Abstract: A method to incorporate the steady-state model of the generalized power flow controller into a Newton-Raphson power flow algorithm adopts a flexible steady-state model of the generalized power flow controller, which can be applied to calculate the power flow solution of a power grid embedded with STATCOM, UPFC, GUPFC and the generalized power flow controller in a single framework. The method only incorporates the control variables of the shunt voltage sourced converter into the state vector of the Newton-Raphson power flow algorithm. The increment of the state variables due to incorporating the generalized power flow controller is less than the prior art. Further, the method can preserve the quadratic convergence characteristic of the Newton-Raphson power flow algorithm after embedding the generalized power flow controller into a power grid.

Abstract: A method to incorporate the steady-state model of the generalized power flow controller into a Newton-Raphson power flow algorithm is disclosed. The disclosed method adopts a flexible steady-state model of the generalized power flow controller, which can be applied to calculate the power flow solution of a power grid embedded with STATCOM, UPFC, GUPFC and the generalized power flow controller in a single framework. The disclosed method only incorporates the control variables of the shunt voltage sourced converter into the state vector of Newton-Raphson power flow algorithm. The increment of state variables due to incorporating the generalized power flow controller is less than the prior art. Further, the method can preserve the quadratic convergence characteristic of the Newton-Raphson power flow algorithm after embedding the generalized power flow controller into a power grid.

Abstract: Power flow models of Interline Power Flow Controllers (IPFC) for large-scale power systems are studied, in details. Mathematical models of the IPFC, using the d-q axis decompositions of control parameters are derived. In this framework, for each IPFC, only two control parameters are added to the unknown vector in the iteration formula and the quadratic convergence characteristic is preserved. Simulations results from several practical large-scale power systems embedded with multiple Convertible Static Compensators (CSCs) demonstrate the effectiveness of the proposed models. Comparisons with existing models are made to elucidate the performance of the convergence.

Abstract: A method for calculating power flow solution of a power transmission network with unified power flow controllers is adapted to calculate the power flow on a large-scale power transmission network. The unified power flow controller has a series transformer, a series converter, a direct current coupling capacitor, a shunt converter, and a series transformer. The shunt transformer is connected electrically to a sending-end bus. The series transformer is connected electrically to the sending-end bus and a receiving-end bus. The unified power flow controller is represented by equivalent active and reactive loads on the sending-end and receiving-end buses of the power transmission network.

Abstract: Power flow models of Interline Power Flow Controllers (IPFC) for large-scale power systems are studied, in details. Mathematical models of the IPFC, using the d-q axis decompositions of control parameters are derived. In this framework, for each IPFC, only two control parameters are added to the unknown vector in the iteration formula and the quadratic convergence characteristic is preserved. Simulations results from several practical large-scale power systems embedded with multiple Convertible Static Compensators (CSCs) demonstrate the effectiveness of the proposed models. Comparisons with existing models are made to elucidate the performance of the convergence.

Abstract: The power flow model of the multiterminal voltage-source converter-based high voltage DC (M-VSC-HVDC) transmission system for large-scale power systems is studied. The mathematical model is derived using the d-q axis decomposition of HVDC's control parameter. The developed model can be applied to all existing shunt voltage-source converter (VSC) based controllers, including Static Synchronous Compensator (STATCOM), point-to-point HVDC system, back-to-back HVDC system and multiterminal HVDC system. A unified procedure is developed for incorporating the proposed model into the conventional Newton-Raphson power flow solver. The IEEE 300-bus test system embedded with multiple HVDC transmission systems under different configurations are investigated. Simulation results reveal that the proposed model is effective and accuracy in meeting various control objectives.

Abstract: A method for calculating power flow solution of a power transmission network with unified power flow controllers is adapted to calculate the power flow on a large-scale power transmission network. The unified power flow controller has a series transformer, a series converter, a direct current coupling capacitor, a shunt converter, and a series transformer. The shunt transformer is connected electrically to a sending-end bus. The series transformer is connected electrically to the sending-end bus and a receiving-end bus. The unified power flow controller is represented by equivalent active and reactive loads on the sending-end and receiving-end buses of the power transmission network.

Abstract: Given the current operating condition at each bus from real-time database, from the short-term load forecast, or from near-term generation dispatch, we present a method for real-time contingency prediction and selection in current energy management systems. This method can be applied to contingency prediction and selection for the near-term power system in terms of load margins to collapse and of the bus voltage magnitudes. The propose algorithm uses only two tangent vectors of power flow solutions and curve fitting based techniques to perform look-ahead load margin and voltage magnitude simultaneously. Therefore, it can overcome the traditional snap-shot contingency analysis methods. Simulations are performed on IEEE 57 and 118-bus test systems to demonstrate the feasibility of this method.