Check the following components are in proper place:
AC breaker 1QF is in open position,field-current breaker MK is in open position and green lamp H2 is light;
AC and DC working power switch 1QS and 2QS of regulator are closed, AC and DC voltage is normal;
All F usesa i c re p n losedm DC220V v oltageoosition, f easuref f ieldp FlashingF ower uses U1,FU2 and make sure the amplitude and direction of voltage are correct;
Switch 3QK“Auto/Man”is in auto position;
Select “local” of “local/master” switch 5QK;
The generator reaches rated speed 3000 r/min; having raising voltage condition, start to raise voltage:
1) Close AC breaker 1QF;
2) Press button HA, the red indicator light is on at the same time;
3) Press button SB1,regulator is running and generator terminal voltage rise up.
4) When the terminal voltage is stabilized in setting voltage by soft start, increase voltage to rated terminal voltage nearby through “increase/decrease” switch 2QK;
5) A f t e r s u c c e s s f u l s y n c h r o n i z a t i o n , s e l e c t “c o n s t a n t p o w e r f a c t o r” o r “c o n s t a n t r e a c t i v e” operation through “operation methods” switch 4QK.
Note:
If s elect“constant c ” o f“operation murrent ” s witch3ethods t QK,p “field fhen lashingress” b utton
S B 3 , t h e g e n e r a t o r t e r m i n a l v o l t a g e c a n o n l y r i s e t o 5 % o f v o l t a g e o f r a t e d u n l o a d e d r o t o r c u r r e n t , t h e n c o n t i n u e t o i n c r e a s e e x c i t a t i o n t o r a t e d t e r m i n a l v o l t a g e v a l u e n e a r b y t h r o u g h
“inc reas e/decr ease” butt on 2QK. if the vol t age c an not mai ntai n, incr ease manua l set val ue by increase button 2QK then press “field flashing” button SB3;
on;
3.9 Fault warning and processing
Phenomenon Processing
P T b r e a k line
If P T b r e a k l i n e , t h e e x c i t a t i o n r e g u l a t o r s e n d
“PT break line” signal, “channel fault” indicator light is on, if excitation private PT break line, switch the operation method to manual operation automatically.
Contact f o or verhauling,c heck
e x c i t a t i o n P T a n d r e l a t e d c i r c u i t . Ch e c k P T i n s u r a n c e ,
recover i nstrumentP v T oltage,
and return in accordance with the signal.
V/Hz limit
When t he generat or t er minal vol tage r is e t o a cert ai n degree over rated value, the regulator send “V/Hz limit” signal, if the
voltage continue to rise, excitation unit is switched to manual operation, the regulator is out of service soon.
Decrease excitation before the
r e g u l a t o r i s o u t o f s e r v i c e , d e c r e a s e t h e t e r m i n a l v o l t a g e
t o r a t e d v a l u e n e a r b y , p r e s s
“r e t u r n” b u t t o n t o e r a s u r e warning signal.
When t ghe eneratorr s l evolutiont a c v peed owers o ertain alue,
the terminal voltage lowers automatically;
When the generator revolution speed is below 2700 rev/min, the regulator is out of service automatically.
Press “return” button to return.
Over excitation limit
Wh e n t h e e x c i t a t i o n c u r r e n t i s 1 . 1 t i m e s g r e a t e r t h a n r a t e d
e x c i t a t i o n c u r r e n t f o r a l o n g t i m e , t h e r e g u l a t o r s e n d
“o v e r e x c i t a t i o n l i m i t” s i g n a l , “c h a n n e l w a r n i n g” i n d i c a t o r l i g h t i s o n , i f o v e r e x c i t a t i o n s t a t u s c o n t i n u e s f o r a c e r t a i n time, the regulator will switch to manual operation;
If t h e e x c i t a t i o n c u r r e n t i s g r e a t e r t h a n o v e r e x c i t a t i o n p r o t e c t i o n s e t v a l u e , d e l a y f o r 1 . 5 s e c o n d s , t h e
regulator latches pulse and quit operation.
Decrease excitation, lower the excitation current to normal.
Under excitation limit
When the generator is in under excitation operation, reactive
a n d n e g a t i v e , e n t e r i n t o t h e s e t l i m i t l i n e , t h e r e g u l a t o r s e n d
“u n d e r e x c i t a t i o n l i m i t” s i g n a l , “c h a n n e l w a r n i n g” i n d i c a t o r l i g h t i s o n , i f u n d e r e x c i t a t i o n s t a t u s c o n t i n u e s f o r a c e r t a i n extent, the regulator will switch to manual operation;
Op e r a t e “i n c r e a s e” b u t t o n ,
increase g eneratorr t eactive, he
p o w e r f a c t o r k e e p s n e a r t h e rated value.
Lo s s o f
pulse
If t h e t r i g g e r p u l s e i s l o s t i n o p e r a t i o n , t h e r e g u l a t o r s e n d
“loss of pulse” signal, “channel warning” indicator light is on.
Co n t a c t f o r o v e r h a u l i n g ,
identify causes.
A/D fault If t h e r e i s f a u l t i n e x c i t a t i o n r e g u l a t o r m e a s u r e m e n t , t h e channel regulator is out of service automatically.
If t h e w a r n i n g s i g n a l c a n n o t
r e t u r n , c o n t a c t f o r
overhauling.
Wh e Gn E X e - x2 c 0 i 0 t 0 a t i o n r e g u l a t o r s e n d w a r n i n g s i g n a l , p r o v i d e d t h e
generator’s a ctivea r nd o eactivei n nperationn o a s s ormal,t p a o eedt t f ny witching, hen rocess ccording o he
a b o v e t a b l e . If t h e g e n e r a t o r’s a c t i v e a n d r e a c t i v e o p e r a t i o n s w i n g s s h a r p l y ( o v e r e x c i t a t i o n a n d u n d e r excitation) and can not return to stable status when GEX-2000 gives warning, the operator should decide
whether to stop the machine for processing in accordance with specific conditions.
4 Maintenance of equipment
4.1 Daily inspection
The operator should check the following content in inspection:
1) If there is warning signal of regulator and indicator light;
2) Whether the instrument works stably, indicates normally;
3) Whether the regulator operation method fits actual situation;
4) Whether there is overheating components, peculiar smell and abnormal sound, whether silicon controlled temperature rise is within the normal range.
4.2 Maintenance 1) Cabinet cleaning;
2) Check power supply unit, measure every voltage value with voltmeter;
3) imitate the checking of input channel, check input of PT, CT and excitation current, to see whether the deviation is within allowed range;
4) Check silicon controlled trigger pulse and rectified waveform;
5) Check and test operation and linkage circuit etc.
5 Upper computer monitoring
EXM-VER1.1 is the back-stage management software for GEX-2000C/D excitation system, the operating
d at a a nd p ar a m et e r o f ex c i t at i on u ni t ca n be t r a ns m i t t e d t o t he up pe r c om pu t e r t h r ou gh co m mu ni c a t i on ,
b a c k - s t a g e m a n a g e m e n t s o f t w a r e c a n r e a l i z e f u n c t i o n s o f o p e r a t i o n m o n i t o r i n g , p a r a m e t e r a d j u s t i n g , waveform analyzing and test guiding etc.
5.1 Installation and startup
Operating environment: Win9x/NT/2000/XP/2003
Hardware requirement: general desktop/industrial personal computer/laptop Software installation:
Do u b l e - c l i c k t o r u n i n s t a l l a t i o n d o c u m e n t s , c a r r y o u t s t e p b y s t e p a c c o r d i n g t o t i p s , a n d i n s t a l l t h e s o f t w a r e i n c o m p u t e r e a s i l y. Th e p r o c e d u r e c r e a t e s s h o r t c u t o n d e s k t o p , g e n e r a t e s f o u r
subfolders under installation directory, used for saving different files respectively.
5.2 Connection type 5.2.1 Single channel
If the upper computer is connected with excitation unit directly by panel connection, select single channel when startup software, as the graph below shows. Note that if select two-channel wrongly, it will result in slow communication speed.
5.2.2 Two-channel
Two excitation units must be connected through excitation unit RS485 interface. Connect 1 and 3 of 903 communication terminal to 485 interface of upper computer. If the upper computer has no 485 interface, users should provide USB→RS485 or 232→RS485 conversion interface for themselves.
5.3 System setting
After entering into interface, set in system options first. See the graph. Go from 5) first.
5) Rotor current range:
Brushless e xcitations s s ysteml t 2 houldstatic excitation s houldselect essg electhant o e5A,reater han r qual to 25A.
4) Serial port setting:
Set s erialp p ort o tarameterm i a f hisw s achinep p ns ccordanceo e u ith erial ort arameter ettings f xcitation nit.
Fo r c o n n e c t i o n t y p e u s i n g U S B → 4 8 5 c o m m u t a t o r , y o u c a n f i n d e n t r y p o i n t a d d r e s s a l l o c a t e d f o r t h e c o m m u t a t o r b y s y s t e m i n d e v i c e m a n a g e r o f t h i s m a c h i n e’s c o n t r o l p a n e l , i f t h e s y s t e m a l l o c a t e d e n t r y
point a ddressi g t sCOM4, c hangeireater t hana t bo ddressCOM4 ( included).After selow ettinge s very erial
p o r t p a r a m e t e r , c l i c k [ c h a n g e s e r i a l p o r t n a t u r e ] a n d t h e n [ a u t o c m d ] , t h e c o m m u n i c a t i o n w i l l s t a r t t o transmit data with correct setting.
3) Set operation channel
In t he condit i on of tw o-channel , data di spl ayed on hom e s cree n can be set here , ei the r CH 1 or CH2, or alternate displaying.
2) Set parameter password changing
Th e e q u i p m e n t o p e r a t i o n p a r a m e t e r w i l l i m p a c t t h e s a f e a n d s t a b l e o p e r a t i o n o f t h e w h o l e e x c i t a t i o n
e q u i p m e n t , t h e r e m u s t b e a c e r t a i n l i m i t s o f a u t h o r i t y f o r c h a n g i n g p a s s w o r d .
Here you can change password, the original of which is 9999.
1) Set clock
Press [system time setting], set the excitation clock time as the system time.
Graph: system options 5.4 Functions
5.4.1 Home screen
The graph below is the home screen content. Home screen is the main window in operation, its top half di spl ays exci t ati on syst em’s m ain gener ator volt age, rot or cur rent and react i ve pow er wi t h mim ic panel . The bottom half mainly displays some other important analog quantity, switching value status and current
o p e r a t i o n m e t h o d s . [ A c a b i n e t c u r r e n t ] a n d [ B c a b i n e t c u r r e n t ] o n l y a p p l y t o e x c i t a t i o n m o d e l o f t w o - cabinet current sharing, data displayed under other methods are invalid.
Graph: status display-switching value input
Graph: status display-analog quantity display
Graph: status display-internal mark 5.4.3 Fault record and SOE
When one channel of regulator break down, there will be a signal displaying in the home screen channel
status, y c oui dan nquiref i etailedi t s Put t heault m nformationoousea f r n inny hisault creen.ecord ncluding
f a u l t t y p e a n d t i m e , d o u b l e c l i c k a n d f a u l t b r i e f i n g i n f o r m a t i o n w i l l a p p e a r .
The faults can record 20 groups totally in accordance with the principle of first-in first out.
stored at the same time. Note that in setting parameter, LCD screen of excitation adjusting unit itself can not be below parameter setting interface, or there will be a conflict, the unit will report RAM fault at the same time.
[Note] In setting rated unit parameter, system option →5) rotor current range setting
Graph: parameter setting
Graph: parameter setting-PID setting 5.4.5 Waveform analysis
Carry out displaying, stretching, adjusting and printing for waveform of fault wave record and test wave
r e c o r d . Cl i c k [v a l u e ] o n t h e r i g h t h a l f a n d w i l l s h o w c u r s o r ( y e l l o w ) c o r r e s p o n d i n g d i s p l a y v a l u e . Click [attribute] and will show waveform attribute changing dialog box, you can change the name, unit,
sign, color, longitudinal proportion and longitudinal deviation of selected waveform in this dialog box.
Th e w a v e f o r m a n a l y s i s p r o v i d e s a b s o l u t e t i m e m a r k e r ( b l u e ) , r e l a t i v e t i m e m a r k e r ( r e d ) a n d c u r s o r
(yellow), the time below relative time marker is time difference between relative cursor (yellow); the time below yellow cursor is the time of cursor relative absolute time marker (blue).
5.4.6 Function of test
Th e s t r o n g t e s t g u i d i n g f u n c t i o n o f G E X - 2 0 0 0C / D r e g u l a t o r m a k e a l l e x c i t a t i o n r e g u l a t o r r e l a t e d t e s t a s template, in the process of test, complete the whole test in accordance with the template tips conveniently and fast, the software will record the test process automatically, generate test report automatically and print
test waveform.
6 Central control design guideline
Remote control needs operation buttons below:
1) Field suppression switch on corresponding DCS D/O send closing pulse pulse width is 500ms
2) Field suppression switch off corresponding DCS D/O s e n d o p e n i n g
pulse
pulse width is 500ms 3) Channel input order corresponding DCS D/O long pulse
4) Automatic/manual corresponding DCS D/O long pulse “1” i s a u t o m a t i c w h i l e
“0” is manual
5) Constant power factor corresponding DCS D/O long pulse “1” i s s e l e c t i n g t h e m e t h o d while “0” is exit
6) Constant reactive corresponding DCS D/O long pulse “1” i s s e l e c t i n g t h e m e t h o d while “0” is exit
7) Increase excitation corresponding DCS D/O increase
excitation, pulse
pulse width is 300ms 8) Decrease excitation corresponding DCS D/O decrease
excitation, pulse
pulse width is 300ms Remote operation indicates as follows:
1) Field suppression switch’s on/off indicates corresponding DCS D/I point field suppression switch;
2 ) C h a n n e l A a u t o m a t i c o p e r a t i o n i n d i c a t e s c o r r e s p o n d i n g D C S D / I p o i n t “C h a n n e l A a u t o m a t i c operation”;
3 ) C h a n n e l A m a n u a l o p e r a t i o n i n d i c a t e s c o r r e s p o n d i n g D C S D / I p o i n t “C h a n n e l A m a n u a l operation”;
4 ) C h a n n e l B a u t o m a t i c o p e r a t i o n i n d i c a t e s c o r r e s p o n d i n g D C S D / I p o i n t “C h a n n e l B a u t o m a t i c operation”;
5 ) C h a n n e l B m a n u a l o p e r a t i o n i n d i c a t e s c o r r e s p o n d i n g D C S D / I p o i n t “C h a n n e l B m a n u a l operation”.
Remote fault indicates as follows
1) Channel A fault corresponding DCS D/I point “channel A channel fault”;
2) Channel B fault corresponding DCS D/I point “channel B channel fault”;
7 Technical Description of GEX-2000C/D Microcomputer Excitation regulator
7.1 Unit features
As t h e n e w g e n e r a t i o n m i c r o c o m p u t e r e x c i t a t i o n p r o d u c t , G E X - 2 0 0 0C / D m i c r o c o m p u t e r e x c i t a t i o n regulator combines the latest research achievement of excitation system with the long experience of first g e n e r a t i o n e x c i t a t i o n r e g u l a t o r , a n d a p p l i e s f u l l y t h e l a t e s t c o m p u t e r c o n t r o l t e c h n o l o g y , d i g i t a l s i g n a l processor technology and advanced network and communication technology.
7.1.1 Main features
GEX-2000C/Dexcitation regulator has the following features:
1) The model is clear and accurate
G E X - 2 0 0 0C / D e x c i t a t i o n c o n t r o l s y s t e m u s e s s e r i e s c o n n e c t i o n t u n i n g p l u s r o t o r v o l t a g e n e g a t i v e
feedback, t a hec doptedm h omputationp t a m odels o c ave s asseda he ctual easurement f omputer imulation nd d y n a m i c s i g n a l a n a l y z e r , p r o v i n g t h a t t h e m o d e l h a s l i t t l e e r r o r a n d h i g h a c c u r a c y i n t h e p r o c e s s o f
discretization.
2) PSS-2A model is developed successfully first at home
Th e i m p r o v e d P S S - 2 A e l e c t r i c s y s t e m s t a b i l i z e r , w h i c h i s d e v e l o p e d s u c c e s s f u l l y f o r m a n y y e a r s , i s a p p l i e d i n G E X - 2 0 0 0C / D m i c r o c o m p u t e r e x c i t a t i o n r e g u l a t o r ; t h i s c a n b e t h e f i r s t r e g u l a t o r a t h o m e .
Di f f e r e n t w i t h P S S - 1 A w h i c h u s e s s i n g l e e l e c t r i c p o w e r s i g n a l a s i n p u t s i g n a l , P S S - 2 A e l e c t r i c s y s t e m
stabilizer a d doptsi s oublee s nputss oignala lectricp c ystemb r tabilizer f ccelerating ower ombined y evolving
s p e e d s i g n a l a n d e l e c t r i c p o w e r s i g n a l , s o l v e s t h e r e a c t i v e a n t i - r e g u l a t i o n p r o b l e m c a u s e d b y a c t i v e regulation.
3) High measurement accuracy
G E X - 2 0 0 0C / D g e n e r a t o r e x c i t a t i o n r e g u l a t o r u s e s w e e k l y w a v e 2 4 p o i n t A C s a m p l i n g a n d r a p i d
Fourier transform, e liminatesi o nmpactsd f m f ulla rifta aor h easurement1 b ccuracy, nd dopts igh-speed 2 its
A/D convertor ensuring accuracy and rapidity of measurement channel.
4) Strong network function
GEX-2000C/D generator excitation regulator has strong communication function; two-channel, regulator
a n d p o w e r c a b i n e t a r e c o n n e c t e d t h r o u g h r e l i a b l e f i e l d b u s C A N - B U S, r e a l i z i n g d a t a s h a r i n g a n d coordination control.
Every control channel provides USB and RS485 interface, realizing communication with upper computer and connection with power plant DCS system of regulator.
5) Convenient and friendly human-computer interface
G E X - 2 0 0 0C / D g e n e r a t o r e x c i t a t i o n r e g u l a t o r u s e s L C D w i t h l a r g e s c r e e n ( 2 4 0 * 1 2 8 ) a n d t r e e m e n u
s t r u c t u r e , i s c o n v e n i e n t a n d v i s u a l , c a n i n t e g r a t e k e y b o a r d f o r f u n c t i o n s o f p a r a m e t e r a d j u s t i n g , measurement display and test control etc, and display fault type and event SOE on this screen.
6) Convenient and practical upper computer software
E S M - V 1 . 1 i s t h e u p p e r c o m p u t e r m a n a g e m e n t s o f t w a r e s p e c i f i c f o r G E X - 2 0 0 0C / D m i c r o c o m p u t e r excitation regulator, realizes system functions including excitation system realtime data display, parameter
a d j u s t i n g , f a u l t r e c o r d , h i s t o r i c a l t r e n d c u r v e d i s p l a y , f a u l t w a v e f o r m d i s p l a y , d e f i n i t e v a l u e r e p o r t , automatic generation system and printout of test report etc.
7) Excitation regulator with top speed at home
G E X - 2 0 0 0C / D u s e s 3 2 b i t s D S P p r o d u c t o f U S T I C o m p a n y, t h e m a x i m u m s p e e d c a n b e 1 5 0 M H z, t h e
s t r o n g d a t a p r o c e s s i n g a b i l i t y a n d f a s t f l o a t i n g - p o i n t c a l c u l a t i o n o f D S P e n s u r e s a c c u r a t e d i g i t i z a t i o n o f excitation regulator model and other auxiliary functions of excitation regulator.
8) Highly integrated hardware design
G E X - 2 0 0 0C / D u s e s o v e r s i z e l o g i c d e v i c e C P L D , w h i c h c a n c o m p l e t e f u n c t i o n o f t r a d i t i o n a l d o z e n s o f
c h i p s c o m b i n a t i o n b y f l e x i b l e p r o g r a m m i n g , o n e c h i p c a n c o m p l e t e a l l p e r i p h e r a l c i r c u i t o f C P U . Simple hardware greatly reduces fault points of unit, and improves the overall reliability of system.
Wi t h w e l l d e s i g n a n d r e a s o n a b l e p r o c e s s i n g o f g r o u n d c o n n e c t i o n , f i l t e r i n g a n d s h i e l d e t c , t h e a n t i - interference capability of GEX-2000C/D unit reaches IEC level over strict three-level.
7.1.2 Operation environment
1) Altitude: not more than 3000m 2) Temperature: -10 ~40℃~40℃ ℃~40℃
3) Relative humidity: not more than 90%
4) Places without fire and explosion
5) Places without conductive dust and chemical etchant gas 6) Places without strong electromagnetic interference 7.2 Main functions and technical criteria
7.2.1 Main functions
Th e b a s i c t a s k o f G E X - 2 0 0 0C / D g e n e r a t o r e x c i t a t i o n r e g u l a t o r i s t o k e e p g e n e r a t o r t e r m i n a l v o l t a g e
c o n s t a n t , e n s u r e r e a s o n a b l e d i s t r i b u t i o n o f r e a c t i v e p o w e r b e t w e e n p a r a l l e l r u n n i n g u n i t s t h r o u g h a d j u s t m e n t s e t t i n g , a n d i m p r o v e t r a n s i e n t s t a b i l i t y a n d s t a t e s t a b i l i t y o f e l e c t r i c s y s t e m t h r o u g h r a p i d
excitation response. Except for the above basic control and adjustment function, GEX-2000C/D has other
a u x i l i a r y f u n c t i o n s i n c l u d i n g f a u l t w a v e r e c o r d , e v e n t r e c o r d , s y s t e m s e l f - c h e c k i n g a n d intelligent debugging etc.
7.2.1.1 Adjustment and control function
1) Automatic operation method is generator terminal voltage PID adjustment;
2) Manual operation method is generator constant excitation current PID adjustment;
3) Automatic/manual operation methods track mutually, interruptedly switch under various methods;
4) Generator constant power factor operation;
5) Generator constant reactive power operation;
6) Generator constant trigger angle operation;
7) Electric system stabilizer (PSS) auxiliary control
8) Channels tract mutually, interruptedly switch between channels;
9 ) R e ac t i v e p ow e r a dj u s t m en t , s e t p os i t i v e an d ne ga t i v e a d j us t m en t d i r e ct i on r an do m l y, ad j us t m e nt coefficient can be adjusted in range of 0-15%, differential is 0.1%;
1 0 ) T h e g e n e r a t o r u n i t’s s t a b l e o p e r a t i o n a n d r e a c t i v e s t e p l e s s r e g u l a t i o n i n t h e condition of unloaded and load;
11) Parameter online changing and recording, ensuring power down data not losing;
12) GEX-2000C/D generator excitation system can be connected to power plant DCS system through
serial port communication, transmit the data of regulation process to the upper computer in realtime, and receive the control order of upper computer;
13) Electric brake mode stop of hydroelectric generating set.
7.2.1.2 Limit and protection function 1) PT breaks line protection;
2) V/Hz protect ion (voltage/frequency protect ion), protect generator and transformer flux, carry out V/Hz limit and protection step by step;
3 )O v e r e x c i t a t i o n l i m i t a n d p r o t e c t i o n , p r o t e c t g e n e r a t o r r o t o r , c a r r y o u t
over excitation limit and protection step by step;
4) Underexcitation limit and protection;
5) Unloaded over voltage protection;
6) Trigger pulse lost detect;
7) Communication fault detect;
8) Silicon controlled fault detect;
9 ) P o w e r s u p p l y d e t e c t , m o n i t o r w h e t h e r C P U p o w e r s u p p l y a n d 2 4 V o p e r a t i n g p o w e r s u p p l y a r e normal;
All definite value of limit and protection and input/output of every protection can be adjusted on site.
7.2.1.3 Other auxiliary functions 1) Fault wave record
G E X - 2 0 0 0C / D g e n e r a t o r e x c i t a t i o n r e g u l a t o r r e c o r d m e a s u r e d d a t a o f 1 0 s e c o n d s b e f o r e a n d a f t e r f a u l t , including g veneratorU a oltages v UGREF, m anualsG1, utomaticv IFREF, t riggeraet alueet alueA ngle RF,
a c t i v e p o w e r P , r e a c t i v e p o w e r Q , r o t o r v o l t a g e R f d , r o t o r c u r r e n t I f d a n d g e n e r a t o r f r e q u e n c y F 0 . C o v e r a l l a n a l o g q u a n t i t i e s c o l l e c t e d , f a u l t w a v e f o r m c a n b e d i s p l a y e d o n L C D o f c o n t r o l l e r i t s e l f , a n d
transmitted to laptop through USB interface, displayed on EMS V1.1, processed and printed out.
2) Test wave record
G E X - 2 0 0 0C / D g e n e r a t o r e x c i t a t i o n r e g u l a t o r c a n r e c o r d t e s t w a v e f o r m t h r o u g h m a n u a l s t a r t m e t h o d , i f waveform of 10% step response, field suppression and load shedding etc, recording time is 1 second before
and 19 seconds after test start, record quantity is the same as fault wave record, while display method is the same as fault wave record.
3) Fault record
Record 20 fault values, fault time (correct to ms) and fault type in accordance with the principle of first-in first-out, all information can be shown on LCD or upper computer.
4) Event record
Record 20 event types and time (correct to ms) in accordance with the principle of first-in first-out, such as on/off of field suppression switch, input/output of channel and transition of operation methods etc.
5) Communication
G E X - 2 0 0 0C / D u s e s s t a n d a r d M O D B U S a g r e e m e n t , c a n c a r r y o u t c o m m u n i c a t i o n b e t w e e n c h a n n e l s a n d i n t e r f ac e be t w ee n ex ci t at i on r eg ul at o r a nd D C S s y s t em o r o t he r p ow er pl a nt m on i t or i ng s ys t e m t hr o ug h flexible communication methods, such as RS485 and CAN etc.
6) Software potentiometer
Pr o c e s s i n g c i r c u i t o f a l l a n a l o g q u a n t i t y c a n c e l s p o t e n t i o m e t e r , u s e s s o f t w a r e p o t e n t i o m e t e r that can be adjusted on menu, and debugging becomes more flexible and much easier.
7) Test
Wi t h k e y b o a r d o p e r a t i o n o f c o n t r o l l e r , c a r r y o u t v a r i o u s t e s t s o f r e g u l a t o r , s u c h a s t r a n s m i s s i o n t e s t o f
switching v over ealue, xcitationl imit,under e xcitationl imit,s r tep t esponseP c est,t P SS ompensation est, SS uncompensated test and AC exciter time constant test etc, can also record wave automatically.
7.2.2 Main technical criteria
7.2.2.1 Analog-digit converter input parameter
A/D sampling channel: 16
Analog quantity input overview:
Terminal voltage: Rated value 100V
System voltage: Rated value 100V
Stator current: Rated value 5A/1A
Rotor current: 75mv(from shunt)
Rotor voltage: Actual voltage
Exciting current of exciter: 75mv(from shunt)
Standby test signal: -2V~+2V(not isolated)
7.2.2.2 Volume of switching value input/output 1) Input of photoelectric isolating No. 16;
2) Output of switching value No.12, output of relay No. 12.
7.2.2.3 Output parameter
1 ) Tr i g g e r p u l s e : s i x - p h a s e d o u b l e p u l s e f o r t h r e e - p h a s e f u l l r e c t i f i e r b r i d g e , p u l s e w i d t h i s 400uS, can trigger under 4 groups three-phase full rectifier bride of parallel operation at the same time.
2) D/A output: D/A commutator No. 2 3) D/A range: -5V~+5V(isolated) 7.2.2.4 Network interface
1) Serial port 1: RS-485 or USB interface 2) Serial port 2: RS-485 (isolated)
3) CAN bus line: CANH, CANL (isolated)
4) Communication protocol: standard modbus protocol 7.2.2.5 Power supply parameter
1) DC: DC220V±20% or DC110V±20%
2) Auxiliary AC: station service AC220V±15%
3) Power: less than 400W 7.2.2.6 Criteria parameter
G E X - 2 0 0 0C / D g e n e r a t o r e x c i t a t i o n r e g u l a t o r m e e t s o r i s b e t t e r t h a n t e c h n i c a l r e q u i r e m e n t s o f GB/T 7409.3-1997 for large and medium synchro generator excitation system. Specific criteria parameters
are as follows:
1) CPU type: 32 bits high speed DSP chip;
2) CPU speed: maximum 150MHz;
3) Silicon controlled angle α resolution ratio: 0.0048 degree/code;
4) A/D conversion resolution ratio: 2-14, No. 16;
5) Regulation speed of control calculation: 3.3 ms;
6) Pressure regulating range: 5%~130%;
7) Pressure regulating precision: <0.5%
8 ) P h a s e s h i f t i n g r a n g e: 1 0 ~ 1 5 0 d e g r e e, m a x i m u m a n d m i n i m u m v a l u e c a n b e s e t b y procedure;
9 ) A d j u s t m e n t d i f f e r e n t i a l: s o f t w a r e r e a c t i v e d i f f e r e n t i a l , o p t i o n a l g r a d e d i f f e r e n t i a l o f p o s i t i v e a n d negative size is ±0.1%;
10) Frequency characteristic: once frequency changes by 1%, the generator terminal voltage changes not more than ±0.25% of rated value;
11) Regulation speed of adjusted value: programmable, not more than 1% per second, not less than 0.3% per second;
1 2) I n t he c on di t i on of un l oa de d r at e d vo l t a ge , w h en ge n er a t or se t s t e p i s ± 10 %, ge ne r a t or v ol t ag e overshoot is less than 30% of step quantity, oscillation number is less than 2, adjusting time is less than 5 seconds;
13) When the generator raise voltage from zero, terminal voltage overshoot is not more than 10% of rated voltage, oscillation number is less than 2, adjusting time is less than 5 seconds;
14) Working method: main and standby;
15) T hee xcitations i equipped e lectricsystem s s ystem ( tabilizeri e f PSSS),r i ts ffective requency ange s 0.1~2.5Hz. Meanwhile, set necessary protection and control circuit;
16) The annual forced exit ratio of excitation system is not more than 0.05%;
17) The e xcitations i i ystem s ls nternationalo 3 o a s trict w eveld f f nti-interference tandard, hen isturbed
by the above level, conditions of maladjustment, error adjustment, error operation and misoperation, etc.
7.3 Principal Introduction 7.3.1 Main Principal
The m fain ounctiont m f e he ricrocomputero t g i t mxcitationt v egulator f he enerator s o aintain he oltage
stability of the power generator. Meanwhile it can realize the rational reactive power distribution of units r u n n i n g i n p a r a l l e l w i t h t h e h e l p o f m i c r o c o m p u t e r e x c i t a t i o n r e g u l a t o r. I t c a n a l s o i m p r o v e t h e s t e a d y s t a b i l i z a t i o n a n d d y n a m i c s t a b i l i z a t i o n a n d p l a y a n i m p o r t a n t r o l e i n e x c i t a t i o n r e g u l a t o r. I n p u t e l e c t r i c signals of regulators are PT voltage signals and three-phase stator current flow signals from generators. DC
s i g n a l s a r e c u r r e n c y s i g n a l s f r o m g e n e r a t o r r o t o r, o u t p u t c u r r e n c y s i g n a l s f r o m r e g u l a t o r s a n d v o l t a g e s i g n a l s f r o m r e a c t i o n e q u i p m e n t . S i n g l e s o f e a c h c i r c u i t c a n b e c h a n g e d i n t o t h e o n e s a d a p t i n g t o A / D
s a m p l i n g a n d s i n g l e f i l t e r i n g c a n b e i s o l a t e d a n d m a g n i f i e d t h r o u g h i n d i v i d u a l s i g n a l d i s p o s a l a n d conversion circuit. These signals can be sent to A/D converter and modulus can be converted into digital values through program control one by one, deposited in the memorizer and used by regulators.
D e p e n d i n g o n a b o v e c o l l e c t e d d a t a , a l l i n f o r m a t i o n , e . g . r u n n i n g c o n d i t i o n o f t h e g e n e r a t o r s, d a t a o f e x c i t a t i o n s y s t e m a n d o u t p u t d a t a o f r e g u l a t o r s , e t c . c a n b e c a l c u l a t e d t h r o u g h
s o f t w a r e. F o r e x a m p l e , e ff e c t i v e v a l u e s o f t h r e e - p h a s e v o l t a g e a n d c u r r e n t , a c t i v e p o w e r P a n d r e a c t i v e
i s o l a t i o n i n t h e s w i t c h i n g q u a n t i t y o u t p u t w a y . I n t h e m e a n t i m e , r e g u l a t o rs p r o v i d e c o m m u n i c a t i o n
i n t e r f a c e s a n d c a n c o m m u n i c a t e w i t h D C S ( E C S ) s y s t e m w i t h t h e p o w e r p l a n t . T h e ex c i t a t i o n r e g u l a t o r o f G E X - 2 0 0 0 A ( B ) g e n e r a t o r h a v e 1 6 s w i t c h i n g q u a n t i t y o u t p u t a n d 1 2 s w i t c h i n g
quant ity output gall eries. The quantity of switching quantit y input and out put channels can be expanded depending on the need of users to a further extent.
Power output parts of the regulator cabinet is three-phase wholly-controlled SCR rectifier bridge or single-phase wholly (or semi)-control led bridge. In order t o guarantee that it s output DC vol tage can be a d j u s t e d c o n t i n u o u s l y a n d r e a l i z e i n v e r t e r o p e r a t i o n , t h e c o n t r o l a n g l e α s h a l l b e c h a n g e d b e t w e e n
10~ 150 degree. Wi t hin t he upper and low er l im it s, user s can set the maxi mum and mi nim um t r igger i ng
angles i t mn heP synchronous cenu. ulsei t rircuit i u n t ghe egulatort s bs sed o uarantee he uccessive reakover of various thyristors, digit control quantity can be converted into the window signal of the relevant control
angle α directly through a large-scale logic device, and cosine phase shift is adopted.
300Hz interruption control process can be used to calculate the difference of generator voltage and
r e f e r e n c e v o l t a g e . A f t e r P I D c a l c u l a t i o n , a c o n t r o l l e d v a r i a b l e c a n b e g a i n e d t h r o u g h c o m p r e h e n s i v e additional difference signal to change the conduction angle of thyristor. This is the main adjusting cycle of
t h e e x c i t a t i o n r e g u l a t o r. T h e c o r r e c t s e l e c t i o n o f P I D d a t a w i l l a f f e c t c h a r a c t e r i s t i c s o f static state and dynamic state of the regulator directly.
Protection f munctionalo t r odulee p l fd he l egulator,e l .g.o ulse oss etection, ow xcitation imitation, ver-
e x c i t a t i o n r e s t r i c t i o n , V / H z r e s t r i c t i o n a n d P T d i s c o n n e c t i o n p r o t e c t i o n , e t c . a r e a l l r e a l i z e d t h r o u g h backstage software control.
T h e p l a c e w h e r e t h e e x c i t a t i o n r e g u l a t o r i s i n s t a l l e d i s v e r y b a d a n d e l e c t r o m a g n e t i c i n t e r f e r e n c e is relatively severe. The anti-jamming capability of a microcomputer excitation regulator is very important.
T h i s re g u l a t o r h a s u n i q u e a n t i - j a m m i n g m e a s u r e . Fo r e x a m p l e , t h e c o r e p a r t o f t h e c o n t r o l p a n e l o f a regulator i e sw quippedd shields, e achitho ooubleutputi c ir o nputo electromagnetic i solationircuit s ptical r
c i r c u i t , a n d s w i t c h p o w e r i s o l a t i o n i s t a k e n a s t h e m e a s u r e f o r t h e p o w e r s u p p l y . In a d d i t i o n , a u t o m a t i c r e s e t c i r c u i t s o f h a r d w a r e a n d s o f t w a r e a r e a r r a n g e d i n p a r t i c u l a r .
When the program runs into or comes into an endless loop for being suffered from a heavy interruption
s u d d e n l y , t h i s c i r c u i t w i l l r e s e t a u t o m a t i c a l l y , m a k e s t h e p r o g r a m i m p l e m e n t f r o m t h e b e g i n n i n g , a n d recovers the normal working condition.
A n o p e r a t i o n d i s p l a y i n t e r f a c e i s d e s i g n e d i n f r o n t o f t h e r e g u l a t o r c a b i n e t f o r t h e c o m m u n i c a t i o n bet ween human and the comput er. The human-computer interface is a LED display with Chi nese menu.
Ac t u a l v a l u e s o f a l l a n a l o g q u a n t i t i e s c o l l e c t e d b y t h e c o m p u t e r c a n b e s h o w n o n t h e L E D d i s p l a y to be monitored easily by the operator. In addition, the functions like real-time status display of switching
quantity output, enforced output of switching quantity, setting of control and protection data, extraction of failure filtering data and wave display, can all be realized on the human-computer interface.
The working power of the regulator is independent and switch power is adopted. There are four kinds of o utputv : +5v a nd±12v p owersoltage mupplyb u ainf computing aoard sed; 24V p owersmplifieror upply f o r p ul s e , r e l ay a nd o pe r at i on l oo ps . Po w er i s su pp l i e d f r om du pl e x f ee di ng: o ne i s f r o m t he D C o f t h e plant, and the other is from the AC of the plant. The t wo ways of power are paral lel running through a blocking diode. If any way loses power, the regulator can still work normally.
7.3.2 Single Board Principle
As the excitation system of the synchronous generator, its reliability is very essential for the safety and stability of unit and power grid. Therefore, the system reliability shall be taken as an important content in
t h e d e s i g n o f G E X - 2 0 0 0 m i c r o c o m p u t e r e x c i t a t i o n r e g u l a t o r. Me a n w h i l e , t h e e s t a b l i s h m e n t o f a s t a b l e hardware test control platform is a reliable base for the improvement of the system.
GEX-2000 core controller is composed of the following several parts:
Power 1
Power 2
Central Processing Unit
Analog quantity proposal and inspection board of rotary diode
I/O board of switching value
Pulse enlargement board
PT/CT board
Bus bottom board
Display panel
Above several control boards (see fig. 4-4b) are inserted into a special 4U case. In order to improve the anti-jamming ability, a metal shield case is adopted. All inserts shall be rear insert type to guarantee the
u n i q u e n e s s o f s i g n a l f l o w a n d a v o i d t h e s e r i e s w i n d i n g o f s i g n a l s a n d t h e c r o s s o v e r o f s t r o n g a n d w e e k power. Advanced technical process is applied to the surface of important board card. The bottom board of
the bus is installed in the front of the case. A 240×128 dot matrix LED display is installed on the panel in front to realize real-time monitoring of running condition, and some important status indicating lights are on the front panel.
Power system
In order to improve the reliability of the system, the power supply of the system is generated by the redundancy of two circuits from the excitation transformer or rectified into AC after DC power used for the
plant is isolated by isolation transformer. Besides, it also supplies power for switches in the case together
t h r o u g h p a r a l l e l c o n n e c t i o n r u n n i n g o f d i o d e a n d D C f r o m t h e m e m o r i z e r b a t t e r y u s e d f o r t h e p l a n t . In order to improve the anti-jamming ability of the system, the system power can be divided into 3 sections
according to different functions:
1) CPU power: 5V, ±12V. Thereof, core voltage of DSP chips is 1.8V, peripheral voltage is 3.3V, and the low-voltage system guarantees the low consumption and high reliability of high speed CPU.
2) Operation power: is 24V2 and used for input and output of switching quantity. For the excitation system
o f d o u b l e c h a n n e l s , 2 4 V 2 o f t h e d o u b l e c h a n n e l s p r o v i d e o p e r a t i o n s i g n a l s t h r o u g h t h e p a r a l l e l c o n n e c t i o n o f d i o d e . T h e d i r e c t p a r a l l e l c o n n e c t i o n o f t h e t w o c h a n n e l s c a n g u a r a n t e e t h e
redundancy of 24V2 power.
3) Pulse power: 24VI, used for the pulse amplification and triggering loop.
Above power systems are independent mutually and can avoid the generation of interruptions.
Computer Processing Unit (CPU)
This is the pivot control board and we select the most popular one currently. It is composed of 32 DSP