基于模态的发电机组转动惯量参数辨识仿真

Identification and Simulation of Moment of Inertia Parameters of Generator Set Based on Mode

汽轮发电机组是一个动态时变系统,对其转动惯量参数辨识效果将直接影响到系统的控制性能,针对现有方法收敛性差与辨识波动等问题,提出了基于模态自适应的转动惯量参数辨识方法。方法首先建立发电机组转动惯量数学模型,为避免刚体结构外形、质量散布特性等因素影响,引入惯量矩变换。然后为改善辨识的主观性,将分析信号采取时域划分,根据发电机组的负载扰动变化,分析得到多阶模态下对应的转动惯量与电磁功率模型。最后,为了增强转动惯量参数辨识受扰动影响,设计参数自适应律,积分项控制基准时间之前的参数偏差,比例项控制基准时间之后的参数偏差,结合扰动观测,提高自适应收敛效果。通过仿真,充分验证了基于模态自适应方法能够快速、准确辨识出动态变化的发电机组转动惯量参数,并且具有良好的系统稳定性。

Turbo generator is a dynamic time-varying system,the identification effect of its moment of inertia parameters can directly affect the control performance of the system.Aiming at the problems of poor convergence and identification fluctuation of the existing methods,the identification method of moment of inertia parameters based on mode adaptive is proposed.In order to avoid the influence of rigid body structure shape,mass dispersion and other factors,the moment of inertia transformation was introduced.Then,in order to improve the subjectivity of identification,the analysis signals were taken the time domain dividsion.According to the load disturbance changes of the generator set,the corresponding moment of inertia and electromagnetic power model were obtained under multi-order mode.Finally,in order to enhance the influence of disturbance on the parameter identification of moment of inertia,the parameter adaptive law was designed.The parameter deviation before the reference time was controlled with integral term,and the parameter deviation after the reference time was controlled with the proportional term.Combined with disturbance observation,the effect of adaptive convergence was improved.The simulation experiment fully verified that the modal adaptive method can quickly and accurately identify the dynamic parameters of the generator’s moment of inertia,and has good system stability.