【正文】 源資源卻遠(yuǎn)離需求中心，76%的煤炭集中在北部和西北部、80%的水能資源集中在西南部，陸地風(fēng)能和太陽能等新能源也大量分布在西北部，供需相距800－3000公里，現(xiàn)有500千伏輸電系統(tǒng)面臨著遠(yuǎn)距離、大容量輸送能力不足，走廊資源緊缺等瓶頸制約，亟待升級至1000千伏等級。到2006年8月國家發(fā)改委批準(zhǔn)建設(shè)晉東南至荊門1000千伏特高壓交流試驗(yàn)示范工程時(shí)，“發(fā)展特高壓輸電，在技術(shù)上沒有難以克服的障礙，在工程上已具備實(shí)際應(yīng)用的條件”。 項(xiàng)目帶動(dòng)我國輸變電裝備制造業(yè)實(shí)現(xiàn)全面升級。劉振亞介紹，項(xiàng)目成果除應(yīng)用于已建成投運(yùn)的特高壓交流試驗(yàn)示范工程及其擴(kuò)建工程，還在在建的安徽“兩淮”煤電基地送上海特高壓交流工程中得到應(yīng)用。以特高壓交流試驗(yàn)示范工程為起點(diǎn)，國家電網(wǎng)公司正“整體、快速”推進(jìn)特高壓電網(wǎng)建設(shè)。在世界上首次實(shí)現(xiàn)了復(fù)雜環(huán)境下特高壓系統(tǒng)外絕緣優(yōu)化配置。隨著電網(wǎng)區(qū)域的擴(kuò)大，電能的傳輸容量和傳輸距離也不斷增大。4）減少線路的功率損耗,kV輸電比1200特高壓直流輸電優(yōu)點(diǎn)1）不存在系統(tǒng)穩(wěn)定問題，可實(shí)現(xiàn)電網(wǎng)的非同期互聯(lián)。直流輸電通過可控硅換流器能快速調(diào)整有功功率，實(shí)現(xiàn)“潮流翻轉(zhuǎn)”（功率流動(dòng)方向的改變），在正常時(shí)能保證穩(wěn)定輸出，在事故情況下，可實(shí)現(xiàn)健全系統(tǒng)對故障系統(tǒng)的緊急支援，也能實(shí)現(xiàn)振蕩阻尼和次同步振蕩的抑制。m，而前者輸送容量約為后者2倍，即直流傳輸效率約為交流2倍。而特高壓直流線路存在極性問題，正極性導(dǎo)線比負(fù)極性導(dǎo)線更易遭受雷害。ｈ．由于特高壓直流絕緣子染污速度快、電氣強(qiáng)度下降多、腐蝕問題嚴(yán)重，因此，對于同一絕緣子，在特高壓直流情況下的污閃問題會(huì)比特高壓交流情況更嚴(yán)重。s largest virgin forest, and known for its spring and ecological environment, Arxan is marveled at by many tourists as the purest land on earth. Festival. In this day, girls will throw a sewing needle into a bowl full of water on the night of Qixi as a test of embroidery skills. If the needle floats on top of the water instead of sinking, it proves the girl is a skilled embroiders. Single women also pray for finding a good husband in the future. And the newly married women pray to bee pregnant quickly. Tradition transformed The love story of Niulang and Zhinu, and the Qixi Festival have been handed down for generations. Yet these ancient traditions and customs are slowly dying out. Many modern Chinese, particularly youngsters, seem to know more about St Valentine39。rains heavily on Saturday night, some elderly Chinese will say it is because Zhinu, or the Weaving Maid, is crying on the day she met her husband Niulang, or the Cowherd, on the Milky Way. Most Chinese remember being told this romantic tragedy when they were children on Qixi, or the Seventh Night Festival, which falls on the seventh day of the seventh lunar month, which is usually in early August. This year it falls on Saturday, August 2. Folklore Story As the story goes, once there was a cowherd, Niulang, who lived with his elder brother and sisterinlaw. But she disliked and abused him, and the boy was forced to leave home with only an old cow for pany. The cow, however, was a former god who had violated imperial rules and was sent to earth in bovine form. One day the cow led Niulang to a lake where fairies took a bath on earth. Among them was Zhinu, the most beautiful fairy and a skilled seamstress. The two fell in love at first sight and were soon married. They had a son and daughter and their happy life was held up as an example for hundreds of years in China. Yet in the eyes of the Jade Emperor, the Supreme Deity in Taoism, marriage between a mortal and fairy was strictly forbidden. He ordered the heaven troop to catch Zhinu back. Niulang grew desperate when he discovered Zhinu had been taken back to heaven. Driven by Niulang39。wait in the line for one hour to get a ticket, and another two hours at the site, to only see a tiny bit of the place due to the crowds. Last year, 428 million tourists traveled in China over the weeklong holiday in October. Traveling during this period is a matter that needs thorough preparation. If you are short on time to plan the uping Golden Week it may not be a bad idea to avoid some of the most crowded places for now. There is always a place so fascinating that everyone yearns for. Arxan is a place like this. The beauty of Arxan is everlasting regardless of the changing of four seasons. Bestowed by nature, its spectacular seasonal landscape and mountains are just beyond word. Arxan is a crucial destination for the remended travelling route, China Inner Mongolia Arxan — Hailar — Manzhouli. It is also the joint of the four prairies across the SinoMongolian border, where people gravitate towards the exotic atmosphere mixed with Chinese, Russian, and Mongolia elements. As a historic site for the Yitian Battle, Arxan still embodies the spirit of Genghis Khan. Walking into Arxan, you will be amazed by a kaleidoscope of gorgeous colors all the year round the Spring azaleas blooming red in the snow, the Summer sea wavering blue in the breeze, the Autumn leaves painted in yellow covering volcanic traces, and the Winter woods shining white on the vast alpine snowscape. Hinggan League Arxan city is situated in the far eastern area of Inner Mongolia Autonomous Region. Its full name Haren Arxan means hot holy water in the Mongolian language. Arxan is a tourism city in th