Advanced Hybrid SFA/EMTP Simulator for Seamless Integration of Power Systems Dynamics and EMT Transients

预计到2050年，世界总电能的70%将来自风能和太阳能。这种不断增长的基于逆变器的发电(IBG)正在削弱传统大型水力发电和火电同步发电机的等效机械惯量，并削弱电力系统通过正常系统动态的能力。 传统的电力系统稳态和动态运行分析软件，如潮流、暂态和动态稳定、电压和频率稳定等，都是基于电力系统的相量分析和求解发电机的机电方程。这种方法在高机械惯量的假设下是有效的，使系统时间常数对于故障和切换动作为毫秒量级，或者对于负荷/发电调速器控制为秒量级。然而，随着IBG的穿透和系统机械惯量的减小，稳态运行中的扰动会引起更大的角度、电压和频率偏差，系统调节器的限制和系统继电保护的整定将需要修改。另一方面，IBG子系统和其他与交流电网相互作用的电力电子设备的解决方案通常是使用工作在微秒范围内的EMT软件来完成的。 目前正在作出巨大努力，将相量解决方案与EMT解决方案相结合。然而，由于两个不同性质、具有不同求解方法和不同集成步骤的系统之间的接口存在概念和数值上的困难，因此需要对这些问题进行基础研究，以开发能够无缝集成使用相量或EMT方法建模的任意数量的子系统的通用仿真软件。 这项提案中工作的主要动机是找到更好的解决相量和EMT系统接口问题的方案，以改进或消除目前的限制。我们希望开发通用的解决方案，可以无缝地连接表示为相量或EMT的任何数量的子系统，而不必使用迭代、简化的等价物或缓冲区。为了实现这些目标，必须解决一些数量和基本概念问题。NSERC发现基金是加拿大的一笔适当拨款，用于支持实现这些突破所需的基础研究。 随着工业从基本的60赫兹系统过渡到混合系统，这些解决方案的影响在电力系统社区中影响深远。

It is expected that for the year 2050, 70% of the total electrical energy in the world will be based on wind and solar. This continuously increasing amount of Inverter Based Generation (IBG) is weakening the equivalent mechanical inertia of traditional large hydro and thermal synchronous generators and the ability of the power system to ride through normal system dynamics. Traditional power systems analysis software for steady state and dynamic system operation, such as power flow, transient and dynamic stability, and voltage and frequency stability, are based on phasor analysis for the electrical system and solving the electromechanical equations for the generators. This approach is valid under the assumption of high mechanical inertia that brings the system time constants to the order of the milliseconds for faults and switching actions, or seconds for load/generation governor control. However, with the penetration of IBGs and the decrease of the system's mechanical inertia, the disturbances in the steady state operation will give rise to stronger deviations in angle, voltage, and frequency, and the limits imposed by the system regulators and the settings of the system relays will need revisions. On the other hand, the solution of the IBG subsystems and other power electronics equipment that interact with the AC grid is normally done with EMT software that works in the range of the microseconds. Strong efforts are currently being made to integrate phasor solutions with EMT solutions. However, because of the conceptual and numerical difficulties involved in interfacing two systems of different nature, with different solution methods, and different integration steps, fundamental research into these issues is needed for developing general purpose simulation software that can seamlessly integrate an arbitrary number of subsystems modelled with phasor or EMT methods. The main motivation of the work in this proposal is to find better solutions to the issues of interfacing phasor and EMT systems that improve on or remove the current limitations. We want to develop general solutions that can join seamlessly any number of subsystems represented as phasor or EMT, without having to use iterations, reduced equivalents, or buffer zones. A number of numerical and fundamental conceptual issues have to be addressed to achieve these objectives. The NSERC Discovery grant is the apropriate grant in Canada to supports the fundamental research needed to achieve these breakthroughs. The impact of these solutions is far reaching in the power systems community as industry makes its transition from a fundamentally 60 Hz system to a hybrid system.