【正文】 一次系統(tǒng) 設(shè)計(jì)。以一回路與本所連接。電氣主接線設(shè)計(jì)是依據(jù)變電所的最高電壓等級(jí)和變電所的性質(zhì)，選擇出某種與變電所在系統(tǒng)中的地位和作用相適應(yīng)的接線方式。擴(kuò)建時(shí)需向兩個(gè)方向均衡擴(kuò)建。高壓側(cè)斷路器檢修時(shí)，變壓器較長(zhǎng)時(shí)期停運(yùn)。當(dāng)個(gè)別回路需要單獨(dú)進(jìn)行試驗(yàn)時(shí)，可將該回路分開(kāi)，單獨(dú)接至一組母線上。占地面積較大。雖然方案Ⅰ可靠性、靈活性不如方案Ⅱ，但其具有良好的經(jīng)濟(jì)性。當(dāng)一臺(tái)停運(yùn)時(shí)，另一臺(tái)則承擔(dān) 70%為 42KVA。 適用情況 以及優(yōu)點(diǎn) 1）發(fā)電廠的廠用電和變電所的所用電。 5） BZT 裝置動(dòng)作過(guò)程應(yīng)使負(fù)荷中斷供電的時(shí)間盡可能短。 第 5 章 短路電流計(jì)算 在電力系統(tǒng)運(yùn)行中都必須考慮到可能發(fā)生的各種故障和不正常運(yùn)行狀態(tài)，最常見(jiàn)同時(shí)也是最危險(xiǎn)的故障是發(fā)生各種型式的短路，因?yàn)樗鼈儠?huì)遭到破壞對(duì)用戶(hù)的正常供電和電氣設(shè)備的正常運(yùn)行。 變電所母線保護(hù)配置 110KV、 35KV 線路保護(hù)部分： 1)距離保護(hù) 2)零序過(guò)電流保護(hù) 3)自動(dòng)重合閘 4)過(guò)電壓保護(hù) 10KV 線路保護(hù)： 1)10kV 線路保護(hù)：采用微機(jī)保護(hù)裝置，實(shí)現(xiàn)電流速斷及過(guò)流保護(hù)、實(shí)現(xiàn)三相一次重合閘。 變壓器的零序過(guò)流保護(hù) 對(duì)于大接地電流的電力變壓器，一般應(yīng)裝設(shè)零序電流保護(hù)，用作變壓器主保護(hù)的后備保護(hù)和相鄰元件接地短路的后備保護(hù)，一般變電所內(nèi)只有部分變壓器中性點(diǎn)接地運(yùn)行，因此，每臺(tái)變壓器上需要裝設(shè)兩套零序電流保護(hù)，一套用于中性點(diǎn)接地運(yùn)行方式，另一套用于中性點(diǎn)不接地運(yùn)行方式 第 6 章 防雷接地 變電所是電力系統(tǒng)的中心環(huán)節(jié)，是電能供應(yīng)的來(lái)源，一旦發(fā)生雷擊事故，將造成大面積的停電，而且電氣設(shè)備的內(nèi)絕緣會(huì)受到損壞，絕大多數(shù)不能自行恢復(fù)會(huì)嚴(yán)重影響國(guó)民經(jīng)濟(jì)和人民生活，因此，要采取有效的防雷措施，保證電氣設(shè)備的安全運(yùn)行。 4） 220KV 及以下變壓器到避雷器的電氣距離超過(guò)允許值時(shí)，應(yīng)在變壓器附近增設(shè)一組避雷器。本設(shè)計(jì)中采用的是在進(jìn)線進(jìn)線 1～ 2km 范圍內(nèi)裝設(shè)避雷器。 接地網(wǎng)型式選擇及優(yōu)劣分析 220kv 及以下變電站地網(wǎng)網(wǎng)格布置采用長(zhǎng)孔網(wǎng)或方孔網(wǎng)，接地帶布置按經(jīng)驗(yàn)設(shè)計(jì)，水平接地帶間距通常為 5m8m。如果用打深井來(lái)裝設(shè)長(zhǎng)接地極，則施工費(fèi)很高，如利用地質(zhì)勘察鉆孔埋設(shè)長(zhǎng)接地極，施工費(fèi)將大大節(jié)省。這也是降低接地電阻的有效措施。80s. We sat on the back of pickup trucks for hours. The sky was blue, and we couldn39。s Liaoning province, decades ago. The solider gave the old man a handmade saddle when they bid farewell. The story inspired Nasun to write Carved Saddle, a song that later became one of his most popular numbers. Now, every year, Nasun recruits young singers and dancers for the troupe. The troupe has also designed a new repertoire, which is mostly based on the daily lives of Mongolian people, especially the lives of nomadic families, and has bined contemporary musical elements with folk songs of the region. Haimu, a 25yearold khoomei (a local variant of overtone singing) singer, joined the troupe three years ago. Along with a sixmember band, he performs fast songs and soft ones that he writes－ all while playing the horsehead fiddle.Although I learned the piano since childhood and grew up listening to various kinds of music, to me, the folk music of Inner Mongolia is the root, he says. Performing in remote villages is pleasant. I feel at home on the boundless grasslands, and the warm people there make me feel fulfilled. The first round of spring auction season in Beijing ended last week, but it failed to create much spring in the art market. Although two pieces of Chinese painting fetched more than 100 million yuan, the decline in trading volume and sale rate showed a downturn this year. In the ―Grand View: Chinese Painting Highlight‖ session at China Guardian 2021 spring auctions, Pan Tianshou’s representative work Eagle, Rock and Flora hit a record auction price of 279 million yuan, while Li Keran’s masterwork Jinggang Mountain fetched million yuan, an unexpected high in recent years. However, the trading volume fells to billion yuan from billion yuan in the same period the year before. The Huangchen 2021 Spring Auctions, which recorded million yuan in total sales, experienced the same. The section number went down to 5 from 12 pared to last year. According to expert Shao Jianwu, the art market did not attract much excitement this year due to the booming stock market and the persistent problems of fery and fake deals. The two pieces of Chinese painting notched up high price this spring due to their own value not due to a revival in the market. The successful transaction of two works with a hammer price of more than 100 million yuan once again confirms that valuable and rare works of high quality always earn the longlasting high price. Chinese painting and calligraphy is still the pillar of the market. However, the overall sales rate has dropped slightly, which reflects the demand for the ordinary auction goods has weakened,‖ said the president of China Guardian’s Hu Yanyan. Besides, the entry of new buyers also makes certain changes to the direction of purchasing. In a word, the overall market trend is very unpredictable. Although China Guardian 2021 Spring Auctions has achieved remarkable results, it does not mean that the market has walked out of the predicament. We still have to wait for the big economic boom to invigorate the art market.‖ Even so, the hot pursuit of some special items appeared this spring. A special session of China Guardian Spring Auctions titled ―Fine Gilt—Bronze Buddhist Images‖ achieved a great deal with total sales volume of million yuan and 92 percent sale rate. The 5th Shamar Rinpoche Statue from 1617th century of Tibet was sold for million yuan. The Beijing Chengxuan Auctions featured almost 2,800 items of coins and stamps in three sessions with good sale rate. The Huachen Auctions also set a special session of photographs under the condition of largescale decline of auction sessions. There was a palpable dull thud of disappointment that acpanied the return of the imperial entourage of Zhen Huan to her homeland. It followed a couple years of hushed excitement as Chinese fans were fed tidbits about their proud concubine who was supposed to conquer the high ground of the North American market. Zhen Huan is, of course, the title character of The Legend of Zhen Huan, a 2021 television series that swept China off its feet and later took other Asian countries by storm. Two years ago, it was reported that HBO, a premium cable service headquartered in the United States, was going to air it in North America after some modification. Now, a condensed version that provides English subtitles but no dubbing has finally been made available on Netflix for online streaming. This version, highly anticipated as a milestone in