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Zhu N.,China EPRI Science and Technology Co. | Bai X.,China Electric Power Research Institute | Dong W.,China Electric Power Research Institute | Zhou Z.,State Grid Electric Power Research Institute of China
Dianwang Jishu/Power System Technology | Year: 2013

The research on DC-side voltage of active power filter (APF) are focused on how to implement the stable control of the voltage, and the minimum value of DC-side voltage of APF, by which the conditions could be met, is seldom researched. Allusion to the concrete setting of DC-side voltage of APF, referencing to the concept of voltage utilization ratio for inverters the DC-side voltage of APF under triangular PWM control and that under space vector pulse width modulation (SVPWM) control are calculated respectively, and then the difference between the two calculation results are attained. To determine conditions to be satisfied for the calculation of DC-side voltage of APF under SVPWM control, mathematical formulae describing the mechanism of action of DC-side voltages of single-phase and three-phase APFs are derived respectively, and finally the calculation formula for DC-side voltages of APF is obtained. Through a lot of simulation, the statistical optimal variation range of DC-side voltages of APF that basically copes with the result of theoretical calculation is achieved, thus the reasonableness of theoretical derivation is verified. Source

Meng N.,China EPRI Science and Technology Co.
2011 International Conference on Electrical and Control Engineering, ICECE 2011 - Proceedings | Year: 2011

This paper took lithium battery as the energy storage system of PV grid-connected system, which introduced two forms of energy storage system access to PV, and analyzed the power and energy management of PV-energy storage system. it has also proposed the solutions. © 2011 IEEE. Source

Zhao B.,China EPRI Science and Technology Co. | Guo J.,China Electric Power Research Institute | Zhou F.,China Electric Power Research Institute
Dianwang Jishu/Power System Technology | Year: 2012

To assess the interaction between controlled devices and power grid, real time digital simulator (RTDS) is utilized to implement the assessment by digital models of controlled devices and power grid, that is, through real-time interaction between I/O interfaces and controller, functions and performances of controller under various operating modes, fault conditions and disturbances are fully tested. For this purpose, an RTDS-based scheme of hardware-in-the-loop test for controller performance of STATCOM is proposed, by which such functions as constant reactive power control, constant power factor control, step response and reactive impact response of STATCOM are tested, and the obtained results are compared with results from off-line digital simulation and those of HV prototype tests. Comparisons show that the RTDS-based hardware-in-the-loop test is effective. Source

Li S.,JiangSu JianZhu Institute | Xu X.,China University of Mining and Technology | Zhu N.,China EPRI Science and Technology Co.
Applied Mechanics and Materials | Year: 2013

Multi-robot SLAM is a technology of multi-robot simultaneous localization and mapping cooperatively in unknown environment. We use information filters algorithm to solve multi-robot SLAM problem. Information filers use information matrix to describe the SLAM uncertain information, and multi-robot SLAM information matrix contains all robots poses and all the features observations which observed by all robots. We set up the multi-robot models, motion models and observe models, and set up feature-environment to simulation in computer. We set threshold to divide the features which are observed by robot k on current time, one part of features are used to relocalization as active maps, and the other features are used to update information matrix and information state. The simulation data shows that information filters can keep the accuracy of the robots poses, and keep the motion update and the observation update in the constant range, the algorithm improve the effective of multi-robot SLAM. © (2013) Trans Tech Publications, Switzerland. Source

Zhao B.,China EPRI Science and Technology Co. | Guo J.,China Electric Power Research Institute | Zhou F.,China EPRI Science and Technology Co.
Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering | Year: 2012

Chain structure is widely used in static synchronous compensator (STATCOM), which is composed of several H-bridge modules with identical structure. The stability of DC voltage of each converter determines the stability of the device. This article analyzed the converter chain power equation, sets forth the basic mathematical principles to achieve DC voltage balance control among the converter chains, and put forward an averaging DC voltage control strategy based on negative sequence current. The scheme also took system unbalanced voltage into consideration. Simulation results and industrial prototype tests show the high steady-state control accuracy and excellent transient and dynamic performance of the proposed control strategy, thus proves it to be an effective solution to the chain converter DC voltage control problems. © 2012 Chin. Soc. for Elec. Eng. Source

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