外文翻譯--svc與statcom在電力系統(tǒng)中應(yīng)用的效益-免費(fèi)閱讀
【正文】 雖然 SVC 和 STATCOM 工作原理上的不同， 它們對提高電力系統(tǒng)輸電能力的影響。 在這種情況下，這兩種技術(shù)將使用遠(yuǎn)低于 ％ 的損耗（以 “ 階梯式 ”變壓器額定值）。對STATCOM轉(zhuǎn)換器中的損失占主導(dǎo)地位的橋梁。兩個不同的概念，不能在子系統(tǒng)基礎(chǔ)相比， 但很明顯，在 VSC 方案 中使用的半導(dǎo)體器件的成本下降必須顯著有利于STATCOM的總體成本。 然而，由于 STATCOM技術(shù)的發(fā)展，包括使用的非常緊湊的變頻器組件與串聯(lián)連接的半導(dǎo)體器件，和脈沖寬度調(diào)制，有小型化的明確的潛力。在一般的封裝問題似乎不妨礙 STATCOM 或 SVC 的利用率，但偶爾， STATCOM 已首選根據(jù)預(yù)期的更小的空間。在偶數(shù)倍的水平較低。該 STATCOM是一個諧波電壓源。 對于過電壓，然而， SVC電抗 不再是限制因素； 相反，由 元件的電流極限定義的。 這個分支的目的只有在欠壓條件下 進(jìn)行操作。 因此 SVC提供持續(xù)保持平穩(wěn)電壓的目的 ，試行 MSC切換。對于不對稱的評級， STATCOM需要一個互補(bǔ)的無功功率源。 發(fā)送側(cè)的電壓被控制，且兆伏 評級是指傳輸 方 。 本文的目的是解釋 SVC 和 STATCOM 在電力系統(tǒng)中的應(yīng)用的好處。 at even multiples the levels are lower. The harmonic generation decays with increasing 4 frequency. STATCOMs might also generate harmonics in the same spectra as the conventional SVCs. The magnitudes depend on converter topology and the modulation and switching frequency used. In most cases STATCOMs as well as SVCs require harmonic filters. IX. FOOTPRINT More and more frequently the footprint available for prospective STATCOMs or SVCs is restricted. The trend is, as in many other fields, more capacity on less space. Requirements for extremely tight designs, however, result in higher costs. In general the footprint issue seems not to hinder the utilization of STATCOMs or SVCs, but occasionally, STATCOM has been preferred based on anticipated smaller footprint. When paring SVCs with STATCOMs, it is tempting to assume that the latter will fit within a much smaller footprint, as the passive reactive elements (air core reactors and high voltage capacitor banks) are ―replaced‖ with semiconductor assemblies. In the authors’ opinion, this assumption however remains to be practically proved. The main reason for this is that the voltage sourced converter concepts applied in STATCOMs to date have been built with several (even as many as eight) inverter bridges in parallel. This design philosophy implies many current paths, high fault currents and plex magic interfaces between the converters and the grid. All in all, not all STATCOMs e out as downsized pared to SVCs. Also the higher losses in the STATCOM will require substantially larger cooling equipment. However, as the STATCOM technology evolves, including the use of very pact inverter assemblies with series connected semiconductor devices, and with pulse width modulation, there is a definite potential for downsizing. In the case of SVCs, the industry has a long product development where, when necessary, measures have been taken to downsize the installation. Such measures include elevated design of apparatuses, stacking of ponents (reactors and capacitors), vertical orientation of busbars and use of nonmagic material in nearby structures. In a few extreme cases iron core reactors have been utilized in order to allow installation in very tight premises. In addition the development of much higher power density in high power thyristors and capacitors contributes to physically smaller SVCs. X. LIFE CYCLE OR EVALUATED COSTS It is the authors’ experience that the investment cost of SVCs is today substantially lower than of parable STATCOMs. As STATCOMs provides improved performance, it will be the choice in the cases where this can be justified, such as flicker pensation at large electrical arc furnaces or in bination with active power transfer (backtoback DC schemes). The two different concepts cannot be pared on a subsystem basis but it is clear 5 that the cost of the turnoff semiconductor devices used in VSC schemes must e down significantly for the overall cost to favor the STATCOM. In other industries using high power semiconductors, like electrical traction and drives, the mainstream transition to VSC technology is since long p
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