A two-staged electronic ballast with wide dimming range, high power factor(PF) and low electromagnetic interference(EMI) is presented. It changes the input voltage of the stage of power inverter for dimming control, s...A two-staged electronic ballast with wide dimming range, high power factor(PF) and low electromagnetic interference(EMI) is presented. It changes the input voltage of the stage of power inverter for dimming control, so it overcomes some limitations of traditional electronic ballasts that use frequency variation. At the same time, the stage of power inverter runs under the soft-switching at the fixed switching frequency and reduces EMI greatly. Its principle and characteristic are analyzed in detail,and experimental and simulated results are obtained on a 40 W fluorescent lamp.展开更多
A complete research of two different starting techniques for HPS lamps driven by electronic ballast is presented while a traditional starting technique based on the series resonant theory which is used widely for fluo...A complete research of two different starting techniques for HPS lamps driven by electronic ballast is presented while a traditional starting technique based on the series resonant theory which is used widely for fluorescent lamps starting is analyzed in detail. An improved nth harmonic resonant technique is also simulated. Furthermore, a novel starting technique based on a pulse transformer is proposed, which still offer the automatic switch off capability. The differences between two starting techniques are explained. The experimental results from a lab prototype are used to verify the design.展开更多
A single-stage single-switch high- frequency electronic ballast topology is presented. The circuit topology is the integration of a buck power- factor-correction (PFC) converter and a class E resonant inverter with ...A single-stage single-switch high- frequency electronic ballast topology is presented. The circuit topology is the integration of a buck power- factor-correction (PFC) converter and a class E resonant inverter with only one active power switch. The buck converter is operated in discontinuous conduction mode and at a fixed switching frequency, and constant duty cycle to achieve high power factor and it can be controlled easily. Detailed analysis of the operation and characteristics of the circuit is provided. Simulation results satisfy present standard requirements.展开更多
文摘A two-staged electronic ballast with wide dimming range, high power factor(PF) and low electromagnetic interference(EMI) is presented. It changes the input voltage of the stage of power inverter for dimming control, so it overcomes some limitations of traditional electronic ballasts that use frequency variation. At the same time, the stage of power inverter runs under the soft-switching at the fixed switching frequency and reduces EMI greatly. Its principle and characteristic are analyzed in detail,and experimental and simulated results are obtained on a 40 W fluorescent lamp.
文摘A complete research of two different starting techniques for HPS lamps driven by electronic ballast is presented while a traditional starting technique based on the series resonant theory which is used widely for fluorescent lamps starting is analyzed in detail. An improved nth harmonic resonant technique is also simulated. Furthermore, a novel starting technique based on a pulse transformer is proposed, which still offer the automatic switch off capability. The differences between two starting techniques are explained. The experimental results from a lab prototype are used to verify the design.
文摘A single-stage single-switch high- frequency electronic ballast topology is presented. The circuit topology is the integration of a buck power- factor-correction (PFC) converter and a class E resonant inverter with only one active power switch. The buck converter is operated in discontinuous conduction mode and at a fixed switching frequency, and constant duty cycle to achieve high power factor and it can be controlled easily. Detailed analysis of the operation and characteristics of the circuit is provided. Simulation results satisfy present standard requirements.