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源廣泛,可以是氫氣、甲烷、乙醇等 。 缺點(diǎn) :① 質(zhì)子交換膜成本過高 。③加氫站建設(shè)成本過高。因此很多人認(rèn)為純電動(dòng)汽車將是未來新能源汽車發(fā)展的主要方向。② 幾乎無機(jī)械噪聲,且運(yùn)行平穩(wěn) 。④結(jié)構(gòu)簡(jiǎn)單,省去很多機(jī)械裝置。② 充電設(shè)施建設(shè)不完善 能量轉(zhuǎn)化效率的比較 圖 是不同車速下燃油汽車與電動(dòng)汽車的能量輸出曲線圖。應(yīng)用混合動(dòng)力技術(shù),汽車在低速行駛時(shí)切換到電能驅(qū)動(dòng)模式,可大幅度降低能量 損耗,減少排放。 圖 燃油汽車與電動(dòng)汽車能耗曲線圖 減少耗油量的比較 表 為 同一車型利用不同技術(shù)路線而減少耗油量的比較,在對(duì)多種動(dòng)力汽車技術(shù)計(jì)算其整體擁有成本時(shí),按 照 5 年 的平均擁有期將車輛的起初成本、再銷售價(jià)值以及預(yù)計(jì)節(jié)油量納入考量范圍。 所以采用清潔能源發(fā)電配合純電動(dòng)車技術(shù)是解決機(jī)動(dòng)車環(huán)境污染問題的最佳方案。 電動(dòng)汽車的應(yīng)用缺陷和瓶頸 目前,電動(dòng)汽車技術(shù)趨于成熟,但在續(xù)駛里程、制造成本等方面還無法與傳統(tǒng)燃油汽車相比。歸納起來存在:①續(xù)駛里程有限;②蓄電池使用壽命太短;③電池價(jià)格昂貴;④充電時(shí)間和充電網(wǎng)點(diǎn)短期內(nèi)不能得到有效解決等問題。 在我國(guó),電動(dòng)汽車充電站的業(yè)務(wù)才剛剛起步,運(yùn)營(yíng)模式還沒形成,各個(gè)相關(guān)的利益群體對(duì)產(chǎn)業(yè)發(fā)展的傾向也不盡相同。 整車充電模式 整車充電模式是很多國(guó)家研究試驗(yàn)的重點(diǎn),這種模式把電池與車輛作為一個(gè)整體來考慮,其規(guī)?;l(fā)展的關(guān)鍵是能夠研制生產(chǎn)出“容量大、成本低、充電快、壽命長(zhǎng)”的電池產(chǎn)品 [7],在便捷性上滿足用戶的需求,具體又包括常規(guī)充電和快速充電兩種類型。常規(guī)蓄電池的充電方法都采用小電流的恒壓或恒流充電,一般充電時(shí)問為 5~ 8h,甚至長(zhǎng)達(dá) 10 至 20 多個(gè)小時(shí)。 這種充電方式通常適用于:設(shè)計(jì)電動(dòng)汽車的續(xù)駛里程盡可能大,需滿足車輛一天運(yùn)營(yíng)需要,僅僅利用晚問停運(yùn)時(shí)間充電。 快速充電 快速充電又稱應(yīng)急充電,是以較大電流短時(shí)間在電動(dòng)汽車停車的 20min 至 2h 內(nèi) (具體的充電時(shí)間由電動(dòng)汽車動(dòng)力電池的接收能力而定 ),為其提供短時(shí)充電服務(wù),一般充電電流為 150~400A。這種充電方式適用情況為:電動(dòng)汽車的日平均里程大于電池的續(xù)駛里程即 200km,即在車輛運(yùn)行的間隙進(jìn)行快速補(bǔ)充電,來滿足運(yùn) 營(yíng)需要;比如公交 車、出租車等車輛它們的日平均行 駛里程在 300km 左右,則還有 100km 左右的電量需要在 15 峰、平時(shí)段通過快速充電的方式進(jìn)行補(bǔ)充。 更換電池模式 更換電池模式也稱租賃電池模式,是一種把車輛與電池分開考慮的思路。可以讓用戶像“汽車加油”一樣方便地得到能源供給。電池更換站的運(yùn) 用模式可以分為以下幾點(diǎn)。電動(dòng)汽車用戶在購買“裸車”后,去電池更換站辦理相應(yīng)的“租賃手續(xù)”及交一定的租金就能使電動(dòng)汽車投入使用。用戶在電池的使用過程中不僅要交租金,每次更換電池時(shí)根據(jù)電池電量的消耗情況用戶還要向電池更換 站交納相應(yīng)的所用電費(fèi)。當(dāng)車輛進(jìn)站后,根據(jù)調(diào)度指令將車開到更換電池區(qū)準(zhǔn)確位置,準(zhǔn)備更換電池。這樣在電池串聯(lián)充電時(shí),只要有一只電池的充電電壓達(dá)到最高限制電壓,就要立即停止充電,而此時(shí)電壓較低的個(gè)體電池還處于欠充狀態(tài);反過來在電動(dòng)汽車 行駛過程中,只要有一只電池的電壓下降到最低限制電壓,就要斷開動(dòng)力電池停止放電,而此時(shí)電壓較高的個(gè)體電池容量不能充分利用 [10]。為充分利用鋰離子動(dòng)力電池的儲(chǔ)能效率,降低使用成本,充電站建設(shè)需要設(shè)置電池容量測(cè)試與充放電維護(hù)設(shè)備,當(dāng)電動(dòng)汽車動(dòng)力電池的容量明顯出現(xiàn)下降時(shí),利用該設(shè)備可以對(duì)單個(gè)電池進(jìn)行容量測(cè)試,并對(duì)容量落后的電池進(jìn)行多次的充放電操作,使其活性物質(zhì)充分激活,容量得到恢復(fù)。最主要包括以下三個(gè)方面: 整車充電中的慢速充電方式可以充分利用 低谷電力充電,電費(fèi)相對(duì)降低,但是充電時(shí)間過長(zhǎng)使車輛的使用十分不便;快速充電方式下充電時(shí)間短易于車輛的使用,但是充電費(fèi)用較高,且會(huì)大大縮短電池的使用壽命。 換電池模式屬于能源新物流模式 換電池模式有利于電池生產(chǎn)企業(yè)規(guī)?;?biāo)準(zhǔn)化生產(chǎn),有利于能源供給企業(yè)的規(guī)?;少徟c集約化管理,能夠顯著降低總運(yùn)營(yíng)成本。 整車充電中的快充大量發(fā)展將使得電網(wǎng)諧波污染問題突出 換電池模式 集中充電便于統(tǒng)一調(diào)度、管理和監(jiān)控,能夠最大程度發(fā)揮削峰填谷作用,提高電力系統(tǒng)負(fù)荷率,最大限度減少諧波污染等對(duì)電網(wǎng)的不利影響,有利于電網(wǎng)的安全穩(wěn)定運(yùn)行和電力資源的優(yōu)化利用 [12]??紤]到差異化需求和特殊情況下電能補(bǔ)給的需要,以更換電池為主、整車充電為輔的運(yùn)營(yíng)模式將成為我國(guó)電動(dòng)汽車充電站未來發(fā)展的主流模式。代用 燃料會(huì)得到迅速運(yùn)用,天然氣汽車和乙醇汽車會(huì)率先大規(guī)模投入使用, 純電動(dòng)汽車 和 燃料電池汽車將 會(huì)逐步擴(kuò)大應(yīng)用。 而純電動(dòng)汽車將是未來新能源汽車發(fā)展的最終方向。但隨著充電站以及換電站的建立,純電動(dòng)汽車技術(shù)將會(huì)逐步取代目前的任何新能源汽車技術(shù),最終發(fā)揮其在零排放、動(dòng)力性強(qiáng)、經(jīng)濟(jì)性、使用成本低方面的優(yōu)勢(shì)。 同時(shí)我也要感謝所有其他的老師,我能完成此次畢業(yè)論文,得益于所有老師這四年來對(duì)我的辛勤教育和悉心教導(dǎo)。 最后,向在百忙中抽出時(shí)間對(duì)本次畢業(yè)論文進(jìn)行評(píng)審并提出寶貴意見的各位老師表示衷心地感謝! ag an employment tribunal clai Emloyment tribunals sort out disagreements between employers and employees. You may need to make a claim to an employment tribunal if: you don39。t appealed against the disciplinary action your employer has taken against you. However, if you win your case, the tribunal may reduce any pensation awarded to you as a result of your failure to appeal. Remember that in most cases you must make an application to an employment tribunal within three months of the date when the event you are plaining about happened. If your application is received after this time limit, the tribunal will not usually accept i. If you are worried about how the time limits apply to you If you are being represented by a solicitor at the tribunal, they may ask you to sign an agreement where you pay their fee out of your pensation if you win the case. This is known as a damagesbased agreement. In England and Wales, your solicitor can39。s antiracism taskforce, is in London for the Football Association39。s Premier League match at Chelsea on Sunday. I am going to be at the match tomorrow and I have asked to meet Ya ya Toure, he told BBC Sport. For me it39。s 21 win. Michel Platini, president of European football39。s actions. CSKA said they were surprised and disappointed by Toure39。 May be back in the past, to oneself the paranoid weird belief disillusionment, these days, my mind has been very messy, in my mind constantly. Always feel oneself should go to do something, or write something. Twenty years of life trajectory deeply shallow, suddenly feel something, do ??傆X得自己似乎應(yīng)該去做點(diǎn)什么,或者寫點(diǎn)什 么。 The end of our life, and can meet many things really do? 而窮盡我們的一生,又能遇到多少事情是真正地非做不可? During my childhood, think lucky money and new clothes are necessary for New Year, but as the advance of the age, will be more and more found that those things are optional。t really grow up, it seems is not so important。t want to give vent to out your inner voice can be in the high school children of the feelings in a period, but was eventually infarction when graduation party in the throat, later again stood on the pitch he has sweat profusely, looked at his thrown a basketball hoops, suddenly found himself has already can39。 instead of letting the world soften us, we let it drive us deeper into ourselves. We try to deflect the hurt and pain by pretending it doesn’t exist, but although we can try this all we want, in the end, we can’t hide from ourselves. We need to learn to open our hearts to the potentials of life and let the world soften ,我們常常會(huì)關(guān)上心門;世界不僅沒能慰藉我們,反倒使我們更加消沉。既然如此,何不嘗試打開心門,擁抱生活中的各種可能,讓世界感化我們呢? Whenever we start to let our fears and seriousness get the best of us, we should take a step back and reevaluate our behavior. The items listed below are six ways you can open your heart more fully and ,我們應(yīng)該退后一步,重新反思自己的言行。 Whenever a painful situation arises in your life, try to embrace it instead of running away or trying to mask the hurt. When the sadness strikes, take a deep breath and lean into it. When we run away from sadness that’s unfolding in our lives, it gets stronger and more real. We take an emotion that’s fleeting and make it a solid event, instead of something that passes through ,別再逃跑或隱藏痛苦,試著擁抱它吧;當(dāng)悲傷來襲時(shí),試著深呼吸,然后直面它。屏住呼吸,生活停滯;呼出呼吸,更多新奇與經(jīng)歷又將