光伏電源逆變器的設(shè)計

摘 要

隨著傳統(tǒng)的三大化石能源日漸枯竭，綠色能源的開發(fā)和利用將會得到空前的發(fā)展，太陽能作為世界上最清潔的綠色能源之一，起并網(wǎng)發(fā)電備受世界各國普遍關(guān)注。而光伏并網(wǎng)發(fā)電系統(tǒng)的核心部件，如何可靠的高質(zhì)量地向電網(wǎng)輸送功率尤為重要，因此在可再生能源并網(wǎng)發(fā)電系統(tǒng)中起點能變換作用的逆變器成為了研究的一個熱點。為此本文仍然采用“全橋逆變+LC濾波+工頻升壓”的逆變電源設(shè)計方案。整個系統(tǒng)設(shè)計分為SPWM波形產(chǎn)生電路、H橋驅(qū)動及逆變電路、欠壓過流保護電路。
在SPWM波形產(chǎn)生環(huán)節(jié)，本文采用脈寬調(diào)制芯片SG3525的為核心。由文氏橋振蕩電路產(chǎn)生50Hz的正弦波基準(zhǔn)信號。然后經(jīng)過精密整流、放大等處理輸入到SG3525的補償信號端，從而輸出SPWM波。最后進行死區(qū)延時，輸入到驅(qū)動電路中。
在驅(qū)動電路設(shè)計環(huán)節(jié)中，本文采用兩片IR2110半橋驅(qū)動芯片構(gòu)成全橋驅(qū)動電路。輸出側(cè)逆變電路中開關(guān)管選用耐壓值高的MOSFET。然后經(jīng)過工頻變壓器進行升壓到市電，供家用電器使用。對輸入、輸出進行采樣，實時監(jiān)控是否欠壓、過流，進行保護動作。
最后，給出額定功率為500W（輸入電壓12V輸出交流220V）的單相逆變器樣機的試驗波形。

關(guān)鍵詞：光伏電源，逆變器，SPWM，SG3525，IR2110
DESIGN OF PV POWER INVERTER


ABSTRACT


In recent years, photovoltaic technology has broad application. As our country's new energy law enacted, the photovoltaic power system in our country will have a broader space for development. Inverter is an important component in PV system. Its performance has great influence on the application of photovoltaic system. Currently, the domestic pure sine wave output inverter mainly uses 50Hz transformer for raising the output voltage, this paper is still developed an inverter by using the “Full-bridge circuit + LC filter + Isolator transformer” design proposal. The whole system is divided into SPWM waveform generator circuit, H bridge driver circuit and the inverter circuit, low voltage and over-current protection circuit.
In SPWM waveform generation part, this paper uses SG3525 PWM chip core. The Wien bridge oscillation circuit generates 50Hz sine reference signal. After this signal precision rectification, amplification and other processing of the compensation signal input to the SG3525-side, so this part output the SPWM wave. Finally, the SPWM signals enter into the driving circuit after dead-time delay.
In the design of drive circuit part, using two IR2110 half-bridge driver chips constitute a full-bridge driver circuit. The output side of inverter switch circuit selects high voltage value MOSFET. Then through 50Hz transformer, boost to the mains for household appliances. Testing the samples of the input and output voltage, real-time monitoring is under-voltage, over current, protection action.
Finally, rated power for 500W (Input voltage 12V, Output communication 220V) single-phase ac inverter prototype test waveforms have been given.

KEY WORDS： PV power, Inverter, SPWM, SG3525, IR2110

目　錄

前　言 1
第1章 系統(tǒng)設(shè)計概述 3
§1.1 光伏電源逆變器的基本結(jié)構(gòu)和設(shè)計要求 3
§1.1.1 系統(tǒng)的基本結(jié)構(gòu) 3
§1.1.2 系統(tǒng)的基本設(shè)計要求 3
§1.2 系統(tǒng)電源設(shè)計 4
§1.3 逆變電路 4
§1.3.1 逆變電路的基本工作原理 4
§1.3.2 電壓型逆變電路 5
§1.4 SPWM調(diào)制技術(shù) 6
§1.4.1 理論基礎(chǔ) 6
§1.4.2 單極SPWM調(diào)制方式 7
§1.4.3 雙極性SPWM調(diào)制方式 8
第2章 SPWM調(diào)制電路 9
§2.1 SG3525芯片介紹 9
§2.1.1 功能結(jié)構(gòu) 9
§2.1.2 SG3525特性 10
§2.2 單極性SPWM調(diào)制電路 11
§2.2.1 SPWM調(diào)制電路結(jié)構(gòu) 11
§2.2.2 正弦波發(fā)生器 12
§2.2.3 精密整流電路 14
§2.2.4 誤差放大及加法電路 15
§2.2.5 SPWM調(diào)制 16
§2.2.6 時序控制電路 17
第3章 逆變電路 19
§3.1 IR2110芯片介紹 23
3.1.1功能結(jié)構(gòu) 23
§3.1.2 IR2110特性 24
§3.2 驅(qū)動電路設(shè)計 26
§3.3 輸出濾波器設(shè)計 27
§3.4 保護電路設(shè)計 29
第4章 系統(tǒng)調(diào)試 32
§4.1 信號板電路的調(diào)試 32
§4.2 信號板與H橋聯(lián)調(diào) 34
§4.3 保護電路調(diào)試 36
結(jié)　論 37
參考文獻 38
附　錄 41