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Điều chỉnh công suất tác dụng và công suất phản kháng của máy phát đồng bộ ' "L*'4\R'+<'NZ%&'/*0%'1#$%&'>2M*'/*0%'1+23%&'>8Y%'1+R.'/ổ*'1+h$'/*78']*0%'4\R'EL%' g8D1'+$64'4[%&'45'1+K'45'1#23%&'+T9'18.'1L*']+Y%&'1+R.'/ổ*'%+2%&'N$'/*78']*0%'=C%' +,%+'4\R'>2M*'/*0%'(,'4G%'1+*H1'9+L*'1+R.'/ổ*'4+H'/<'>,('=*04'4\R'4-4'( '9+-1'/*0%I' N$'/5'1#`%'1+@4'1H'9+L*'/*78'4+_%+'4Y%&'E8D1'1-4'NS%&'P'=,'4Y%&'E8D1'9+L%']+-%&'Q'4\R' ( '9+-1'/*0%'/:%&';<A' Nguyn Vn ụ - HL !! Hình 25-4. Công suất tác dụng và công suất chỉnh bộ của máy phát điện đồng bộ cực ẩn ' ' P (' B ' A ' P' ' ( ' t ' ' | ' P 4;' P ' "R'+ã.'ge1'=D%'/7'ở'+R*'1#23%&'+T9'/*K%'+J%+A'"#23%&'+T9'1+d'%+D1'>,'1#23%&'+T9' ( '9+-1'/*0%'>,('=*04'1#$%&'+0'1+?%&'/*0%'>@4'45'4Y%&'E8D1'=Y'4Z%&'>M%'=M*'qI'u'' 4$%E1I'+R.'%5*']+-4'/*'1ổ%&'4Y%&'E8D1'4\R'4-4'( '9+-1'/*0%'/R%&'>,('=*04'E$%&'E$%&' 1#$%&'+0'1+?%&'#D1'>M%'E$'=M*'4Y%&'E8D1'4\R'( '9+-1'/*0%'/R%&'/2T4'ge1I'N$'/5'=*04' /*78'4+_%+'P'=,'Q'4\R'( '9+-1'/*0%'/5']+Y%&'>,('1+R.'/ổ*'q'=,'u'4\R'+0'1+?%&'/*0%A' "#23%&'+T9'1+d'+R*'>,'1#23%&'+T9'4+_'45'+R*'+$64'=,*'( '9+-1'/*0%'45'4Y%&'E8D1'12b%&' /2b%&'>,('=*04'E$%&'E$%&'=,'E@'1+R.'/ổ*'4+H'/<'>,('=*04'4\R'(<1'( 'Ec'>,('1+R.'/ổ*' qI'u'4+8%&'4\R'4L'4-4'( '9+-1'/*0%'/5A' 25.3.1. Điều chỉnh công suất tác dụng P của máy phát điện đồng bộ 1. Tr*ờng hợp máy phát điện làm việc trong hệ thống điện công suất vô cùng lớn ở'1#23%&'+T9'%,.'q'=,'u'>,']+Y%&'/ổ*'%`%' %H8'&*O'NP%&'/*0%']z4+'1+z4+'* 1 ']+Y%&'/ổ*'1+J'E' >,'+l%&'E?'=,'1+h$';*K8'1+d4'tt~ v'1+J' P'>,' +,('E?'4\R'&54''=,'/23%&';*K8'N*ễ%'4\R'%5' 45'NW%&'%+2'/ã';*H1'1#`%'+J%+'tt~9A'ở'4+H'/<' >,('=*04'g-4'>C9'4Y%&'E8D1'1-4'NS%&'P'4\R'( ' d%&'=M*'&54' '%+D1'/j%+'9+L*'4^%';l%&'=M*' 4Y%&'E8D1'4b'1#`%'1#S4'>,(' q8R.'( '9+-1' /*0%A'p23%&';*K8'N*ễ%'4Y%&'E8D1'4b'4\R'/<%&' 4b'Eb'4D9'/2T4';*K8'1+j';l%&'/23%&'1+ẳ%&' E$%&'E$%&'=M*'1#S4'%&R%&'=,'4}1'/64'1z%+'&54'ở' /*K(' A'1#`%'+J%+' t!~wA'B+2'=C.'(8?%'/*78' 4+_%+'4Y%&'E8D1'1-4'NS%&'P'4\R'( '9+-1'1+J' 9+L*'1+R.'/ổ*'&54'I'%&+ĩR'>,'&*R$'/*K('A';l%&'4-4+'1+R.'/ổ*'4Y%&'E8D1'4b'1#`%'1#S4' ( A' CY%&'E8D1'1-4'NS%&'4@4'/W*'P ( '(,'( '9+-1'/*0%'45'1+K'48%&'4D9'4+$'+0'1+?%&'/*0%' d%&'=M*']+*' 0= d dP A'á9'NS%&'/*78']*0%'/5'/?*'=M*';*K8'1+d4'(tt~ vo'4\R'( '9+-1'/:%&' ;<'4@4'ẩ%'E8.'#R'/2T4' ( ''9| | '=,' ''''''''''''''''''''''''''''''''''''''''''''' d m x mUE P = ''''''''''''''''(t!~ o'' C[%&'%+2'=C.'/?*'=M*'( '4@4'>:*I'1i'(tt~ vo'45'1+K'E8.'#R'/2T4'&54' ( 'g-4'/j%+' ;ở*n' B ABA m 4 8 cos 22 + = ' 1#$%&'/5n'''' d x mUE A = I''''' = dq xx mUB 11 2 ' =,'''''''' m dq m d m xx mU x mUE P 2sin 11 2 sin 2 += ''''''(t!~to' Nguyễn Văn Đô - ĐHĐL !6 ' f+*'/*78'4+_%+'4Y%&'E8D1'1-4'NS%&'4G%'4+x'U'#l%&'( '9+-1'/*0%'/:%&';<'4+_'>,(' =*04'æ%'/j%+'1Ü%+']+*'|'<'θ''<'θ ( A'pK'1+D.'#â'/*78'/5I'&*L'1+Q'#l%&'( '/R%&'>,('=*04'ë' &*R$'/*K('A'd%&'=M*'θ '<'θ ( A'BH8'N$'(<1'%&8.`%'%+^%'%,$'/5'4Y%&'E8D1'4b'P 4b '4\R' /<%&'4b'Eb'4D9'1V%&'>`%'1#$%&'(<1'1+3*'&*R%'%&}%I'ER8'/5'>W*'1#ë'=7'1#j'E?';R%'/G8'1+J' #Y1$'4\R'4-4'( '9+-1'/*0%'Ec'q8R.'%+R%+'>`%A'B+2'=C.'&54'θ'Ec'1V%&'1+`('+∆θ'=,' 12b%&'d%&'4Y%&'E8D1'P'Ec'1V%&'1+`('∆PA'FJ'>x4'/5'4Y%&'E8D1'4b'P 4b '/·'1#ë'=7'1#j'E?';R%' /G8'%`%'P'+'∆P'>'P 4b I']H1'q8L'>,'#Y1$'Ec';j'&+J('=,'( '9+-1'/*0%'1#ë'>W*'>,('=*04'ë'&54' θ';R%'/G8'ER8'=,*'4+8']ú'NR$'/<%&A'"#-*'>W*'%H8'( '9+-1'/*0%'>,('=*04'g-4'>C9'ë'θ t '>' θ ( I'=z'NS'ë'/*K('B'1#`%'+J%+'t!~w'1+J']+*'4Y%&'E8D1'4b'1+R.'/æ*'%+2'1#`%I'&54'θ'1V%&' 1+`(''∆θ'Ec'>,('4+$'P'4\R'( '9+-1'/*0%'&*L(I'%+2'=C.'P'<'P 4b I']H1'q8L'>,'#Y1$'q8R.' %+R%+'1+`(I'&54'θ'4,%&'1V%&'=,'( '9+-1'/*0%'Ec'(D1'/:%&';<'=M*'>2M*'/*0%A' "i'%+O%&'/*78'%5*'1#`%'1R'1+D.'#l%&I']+*'/*78'4+_%+'4Y%&'E8D1'1-4'NS%&'(,'(8?%' &*O'4+$'( '9+-1'/*0%'>,('=*04'æ%'/j%+'1+J'9+L*'45'/*78']*0%'ER8n' ''''''''''''''''''''''''''''''''''''''''''''' 0> θ d dP '''''''''''''''''''''''''''''(t!~vo' 1#$%&'/5' θ d dP /2T4'&y*'>,'4Y%&'E8D1'4+_%+';<'/64'1#2%&'4+$']+L'%V%&'&*O'4+$'( '>,(' =*04'/:%&';<'1#$%&'>2M*'/*0%'=,'/2T4']z'+*08';l%&'P 4; A' "i'4-4';*K8'1+d4'(tt~ vo'=,'(tt~ wo'E8.'#R'/2T4'4Y%&'E8D1'4+_%+';<'/?*'=M*'( ' 4@4'>:*n' ''''''''''''''''''''''''''''' θθ 2cos 11 cos 2 −+= dqd cb xx mU x mUE P '''''''''''''(t!~wo' =,'/?*'=M*'( '4@4'È%n' '''''''''''''''''''''''''''''''''''''''''''''' θcos d cb x mUE P = '''''''''''''''''''''''''''''''''''(t!~!o'''' p23%&';*K8'N*Ô%'4\R'4Y%&'E8D1'4+_%+';<'%+2'1#`%'+J%+'t!~wA'"R'1+D.']+*']+Y%&'1L*' (θ'•'|oI']+L'%V%&'4+_%+';<'1d4']+L'%V%&'4\R' ∆P'&*OR'4Y%&'E8D1'4b'/2R'=,$'( '=,' 4Y%&'E8D1'1-4'NS%&'/2R'#R'>2M*'/*0%'d%&'=M*'E@'1+R.'/æ*'∆θ'>,('4+$'( '9+-1'=É%'N8.' 1#J'>,('=*04'/:%&';<'=M*'>2M*'/*0%'>,'>M%'%+D1I'4P%']+*'θ'•'θ ( '1+J']+L'%V%&'4+_%+';<' ;l%&']+Y%&A' "#`%'1+@4'1H'=C%'+,%+'/K'/7'9+P%&'1#23%&'+T9'q'+$64'E'&*L('+$64'%+O%&'%&8.`%' %+^%']+-4'>,('4+$'4Y%&'E8D1'P'/2R'#R'>2M*'/*0%'&*L('1+h$'%+2%&'=É%'N8.'1#J'/2T4'/:%&' ;<I'( '9+-1'/*0%'1+23%&'>,('=*04'=M*'4Y%&'E8D1'/j%+'(d4'P /( 'd%&'=M*'θ'<'v| | A' B+2'=C.']+L'%V%&'q8-'1L*'4\R'( '9+-1'/*0%'/:%&';<'/2T4'g-4'/j%+'1X'E?n' (d m m P P k = ' &y*'>,'+0'E?'%V%&'>@4'q8-'1L*A' p?*'=M*'( '4@4'È%' (d m k θsin 1 = ' Nguyn Vn ụ - HL !7 Hình 25-5. Điều chỉnh công suất phản kháng của máy phát điện đồng bộ 0 E & ' 0 E & ' db xIj & db xIj & & U ' B ' '' ' ' ' ' ' t ' ' A ' | ' , I & ' I & ' Hình 25 - 6. Đặc tính hình V của máy phát điện đồng bộ' "+*H8'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' ]z4+'1+z4+' P ' ' I|P /(' cos =1' i t0 ' n ' Q8-'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' ]z4+'1+z4+' i t ' P ' ' |I!P /(' A ' 0 ' '>'|' '<'|' m ' I ' B ' P ' '|I t !P /(' "+h$'q8.'/j%+'1+J'4G%'/L(';L$'] ( '>' I7'=,'(8?%'%+2'=C.'1+J'( '9+L*'45'1X'E?' %&}%'(W4+'f'>M%I'%&+ĩR'>,'g N '9+L*'%+k'(+$64']+h'+ở'>M%oA' CG%'4+x'U'#l%&']+*'/*78'4+_%+'4Y%&'E8D1'1-4'NS%&'PI'N$''1+R.'/ổ*'%`%'4Y%&'E8D1' 9+L%']+-%&'4[%&'1+R.'/ổ*'1+h$A' 2. Tr*ờng hợp máy phát điện công suất t*ơng tự làm việc song song G*L'1+Q'45'+R*'( '9+-1'/*0%'4Y%&'E8D1';l%&'%+R8'>,('=*04'E$%&'E$%&A'ở'1#23%&' +T9'%,.I'1#$%&'/*78']*0%'1L*'4\R'>2M*'/*0%']+Y%&'/ổ*I']+*'1V%&'4Y%&'E8D1'1-4'NS%&'4\R' (<1'( '(,']+Y%&'&*L('12b%&'d%&'4Y%&'E8D1'1-4'NS%&'4\R'( ']*R'1+J'1G%'E?'4\R'>2M*' /*0%'Ec'1+R.'/ổ*'4+$'/H%']+*'45'E@'4^%';l%&'(M*'=,']+*H%'4+$'+<'NZ%&'/*0%'9+L*'>,(' =*04'1#$%&'/*78']*0%'1G%'E?']+-4'/j%+'(d4A'FJ'=C.I'/K'&*O'4+$'u''4$%E1']+*'1V%&'4Y%&' E8^1'1-4'NS%&'4\R'(<1'( '1+J'9+L*'&*L('4Y%&'E8D1'1-4'NS%&'4\R'( ']*RA'C+z%+'4[%&' ;l%&'4-4+'/5'(,'45'1+K'1+R.'/ổ*'E@'9+^%'9+?*'4Y%&'E8D1'1-4'NS%&'&*OR'+R*'( A' 25.3.2. 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