http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Yawei Wu,Yifan Cui,Ronggang Ni,Shuxin Nie,Xinzhen Wu 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5
The performance of the initial rotor position detection of Permanent Magnet Synchronous Machines (PMSMs) at standstill depends much on the position observer. In this paper, the Extended State Observer (ESO) is compared with the traditional Proportional Integration (PI) observer adopting the rotating high frequency voltage injection algorithm, and the observer parameter design method is derived based on the bandwidth analysis of the close-loop transfer function. Experiments are carried out on a 3 kW PMSM prototype for verifications.
Modeling and Analysis of SEIG-STATCOM Systems Based on the Magnitude-Phase Dynamic Method
Wang, Haifeng,Wu, Xinzhen,You, Rui,Li, Jia The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.3
This paper proposes an analysis method based on the magnitude-phase dynamic theory for isolated power systems with static synchronous compensators (STATCOMs). The stability margin of an isolated power system is greatly reduced when a load is connected, due to the disadvantageous features of the self-excited induction generators (SEIGs). To analyze the control process for system stability and to grasp the dynamic characteristics in different timescales, the relationships between the active/reactive components and the phase/magnitude of the STATCOM output voltage are derived in the natural reference frame based on the magnitude/phase dynamic theory. Then STATCOM equivalent mechanical models in both the voltage time scale and the current time scale are built. The proportional coefficients and the integral coefficients of the control process are converted into damping coefficients, inertia coefficients and stiffness coefficients so that analyzing its controls, dynamic response characteristics as well as impacts on the system operations are easier. The effectiveness of the proposed analysis method is verified by simulation and experimental results.
Modeling and Analysis of SEIG-STATCOM Systems Based on the Magnitude-Phase Dynamic Method
Haifeng Wang,Xinzhen Wu,Rui You,Jia Li 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.3
This paper proposes an analysis method based on the magnitude-phase dynamic theory for isolated power systems with static synchronous compensators (STATCOMs). The stability margin of an isolated power system is greatly reduced when a load is connected, due to the disadvantageous features of the self-excited induction generators (SEIGs). To analyze the control process for system stability and to grasp the dynamic characteristics in different timescales, the relationships between the active/reactive components and the phase/magnitude of the STATCOM output voltage are derived in the natural reference frame based on the magnitude/phase dynamic theory. Then STATCOM equivalent mechanical models in both the voltage time scale and the current time scale are built. The proportional coefficients and the integral coefficients of the control process are converted into damping coefficients, inertia coefficients and stiffness coefficients so that analyzing its controls, dynamic response characteristics as well as impacts on the system operations are easier. The effectiveness of the proposed analysis method is verified by simulation and experimental results.
Xiaoqin Zheng,Wen Zhang,Xinzhen Wu,Ronggang Ni 한국자기학회 2019 Journal of Magnetics Vol.24 No.1
Concentric winding has been widely used in small capacity AC motors due to its excellent performance. In this paper, a numerical calculation method based on the magnetic vector potential is proposed to calculate the stator end leakage reactance of concentric winding. In this case, the basic unit of numerical calculation becomes the coil group rather than the coil since concentric windings have different coil sizes. The calculated stator end leakage reactance of a prototype three-phase permanent magnet machine with concentric winding is validated using the finite element method. Compared to 3D electromagnetic field calculation, the proposed method does not require a complex modeling process and is therefore highly efficient computationally, requiring only a fraction of the calculation time.
You, Rui,Chai, Jianyun,Sun, Xudong,Bi, Daqiang,Wu, Xinzhen The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.1
In the variable speed Wind Turbine based on ElectroMagnetic Coupler (WT-EMC), a synchronous generator is coupled directly to the grid. Therefore, like conventional power plants, WT-EMC is able to inherently support grid frequency. However, due to the reduced inertia of the synchronous generator, WT-EMC is expected to be controlled to increase its output power in response to a grid frequency drop to support grid frequency. Similar to the grid frequency support control of Type 3 or Type 4 wind turbine, inertial control and droop control can be used to calculate the WT-EMC additional output power reference according to the synchronous generator speed. In this paper, an experimental platform is built to study the grid frequency support from WT-EMC with inertial control and droop control. Two synchronous generators, driven by two induction motors controlled by two converters, are used to emulate the synchronous generators in conventional power plants and in WT-EMCs respectively. The effectiveness of the grid frequency support from WT-EMC with inertial control and droop control responding to a grid frequency drop is validated by experimental results. The selection of the grid frequency support controller and its gain for WT-EMC is analyzed briefly.
Rui You,Jianyun Chai,Xudong Sun,Daqiang Bi,Xinzhen Wu 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.1
In the variable speed Wind Turbine based on ElectroMagnetic Coupler (WT-EMC), a synchronous generator is coupled directly to the grid. Therefore, like conventional power plants, WT-EMC is able to inherently support grid frequency. However, due to the reduced inertia of the synchronous generator, WT-EMC is expected to be controlled to increase its output power in response to a grid frequency drop to support grid frequency. Similar to the grid frequency support control of Type 3 or Type 4 wind turbine, inertial control and droop control can be used to calculate the WT-EMC additional output power reference according to the synchronous generator speed. In this paper, an experimental platform is built to study the grid frequency support from WT-EMC with inertial control and droop control. Two synchronous generators, driven by two induction motors controlled by two converters, are used to emulate the synchronous generators in conventional power plants and in WT-EMCs respectively. The effectiveness of the grid frequency support from WT-EMC with inertial control and droop control responding to a grid frequency drop is validated by experimental results. The selection of the grid frequency support controller and its gain for WT-EMC is analyzed briefly.