These two methods can alleviate the inrush current . this paper research voltage and current close - loop control flyback converter and isolated boost converter with peak current mode pwm controller . the start process of flyback converter is divided into three stages : inrush current , current regulating and voltage regulating stages 分析了两个起动过程: 1 )电压电流双闭环控制flyback变换器的起动过程,可分为电流过冲阶段,电流调节器调节阶段和电压调节器调节阶段三个阶段。
A white led driver circuit is presented in this paper . the circuit drives up to four white leds with regulated constant current for uniform intensity . by utilizing proprietary adaptive 1x / 1 . 5x modes and ultra - low - dropout current regulators , it maintains the highest possible efficiency over the full 1 - cell li + battery input voltage range 整体电路以恒定电流驱动4只白光led ,利用1倍/ 1 . 5倍分数型电荷泵和低压差电流调节器,在整个锂电池供电电压范围内保持最高的效率,并使四个白光led获得均匀的亮度。
This paper studies on used the ac servo system based on ti dsp ( lf2407a ) and the foc and digital signal processing thorem , achieves following results : algorithm . we employ svpwm ( space voltage pwm ) algorithm , improve the efficiency of the electric source , and decrease the harmonious elements . we build the mathematic model of the system and simulate it on matlab platform , dsigne segmented pid regulator to adapt variable speed and widen the speed range . measurement . the velocity and electric current measuring , we adopt multi - sampling - rate and digital filter principles . as more improvements we make , the whole system gets a good results . . pc control . the complete controlling system can be controlled remotely . so we develop the pc controlling program . 采用磁场定向脉宽调制算法，提高了电源利用率，降低了逆变电压的谐波，改善了电机的运行特性，降低了对电网的污染；在matlab平台上建立了交流永磁同步伺服电机和电压空间矢量脉宽调制控制系统的数学模型，在仿真的基础上，对传统pid调节器进行了改进，提出转速调节器和电流调节器采用分段pid结构，根据给定转速所处的区间，自动选择相应pid调节器的参数，拓宽了调速范围，提高了控制精度。
