Papers by Author: Bo Yang

Abstract: In view of the problems that traditional direct current control calculation is complex, that sensor precision requirements are high. This paper proposes a new control method of unit power factor power converter, which is easy to realize with simple control structure dispense with current sensor. Through the simulation and experimental verification, the control strategy can achieve unity power factor control, and the harmonic content is small and the operation is stable.

Abstract: Electricity market reform has brought new challenges to transmission grid planning, the traditional only considers a future scenarios of transmission grid planning, this method can’t meet the actual needs. In this paper, the uncertainty factors of market environment is analyzed, based on the relaxation factor and the way of wiring ,the transmission grid planning model is established. The security not only takes the N-1 breaking cases into account, but also includes the same tower Multiple-loop breaking at the same time. The model is solved using the methods based on Monte Carlo simulation and hierarchical genetic algorithm, ultimately the resulting meets reliability requirements and minimum total cost of transmission planning programmes under the future uncertainty environment. To build the simulation model, simulating the different methods of wiring way impacts on the investment and risk of the grid planning.

Abstract: NURBS surface representation, combined with Differential Evolution (DE), enables us to perform automated non-imaging reflector design. The overall result is a simple automated nonimaging reflector design technique and only a little data such as desired illuminance distribution and searching limits are needed. Merit functions specific to non-imaging reflector design are presented. Using different merit functions, the generated illuminance distribution can be uniform as well as concentrated. DE is performed to obtain the reflector that generates the desired illuminance distribution. The photometric distributions are calculated through Monte-Carlo ray tracing and the illuminance value is used to calculate the merit function value. The validity of the proposed approach is demonstrated by optimization examples. Almost the same uniform illuminance distribution can be obtained using the algorithm proposed in this paper as that obtained by edge-raymethod. A concentrated illuminance distribution can also be generated using the algorithm proposed.