【正文】 在這種模式下， 勵(lì)磁系統(tǒng)能夠通過提供 或吸收無(wú)功功率維持電力系統(tǒng)電壓在 允許范圍 內(nèi)， 必 要時(shí) ， 也 能夠通過 增加同步轉(zhuǎn)矩 來(lái)維 持發(fā)電機(jī)與電力系統(tǒng) 的穩(wěn)定 。輔助控制 包括以下幾個(gè)方面： 最大 /最小勵(lì)磁級(jí)別限制（有機(jī)電致發(fā)光 /梅爾分別是，這些限制可能是十分之一依賴 ） ； 定子電流限制，以防止定子 過 熱超負(fù)荷 ； 伏特每赫茲的限制，以防止 由于潮流過剩導(dǎo)致 設(shè)備損壞 ； 機(jī) 端電壓限制，以防止由于過量介質(zhì)應(yīng)力設(shè)備損壞 ； 線下降的補(bǔ)償， 對(duì)于 系統(tǒng)電壓凹陷以增加發(fā)電機(jī)的反應(yīng) ； 無(wú)功控制發(fā)電機(jī)試圖規(guī)范相同參數(shù) ； 電力系統(tǒng)穩(wěn)定，從而抑制低頻 振動(dòng) ； 振蕩 上限 (UEL），以保護(hù)對(duì)發(fā)電機(jī)定子端部繞組 發(fā)熱 ，同運(yùn)行于 振蕩 模式 [15]。這些輔助控制，可確保即使根據(jù)自 動(dòng)調(diào)節(jié)的一個(gè)主要參數(shù)，發(fā)電機(jī) 總是能運(yùn)行 在其能力范圍內(nèi)。勵(lì)磁系統(tǒng)也可 運(yùn)行 在 沒有自動(dòng)調(diào)節(jié)的情況下 手動(dòng)控制 。如果發(fā)電機(jī) 脫離電力系統(tǒng)運(yùn)行 ，并沒有任何其他無(wú)功源控制 機(jī) 端電壓， 增加 勵(lì)磁功率會(huì)增加發(fā)電機(jī)的 機(jī) 端電壓，反之亦然。如果 機(jī) 端電壓是 穩(wěn)定的，增加勵(lì)磁 電流 將增加同步 機(jī)械 轉(zhuǎn)矩，并增加了無(wú)功功率的輸出。 A：勵(lì)磁控制 ： 發(fā)電機(jī) 的 勵(lì)磁系統(tǒng)提供能源 建立 磁場(chǎng) 從而 使發(fā)電機(jī)與電力系統(tǒng) 保持同步 。系統(tǒng)的保護(hù)，以及其他控制 措施對(duì)系統(tǒng)的平衡 是必要的，以避免系統(tǒng)崩潰。 這 需要采取 控制 措施 ，例如按頻率降低自動(dòng)減負(fù)荷 ，適當(dāng)?shù)鼗謴?fù)系統(tǒng)頻率和電壓在不同的 電壓等級(jí) 。繼電器的誤動(dòng)可能會(huì)導(dǎo)致不必要的動(dòng)作或系統(tǒng)的大干擾。 即使成功的排除了故障，有時(shí)候由于線路過負(fù)荷、無(wú)功缺額、不適合的繼電裝置仍能導(dǎo)致繼電器的誤動(dòng)。成功排除故障后，系統(tǒng)重新進(jìn)入一個(gè)新的穩(wěn)定的運(yùn)行狀態(tài)。 這些要求在故障和其他干擾下并不能得到滿足。高架線是組任何電力系統(tǒng)的重要組成部分而瞬時(shí)性故障是由于種種原因而發(fā)生的。 很多系統(tǒng)干擾可以歸因于運(yùn)行極限和在生產(chǎn)、輸電的少量冗余及配電能力。大干擾是由于電力系統(tǒng)的規(guī)模和復(fù)雜性而向系統(tǒng)設(shè)備挑戰(zhàn)的情況。 Ⅱ .電力系統(tǒng)干擾 : 電力系統(tǒng)干擾就是指系統(tǒng)產(chǎn)生不正常運(yùn)行狀態(tài)和系統(tǒng)從正常運(yùn)行進(jìn)入緊急狀態(tài)的情況。 過去電力系統(tǒng)故障的簡(jiǎn)潔描述就是發(fā)電機(jī)勵(lì)磁、渦輪機(jī)、調(diào)速器及電力系統(tǒng)控制也包括在內(nèi)。 從過去發(fā)生的主要事故中我們知道在發(fā)生故障的瞬間與發(fā)電機(jī)有關(guān)的保護(hù)有可能會(huì)動(dòng)作。 專業(yè)術(shù)語(yǔ)索引 : 交流發(fā)電機(jī)勵(lì)磁、交流發(fā)電機(jī)保護(hù)、調(diào)速器、電力系統(tǒng)控制、 渦輪機(jī) Ⅰ .說(shuō)明 : 所有電力系統(tǒng)每時(shí)每刻都會(huì)受到由于故障或主要負(fù)荷的開斷造成的瞬時(shí)性干擾。These system controls are often called special protection schemes or remedial action schemes. It is expected that generator protective devices will coordinate with the generator capability to withstand abnormal operating conditions. However, it is important that such protective devices also coordinate with the power system special protection schemes, which are intended to limit the abnormal operating conditions to within the generator capabilities. Some mon special protection schemes are noted below. Lender frequency load shedding is applied to prevent extended system operation at low frequency. The possibility of such operation arises when there is a sudden and significant loss of generation or addition of load. Under frequency load shedding is usually expected to operate when there is such a large mismatch between load and generation that normal governor action cannot be expected to restore nominal frequency to prevent equipment damage from sustained lowfrequency operation. Under frequency load shedding is usually applied to shed increasing blocks of load at discrete frequency levels. It is important that the frequency levels and time delays (if any) be coordinated with any turbine/generator under frequency protection that is applied on the system so that all the load that is available to be shed, is shed before any generator is tripped to protect it from damage. Voltage stability load shedding may be applied to prevent extended system operation at low voltages. The possibility of such operation arises when there is a lack of reactive power required to maintain system、 voltage levels within acceptable limits. This voltage stability load shedding is often initiated by sustained low voltages with or without the presence of other indicators of insufficient reactive power availability. It is important that the voltage stability load shedding be coordinated with any generator protection that may operate during low voltages or high reactive power output levels. Some types of generator protection that could operate during high reactive power output are field overload protection, exciter protection, exciter transformer protection, and field ground fault protection. Some types of generator protection that could operate during low voltages (and associated high currents) are voltage restrained or controlled overcurrent protection, under impedance protection, and stator overload protection. Other system control actions, which respond to low voltages, include the following: Reactor and capacitor switching to increase the amount of reactive power supplied to the system, HVDC fast ramping, tie line switching, and generator governor action to reduce the real power flow in the transmission system and, thereby, reduce reactive power demand. Again, generator protection, which responds to low voltages. and high currents, should coordinate with such control actions. Some special protection schemes separate out of step systems at suitable tie points. Generator protection, which responds to outofstep conditions, should also coordinate with such schemes. Generator outofstep protection, under impedance protection and voltage controlled or restrained overcurrent protection may undesirably respond to outofstep conditions before system special protection schemes can act to remove the outofstep condition. Some other special protection schemes operate to prevent thermal overload from damaging equipment. Such schemes usually shed load, separate system tie lines, or start local generation or take emergency control of HVDC. It is important that generator protection, which might respond to unusually heavy load, should coordinate with any thermal overload system special protection schemes. Some generator protection that may respond to heavy load includes stator overcurrent protection, stator overload protection, and field overload protection. 中文翻譯： 大型發(fā) 電機(jī)干擾下發(fā)電機(jī)保護(hù)的性能 內(nèi)容摘要 : 干擾是任何一個(gè)電力系統(tǒng)從一個(gè)穩(wěn)定運(yùn)行狀態(tài)過渡到另一個(gè)穩(wěn)定狀態(tài)都存在的，保護(hù)用的繼電器在這個(gè)過渡時(shí)期會(huì)測(cè)量到不正常運(yùn)行狀態(tài)。s turbine governor control, system frequency, and interchange schedules and dispatches corrections to the unit39。 aP accelerating power. The mechanical power mP is provided by the turbine and the average mechanical power must be equal to the average electrical power. When a system disturbance occurs, there is a change in one of the parameters of the electrical power equation. For faults, typically, the reactance between the generator and the load( tX )， the load voltage( tE )， or some bination of these two parameters causes the electrical power to change. For example, for a short circuit, the load voltage