外文翻譯---光伏系統(tǒng)中蓄電池的充電保護(hù)ic電路設(shè)計(jì)

1、<p>　　光伏系統(tǒng)中蓄電池的充電保護(hù)IC電路設(shè)計(jì)</p><p><b>　　1.引言</b></p><p>　　太陽能作為一種取之不盡、用之不竭的能源越來越受到重視。太陽能發(fā)電已經(jīng)在很多國家和地區(qū)開始普及，太陽能照明也已經(jīng)在我國很多城市開始投入使用。作為太陽能照明的一個(gè)關(guān)鍵部分，蓄電池的充電以及保護(hù)顯得尤為重要。由于密封免維護(hù)鉛酸蓄電池具有密封好、無泄

2、漏、無污染、免維護(hù)、價(jià)格低廉、供電可靠，在電池的整個(gè)壽命期間電壓穩(wěn)定且不需要維護(hù)等優(yōu)點(diǎn)，所以在各類需要不間斷供電的電子設(shè)備和便攜式儀器儀表中有著廣泛的應(yīng)用。采用適當(dāng)?shù)母〕潆妷海谡Ｊ褂?防止過放、過充、過流)時(shí)，免維護(hù)鉛酸蓄電池的浮充壽命可達(dá)12~16年，如果浮充電壓偏差5%則使用壽命縮短1/2。由此可見，充電方式對這類電池的使用壽命有著重大的影響。由于在光伏發(fā)電中，蓄電池?zé)o需經(jīng)常維護(hù)，因此采用正確的充電方式并采用合理的保護(hù)方式，能有

3、效延長蓄電池的使用壽命。傳統(tǒng)的充電和保護(hù)IC是分立的，占用而積大并且外圍電路復(fù)雜。目前，市場上還沒有真正的將充電與保護(hù)功能集成于單一芯片。針對這個(gè)問題，設(shè)計(jì)一種集蓄電池充電和保護(hù)功能于一身的IC是十分必要的。</p><p><b>　　2.系統(tǒng)設(shè)計(jì)與考慮</b></p><p>　　系統(tǒng)主要包括兩大部分:蓄電池充電模塊和保護(hù)模塊。這對于將蓄電池作為備用電源使用的場合

4、具有重要意義，它既可以保證外部電源給蓄電池供電，又可以在蓄電池過充、過流以及外部電源斷開蓄電池處于過放狀態(tài)時(shí)提供保護(hù)，將充電和保護(hù)功能集于一身使得電路簡化，并且減少寶貴的而積資源浪費(fèi)。圖1是此Ic在光伏發(fā)電系統(tǒng)中的具體應(yīng)用，也是此設(shè)計(jì)的來源。</p><p>　　免維護(hù)鉛酸蓄電池的壽命通常為循環(huán)壽命和浮充壽命，影響蓄電池壽命的因素有充電速率、放電速率和浮充電壓。某些廠家稱如果有過充保護(hù)電路，充電率可以達(dá)到甚至超過

5、2C(C為蓄電池的額定容量)，但是電池廠商推薦的充電率是C/20~C/3。電池的電壓與溫度有關(guān)，溫度每升高1℃，單格電池電壓下降4 mV，也就是說電池的浮充電壓有負(fù)的溫度系數(shù)-4 mV/℃。普通充電器在25℃處為最佳工作狀態(tài)；在環(huán)境溫度為0℃時(shí)充電不足；在45℃時(shí)可能因嚴(yán)重過充電縮短電池的使用壽命。要使得蓄電池延長工作壽命，對蓄電池的工作狀態(tài)要有一定的了解和分析，從而實(shí)現(xiàn)對蓄電池進(jìn)行保護(hù)的目的。蓄電池有四種工作狀態(tài):通常狀態(tài)、過電流狀態(tài)

6、、過充電狀態(tài)、過放電狀態(tài)。但是由于不同的過放電電流對蓄電池的容量和壽命所產(chǎn)生的影響不盡相同，所以對蓄電池的過放電電流檢測也要分別對待。當(dāng)電池處于過充電狀態(tài)的時(shí)間較長，則會嚴(yán)重降低電池的容量，縮短電池的壽命。當(dāng)電池處于過放電狀態(tài)的時(shí)間超過規(guī)定時(shí)間，則電池由于電池電壓過低可能無法再充電使用，從而使得電池壽命降低。</p><p>　　根據(jù)以上所述，充電方式對免維護(hù)鉛酸蓄電池的壽命有很大影響，同時(shí)為了使電池始終處于良好

7、的工作狀態(tài)，蓄電池保護(hù)電路必須能夠?qū)﹄姵氐姆钦９ぷ鳡顟B(tài)進(jìn)行檢測，并作出動作以使電池能夠從不正常的工作狀態(tài)回到通常工作狀態(tài)，從而實(shí)現(xiàn)對電池的保護(hù)。</p><p><b>　　3.單元模塊設(shè)計(jì)</b></p><p><b>　　3.1充電模塊</b></p><p>　　芯片的充電模塊框圖如圖2所示。該電路包括限流比較器

8、、電流取樣比較器、基準(zhǔn)電壓源、欠壓檢測電路、電壓取樣電路和邏輯控制電路。</p><p>　　該模塊內(nèi)含有獨(dú)立的限流放大器和電壓控制電路，它可以控制芯片外驅(qū)動器，驅(qū)動器提供的輸出電流為20~30 mA，可直接驅(qū)動外部串聯(lián)的調(diào)整管，從而調(diào)整充電器的輸出電壓與電流。電壓和電流檢測比較器檢測蓄電池的充電狀態(tài)，并控制狀態(tài)邏輯電路的輸入信號。當(dāng)電池電壓或電流過低時(shí)，充電啟動比較器控制充電。電器進(jìn)入涓流充電狀態(tài)，當(dāng)驅(qū)動器截止

9、時(shí)，該比較器還能輸出20 mA左右，進(jìn)入涓流充電電流。這樣，當(dāng)電池短路或反接時(shí)，充電器只能以小電流充電，避免了因充電電流過大而損壞電池。此模塊構(gòu)成的充電電路充電過程分為二個(gè)充電狀態(tài):大電流恒流充電狀態(tài)、高電壓過充電狀態(tài)和低電壓恒壓浮充狀態(tài)。充電過程從大電流恒流充電狀態(tài)開始，在這種狀態(tài)下充電器輸出恒定的充電電流。同時(shí)充電器連續(xù)監(jiān)控電池組的兩端電壓，當(dāng)電池電壓達(dá)到轉(zhuǎn)換電壓過充轉(zhuǎn)換電壓Vsam時(shí)，電池的電量己恢復(fù)到放出容量的70%~90%，充

10、電器轉(zhuǎn)入過充電狀態(tài)。在此狀態(tài)下，充電器輸出電壓升高到過充電壓Voc，由于充電器輸出電壓保持恒定不變，所以充電電流連續(xù)下降。當(dāng)電流下降到過充中止電流Ioct時(shí)，電池的容量己達(dá)到額定容量的100%，充電器輸出電壓下降到較低的浮充電壓VF。</p><p><b>　　3.2保護(hù)模塊</b></p><p>　　芯片內(nèi)部保護(hù)電路模塊框圖如圖3所示。該電路包括控制邏輯電路、取

11、樣電路、過充電檢測電路、過放電檢測比較器、過電流檢測比較器、負(fù)載短路檢測電路、電平轉(zhuǎn)換電路和基準(zhǔn)電路(BGR)。</p><p>　　此模塊構(gòu)成的保護(hù)電路如圖4所示。當(dāng)芯片的供電電壓在正常工作范圍內(nèi)，且VM管腳處的電壓在過電流I檢測電壓之下，則此時(shí)電池處于通常工作狀態(tài)，芯片的充放電控制端CO和DO均為高電平，這時(shí)芯片處于通常工作模式。而當(dāng)電池放電電流變大，會引起VM管腳處的電壓上升，若VM管腳處的電壓在過電流檢測

12、電壓Viov之上，則此時(shí)電池處于過電流狀態(tài)，如果這種狀態(tài)保持相應(yīng)的過電流延時(shí)時(shí)間tiov，芯片禁止電池放電，這時(shí)充電控制端CO為高電平，而放電控制端DO為低電平，芯片處于過電流模式，一般為了對電池起到更加安全合理的保護(hù)，芯片會對電池的不同過放電電流采取不同的過放電電流延時(shí)時(shí)間保護(hù)。一般規(guī)律是過放電電流越大，則過放電電流延時(shí)時(shí)間越短。當(dāng)芯片的供電電壓在過充電檢測電壓之上（Vdd>Vcu）時(shí)，則電池處于過充電狀態(tài)，如果這種狀態(tài)保持相應(yīng)

13、的過充電延時(shí)時(shí)間tcu芯片將禁止電池充電，此時(shí)放電控制端DO為高電平，而充電控制端CO為低電平，芯片處于過充電模式。當(dāng)芯片的供電電壓在過放電檢測電壓之下(Vdd<Vdl)，則此時(shí)電池處于過放電狀態(tài)，如果這種狀態(tài)保持相應(yīng)的過放電延時(shí)時(shí)間tdl，芯片將禁止電池放電，此時(shí)充電控制端CO為高</p><p><b>　　4.電路設(shè)計(jì)</b></p><p>　　由兩個(gè)充

14、電與保護(hù)模塊結(jié)構(gòu)圖可將電路分為四部分:電源檢測電路(欠壓檢測電路)、偏置電路(取樣電路、基準(zhǔn)電路以及偏置電路)、比較器部分(包括過充電檢測比較器/過放電檢測比較器、過流檢測比較器和負(fù)載短路檢測電路)及邏輯控制部分。</p><p>　　文中主要介紹欠壓檢測電路設(shè)計(jì)(圖5) ，并給出帶隙基準(zhǔn)電路(圖6) 。</p><p>　　蓄電池的充電、電壓的穩(wěn)定尤為重要，欠壓、過壓保護(hù)是必不可少的，因

15、此通過在芯片內(nèi)部集成過壓、欠壓保護(hù)電路來提高電源的可靠性和安全性。并且保護(hù)電路的設(shè)計(jì)要簡單、實(shí)用，此處設(shè)計(jì)了一種CMOS工藝下的欠壓保護(hù)電路，此電路結(jié)構(gòu)簡單，工藝實(shí)現(xiàn)容易，可用做高壓或功率集成電路等的電源保護(hù)電路。</p><p>　　欠壓保護(hù)的電路原理圖如圖5所示，共由五部分組成:偏置電路、基準(zhǔn)電壓、分壓電路、差分放大器、輸出電路。本電路的電源電壓是10V；M0，M1，M2，R0是電路的偏置部分，給后級電路提供

16、偏置，電阻Ro決定了電路的工作點(diǎn)，M0，M1，M2組成電流鏡；R1，M14是欠壓信號的反饋回路；其余M3，M4，M5，M6，M7，M8，M9，M10，M11，M12，M13，M14組成四級放大比較器；M15，DO產(chǎn)生基準(zhǔn)電壓，輸入比較器的同相端，固定不變（V＋），分壓電阻R1，R2，R3輸入到比較器的反相端，當(dāng)電源電壓正常工作時(shí)，反相端的欠壓檢測輸給比較器的反相端的電壓大于V+。比較器輸出為低，M14截止，反饋電路不起作用;當(dāng)欠壓發(fā)生時(shí)

17、，分壓電阻R1，R2，R3反應(yīng)比較敏感，當(dāng)電阻分壓后輸給反相端的電壓小于V，比較器的輸出電壓為高，此信號將M14開啟，使得R兩端的電壓變?yōu)镸兩端的飽和電壓，趨近于0V，從而進(jìn)一步拉低了R1>R2分壓后的輸出電壓，形成了欠壓的正反饋。輸出為高，欠壓鎖定，起到了保護(hù)作用。</p><p>　　5.仿真模擬結(jié)果與分析</p><p>　　本設(shè)計(jì)電路采用CSMC 0.6 μm數(shù)字CMOS工藝

18、對電路進(jìn)行仿真分析。在對電路做整體仿真時(shí)，主要觀察的是保護(hù)模塊對電池的充放電過程是否通過監(jiān)測Vdd電位和Vm電位而使芯片的CO端和DO端發(fā)生相應(yīng)的變化。圖7所示的整體仿真波形圖是保護(hù)模塊隨著電池電壓的變化從通常工作模式轉(zhuǎn)換到過充電模式，然后回到通常工作模式，接著進(jìn)入過放電模式，最后再回到通常工作模式。由于本設(shè)計(jì)處于前期階段，各個(gè)參數(shù)還需要優(yōu)化，只是提供初步的仿真結(jié)果。</p><p><b>　　6.結(jié)

19、論</b></p><p>　　設(shè)計(jì)了一種集蓄電池充電與保護(hù)功能于一身的IC。利用此設(shè)計(jì)既可以減小而積，又可以減少外圍電路元器件。電路同時(shí)采用了低功耗設(shè)計(jì)。由于此項(xiàng)目正在進(jìn)行設(shè)計(jì)優(yōu)化階段，完整的仿真還不能達(dá)到要求，還需要對各個(gè)模塊電路進(jìn)行優(yōu)化設(shè)計(jì)。</p><p>　　Design of a Lead-Acid Battery Charging and Protecting I

20、C in Photovoltaic System</p><p>　　1.Introduction</p><p>　　Solar energy as an inexhaustible, inexhaustible source of energy more and more attention. Solar power has become popular in many countri

21、es and regions, solar lighting has also been put into use in many cities in China. As a key part of the solar lighting, battery charging and protection is particularly important. Sealed maintenance-free lead-acid battery

22、 has a sealed, leak-free, pollution-free, maintenance-free, low-cost, reliable power supply during the entire life of the battery voltage is sta</p><p>　　2.System design and considerations</p><p&g

23、t;　　The system mainly includes two parts: the battery charger module and the protection module. Of great significance for the battery as standby power use of the occasion, It can ensure that the external power supply to

24、the battery-powered, but also in the battery overcharge, over-current and an external power supply is disconnected the battery is to put the state to provide protection, the charge and protection rolled into one to make

25、the circuit to simplify and reduce valuable product waste of res</p><p>　　Maintenance-free lead-acid battery life is usually the cycle life and float life factors affecting the life of the battery charge rat

26、e, discharge rate, and float voltage. Some manufacturers said that if the overcharge protection circuit, the charging rate can be achieved even more than 2C (C is the rated capacity of the battery), battery manufacturers

27、 recommend charging rate of C/20 ~ C/3. Battery voltage and temperature, the temperature is increased by 1 °C, single cell battery voltage drops 4 </p><p>　　Based on the above, the charge on the life of

28、 maintenance-free lead-acid batteries have a significant impact, while the battery is always in good working condition, battery protection circuit must be able to detect the normal working condition of the battery and ma

29、ke the action the battery can never normal working state back to normal operation, in order to achieve the protection of the battery.</p><p>　　3.Units modular design</p><p>　　3.1The charging mod

30、ule</p><p>　　Chip, charging module block diagram shown in Figure 2. The circuitry includes current limiting, current sensing comparator, reference voltage source, under-voltage detection circuit, voltage sam

31、pling circuit and logic control circuit.</p><p>　　The module contains a stand-alone limiting amplifier and voltage control circuit, it can control off-chip drive, 20 ~30 mA, provided by the drive output curr

32、ent can directly drive an external series of adjustment tube, so as to adjust the charger output voltage and current . Voltage and current detection comparator detects the battery charge status, and control the state of

33、the input signal of the logic circuit. When the battery voltage or current is too low, the charge to start the comparator c</p><p>　　3.2 Protection Module</p><p>　　Chip block diagram of the inte

34、rnal protection circuit shown in Figure 3. The circuit includes control logic circuit, sampling circuit, overcharge detection circuit, over-discharge detection comparator, overcurrent detection comparator, load short-cir

35、cuit detection circuit, level-shifting circuit and reference circuit (BGR).</p><p>　　This module constitutes a protection circuit shown in Figure 4. Under the chip supply voltage within the normal scope of w

36、ork, and the VM pin voltage at the overcurrent detection voltage, the battery is in normal operation, the charge and discharge control of the chip high power end of the CO and DO are level, when the chip is in normal wor

37、king mode. Larger when the battery discharge current will cause voltage rise of the VM pin at the VM pin voltage at above the current detection voltage Viov, </p><p>　　4.Circuit Design</p><p>　　

38、Two charge protection module structure diagram, the circuit can be divided into four parts: the power detection circuit (under-voltage detection circuit), part of the bias circuit (sampling circuit, the reference circuit

39、 and bias circuit), the comparator (including the overcharge detection /overdischarge detection comparator, over-current detection and load short-circuit detection circuit) and the logic control part.</p><p>

40、;　　This paper describes the under-voltage detection circuit (Figure 5), and gives the bandgap reference circuit (Figure 6).</p><p>　　Battery charging, voltage stability is particularly important, undervoltag

41、e, overvoltage protection is essential, therefore integrated overvoltage, undervoltage protection circuit inside the chip, to improve power supply reliability and security. And protection circuit design should be simple,

42、 practical, here designed a CMOS process, the undervoltage protection circuit, this simple circuit structure, process and easy to implement and can be used as high-voltage power integrated circuits and othe</p>&l

43、t;p>　　Undervoltage protection circuit schematic shown in Figure 5, a total of five components: the bias circuit, reference voltage, the voltage divider circuit, differential amplifier, the output circuit. The circuit

44、supply voltage is 10V; the M0, M1, M2, R0 is the offset portion of the circuit to provide bias to the post-stage circuit, the resistance, Ro, determine the circuit's operating point, the M0, M1, M2 form a current mir

45、ror; R1 M14 is the feedback loop of the undervoltage signal; the rest of </p><p>　　5. Simulation results and analysis</p><p>　　The design of the circuit in CSMC 0.6 μm in digital CMOS process si

46、mulation and analysis of the circuit. In the overall simulation of the circuit, the main observation is that the protection module on the battery charge and discharge process by monitoring Vdd potential and Vm potential

47、leaving chip CO side and DO-side changes accordingly. The simulation waveform diagram shown in Figure 7, the overall protection module with the battery voltage changes from the usual mode conversion into overcharg</p&

48、gt;<p>　　6.Conclusion</p><p>　　Designed a set of battery charging and protection functions in one IC. This design not only can reduce the product, they can reduce the peripheral circuit components. Th