【文章內(nèi)容簡介】 的級數(shù)決定的。3)The testing of a crossfield generator will be described in this section with chief reference to the tests that are normally taken on every machine before it leaves the makers ，它主要涉及每臺電機在離開制造廠前應進行的試驗。1)All radiant energies have wavelike characteristics, which are analogous to those of waves moving through radiant energies have wavelike characteristics analogous to those of waves moving through ，與水中移動的波的特征相似。2)The instruments present include some digital ones which are relative to instruments present include some digital ones relative to 。 the system expands and higher voltage levels bee necessary for transmission, the older transmission lines are often relegated to subtransmission ，舊的輸電線路往往被移交給中壓輸電功能。, the capability of lines of the same length varies at a rate somewhat greater than the square of the ，長度相同的線路的容量，以比電壓的平方略大的比率變化。 definite capability can be specified for a line of a given voltage, however, because capability is dependent on the thermal limits of the conductor, allowable voltage drop, reliability, and requirements for maintaining synchronism between the machines of the system, which is known as ，無法為給定電壓等級的線路指定確切的容量，這是因為容量取決于導線的發(fā)熱極限、允許的電壓降落、可靠性和維持系統(tǒng)中的發(fā)電機同步的要求（這被認為是穩(wěn)定性）。 exists between the conductors and is the charge on the conductors per unit of potential difference between ，等于導體上的電荷（電量）與導體間的電勢差之比?；颍弘娙荽嬖谟趯w之間，等于導體之間單位電壓對應的電量?！癆 per unit of B” 表示 “單位B上的A” 或者“A/B”。 of the three phases can be restored by exchanging the positions of the conductors at regular intervals along the line so that each conductor occupies the original position of every other conductor over an equal distance, as shown in ，沿線路方向每隔一定間隔就交換導線位置，使每根導線都能占據(jù)具有相同輸電距離的其他各導線的初始位置，以重建三相平衡。Electrical energy can be stored in two metal plates separated by an insulating a device is called capacitor or ability to store electrical energy is is measured in farads 電能可儲存在由一絕緣介質(zhì)隔開的兩塊金屬極板內(nèi)。這樣的裝置稱之為電容器，其儲存電能的能力稱為電容。電容的測量單位是法拉。 industrial customers are supplied by primary feeders at this voltage level from the primary system, which also supplies the distribution transformers providing secondary voltages over singlephase threewire circuits for residential and mercial customers at 120 V/240 。一次系統(tǒng)也給經(jīng)過單相三線電路為居民用電和商業(yè)用戶提供120V/240V二次電壓的配電變壓器供電。 illustrated in , the aggregated load represented at a transmission substation(bus A)usually includes, in addition to the connected load devices, the effects of substation stepdown transformers…，在輸電變電站（母線A）所給出的集合負荷，除了所連接的負荷設備以外，通常還包括變電站降壓變壓器的影響……。, loads are devices those consume electric energy or electric power consumed by customers mainly in distribution ，負荷是主要在配電網(wǎng)中消耗電能的設備或者由用戶消耗的功率。 loads absorb electric energy from the power system and converts it into energy of other forms, which may be heat energy to heat water or to melt irons, or mechanical energy to drive a machine, ，并將其轉(zhuǎn)換為其他形式的能量，可能是燒水或溶化鋼鐵的熱能，或者是驅(qū)動機器的機械能等。 kind of loads, especially those consume energy calculated by standard coals more over 10 thousands of tons per year, has a name of high energy consuming ，尤其是那些年耗能萬噸標準煤以上的負荷，被稱為高耗能負荷。 synchronous machine as an AC generator driven by aturbine is the device which converts mechanical energy to electrical energy, in powers ranging up to ，同步電機是將機械能轉(zhuǎn)化為電能的設備，其功率范圍高達1500MW。