,具有静态功耗低、电功率效率和功率因数高、输入电流谐波失真低的特点。展开更多
针对高压设备无线测温装置供电困难问题,设计了一种由低压侧LED光源供电的新型温度在线监测系统。系统使用LED所产生的光能经太阳能电池光电转换后为高压侧无线测温装置供电,以保证其可靠运行。设计了LED两级可PWM调光恒流驱动电路,为LE...针对高压设备无线测温装置供电困难问题,设计了一种由低压侧LED光源供电的新型温度在线监测系统。系统使用LED所产生的光能经太阳能电池光电转换后为高压侧无线测温装置供电,以保证其可靠运行。设计了LED两级可PWM调光恒流驱动电路,为LED提供了恒定电流的同时保证了输入端高功率因数。无线测温装置利用热敏电阻PT1000采集温度信号,并通过ANT无线模块进行数据传输,兼具高精度测量和低功耗优势。实验测得无线测温装置在3.3 V供电电压下的平均消耗电流约7.24 m A,驱动电路在满PWM占空比下输出电流为584 m A,在70%PWM占空比下的工作状态为兼顾高压侧电路可靠运行与节约电能的最佳状态。展开更多
Several improvements have been made to the conventional segmented linear light-emitting diode (LED) driver topology to enhance the performance and reliability of the system. A compensation technology is proposed to ...Several improvements have been made to the conventional segmented linear light-emitting diode (LED) driver topology to enhance the performance and reliability of the system. A compensation technology is proposed to adaptively adjust the impedance of the sensing circuit to keep the output luminance constant in case of line volt- age variations. Based on the proposed technology, an active over temperature protection technique is presented to constrain the averaged LED current according to the junction temperature to prevent the driving IC from overheating. Otherwise, a pulse width modulation dimming circuitry which is compatible with input logic level ranging from 1.8 to 20 V is proposed. The proposed technologies are implemented in a 1.0μm 5/20/500 V BCD technol- ogy with three high voltage MOSFETs integrated on chip. The experimental results show that within 220± 15% V, 50 Hz AC line-voltage variation, the output luminance is restrained to 4% in total. The output luminance can also be effectively controlled by the PWM dimming circuitry, and a dimming range of 95% is achieved with good linearity.展开更多
文摘在调查分析现有室内照明LED调光技术和产品的基础上,设计了墙壁开关式的LED调光器与调光驱动电源。为降低对电网的干扰,设计中避免了可控硅导通角控制模式,调光器通过分压方式沿单根电力线(火线)发送2-5 k Hz小幅值(-15 V)电压脉冲调光信号,由驱动电源接收电路检测并解调后改变驱动电路的PWM调光亮度级,调光操作结束后可稳定保持调光亮度级而调光器维持全角导通。调光器工作电流在导通和关断时分别通过单根电力线的电流耦合和分压方式提供,具有静态功耗低、电功率效率和功率因数高、输入电流谐波失真低的特点。
文摘针对高压设备无线测温装置供电困难问题,设计了一种由低压侧LED光源供电的新型温度在线监测系统。系统使用LED所产生的光能经太阳能电池光电转换后为高压侧无线测温装置供电,以保证其可靠运行。设计了LED两级可PWM调光恒流驱动电路,为LED提供了恒定电流的同时保证了输入端高功率因数。无线测温装置利用热敏电阻PT1000采集温度信号,并通过ANT无线模块进行数据传输,兼具高精度测量和低功耗优势。实验测得无线测温装置在3.3 V供电电压下的平均消耗电流约7.24 m A,驱动电路在满PWM占空比下输出电流为584 m A,在70%PWM占空比下的工作状态为兼顾高压侧电路可靠运行与节约电能的最佳状态。
基金Project supported by the National Natural Science Foundation of China(No.61106026)
文摘Several improvements have been made to the conventional segmented linear light-emitting diode (LED) driver topology to enhance the performance and reliability of the system. A compensation technology is proposed to adaptively adjust the impedance of the sensing circuit to keep the output luminance constant in case of line volt- age variations. Based on the proposed technology, an active over temperature protection technique is presented to constrain the averaged LED current according to the junction temperature to prevent the driving IC from overheating. Otherwise, a pulse width modulation dimming circuitry which is compatible with input logic level ranging from 1.8 to 20 V is proposed. The proposed technologies are implemented in a 1.0μm 5/20/500 V BCD technol- ogy with three high voltage MOSFETs integrated on chip. The experimental results show that within 220± 15% V, 50 Hz AC line-voltage variation, the output luminance is restrained to 4% in total. The output luminance can also be effectively controlled by the PWM dimming circuitry, and a dimming range of 95% is achieved with good linearity.