Xiao Hui Zeng

Auto-Tuning of Optimal PI Controller Satisfying Sensitivity Value Constrains

For a first-order lag process with dead-time models (FOPDT) under step load disturbances, optimal parameters of proportional and integral (PI) controller are obtained through numerical optimization based on minimizing the integrated time and absolute error (ITAE), or maximizing the integral gain. The optimizations are under constrains of sensitivity functions. Then, the tuning formulas for PI controllers are adjusted according to parameters from numerical fittings of optimized values within a large scope of the ratio of the inertia time to the dead-time of processes. Finally, the process information is acquired from closed-loop tests of a two-channel relay and the process is approximately modeled with a FOPDT model in order to achieve parameter auto-tuning of controllers. The approach proposed is proved to be effective according to simulation results.

The Research of Embedded Techniques in Control Systems of Service Robots

A control system for service robots based on a 32-bit ARM processor with kernel S3C2410 is proposed. The entire structure of the control system of embedded service robots is designed in the paper. And designs of each circuit and software of the system are demonstrated respectively in detail. The control system proposed has advantages of modularized structure, small size, low power dissipation, hard real-time and high reliability, etc.

Generalized Projective Synchronization of Diverse Structures Hyperchaotic Systems with Unknown Parameters

In this paper, the generalized projective synchronization for a general class of hyperchaotic systems is investigated. A systematic, powerful and concrete scheme is developed to investigate the generalized projective synchronization between the drive system and response system based on the feedback control approach. The hyperchaotic Chen system and hyperchaotic Lorenz system are chosen to illustrate the proposed scheme. Numerical simulations are provided to show the effectiveness of the proposed schemes.

Circuit Designs for an Automation Intelligent Electrical Distribution Terminal Unit Based on DSP

An automation intelligent electrical distribution terminal unit is designed in the paper, making full use of the super calculation ability of digital signal processors. Whole hardware design and circuit designs, such as power conversion module, relay control module communication and data storage module etc, are discussed respectively in the paper. Researches on the reliability of the intelligent terminal unit are carried on finally. Results show that the unit can operate safely, stably and reliably.

The Research on Suppression Strategies for Electromagnetic Torque Ripples of Brushless DC Motors

Despite of its remarkable active performances, brushless DC motors, which are widely used in mechanical engineering, have an obvious disadvantage in its high electromagnetic torque ripples. In the paper, a ripple suppression method based on predictive controls of stator currents is proposed according to analysis of causes electromagnetic torque ripples generate in commutation periods of brushless DC motors. First of all, a relative accurate prediction is acquired through DC motor on-line parameter corrections based on generalized predictive control algorithms. Then rolling optimizations make tracking errors and control qualities optimized for best control effects. And finally, minimum electromagnetic torque ripples are achieved. The simulation results show that torque ripples can be suppressed effectively with improved reliabilities by using the method proposed.

The Research on Automatic Liquor Blending Systems Based on Wavelet Neural Networks

The blending of liquors is a key process in the production of liquors. According to time-frequency localization characteristics of the wavelet transform and advantages of the neural network such as ability to develop, fault-tolerance, self-adaptability, self-learning, and robustness, a mathematic model based on wavelet neural networks is proposed in liquor blending processes with the help of computer-aided design technologies, which makes liquor blending technologies more scientific.

Research on Mechanical Industry through Control Systems of Intelligent Robots Based on ARM

Mechanical industry has made a great advance in automation with increasing developments in performances of processing devices. A control system of intelligent robot is designed in the paper, which based on microprocessor S3C2410 with the kernel ARM 920T and the real-time embedded μC/OS-II operating system. The design proposed extends functions of intelligent robots and improve its ability to adapt environments. Otherwise, it will do great help in automations of mechanical systems.

The Software Design for an Automation Intelligent Distribution Terminal Unit in Electric Power Systems Based on C and Assembly Language

Electric power distribution systems play an important role in electric power systems, in which automation intelligent distribution terminal units are critical for the performance of power distribution systems. The software of an automation intelligent electric power distribution terminal unit based on digital signal processor is designed in the paper, a way of admixture programming with C language and assembly language. In this manner, real-time requirement on the electric power distribution system will be satisfied, the reliability and stability of the software are ensured as while. It has a broad application prospects in electric power systems.

A Fault Phase Selection Method Based on Arc Voltages for High-Voltage Line Protections in Electric Power Systems

A fault phase selection method is proposed based on arc voltage after analysis of inadequate of fault phase selector existed in the paper. A precise fault phase selection can be achieved by using arc voltages in conjunction with phase current differences and sequence components of currents. The method proposed can solve false tripping problems in transmission line protections when single phase to ground faults occur with great reliabilities. Simulation results show that the method can identify faulted phase or phases correctly and effectively.

The Research on Directional Elements of High-Voltage Line Protections Based on Zero-Sequence Reactance of Fault Components

Zero-sequence directional elements under a small voltage are studied and a new directional element based on zero-sequence reactance of fault components is presented. From analysis and simulations we have that when a forward fault or a reverse fault occurs, the zero-sequence reactance of a fault component will less or larger than the line zero-sequence reactance respectively. Therefore, the direction of a fault can be distinguished. The simulation results of EMTP show that the directional element based on zero-sequence reactance of fault components can identify forward and reverse faults accurately and it can satisfy requirements of relay protections for high-voltage lines.