转换开关

This topic uses the switching mode is the entire bridge all controls the rectification filter, moreover the power source has also utilized the soft switch technology, causes its loss to reduce obviously, the DC-DC transformation use cuts the wave boosted circuit to realize, the structure is simple, the transfer efficiency is high; Selects the small breakover resistance, the high shutter speed P60N06 tube for the switching valve, to select the quick recovery diode rectification, reduces the reverse breakover time, reduces the loss.

本课题采用的开关方式是全桥全控整流滤波，而且电源还运用了软开关技术，使它的损耗明显降低，DC-DC变换使用斩波升压电路来实现，结构简单，转换效率高；选用小导通电阻、高开关速度的P60N06管为开关管、选用快速恢复二极管整流，减少反向导通时间，降低损耗。

This topic returns in view of the cut type switch spreads the type switch "to return for the predecessor design spreads the type electric power switch utilization in the LED lamps and lanterns" is the research direction, to achieve take reduces the power loss to replace the tradition operational amplifier pulse wave width accent as the goal using IC UC3842 changes part, the actuation returns spreads the type electric power switch's switch of Power MOSFET, so as to controls instead spreads the type electric power switch breakover closure's time then control voltage output size, achieves the output voltage to the load LED lamps and lanterns adjusts the LED lamps and lanterns brightness the goal.

各位大大抱歉~！因为英文底子不好！希望大家帮忙翻译一下，希望不要用翻译软体翻的最好是自己翻！拜托了！本专题针对切换式转换器的返驰式转换器为前身设计「返驰式电力转换器运用在LED灯具」为研究方向，为达到以减少功率损失为目的利用IC UC3842代替传统运算放大器脉波宽度调变部分，驱动返驰式电力转换器的Power MOSFET之开关，藉以控制反驰式电力转换器导通截止的时间进而控制电压输出的大小，输出电压至负载LED灯具达成调节LED灯具亮度的目的。

Later, it makes some comparison with four kinds of modulation technique, and finally, it implements the three-level PWM switching power amplifier with the PWM technique. The power of the amplifier is 2kVA, and the frequency bandwidth is 10～3kHz. In the thesis, the author designs and makes the hardwares of the switching power amplifier. The hardwares contain power inverter rank circuit, control system circuit based on DSP, drive and isolation circuit, and protective circuit. The thesis also analyses the potential safety problems and put forward some solutions for the problems. Furthermore, the thesis accomplishes the software design of the control system, and successfully debugs it. The methods of designing higher power ampilfier are also discussed in the thesis. It analyses the feasibility of the methods, outlines the way of how to design higher power switching power amplifier, and does some experiments with the method of switches-parallelling.

根据电动振动试验系统对开关功放的要求，提出了以电感电流瞬时值控制技术为基础的三电平脉宽调制开关功放的设计方案，并通过系统仿真进行了原理性论证；然后设计并制作了开关功放的硬件，包括功率转换电路，基于DSP的控制电路，驱动、隔离电路以及保护电路；针对开关功放数学模型不易得出的特点，细致分析了模糊自适应PID控制方法，在此基础上编写了控制程序；研制出一台功率为2kVA，通频带为10～3kHz的三电平脉宽调制开关功放；论文中还探讨了实现大功率开关功放的方法，分析了各种方法的可行性，给出了实现大功率开关功放的思路，并进行了并联开关管实现大功率开关功放的实验。

In the design of the power supply, the main circuit topology frame uses full-bridge series resonant switching and parallel load connection, in which, four MOSFETs are adopted as the power switches, and by four pulses which UC3879 produces, high frequency operation and fast response are realized. In addition, the MOSFET in the switching power supply has no hard turn-on or turn-off situation in transition, thus the disturbance to the power system is avoided. Especially,by the use of high frequency transformer, PQ50/50, the switching power system can provide the steady discharge current without any amperite.

此开关电源采用全桥软开关技术、串联谐振并联输出，四个MOSFET管为主控制开关元件，通过脉冲产生电路UC3879产生的四路相关脉冲实现了高频交替开关，同时能快速响应输出的各种变化；避免了开关管的硬开关，提高了转换效率，另外通过采用高频变压器PQ50/50隔离了原副边，减小了高次谐波对电网干扰；无需镇流电阻也可实现气体稳定放电。

If the conversion switch which positions on the controllable plate at steering room to "bridge" position, steering gears is operated at bridge.

转换开关放在&驾驶室&位置则由驾驶室操舵。

If failed in starting,control box will have sound alarm and machine will be locked up.

起动成功后，控制箱控制自动切换屏的转换开关，切换供电电路。

After successful starting, the control box will control the switch of the ATS to switch electric circuits of power supply.

从电网发生故障到备用机组向用电设备供电的时间为8-12S ，在市电恢复正常后，控制箱控制转换开关再次切换供电电路，恢复由电网供电，同时控制发动机空载运行发动机温度平衡并降低后，自动停机。

The transfer sequence of the transfer switch can be appraised by transfer test:if all performance indices meet the design requirements,its transfer capability can thus be ensured,which is proved by years'practices.

因此，在有载调压开关运行前必须做此试验。1有载调压开关的工作顺序有载调压开关是由电动机构、切换开关、分接选择器和转换选择器3大部分组成。

The capacitance pressure sensor converts the outside pressure exchanging signals into the capacitance changing values; the multi-way switch switches the capacitances of the two sides; the capacitance frequency converting circuit is the self-exciting oscillator circuit and converts the measured capacitance signals output by the multi-way switch into the frequency signals.

其中，电容式压力传感器：用于将外界压力变化信号转换为电容变化值；多路开关：用于对两侧电容进行切换；电容频率转换电路：其为一自激振荡电路，用于对多路开关输出的被测电容信号转换成频率信号。

The main purpose of this thesis is to research and develop three different kinds of battery chargers of resonant-switch converters. Starting with the zero voltage switch and the zero current switch converters, which employ the quasi-resonant converter technique, we gain the best parameters of the resonance components from the characteristic curve diagrams of these two converters. Then we design battery chargers based on these two structures and use them to experiment on lead-acid batteries.

中文摘要本论文之主要目的在於研制三种不同的共振开关式转换器蓄电池充电器，先探讨半共振式技术的零电压以及零电流转换器，利用这两种转换器的特性曲线图设计出共振元件最佳的参数值，以这两种架构作为蓄电池充电器，来对铅酸蓄电池做充电测试，经实验测得，零电压切换半共振式降压型转换器之充电器的开关在零电压的时候导通和截止。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。