The Definition of Power Grid Strength and Its Calculation Methods for Power Systems with High Proportion Nonsynchronous-Machine Sources

This paper studies the definition and calculation method of power grid strength in environment high-proportion nonsynchronous-machine sources, focusing on effect sources voltage support frequency strength. By dividing into four types, equivalent circuits each type under normal state fault are derived, respectively. Based Thevenin impedance connected device, is given, new meaning single-infeed short-circuit ratio multi-infeed context high proportion presented. initial change rate steady-state deviation any node maximum expected active disturbance, inertia lifting factor decreasing defined, respectively, to describe contribution strength, methods given.