Algorithm for asynchronous damping coefficient. The numerical simulation of the equivalent asynchronous damping coefficient obtained by the algorithm can accurately describe the effect of the damper winding on the stability of the power system. In the past, when people were engaged in power system stability analysis research or controller design, in order to save computational memory and avoid disasters, the power system was often simplified and reduced. The usual practice is to consider the effect of the damper windings on some generator sets, and consider the simplified model to achieve the purpose of reducing the order. It is assumed that during the low-frequency oscillation of the power system, the current induced in the damper winding is still negligibly small, so the damper winding can be completely ignored in the system model. If the damping strength of the generator set is sensitive to the dominant oscillation mode or unstable oscillation mode of the power system, simply ignoring the damper winding of the unit and discarding the asynchronous damping effect of the unit may identify a stable power system as not stable. The conclusion of ring stability forces people to take measures to improve stability and cause unnecessary economic losses. Aiming at this situation, this paper uses the eigenvalue and its sensitivity analysis technique to give the algorithm of the equivalent asynchronous damping coefficient which keeps the real part of the eigenvalue of the sensitive oscillation mode before and after the generator is reduced, and obtains the corresponding example through the example. in conclusion. The higher the model order of the generator set, the more detailed the description of the generator set, but the more computer memory is used, the slower the analysis speed is. Therefore, the generator transient reduction model has a fixed sub-transient potential change model as the original model, and the transient potential variation model without generator damper winding is used as the reduced-order model, and the equivalent asynchronous damping coefficient algorithm is studied. . Considering the damper winding, the generator's cross-axis transient potential is divided into 1 and the incremental differential equation of the genset slip is as follows, which is the mechanical damping coefficient of the unit, and the meaning of other symbols. The full power system linearized differential equation 2 can be obtained in the following form, where 4 is a coefficient matrix containing parameters such as and 7. In order to reduce the order of the matrix 4, only the change of the transient potential of the generator's cross-axis is considered. The incremental differential equation of the generator set slip is as follows, which is the comprehensive damping coefficient of the generator set. Similarly, the full-power system linearized differential equation of the following form can be obtained, where 1 is a coefficient matrix of parameters including, and coincidence. For the comprehensive damping coefficient of the generator set, the following relationship is established, and the equivalent asynchronous damping coefficient of the generator damper winding is considered. Sexual research analysis results in bias. Firstly, the unit's comprehensive damping coefficient is obtained, and then the mechanical damping coefficient is subtracted to obtain the equivalent asynchronous damping coefficient. Since the damping of each unit is mainly affected by the damping of the unit's mechanical oscillation mode, and has little effect on the oscillation frequency, the equivalent asynchronous damping coefficient can be obtained by the following calculation steps. 1 Find the eigenvalues ​​and eigenvectors of the unreduced power system according to Equation 2, and then find the sensitivity of the damper coefficient of the unit to all the conjugate complex eigenvalues ​​of the system. Among them, the third 共有 conjugate complex eigenvalue real part of the gold system shared claws. For the conjugate complex eigenvalues, the first is the left and right normalized eigenvectors of the first pair of conjugate complex eigenvalues, and 0 is the seventh set of reduced-stage unit damping coefficient system-wide total reduction unit. According to the above sensitivity value, the conjugate complex eigenvalue corresponding to the first step-down unit is identified, and the actual part is recorded as 1. Take the initial damping coefficient of the reduced-stage unit with an initial value of 1=, lean to zero, set the number of iterations to be =0, and give the calculation accuracy as safety. Find the eigenvalues ​​and eigenvectors of the reduced-order power system according to Equation 4, and then find the sensitivity of the conjugate complex eigenvalues ​​of the system to the damping coefficient of the reduced-order unit to identify the conjugate complex eigenvalues ​​of the first reduced-order unit. The Ministry recorded as = exhausted. The value is configured for eigenvalues. The correction coefficient of the comprehensive damping coefficient of the first stage reduction unit is 4, and if there is 5, the calculation result is output and the iterative calculation is stopped. Otherwise, let left +1=, according to the modified comprehensive damping coefficient correction matrix, go to step 3. And the operating parameter standard value. The node number machine is a 12-thrank small unit equivalent machine, the node 42 machine is 5 sets of 100, the Jia unit is equal machine, the node 53 machine is 3 sets of 100, and the Jia unit is equal. Node 13 carries a load. For a brief explanation, all loads are considered at constant impedance and all generator stator winding resistance and mechanical damping factor are taken to be zero. The meaning of the adjustment system frame and parameters is detailed. The No. 1 machine is a fixed excitation; the excitation adjustment system of the No. 23 machine is the same, and the parameters are as follows: The No. 13 machine is a turbo generator. The corresponding single-machine speed control system is the same, the parameters are as follows: No. 1 machine has no intermediate reheat link. The single-machine generator parameter of the equal-value machine is the relative power angle curve stability measure to prevent the system from disintegrating. 5. Obviously, this conclusion will result in Unnecessary economic losses. Comparison 42 shows the role of the damper winding in the process of large disturbances when using the generator reduction model. 1 The generator reduction model should be used with caution. As long as the computer hardware conditions permit, the reduced order model should be avoided. In the case of a reduced-generator model of a genset without damper windings, ignoring the asynchronous damping effect of the damper windings may lead to erroneous conclusions to the research or analysis results, which will cause unnecessary economic losses. The eigenvalue and sensitivity analysis technique of 2 meters is used to give the equivalent asynchronous damping coefficient algorithm for keeping the real part of the eigenvalue of the sensitive oscillation mode before and after the generator is reduced. As an example, the algorithm can better account for the effect of the damper winding on the stability of the power system. 3.1 Generator model reduction and equivalent asynchronous damping coefficient analysis and calculation situation 1 The generator adopts the formula 1 model, and the mechanical oscillation mode corresponding to the No. 3 machine has the characteristic value of 42±12.7365, respectively. The value is not listed, indicating that the system is stable with small interference in the mode of operation under study. Case 2 The generator adopts the reduced-order model of Equation 2 and does not count the asynchronous damping effect. The characteristic values ​​of the mechanical oscillation modes corresponding to the No. 13 machine are respectively unstable at +1.0919±12.275. In order to improve the stability of the system, this conclusion forces people to install additional controllers on the relevant generator sets, which will eventually result in waste of investment. Case 3 The generator adopts the reduced-order model of Equation 2 and takes into account the asynchronous damping effect of the damper winding. The equivalent asynchronous damping coefficient of the equivalent machine of the 13th equalizer is 1.332 14.1373 and 7.3569, respectively, corresponding to the mechanical oscillation mode. The eigenvalue is ±6.8307. Compared with case 1, it can be seen that the equivalent asynchronous damping coefficient algorithm proposed in this paper can better preserve the asynchronous damping effect of the damper winding while using the reduced order model, so as to maintain the stability better. The correctness of the analysis results. It should be noted that the above equivalent asynchronous damping coefficient is only obtained for the type of operation. If multiple modes of operation are involved, multiple equivalent asynchronous damping coefficients corresponding to each mode of operation must be calculated and used. 3.2 System simulation calculation under large disturbances In the above system, the branch between nodes 2 and 3 is composed of two identical parameters, and the phase permanent short-circuit fault occurs on the line side of the return line node 3. When the fault is removed, 24 corresponds to the above situation 13.5 is the case where the fault is removed in case 2, and the load of the No. 1 node 40 and the 90 units are cut. In the middle, the vertical axis is the relative power angle and the unit is . The horizontal axis is time in units of 3. It can be seen from 2 that the units in the system can keep running synchronously. But the swing, and eventually lost synchronization. Under this conclusion, it is necessary to take an anti-accident Yu Yaonan. Dynamic power system at the beginning. Beijiao Water Power Press, 1985 Xi'an Jiaotong University. Power system calculations. Beijing Water and Electric Power Press, 1978. Responsible editor Zhang Zhongshi,
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