第一章1-2-1对例1-2,取kV1102BU,MVASB30,用准确和近似计算法计算参数标幺值。解:①准确计算法:选取第二段为基本段,取kV1102BU,MVASB30,则其余两段的电压基准值分别为:9.5kVkV1101215.10211BBUkUkV6.66.6110110223kUUBB电流基准值:kAUSIBBB8.15.9330311kAUSIBBB16.011033032233302.62336.6BBBSIkAU各元件的电抗标幺值分别为:发电机:32.05.930305.1026.0221x变压器1T:121.05.3130110121105.02222x输电线路:079.011030804.023x变压器2T:21.01103015110105.02224x电抗器:4.03.062.26.6605.05x电缆线路:14.06.6305.208.026x电源电动势标幺值:16.15.911E②近似算法:取MVASB30,各段电压电流基准值分别为:kVUB5.101,kAIB65.15.103301kVUB1152,2300.153115BIkAkVUB3.63,3302.7536.3BIkA各元件电抗标幺值:发电机:26.05.1030305.1026.0221x变压器1T:2300.1050.131.5x输电线路:073.011530804.023x变压器2T:4300.1050.2115x电抗器:44.03.075.23.6605.05x电缆线路:151.03.6305.208.026x电源电动势标幺值:05.15.1011E习题2解:(1)准确计算:3(110)115BBUUkV322220115209.1121BBUUkVk312122010.51159.1121242BBUUkVkk各段的电流基准值为:1122014.0339.1BBBSIkAU222200.633209.1BBBSIkAU332201.133115BBBSIkAU各元件的电抗标幺值分别为:发电机:21210.52200.300.292400.89.1x变压器1T:222210.52200.140.143009.1x输电线路:322200.422300.49209.1x变压器2T:24222202200.140.12280209.1x(2)近似算法:kVUB5.101,122012.10310.5BIkA2231BUkV,22200.553231BIkA3121BUkV,32201.053121BIkA各元件电抗标幺值:发电机:12200.300.22240/0.8x变压器1T:22200.140.10300x输电线路:322200.422300.40231x变压器2T:42200.140.11280x习题3要点:以下摘自《国家电网公司电力系统安全稳定计算规定》:2.4.1暂态稳定是指电力系统受到大扰动后,各同步电机保持同步运行并过渡到新的或恢复到原来稳态运行方式的能力,通常指保持第一、第二摇摆不失步的功角稳定,是电力系统功角稳定的一种形式。2.5.1动态稳定是指电力系统受到小的或大的扰动后,在自动调节和控制装置的作用下,保持较长过程的运行稳定性的能力,通常指电力系统受到扰动后不发生发散振荡或持续的振荡,是电力系统功角稳定的另一种形式。两者均是系统受扰动后恢复的能力,均属于功角的稳定,暂态是偏移正常运行状态很小的暂时的状态,能很快达到正常状态,而动态稳定更多依靠于自动调节和控制装置的作用,时间较长,波动较大。1.3.1(1)KAzUImm45.9943.03.6*2(2)o64.57505.0797.0arctanarctanrx005.0505.0*314797.0RLTa0|0|mItaeti20064.27cos45.9)64.27cos(45.9oo或taeti20037.8)64.27cos(45.9otbeti20064.147cos45.9)64.147cos(45.9ootceti20036.92cos45.9)36.92cos(45.9oo或:将au改写成)90sin(3.6*2otua,带入公式得taeti20036.62sin45.9)36.62sin(45.9ootbeti20064.57sin45.9)64.57sin(45.9ootceti20036.182sin45.9)36.182sin(45.9oo(3)a,b,c相初始相角分别||为62.36o,57.64o,177.64o,故a相瞬时电流最大KAeIIimmM73.10*005.001.0(4)由90|90|得=57.64或-122.361.3.2a相KAIICmm12.8)64.579030sin(45.9)309030sin(18.0*2)sin()sin(|0||0|B相7.86KAc相0.26KA2.2.1取基准值MVASkVUBB240,8.13,则kAUSIBBB04.108.13*3240*3发电机次暂态电抗标幺值216.0*cos/22''''*BBNNddUSSUxx变压器的电抗标幺值13.0**100(%)22*BBNTNSTUSSUUx电流标幺值89.2216.013.01''*mI第二章2-2-1一发电机、变压器组的高压侧断路器处于断开状态,发电机空载运行,其端电压为额定电压。试计算变压器高压侧突然三相短路后短路电流交流分量初始值mI。发电机:MWSN200,kVUN8.13,9.0cosN,92.0dx,32.0dx,2.0dx变压器:MVASN240,kVkV8.13/220,13(%)SU解:取基准值kVUB8.13,MVASB240电流基准值kAUSIBBB04.108.1332403则变压器电抗标幺值13.0.813240240.81310013100%2222BBNTNSTUSSUUx发电机次暂态电抗标幺值216.08.132409.02008.132.0cos22222BBNNNddUSSUxx次暂态电流标幺值86.222.013.011dTxxI有名值kAIm05.3804.1086.222-3-1例2-1的发电机在短路前处于额定运行状态。(1)分别用E,E和qE计算短路电流交流分量I,I和dI;(2)计算稳态短路电流I。解:(1)010U,32185.0cos110I短路前的电动势:4.7097.132167.01000jIxjUEd3.11166.132269.01000jIxjUEd957.0)321.41sin(10dI754.01.41cos10qU01.1957.0269.0754.0000ddqqIxUE92.2957.026.2754.0000ddqqIxUE所以有:57.6167.0/097.10dxEI33.4269.0/166.10dxEI75.3269.0/01.10dqdxEI(2)29.126.2/92.2/0dqxEI2-4-1解:对不计阻尼绕组的情形dddqqqqdffffdddadfqqqfaddffUriUriUrixixixixixi由定子三相开路:di=qi=0得:fddqaddiUxdtqqdadfUxi0ffffffffdiUririxdt可以解得:00ffrtxfffffUUierr带入得:0ffrtxfdadfUUxer000()(1)ffffrrttxxfffqadadfffUUUUxexerrr可得:0cossin1cos(120)sin(120)1cos(120)sin(120)1adbqcUUUUUUcossincos(120)sin(120)cos(120)sin(120)dqdqdqUtUtUtUtUtUt00cossin(1)ffffrrttxxffaadadffUUUxetxtexr00cos(120)sin(120)(1)ffffrrttxxffbadadffUUUxetxtexr00cos(120)sin(120)(1)ffffrrttxxffcadadffUUUxetxtexr2-5,6-1i(1e)i0*i0**i(1e)ddtqmTddLqGdLqtqmLTGqLddLExxuxExuxxx2-5,6-2励磁突增前:|0||0||0||0|I=1.317.5x1.3550.31.31cos(50.37.5)50.30.9650.31.31sin(50.37.5)(50.390)0.8939.3GLQGqqqUjxEUJIII而q|0|GE=U+j1.8450.3ddqqxIjxI由|0||0|U0.1ffU得:0.184qmE0.260.260.260.26i(1e)0.136(1e)i00.136(1e)cos*u(1e)0.027(1e)u0u0.027(1e)sinddttqmTddqqtattqmLTGqdLGdtGaExxitExxxt设励磁突增前:|0||0|2cos(t15)2*1.31cos(t7.5)GaaUi则有:0.26|0|0.262*1.31cos(t7.5)0.136(1e)cos2cos(t15)0.027(1e)sintaaatGaiiitUt第三章3-1-1j0.15j0.075j0.1j0.1j0.1-1-1x1j0.075x2-1;601315.01.012.0j111jjjX;7003915.0075.016013j112jjjX9487.17j700391jI;6154.4075.06013075.0f1jjjjIIG;6667.6075.0601360135.0f32jjjjIIIGG2268.155.10*3606154.4''1GI9944.215.10*3606667.6''2GI3-1-2-1x7X3+x4+x689856.31;2565.0111;17826.0)(5.01)(5.011982196437218XIXXXXXXXXXXXf758.57213100022128f1XXXXXIIG34.102131000)(5.0)(5.0)(5.05.02211643216437f32X