EBOOK Power Generation Operation and Control (Allen J. Wood) Hoạt động và Kiểm soát Năng lượng (Allen J. Wood)

... during peak and emergency conditions, performing coordination studies that include source and low side protection equipment, and expected transformer size and winding configuration (ANSI=IEEE, ... maintenance and cost advantages found with power fuses Protection and control devices, circuit breakers, and station batteries are required The overcurrent relays are a small part of...

Ngày tải lên: 21/03/2014, 12:08

... (1 ) the real power is below a negative pre-set threshold SET_1, (2 ) the steam valve or a differential pressure switch is closed (either condition indicating the removal of the prime-mover), (3 ) ... computation as shown in Eq (2 .8) would be performed ANSI=IEEE standard limits are 1.05 pu for generators and 1.05 for transformers (on transformer secondary base, at rated load,...

Ngày tải lên: 21/03/2014, 12:08

... distance A B Rab Rba C Rbc Rcb (b) FIGURE 3.8 Three-zone step distance relaying to protect 100% of a line and backup the neighboring line (From Horowitz, S.H and Phadke, A.G., Power System Relaying, ... multiphase fault between phases x and y, Ex À Ey ¼ Z1 Ix À Iy (3 :1) where x and y can be a, b, or c and Z1 is the positive sequence impedance between the relay location and t...

Ngày tải lên: 21/03/2014, 12:08

... and are available under two similar standards: (a) Sonet (synchronous optical networks) is the American System under ANSI T1.105 and Bellcore GR standards; (b) synchronous digital hierarchy (SDH) ... bandwidth, usually expressed in bits per second (BPS), latency in data transmission, reliability, and communication error handling Presently, electrical utilities use a combination of ana...

Ngày tải lên: 21/03/2014, 12:08

... t2 ð t1 v(t)dt ¼ R t2 ð i(t)dt þ L(i(t2 ) À i(t1 )) (5 :33) t1 t2 ð v(t)dt ¼ R i(t)dt þ L(i(t2 ) À i(t1 )) (5 :34) t1 R and L are given by " # (vkþ1 þ vk )(ikþ2 À ikþ1 ) À (vkþ2 þ vkþ1 )(ikþ1 À ... Eq (5 .38) t2 ð v(t)dt À L[i(t2 ) À i(t1 )] ¼ L(t2 ) À L(t1 ) (5 :39) t1 gives L(t2 ) À L(t1 ) ¼ T [v(t2 ) þ v(t1 )] À L[i(t2 ) À i(t1 )] (5 :40) or T Lkþ1 ¼ Lk þ [vkþ1 þ vk ] À L[...

Ngày tải lên: 21/03/2014, 12:08

... good ( ‘A’’) block signal and questionable ( ‘B’’) block signal The good block signal is shown as one that blocks (comes ‘‘on’’) within a fraction of a cycle after the fault is detected and unblocks ... classifying operations as good (A) or questionable (B) as shown in Fig 6.2 The first fault current waveform (upper left) is classified as A because it is sinusoidal in nature and cle...

Ngày tải lên: 21/03/2014, 12:08

... understanding of the electric power industry’s practices with regard to system stability Power system stability was first recognized as an important problem in the 1920s (Steinmetz, 1920; Evans and ... Design and Operation For reliable service, a power system must remain intact and be capable of withstanding a wide variety of disturbances Owing to economic and technical limitat...

Ngày tải lên: 21/03/2014, 12:08

... tc2 t (s) t (s) (a) (b) FIGURE 8.7 Rotor response (defined by the swing equation) superimposed on the power angle curve for an unstable case (A1 ¼ A2) and the rotor angle reaches a maximum and recovers ... equation as given by Eq (8 .7) and interchanging per unit power for torque d2 d v (Pm À Pe ) ¼ dt 2H (8 :10) Multiplying both sides by 2d=dt and integrating gives  d  ð dd...

Ngày tải lên: 21/03/2014, 12:08

... exponential terms of the form elj t and e(lk þll )t : xi (t) ¼ n X j¼1 uij zj0 e lj t þ n X j¼1 uij " n n XX k¼1 l¼1 C j kl zk zl0 e(lk þll )t lk þ ll À lj # (9 :2) lk, ll, and lj are the system modes, ... J., and Fortin, S., A minimal realization approach to reduced-order modeling and modal analysis for power system response signals, IEEE Trans Power Systems, 8(3 ), 1020–102...

Ngày tải lên: 21/03/2014, 12:08

... including real (P) and reactive (Q) power dynamics, are dx ¼ Ps (V ) À P, P ¼ xPt (V ) dt dy ¼ Qs (V ) À Q, Q ¼ yQ t (V ) Tq dt Q t (V ) ¼ V b , Pt (V ) ¼ V a , Ps (V ) ¼ Po V a ; Tp Qs (V ) ¼ Q o ... reactive power demand (or injection) at the receiving end 0.2 while maintaining the real power and the sending end voltage constant The relation between the receiv(1) (2 ) ing end v...

Ngày tải lên: 21/03/2014, 12:08

... and Technological Information and the Academy of Sciences of the USSR (in Russia) Criteria of Stability of Electric Power Systems Electric Technology and Electric Power Series, Moscow, 1971 (in ... general structure given by _ x (t ) ¼ f (t, x(t)) (1 1:6) The system described by Eq (1 1.6) is said to be autonomous if f (t, x(t))  f (x), i.e., independent of t and is s...

Ngày tải lên: 21/03/2014, 12:08

... Francis Group, LLC P Predisturbance electrical power Pm Postdisturbance During fault d ′o p− d ′o (a) d ′o p− d ′ o p δ Δw δ (b) FIGURE 12.4 (a) Power angle curve and equal area criterion Dark shading ... characteristics of the electrical power system, the prime mover and prime mover controls, and the energy supply system (boiler) 250 Relative angle (deg.) without TEB 200 150 with...

Ngày tải lên: 21/03/2014, 12:08

... current (HVDC) systems (Kundur, 1994) and power electronic (PE) devices The latter includes static VAr compensators (SVC) (IEEE Transactions, February 1994) and a number of newer devices (TCSC, ... s d H ¼ 5:48 Â 10À9 J (RPM)2 MW-s=MVA MVA rating Sometimes, the mechanical power and electrical power are used in this model instead of the corresponding torques Since power equals to...

Ngày tải lên: 21/03/2014, 12:08

... like m(t) ¼ M exp(Àst) cos(vt þ u) (1 4:2) Here (s, v) are mode parameters that denote the frequency and damping of a mode, and (M, u) are mode shape parameters that denote the strength and phase ... Frequency (Hz) 10:52:19 (Brake insertion) 14:52:37 ( John Day–Marion) 15:18 (Ringing) 15:42:03 (Keeler–Allston) 15:45 (Ringing) 15:47:40 (Oscillation start) 15:48:50 (Oscillation fini...

Ngày tải lên: 21/03/2014, 12:08

... reliability and security of electric power systems The benchmark paper by Tom Dy Liacco introduced the concept of the preventive (normal), emergency, and restorative operating states and their ... capability (ATC) becomes stronger in the restructured industry References Anderson, P.M and Bose, A., A probabilistic approach to power system stability analysis, IEEE Transactions on...

Ngày tải lên: 21/03/2014, 12:08