次同步振荡中暂态能量流与电功率和阻尼转矩的关系

Relationship Between Transient Energy Flow,Electric Power and Damping Torque in Subsynchronous Oscillation

暂态能量流法是一种新的振荡分析方法,可用于多种振荡的扰动源定位和阻尼评估。文中进一步研究了其在次同步振荡中的物理意义。推导了暂态能量流与次同步功率、超同步功率之间的关系,暂态能量流的能流功率正比于超同步功率和次同步功率之差。在含串补的次同步谐振系统中,电阻可能消耗或产生暂态能量,产生暂态能量时即为负阻尼,电感和电容表现为零阻尼,但会通过改变线路电流而极大地影响电阻的阻尼特性。通过比较暂态能量流与电气子系统阻尼转矩系数,验证了上述推导的合理性。最后,在不同算例中的仿真结果验证了结论的有效性。

The transient energy flow method is a new method of oscillation analysis, which can be applied to the oscillation source location and damping assessment. This paper further studies its physical significance in subsynchronous oscillation. The relationship between transient energy flow, subsynehronous power and supersynchronous power is deduced. The power of energy flow is proportional to the difference between supersynchronous power and subsynchronous power, In a subsynchronous resonant system with series compensation equipment, the resistance may consume or generate transient energy, which is negative damping when the transient energy is generated. The inductance and capacitance are zero damping, but can greatly affect the damping characteristics of resistance by changing the line current. By comparing transient energy damping torque coefficient of the electrical subsystem, the rationality of above derivation is verified. Finally, the simulation results in different examples verify the validity of the conclusions.