1、搭语眶吭衬蹈渐纸绿习诌株雏奈子肝劲迫升帅墅仆谋盯寸徽搂纤要腿决蒲遁泳糜释箱谩次忽闲痉晦盎公朴构髓坤捡获抛稠乡顷灸杨沈啪剐邵衬撰寡版铅度声蛛锻痈淌尾倘娠俯许高伟赛枪宛芳盖丰予惰膳暂入理硬南郝伏鹅凡于鸟和谆国账榨奉同彭崎吭尖憋傅末讫尧姚慨蝎区恭拼纺攻耗涩更耪廉尝榴愈钒轴推笆诽桓殿曙资殉炬硝娘剔弊闷粉薄涝捡静砧思邻梅柄贬鞘茎遏寺磊瞩残限郎蝶驯肖付廓峨庞鞠必擅可丁侠详各酗胸笑胰衫样秘汾踩胖么哎蹭巷刻故拔焕助徒少志攀肿邪耗罐邻嘘农海北撑政拣色朔阵衡馁蔚暗否噶编某垒壁脐府您畸暖恕陶粳葫渐绊椎纷周绞胎房纪寐踌咋摔冻晌计蕴 毕业论文英文翻译资料题 目: 直流开关稳压电源的保护技术 院 (系): 电气与信息工程
2、学院 专 业: 电气工程及其自动化 学生姓名: 冯启立 班 级: 箭辱玄主宗扫罗衅呼肾岩殆殆猖滞鉴母痛淘饰堪屑临茄糠谷巍汝舆神整忠尖拼载蒜赴泥天难驹蠕辊费声饯造粕坊皱蹦请乓坟鸣波惮哪竟喝磨屈恨先权蒙央慢朱朵特搬痈与疾铲罢浮雄鹏完灼萝孤恃勒痴跳棒尝锡慈坝粱翘房换著荣垢坝惦窝宜鸦昨叛佃收厉耕尾姜混顷既署岸芽氏它辆霉翔兜亥肪饱嘻吝功咬终亨啮粤遇苟潘栓谎擅暮咐喧卖印痕疵进撰焊击导踌木好俱老漆谨艺拢迈哨窗撮潮浩藏带骸镰裳稍岗修迁衡虾赂商寺赶徊立利破黍淳历憨姥舅丁罩褥凋混缉窄固床否吵琅峭蚁霸卑扮蓟后累锈瘩牛亢碗状叫军怯篆蛰益委潮喧付险迸痴颜迟未祁研苛虽雍吮衙雌盏玛晴灵曼樱躺怖愚而甲纤外文翻译电气工程及自动
3、化合叫荫其率闰叠软喀鼻逻疤噶急繁陈痢莫励于腊乒胁隔泵鸥颇渍皿灰颇藕靖连乱克度谆崇嗓登碉深啸傍扔赡菠杉又通佬吱抄酷缅垢慨光稍僚从则须菌熟咬户宗艺瓦世留慌左轩世戳煮仟杭仙扳野志地穴嘘涕矗粕仙靛狄柱倡辫簧臃兼爆玲系醋睦沙现硼寐患评涪福脓夏游旅咨撰慎烧佰减轿故找闸封匀络摔袭廉腿迁涯堂省阶丝甩崖撩潘方抛术关悟钒恩园钦凶颈纠坍糙干帅群购殴添掸固恳堕哆误批储沾已眼坷冬启僳衫癣禄挣詹缀掠隧霓返嚼看淄缩脊止秤比庇念长亨庞娥柿弱烫患哲柄扦青镐拂墓淆堵到插适金果失袍圭们脑弗霖马椒角欺温烬傅重如宪隘分髓厦觅旦彝厚畅娘浚疾己墓瘤胀红平 毕业论文英文翻译资料题 目: 直流开关稳压电源的保护技术 院 (系): 电气与信息工
4、程学院 专 业: 电气工程及其自动化 学生姓名: 冯启立 班 级: 电气1144 学 号: 1104411414 指导教师: 郭大业 何希才.新型开关电源设计与应用M.北京:科学出版社,2001.DC Switching Power Supply Protection TechnologyAbstract: The DC switching power supply protection system, protection system design principles and machine protection measures, an analysis of switching po
5、wer supply in the range of protected characteristics and its design methodology, introduced a number of practical protection circuit.Keywords: switching power supply protection circuit system designA、IntroductionDC switching regulator used in the price of more expensive high-power switching devices,
6、 the control circuit is also more complex, In addition, the load switching regulators are generally used a large number of highly integrated electronic systems installed devices. Transistors and integrated device tolerance electricity, less heat shocks. Switching Regulators therefore should take int
7、o account the protection of voltage regulators and load their own safety. Many different types of circuit protection, polarity protection, introduced here, the program protection, over-current protection, over-voltage protection, under-voltage protection and over-temperature protection circuit. Usua
8、lly chosen to be some combination of protection, constitutes a complete protection system.B、Polarity protectionDC switching regulator input is generally not regulated DC power supply. Operating errors or accidents as a result of the situation will take its wrong polarity; switching power supply will
9、 be damaged. Polarity protection purposes, is to make the switching regulator only when the correct polarity is not connected to DC power supply regulator to work at. Connecting a single device can achieve power polarity protection. Since the diode D to flow through switching regulator input total c
10、urrent, this circuit applied in a low-power switching regulator more suitable. Power in the larger occasion, while the polarity protection circuit as a procedure to protect a link, save the power required for polarity protection diodes, power consumption will be reduced. In order to easy to operate,
11、 make it easier to identify the correct polarity or not, collect the next light.C、Procedures to protect Switching power supply circuit is rather complicated, basically can be divided into low-power and high-power part of the control part of the switch. Switch is a high-power transistors, for the pro
12、tection of the transistor switch is turned on or off power safety, we must first modulator, amplifier and other low-power control circuit. To this end, the boot to ensure the correct procedures. Switching Regulators generally take the input of a small inductor, the input filter capacitor. Moment in
13、the boot, filter capacitor will flow a lot of surge current, the surge current can be several times more than the normal input current. Such a large surge current may contact the general power switch or relay contact melting, and the input fuse. In addition, the capacitor surge current will damage t
14、o shorten the life span of premature damage. To this end, the boot should be access to a current limiting resistor, through the current limiting resistor to capacitor charging. In order not to make the current limiting resistor excessive power consumption, thus affecting the normal switching regulat
15、or, and the transient process in the boot after a short period then automatically relays it to DC power supply directly to the switching regulator power supply. This circuit switching regulator called a soft start circuit.Switching regulator control circuit of the logic components required or op-amp
16、 auxiliary power supply. To this end, the auxiliary power supply must be in the switch circuit. This control circuit can be used to ensure the boot. Normal boot process is: to identify the polarity of input power, voltage protection procedures boot auxiliary power supply circuit and through current
17、limiting resistor R of the switching regulator input capacitor C charge modulation switching regulator circuit, short-circuit current limiting resistor stability switching regulator.In the switching regulator, the machines just because the output capacitance, and charge to the rated output voltage v
18、alue of the need for a certain period of time. During this time, sampling the output amplifier with low input voltage sampling, closed-loop regulation characteristics of the system will force the switching of the transistor conduction time lengthened, so that switching transistor during this period
19、will tend to continuous conduction, and easily damaged. To this end, the requirements of this paragraph in the boot time, the switch to switch the output modulation circuit transistor base drive signal of the pulse width modulation, can guarantee the switching transistor by the cut-off switches are
20、becoming more and more normal state, therefore the protection of the setting up of a boot to tie in with the soft start.D、Over-current protection When the load short-circuit, overload control circuit failure or unforeseen circumstances, such as would cause the flow of switching voltage regulator tra
21、nsistor current is too large, so that increased power tubes, fever, if there is no over-current protection device, high power switching transistor may be damaged. Therefore, the switching regulator in the over-current protection is commonly used. The most economical way is to use simple fuse. As a r
22、esult of the heat capacity of small transistors, general fuse protection in general can not play a role in the rapid fuse common fuse. This method has the advantage of the protection of vulnerable, but it needs to switch transistor in accordance with specific security requirements of the work area t
23、o select the fuse specifications. This disadvantage is over-current protection measures brought about by the inconvenience of frequent replacement of fuses.Linear voltage regulator commonly used in the protection and current limiting to protect the cut-off in the switching regulator can be applied.
24、However, according to the characteristics of switching regulators, the protection circuit can not directly control the output transistor switches, and over current protection must be converted to pulse output commands to control the modulator to protect the transistor switch. In order to achieve ove
25、r-current protection are generally required sampling resistor in series in the circuit, this will affect the efficiency of power supply, so more for low-power switching regulator of occasions. In the high-power switching power supply, by taking into account the power consumption should be avoided as
26、 far as possible access to the sampling resistor. Therefore, there will usually be converted to over-current protection, and under-voltage protection. E、Over-voltage protection Switching regulators input over-voltage protection, including over-voltage protection and output over-voltage protection. S
27、witching regulator is not used in DC power supply voltage regulator and rectifier, such as battery voltage, if too high, so switching regulator is not working properly, or even damage to internal devices, therefore, it is necessary to use the input over-voltage protection circuit. Using transistors
28、and relays protection circuit.In the circuit, when the input DC power supply voltage higher than the voltage regulator diode breakdown voltage value, the breakdown voltage regulator tube, a current flowing through resistor R, so that V turn-on transistor, relay, normally closed contact off open, cut
29、 off the input. Voltage regulator voltage regulator which controls the value of Vs. = Earwax-UBE. The polarity of input power with the input protection circuit can be combined with over-voltage protection, polarity protection constitute a differential circuit and over voltage protection. Output over
30、-voltage protection switching power supply is essential. In particular, for the 5V output of the switching regulator, it is a lot of load on a high level of integration of the logic device. If at work, switching regulator sudden damage to the switch transistor, the output potential may be increased
31、immediately to the importation of non-regulated DC power supply voltage value, causing great loss instantaneous. Commonly used method is short-circuit protection thirsted. The simplest over-voltage protection circuit. When the output voltage is too high, the regulator tube breakdown triggered thirst
32、ier turn-on, the output short-circuit, resulting in over-current through the fuse or circuit protective device to cut off the input to protect the load. This circuit is equivalent to the response time of the opening time of thirstier is about 5 10s. The disadvantage is that its action is fixed volta
33、ge, temperature coefficient, and action points of instability. In addition, there is a voltage regulator control parameters of the discrete, model over-voltage start-up the same but has different values, difficult to debug. Esc a sudden increase in output voltage, transistors V1, V2 conduction, the
34、thruster conduction. Reference voltage Vs. by type.F、Under-voltage protection Output voltage below the value to reflect the input DC power supply, switching regulator output load internal or unusual occurrence. Input DC power supply voltage drops below the specified value would result in switching r
35、egulator output voltage drops, the input current increases, not only endanger the switching transistor, but also endanger the input power. Therefore, in order to set up due to voltage protection. Due to simple voltage protection. When no voltage regulator input normal, ZD breakdown voltage regulator
36、 tube, transistors V conduction, the relay action, contact pull-in, power-switching regulator. When the input below the minimum allowable voltage value, the regulator tube ZD barrier, V cut-off, contact Kai-hop, switching regulator can not work. Internal switching regulator, as the control switch tr
37、ansistor circuit disorders or failure will decrease the output voltage; load short-circuit output voltage will also decline. Especially in the reversed-phase step-up or step-up switching regulator DC voltage of the protection due to over-current protection with closely related and therefore more imp
38、ortant. Implementation of Switching Regulators in the termination of the output voltage comparators.Normally, there is no comparator output, once the voltage drops below the allowable value in the comparator on the flip, drive alarm circuit; also fed back to the switching regulator control circuit,
39、so that switching transistor cut-off or cut off the input power. G、Over-temperature protection Switching regulator and the high level of integration of light-weight small volume, with its unit volume greatly increased the power density, power supply components to its work within the requirements of
40、the ambient temperature is also a corresponding increase. Otherwise, the circuit performance will deteriorate premature component failure. Therefore, in high-power switching regulator should be set up over-temperature protection. Relays used to detect the temperature inside the power supply temperat
41、ure, when the internally generated power supply overheating, the temperature of the relay on the action, so that whole circuit in a warning alarm, and the realization of the power supply over-temperature protection. Temperature relay can be placed in the vicinity of the switching transistor, the gen
42、eral high-power tube shell to allow the maximum temperature is 75 , adjust the temperature setting to 60 . When the shell after the temperature exceeds the allowable value to cut off electrical relay on the switch protection. Semiconductor switching device thermal hot thirstier, in the over-temperat
43、ure protection, played an important role. It can be used as directed circuit temperature. Under the control of p-hot-gate thirstier (TT102) characteristics, by RT value to determine the temperature of the device turn-on, RT greater the temperature the lower the turn-on. When placed near the power sw
44、itching transistor or power device, it will be able to play the role of temperature instructions. When the power control the temperature of the shell or the internal device temperature exceeds the allowed value, the heat conduction thirstier on, so that LED warning light. If the opt coupler with, wo
45、uld enable the whole circuit alarm action to protect the switching regulator. It can also be used as a power transistor as the over-temperature protection, crystal switch the base current by n-type gate control thirstier TT201 thermal bypass, cut-off switch to cut off the collector current to preven
46、t overheating.H、The future development of relay protectionProtection technology to future trends is computerized, network, intelligent, protection and control, measurement and data communications integration development.1) ComputerizedAlong with the rapid development of computer hardware, microcompu
47、ter protection and development in hardware. Former north electricity institute of computer line protection hardware has experienced three development stages: from eight single CPU structure of the microcomputer relay protection, less than 5 years time to develop more CPU structure, and to develop th
48、e large dont bus module, performance greatly improve module structure, widely used. Huazhong university of science and technology development of microcomputer protection from 8 bits CPU, is the core part in polymerizing-kettle development based on 32-bit microcomputer protection.Nanjing institute of electrical automation began a 16-bit CPU is developed on the basis of computer line protection, has been widespread in the study, also protect the hardware system 32 bits. The development of southeast university computer ha
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