Advanced Materials Research Vols. 760-762

Abstract: In this paper, a modified Michelson interferometer is designed to measure Terahertz spectrum. Compared with normal Michelson interferometer, hollow retroreflectors are used instead of flat mirrors as reflective mirrors. The theory analysis and some measurement are given.

Abstract: Earthquake prediction is one of the most difficult problems in modern natural science. Undoubtedly, various seismic parameters included in broadband radiated energy catalogue of NEIC is very important data source of investigate correlation between differernt earthquake within specific time space scope and earthquake prediction. In the paper, we a linear fitting mode of seismic magnitude based on method of least squares and seismic energy is established, using which we can fill the absent energy filed in the broadband radiated energy catalogue.

Abstract: Power electronic transformation system is applied widely in industrial control and the application environment is complex. Big, small and medium-sized system power consumption improves continuously, so it is urgent to reduce the system energy consumption problems. This paper proposes a way to reduce the energy consumption of power electronic transformation system based on genetic algorithm. Work frequency regulation and working voltage measurement technology are used in industrial control system and the voltage and frequency produced by system power consumption are calculated. Genetic algorithm is used to calculate the optimal solution. And then achieve the purpose of reducing energy consumption. Experimental results show that this control algorithm can effectively reduce the power consumption of power electronic transformation system in industrial control and has a good effect.

Abstract: Human body temperature, as a manifestation of life activity, is an important physiological parameter of the new supersedes the old. The body temperature not only has physiological significance, but also has important clinical significance, which can be considered as an important index for clinical diagnosis. Based on the NTC temperature sensor as the core, through the whole system framework construction and the software control system design, a quick and accurate intelligent digital electronic thermometer was prepared. Under software control, intelligent temperature measurement is realized. The thermometer not only can accurately register the temperature, also has many functions such as broadcast and logic judgment on temperature, in which, the display module will judge and display the measurement results.

Abstract: This paper designs a current source which is used for simulating the three dimensional magnetic field. Gives the circuit schematic, Analyzes the design principle of the circuit and puts forward the calibration method of software which is suitable for the operation in microprocessor and improves the output accuracy of the constant current source. Actual test shows that the output of the constant current source is 0.1mA-500mA and the precision error is less than 0.03% of full scale. It has been used in the degaussing device testing and maintenance. The performance is stable and reliable achieves good results.

Abstract: With the rapid development of radar system, it has put forward higher requirements in the ability of real-time signal processing, the capability of data processing and the versatility of signal processing platforms. The signal processing unit based on PowerPC processor MPC8640D can complete the calculation of complex data using the superior performance of the processor. The combination of embedded operating system VxWorks can meet the real-time requirement of the radar signal processing perfectly. Universal IO interface definition of PowerPC processors make the designed signal processing unit own excellent versatility. The use of muti-beam digital synthesis technique and the vector library in software development improves the signal processing further more.

Abstract: The electro-magnetic torque and current are analyzed for a static eccentric PMSG. The characteristics of air-gap magnetic field, EMF, current and electro-magnetic torque of the direct driven PMSG for wind power generation are investigated with Maxwell software various eccentric conditions. The related electrical magnetic torque and current variation are achieved, especially the harmonics for current and torque.

Abstract: The existing parallel type pressurized water supply pipeline of high-rise buildings has been improved to build energy-saving high-rise building water supply systems. Series-parallel combined constant pressure water supply pipeline is designed. Antipollution high water tank is reasonably installed above the middle area of the building to supply water for the middle area high water tank and supply pressurized water by water pumps for high-rise district. And PLC control system is designed to control the work efficiency of the water pumps according to the sensor feedback information. Verified by calculation and simulation, series-parallel combined constant pressure water supply pipeline is better than parallel water supply pipes in saving the energy which is about the middle-Hybrid phase consumption of the latter. PLC control is simulated and the results show that PLC can effectively control the water supply system to ensure stable water pressure so as to save energy.

Abstract: As a particular user of the power system, electric railway has the characteristics of non-linear, asymmetric and volatility. The power quality indicators of electrified railway were analyzed and summarized in this paper. The harmonic content rate reference value of various types of locomotives was given as well as the calculate method using in the power quality assessment, which are suitable for engineering applications. At last, this paper gives several effective measures on improving the power quality.

Abstract: A supercritical coal-fired power generating unit is a typical multivariable system with large inertia and non-linear, slow time-variant, time-delay characteristics, which often makes the coordinated control quality deteriorate under wide-range load-changing conditions, and can't well satisfy the unit load and main steam pressure control requirements. Thus, it is of vital significance to study the supercritical boiler units operation characteristic by means of modeling method, and to improve the control quality with model-based advanced control strategies. In this paper, artificial neural network (ANN) method was used to build a nonlinear mathematical model of the load and main steam pressure characteristics for a 600MW supercritical boiler unit. Operation data over wide-range load-changing conditions were used for model training. Simulation tests showed that the model can fit the complex non-linear, dynamic characteristics between the units load, main steam pressure and fuel, feedwater flow and turbine governing valve opening with high precision and strong generalization ability. The model can be used as a prediction model to construct an intelligent controller for supercritical boiler unit coordinated control to meet the engineering application demand.