Xiaobo Huang

A resource allocation approach via the genetic algorithms in electric power communication networks

In this paper, we investigate the resource allocation problems in electric power communication networks. Considering the fundamental issues of resource allocation, we propose a new resource allocation model. In the proposed model, we first involve the social distance parameter to evaluate the relationship between the difference users in the same service requirement set. Then we propose an optimization model to solve the bandwidth problem for each user in a link. The optimization model takes account of a utility function with the social distance function. As an objective function, the utility function can describe the link efficiency perfectly. We finally solve this optimization model by the genetic algorithm. Then we will assess the performance of our method. According to the simulation results, our model can obtain allocate a bandwidth for each user with a high utility.

Photovoltaic Grid Connected Inverter Crossing Control Method Based on Grid Voltage Feed forward Compensation

According to the requirements of relevant national standards, large photovoltaic grid connected inverters need to have zero voltage ride through (ZVRT) capability to prevent low voltage automatic disconnection, thus affecting the normal and stable operation of power system. On the basis of analyzing the ZVRT standard of PV grid connected inverter, the key technologies of inverter realizing ZVRT are discussed in detail, including grid voltage positive and negative sequence separation and phase locking, active and reactive current control of inverter, system control under unbalanced grid voltage and so on. On this basis, it is further proposed that the grid voltage feed forward component phase lead compensation link should be introduced into the system current loop, so as to improve the transient overshoot of grid connected fault. Finally, the correctness and effectiveness of the ZVRT control strategy of the PV grid connected inverter is verified by the experimental results of RTDS and a 500 kW prototype.

A Modeling Algorithm to Network Flows in OTN Based on E1 Business

Recently, Optical Transport Networks (OTN) have been extensively deployed and applied in communication networks. Compared with traditional transport networks, OTN can provide much larger traffic transport ability. However, the properties and characteristics of network flows in OTN are not deeply studied and this is still a larger gap between theory analysis and practical applications. This paper studies the modeling problem of network flows in OTN. We propose a Walsh transform-based modeling method to describe end-to-end traffic amount of network flows in OTN. Firstly, the end-to-end traffic is denoted as a independent identically distributed random time-varying series. Then the Walsh transform theory is used to characterize the end-to-end traffic of network flows. By calculating the corresponding parameters, the proposed model is build correctly. Simulation results show that our approach is feasible and effective.

Multi-Channel Interleaved paralleled phases Shifted Factor Correctors with Passive Control Strategy

High power single-phase PFC such as multi-level interleaved APFC or single-level APFC with multiple power devices in parallel is required for high-power household electrical appliances, communication power and other electric-equipment which are supplied by single-phase AC power source. This paper theorizes an APFC(MxN APFC)with M-channel interleaved N- paralleled switches which is driven by phase-shifted control method. Then the paper analyzes its circuit structure and working principle, including variable ratio of voltage, ripple circuit, driving method and the control scheme. This selection, while maintaining the work frequency of the boost inductor or keeping the same switching frequency of devices, doubles the work frequency of the boost inductor, also, simplifies the inductor design. This paper takes 2x2 APFC as an example of the MATLAB/SIMULINK simulation analysis. The experimental research obtains satisfactory results and verifies that the overall solution is workable.