Method and system for correlating hydro-turbine governing system control parameters and oscillation characteristics

A system for correlating control parameters and oscillation characteristics of a hydro-turbine governing system hydro-turbine governing system, comprising:

• a memory, storing at least one module;
• and
• a processor, coupled to the memory, wherein the processor is configured to execute;
• a building module of a hydro-turbine governing system state space model to build the hydro-turbine governing system state space model;
• a dominant eigenvalue acquisition module to calculate an eigenvalue, a zero point and a pole of a state matrix in the hydro-turbine governing system state space model, and taking a pole which is the closest to an imaginary axis and has no zero point in a preset distance as a dominant eigenvalue;
• a determining module of an oscillation characteristic region of the hydro-turbine governing system to determine the oscillation characteristic region of the hydro-turbine governing system in a complex plane based on the dominant eigenvalue;
• an acquisition module of a system control parameter stability domain to convert the hydro-turbine governing system state space model into a transfer function model, extract a characteristic equation of the transfer function model, and obtain the system control parameter stability domain based on a Hurwitz stability criterion;
• a system control parameter stability domain division module to calculate the dominant eigenvalues corresponding to the different control parameters in the system control parameter stability domain, classify the control parameters in the system control parameter stability domain according to the oscillation characteristic region of the hydro-turbine governing system of the complex plane where the dominant eigenvalue is located, and divide the oscillation characteristic region of the hydro-turbine governing system in the system control parameter stability domain;
• where a horizontal axis of the system control parameter stability domain is Kp, and a vertical axis thereof is KI:
• Kp is a proportional coefficient of a PID (Proportional-Integral-Derivative) speed regulator in the hydro-turbine governing system;
• KI is an integral coefficient of the PID speed regulator in the hydro-turbine governing system;
• a method for dividing the oscillation characteristic region of the hydro-turbine governing system is:
• using an imaginary part of the dominant eigenvalue to determine a system oscillation frequency, and dividing the complex plane into a no-oscillation region, a 0 Hz to 0.01 Hz oscillation region, an ultra-low frequency oscillation region, and an oscillation region above 0.1 Hz;
• a real part of the dominant eigenvalue is used to determine a system attenuation rate, and the ultra-low frequency oscillation region in the complex plane is divided into an ultra-low frequency oscillation safe region and an ultra-low frequency oscillation risk region;
• if the real part is less than or equal to −0.07, the ultra-low frequency oscillation region is divided into the ultra-low frequency oscillation safe region, otherwise the ultra-low frequency oscillation region is divided into the ultra-low frequency oscillation risk region,
• wherein the processor is further configured to adjust a plurality of turbine control parameters which includes PID values of Kp and KI on a turbine speed regulator of a water turbine based on the control parameters within the ultra-low frequency oscillation safe region, and controlling the water turbine included in the governing system based on the turbine control parameters.