外文翻譯--基于68hc908mr16單片機(jī)的光伏正弦波逆變電源

1、<p>　　Photovoltaic Power Pupply Pine Pave Inverter Based On 68HC908MR16 MCU</p><p>　　Introduction </p><p>　　With the growing energy crisis and increase the environmental awareness of mankin

2、d, the development and utilization of new energy is receiving increasing attention. And solar energy as an inexhaustible supply of highly efficient non-polluting energy has more people of all ages. In this paper, the pho

3、tovoltaic power system is sinusoidal inverter suitable for a household, especially for electricity without electricity in remote areas of the western region of a power system users, as China's wester</p><p

4、>　　2 Structure and principle of the inverter system </p><p>　　2.1 The basic structure of the system </p><p>　　First of all, by the solar array to the battery charging circuit in order to get

5、a basic stability of the DC voltage, and then by the inverter circuit will be high-frequency alternating current into direct current reverse, and finally by the frequency step-up transformer and filter circuit filtering

6、into 50Hz, 220V sinusoidal AC voltage. Control of the whole system is completed by a single-chip MR16. The core part of the formation of SPWM wave and the output AC voltage according to the feedback </p><p>

7、　　2.2 Single-chip on the MR16 </p><p>　　68HC908MR16 single chip is a low-cost, high-performance single-chip 8. It has 32k bytes of rewritable flash memory-chip FLASH, with 768 bytes of RAM, this system compl

8、etely enough; with a dedicated motor control for 6-channel PWM output PWMMC modules, suitable for in single-phase, three-phase inverter, at the same time the module was also devoted to the protection Fault FAULT pin 4, w

9、hen the fault does not occur in the case of interruption caused by the rapid blockade of the PWM output to achiev</p><p>　　2.3 Inverter Main Circuit </p><p>　　Switching device is appropriate for

10、 low-power devices, with switching speed, high frequency characteristics of the power MOSFET. Switch gate drive signal from the single-chip MR16 wave generated by the SPWM signal driver circuit. Full-bridge inverter SPWM

11、 output for high-frequency wave, the step-up transformer and filter immediately be 220V, 50Hz standard AC voltage sinusoidal. </p><p>　　2.4 SPWM wave formation </p><p>　　68HC908MR16 with a speci

12、al single-chip motor control can be used to work in three pairs of complementary mode or standalone mode, including 6-channel PWM output module PWMMC. Initialization of the system in its work in three pairs of complement

13、ary patterns in the same bridge that the two PWM signal arm is complementary, in the initialization of dollars to write a value to the PMOD (H: L) in order to determine the carrier frequency that is switching frequency.

14、Real-time wave PWM pulse width calcu</p><p>　　Carrier cycle = 1/10k = PMOD (H: L) × (1/8M) × 2 </p><p>　　Therefore, the system must be initialized PMOD (H: L) = $ 0190 (Note: $ for the

15、 MR16 in hexadecimal notation) </p><p>　　2.5 System control structure </p><p>　　The system through the digital PI regulator to control the realization of regulators. The control system block dia

16、gram shown in figure 3. AC voltage feedback signal from the AD sample, in order to ensure accuracy, the system uses sampling voltage transformer. Just start to set output voltage from the soft-start, soft-start is genera

17、ted at startup in order to avoid large peak current, soft-start the use of successive incremental increases to a voltage required for the method, after the soft-start</p><p>　　3 Serial Communication </p&g

18、t;<p>　　In order to enhance the system's ability to adapt to different environments, it is necessary to monitor and control system to monitor and modify the parameters of regulation, this system uses a serial

19、communication technology keyboard monitoring system with the outside world to communicate. Procedures on the use of inquiry methods to the outside world periodically send test data, test data including the solar cell vol

20、tage, charge current, battery voltage, DC current, output voltage, output curre</p><p>　　4 System software design </p><p>　　The modular design of system software, including the initialization mo

21、dule, the protection module, regulator modules, communication modules, such as interruption of program modules, in addition to disruption of modules outside the main program on the remaining modules, which will </p>

22、;<p>　　Completion of system initialization main module initialization, the variable unit, given the initial value of the register unit. </p><p>　　Protection module in accordance with voltage and curre

23、nt sample values to determine fault and the fault occurs in the PWM output of the blockade. Protection, including under-voltage battery, battery over-voltage, system overload, overheating protection, including battery vo

24、ltage, over-voltage protection can be achieved since the restoration, that is, the battery voltage is detected and returned to normal, the system re-soft-start and resume normal work. Overcurrent protection as a result o

25、f the </p><p>　　Regulator module to complete the system of the PI regulator output voltage regulation, so that the output voltage stabilized at 220V, while soft-start on them also. The entrance to the output

26、 parameters for the soft-start exports to the disruption module M parameters involved in the calculation of PWM pulse width. Through real-time adjustment of the value of the parameter value can be changed so that the out

27、put pulse width given to follow. </p><p>　　Interruption of program modules to complete the issue of SPWM waveform, AC voltage, AC current parameters of the sample. Interruption of the entrance parameters of

28、PI regulator for the output parameter M, the parameters involved in the calculation of pulse width that is PVALX (H: L) values calculated, thus changing the duty cycle which regulates the output voltage. 2 in accordance

29、with the rules of SPWM sampling methods, combined with the initialization of PWMMC set formula for calculating real-</p><p>　　Is a half cycle: </p><p>　　PVALX (H: L) = PMOD (H: L) / 2 + M ×

30、 SIN (PTR) </p><p>　　Negative half-cycle: </p><p>　　PVALX (H: L) = PMOD (H: L) / 2-M × SIN (PTR) </p><p>　　One PTR pointer to sine table, SIN (PTR) for the corresponding sine v

31、alue of the pointer PTR. </p><p>　　Prototype made in accordance with the above thinking, the last to be relatively standard 220V, 50Hz sinusoidal voltage, soft-start is also very stable, its frequency error

32、≤ 0.1%, the output voltage error of ≤ 0.5%. As a result of the carrier frequency of 10kHz, in the transformer primary side to be 20kHz high-frequency signals without noise. Under the above-mentioned control can ensure th

33、e system load or a sudden reduction in load to maintain output voltage stability quickly. Keyboard and monit</p><p>　　基于68HC908MR16單片機(jī)的光伏正弦波逆變電源</p><p><b>　　引言</b></p><p&g

34、t;　　隨著能源危機(jī)的日益加劇和人類環(huán)保意識的提高，新能源的開發(fā)利用越來越受到人們的重視。而太陽能作為取之不盡用之不竭的高效無污染的能源近來更受人們的青睞。本文介紹的光伏正弦逆變電源系統(tǒng)正是一種適于戶用的、特別適于無電少電的西部邊遠(yuǎn)地區(qū)用戶的一種電源系統(tǒng)，隨著我國西部大開發(fā)的進(jìn)行其市場前景必將越來越廣闊 。</p><p>　　2　逆變系統(tǒng)結(jié)構(gòu)及原理</p><p>　　2.1　系統(tǒng)基本結(jié)

35、構(gòu)</p><p>　　首先太陽電池陣列經(jīng)充電電路向蓄電池充電，從而得到一個基本穩(wěn)定的直流電壓，再經(jīng)逆變電路將直流電逆變成高頻交流電，最后經(jīng)工頻變壓器升壓和濾波電路濾波變成50Hz、220V正弦交流電壓。整個系統(tǒng)的控制都是由MR16單片機(jī)完成的。其核心部分 為SPWM波的形成及根據(jù)輸出交流電壓采樣形成反饋組成的數(shù)字式PI調(diào)節(jié)器部分。</p><p>　　2.2　關(guān)于MR16單片機(jī)</

36、p><p>　　68HC908MR16單片機(jī)是一種低成本、高性能的八位單片機(jī)。它具有32k字節(jié)的可擦寫的片內(nèi)閃速存儲器FLASH，具有768字節(jié)的RAM，對于本系統(tǒng)來說完全夠用；具有一個專門用于電機(jī)控制的6路PWM輸出 的PWMMC模塊，適合于單相、三相逆變，同時該模塊還有專門用于故障保護(hù)的4路FAULT引腳，當(dāng)故障發(fā)生時可在不引起中斷的情況下快速封鎖PWM輸出達(dá)到保護(hù)的目的；具有可選擇外部晶振時鐘或內(nèi)部鎖相環(huán)時鐘的

37、時鐘發(fā)生器模塊，本系統(tǒng)選擇的內(nèi)部鎖相環(huán)時鐘能產(chǎn)生精確的8MHz的內(nèi)部總線頻率，從而保證了系統(tǒng)的頻率精度；具有可編程的AD時鐘,AD轉(zhuǎn)換時間最快只需2μs，能最大程度地減少中斷程序的執(zhí)行時間；具有SCI串行通信接口，可工作于全雙工或半雙工模式，在本系統(tǒng)中能夠可靠地完成與外界鍵盤監(jiān)控系統(tǒng)的串行通信 。</p><p><b>　　2.3　逆變主電路</b></p><p>

38、;　　開關(guān)器件采用適合于小功率裝置、具有開關(guān)速度快、工作頻率高等特性的功 率MOSFET。開關(guān)管的柵極驅(qū)動信號來源于MR16單片機(jī)產(chǎn)生的SPWM波經(jīng)驅(qū)動電路后的信號。全橋逆變的輸出為高頻SPWM波，經(jīng)變壓器升壓及濾波后即得到220V、50Hz的標(biāo)準(zhǔn)正弦交流電壓。</p><p>　　2.4　SPWM波的形成</p><p>　　68HC908MR16單片機(jī)具有一個專門用于電機(jī)控制的可工作于

39、3對互補(bǔ)模式或獨(dú)立模式的包括6路PWM輸出 的PWMMC模塊。在本系統(tǒng)中初始化使其工作于3對互補(bǔ)模式即同一橋臂2個PWM信號是為互補(bǔ)的，在初始化中寫一計數(shù)值到PMOD(H:L)中以決定載波頻率即開關(guān)頻率。PWM波的實時脈寬計算是由中斷程序完成的，每 次PWMMC模塊中的PCTN(H:L)計數(shù)器計數(shù)到PMOD(H:L)中的值時就引起中斷。預(yù)先將0～360°的正弦值制成表格存于FLASH某一區(qū)域中，每次中斷時從中取一正弦值，經(jīng)過一

40、定計算后得一數(shù)值，將其送 入PVALX(H:L)寄存器中，單片機(jī)將PVALX(H:L)中的值與PMOD(H:L)中的值比較后自動生成SPWM信號并由PWM引腳發(fā)出。為了防止同一橋臂兩個管子同時導(dǎo)通的現(xiàn)象發(fā)生，在無信號發(fā)生 器DEADTIME中的寄存器DEADTM中寫入一數(shù)值以確定死區(qū)時間。本系統(tǒng)設(shè)計死區(qū)時間為2.5μs，載波頻率為10kHz，制成包括200個放大的正弦值的正弦表。PWMMC模塊還有4路故障保護(hù)端口FAULT1～FAULT

41、4，當(dāng)端口為高電平時 ，PWMMC就能根據(jù)初始化設(shè)定來封鎖相應(yīng)的PW</p><p>　　載波周期=1/10k=PMOD(H:L)×(1/8M)×2</p><p>　　所以本系統(tǒng)須初始化PMOD(H:L)=＄0190(注：＄為MR16中十六進(jìn)制符號)</p><p>　　2.5　系統(tǒng)的控制結(jié)構(gòu)</p><p>　　本系統(tǒng)

42、通過數(shù)字式PI調(diào)節(jié)器實現(xiàn)穩(wěn)壓控制。系統(tǒng)的控制框圖如圖3所示。反饋信號來自交流電壓的AD采樣，為了保證精度，本系統(tǒng)利用變壓器進(jìn)行電壓采樣。剛啟動時給定電壓取自軟啟動輸出，軟啟動是為了避免啟動時產(chǎn)生大的峰值電流，軟啟動采用逐次加1遞增到所需電壓的方法，軟啟動結(jié)束后給定電壓就是對應(yīng)于220V電壓的數(shù)值。為了加強(qiáng)快速性，本系統(tǒng)采用前饋控制與反饋控制相結(jié)合的控制方式。為了增強(qiáng)系統(tǒng)的動態(tài)輸出特性，本系統(tǒng)采用根據(jù)偏差大小改變比例系數(shù)和積分系數(shù)的模糊控

43、制方法，當(dāng)偏差較大時，比例系數(shù)和積分系數(shù)也較大，當(dāng)偏差較小時比例系數(shù)和積分系數(shù)也較小，從而大大減少了超調(diào)量，很容易使系統(tǒng)穩(wěn)定，完全消除了積分飽和現(xiàn)象，也增強(qiáng)了系統(tǒng)的適應(yīng)能力。</p><p><b>　　3　串行通信</b></p><p>　　為了增強(qiáng)系統(tǒng)適應(yīng)不同環(huán)境的能力，有必要對系統(tǒng)進(jìn)行監(jiān)控監(jiān)測及對參數(shù)進(jìn)行修改調(diào)節(jié)，本系統(tǒng)采用串行通信技術(shù)同外界鍵盤監(jiān)控系統(tǒng)進(jìn)行通

44、信。程序上采用查詢方式，周期性地向外界發(fā)送檢測的數(shù)據(jù)，檢測的數(shù)據(jù)包括太陽電池電壓、充電電流、蓄電池電壓、直流側(cè)電流、輸出電壓、輸出電流、散熱器溫度等，當(dāng)發(fā)生故障時優(yōu)先發(fā)送故障信號，當(dāng)需要修改參數(shù)時就接收數(shù)據(jù)并修改相應(yīng)參數(shù)，并使用校驗和校驗的方法檢驗數(shù)據(jù)通信的準(zhǔn)確性。硬件采用MAXIM公司的MAX485作為接口芯片使其工作于半雙工模式，同時本系統(tǒng)采用光耦隔離的辦法以增強(qiáng)系統(tǒng)抗干擾能力，提高可靠性 。</p><p>

45、;<b>　　4　系統(tǒng)的軟件設(shè)計</b></p><p>　　本系統(tǒng)軟件采用模塊化設(shè)計，包括初始化模塊、保護(hù)模塊、調(diào)節(jié)器模塊、通信模塊、中斷程序模塊等，除中斷模塊外其余模塊都放在主程序中進(jìn)行， </p><p>　　初始化模塊主要完成系統(tǒng)的初始化、各變量單元、各寄存器單元賦初值。</p><p>　　保護(hù)模塊根據(jù)電壓電流采樣值進(jìn)行故障判斷，并在

46、故障發(fā)生時封鎖PWM的輸出。保護(hù)包括蓄電池欠壓、蓄電池過壓、系統(tǒng)過載、過熱保護(hù)等，其中蓄電池欠壓、過壓保護(hù)能夠?qū)崿F(xiàn)自恢復(fù)，即在檢測到蓄電池電壓又恢復(fù)正常時，系統(tǒng)重新軟啟動并恢復(fù)正常工作。過流保護(hù)由于需要快速反應(yīng)故采用硬件保護(hù)，當(dāng)過流發(fā)生時就立即封鎖全 部PWM輸出，也立即封鎖全部驅(qū)動電路，只有重新復(fù)位時才能恢復(fù)工作，軟件可判斷出是否發(fā)生過流保護(hù)。</p><p>　　調(diào)節(jié)器模塊完成對系統(tǒng)輸出電壓穩(wěn)壓的PI調(diào)節(jié)，使

47、輸出電壓穩(wěn)定在220V，同時軟啟動也放在其中。其入口參數(shù)為軟啟動輸出，出口參數(shù)M送到中斷模塊中參 與PWM脈寬的計算。通過實時調(diào)節(jié)該參數(shù)的值就能改變脈寬值從而使輸出跟隨給定。</p><p>　　中斷程序模塊完成SPWM波形的發(fā)出、交流電壓、交流電流參數(shù)的采樣。中斷的入口參數(shù)為PI調(diào)節(jié)器的輸出參數(shù)M，該參數(shù)參與脈寬的計算 即PVALX(H:L)值的計算，從而改變了占空比也即調(diào)節(jié)了輸出電壓。按照SPWM的規(guī)則2采樣

48、的方法，結(jié)合初始化中對PWMMC的設(shè)定得脈寬的實時計算公式為</p><p><b>　　正半周期：</b></p><p>　　PVALX(H:L)=PMOD(H:L)/2＋M×SIN(PTR)</p><p><b>　　負(fù)半周期：</b></p><p>　　PVALX(H:L)=P

49、MOD(H:L)/2－M×SIN(PTR)</p><p>　　其中PTR為正弦表指針，SIN(PTR)為對應(yīng)PTR指針的正弦值。</p><p>　　按照以上思想制成樣機(jī)，最后能得到比較標(biāo)準(zhǔn)的220V、50Hz正弦電壓，軟啟動也很平穩(wěn)，其頻率誤差≤0.1％,輸出電壓誤差≤0.5％。由于采用10kHz的載波頻率，在變壓器原邊得到20kHz高頻信號，無噪聲。在上述控制方式下，能保證