An intelligent power factor correction scheme is presented for three phase low power factor loads. This new scheme is able to perform individual phase sensing of parameters by monitoring at all times to sense a change...An intelligent power factor correction scheme is presented for three phase low power factor loads. This new scheme is able to perform individual phase sensing of parameters by monitoring at all times to sense a change in system parameters and affects individual phase correction by applying the exact amount of reactive components needed for each phase, and can also reduce negative sequence current caused by the load to improve system balance. An optimization criterion is used for the proper calculation of reactive power steps in a power compensation installation of capacitor banks. The criterion is enabled by sampling measurements performed on the electrical plant examined within specific interval of time.展开更多
When private electric vehicles(EVs),which will be the main part of the EVs’cluster in the future,are plugged in power system by single phase power line,can result to three-phase unbalance problem of distribution netw...When private electric vehicles(EVs),which will be the main part of the EVs’cluster in the future,are plugged in power system by single phase power line,can result to three-phase unbalance problem of distribution network.In this work,a phased-controlled coordinated charging method was put forward to solve this problem.Firstly,the impacts of charging load to distribution network was analyzed based on the equivalent circuit;and then an architecture of the control method and its corresponding optimal control model were introduced.The optimal model is a multi-objective optimization model,which includes minimizing load variance of each phase and minimizing the power asymmetrical degree of three-phase load;lastly,three scenarios considering balance and unbalance cases were envisioned to verify the reasonableness of this control method based on IEEE-37 distribution network.Results show that the phased-controlled coordinated charging method can minimize the load variance as well as the negative sequence current.展开更多
文摘An intelligent power factor correction scheme is presented for three phase low power factor loads. This new scheme is able to perform individual phase sensing of parameters by monitoring at all times to sense a change in system parameters and affects individual phase correction by applying the exact amount of reactive components needed for each phase, and can also reduce negative sequence current caused by the load to improve system balance. An optimization criterion is used for the proper calculation of reactive power steps in a power compensation installation of capacitor banks. The criterion is enabled by sampling measurements performed on the electrical plant examined within specific interval of time.
基金This work was supported by the national high technology research and development program of China(863 Program)(No.2011AA05A109).
文摘When private electric vehicles(EVs),which will be the main part of the EVs’cluster in the future,are plugged in power system by single phase power line,can result to three-phase unbalance problem of distribution network.In this work,a phased-controlled coordinated charging method was put forward to solve this problem.Firstly,the impacts of charging load to distribution network was analyzed based on the equivalent circuit;and then an architecture of the control method and its corresponding optimal control model were introduced.The optimal model is a multi-objective optimization model,which includes minimizing load variance of each phase and minimizing the power asymmetrical degree of three-phase load;lastly,three scenarios considering balance and unbalance cases were envisioned to verify the reasonableness of this control method based on IEEE-37 distribution network.Results show that the phased-controlled coordinated charging method can minimize the load variance as well as the negative sequence current.