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Cheng Z.,Hefei University of Technology | Li M.,Anhui Electrical Engineering Professional Technique College
Proceedings of IEEE International Conference on Grey Systems and Intelligent Services, GSIS | Year: 2013

Med-long term load forecasting is the basis of power system planning. According to the characteristics and changing rules of the different types of electricity load and different demand side management strategies on them, electricity load structure forecasting for the research on power development and planning is very necessary. Based on the grey theory, this paper proposes a med-long term load structure forecasting model in which the system state equations and grey dynamic model group about various types of electricity load are established, in terms of the system dominant factors and associated factors determined by the grey correlative degree analysis method, and are solved to realize the med-long term structure forecasting of power consumption by means of the GM (1, N, x (0)) model derived from GM (1, N) model. The power consumption of actual grid is predicted in medium and long term in a case study utilizing the proposed model. The prediction results are analyzed and compared with the observed values of power consumption, which verifies the validity and practicality of the established med-long term load forecasting model. © 2013 IEEE.


Li R.-J.,Hefei University of Technology | Li R.-J.,Anhui Electrical Engineering Professional Technique College | Fan K.-C.,Hefei University of Technology | Fan K.-C.,National Taipei University | And 4 more authors.
Precision Engineering | Year: 2015

This paper presents a long-stroke contact scanning probe with high precision and low stiffness for micro/nano coordinate measuring machines (micro/nano CMMs). The displacements of the probe tip in 3D are detected by two plane mirrors supported by an elastic mechanism, which is comprised of a tungsten stylus, a floating plate and two orthogonal Z-shaped leaf springs fixed to the outer case. A Michelson interferometer is used to detect the vertical displacement of the mirror mounted on the center of the floating plate. An autocollimator based two dimensional angle sensor is used to detect the tilt of the other plane mirror located at the end of the arm of the floating plate. The stiffness and the dynamic properties are investigated by simulation. The optimal structural parameters of the probe are obtained based on the force-motion model and the constrained conditions of stiffness, measurement range and horizontal size. The results of the performance tests show that the probe has a contact force gradient within 0.5. mN/μm, a measuring range of (±20. μm), (±20. μm), and 20. μm, respectively, in X, Y and Z directions, and a measurement standard deviation of 30. nm. The feasibility of the probe has preliminarily been verified by testing the curved surface of a convex lens. © 2015 Elsevier Inc.


Li R.-J.,Hefei University of Technology | Li R.-J.,Anhui Electrical Engineering Professional Technique College | Fan K.-C.,Hefei University of Technology | Fan K.-C.,National Taiwan University | And 3 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2013

The measurement of miniature components with a micro- or nano-coordinate measuring machine requires a high precision contact scanning probe. The elastic mechanism of low stiffness is a major component of the contact scanning probe. A new elastic mechanism is analyzed by the theory of elasticity and finite element analysis in this paper. It is to realize the probe's mechanical behavior and stiffness when designing an elastic mechanism for a contact scanning probe. The contact scanning probe is composed of a tungsten stylus with a ruby ball tip, a mechanism of floating plate suspended by four V-shaped leaf springs, and a 3D optical sensor. The leaf spring experiences elastic deformation when a contact force is applied. Uniform stiffness model is analyzed. Simulation and experimental results verify the correctness of the analysis. © 2013 SPIE.


Li R.-J.,Hefei University of Technology | Li R.-J.,Anhui Electrical Engineering Professional Technique College | Fan K.-C.,Hefei University of Technology | Fan K.-C.,National Taiwan University | And 4 more authors.
Precision Engineering | Year: 2016

This paper presents a long-stroke contact scanning probe with high precision and low stiffness for micro/nano coordinate measuring machines (micro/nano CMMs). The displacements of the probe tip in 3D are detected by two plane mirrors supported by an elastic mechanism, which is comprised of a tungsten stylus, a floating plate and two orthogonal Z-shaped leaf springs fixed to the outer case. A Michelson interferometer is used to detect the vertical displacement of the mirror mounted on the center of the floating plate. An autocollimator based two dimensional angle sensor is used to detect the tilt of the other plane mirror located at the end of the arm of the floating plate. The stiffness and the dynamic properties are investigated by simulation. The optimal structural parameters of the probe are obtained based on the force-motion model and the constrained conditions of stiffness, measurement range and horizontal size. The results of the performance tests show that the probe has a contact force gradient within 0.5 mN/μm, a measuring range of (±20 μm), (±20 μm), and 20 μm, respectively, in X, Y and Z directions, and a measurement standard deviation of 30 nm. The feasibility of the probe has preliminarily been verified by testing the curved surface of a convex lens. © 2015 Elsevier Inc. All rights reserved.


Li R.-J.,Hefei University of Technology | Li R.-J.,Anhui Electrical Engineering Professional Technique College | Fan K.-C.,Hefei University of Technology | Fan K.-C.,National Taiwan University | And 4 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2011

A new high precision analogue contact probe with long measurement range that is able to measure miniature components on a micro/nano-coordinate measuring machine (CMM) is proposed. This analogue probe is composed of a fiber stylus with a ball tip, a mechanism with a wire-suspended floating plate, a two-dimensional angle sensor and a miniature Michelson linear interferometer. The stylus is attached to the floating plate. The wires experience elastic deformation when a contact force is applied and then the mirrors mounted on the plate will be displaced, which displacements can be detected by two corresponding sensors. Each component of the probe is designed, fabricated and assembled in this research. Base on the design requirements and stiffness analysis of the probe, several constrained conditions are established, and optimal structure parameters of the probe are worked out. Simulation and experimental results show that the probe can achieve uniform stiffness, ±20μm measurement range and 1nm resolution in X, Y and Z directions. The contact force is less than 50μN when the ball tip is displaced by 20μm. It can be used as a contact and scanning probe on a Micro/Nano-CMM. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

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