| Experiment&teaching is an important part of personnel training and teaching work in college,and is a significant circle of cultivating students'research methods,ability in engineering practice and innovative consciousness,major of instrumentation and meter has mainly such teaching experiments as demonstration,verification,synthesis and design. for now ,teaching experiments are mostly adopted,especially verification experiments.It's the orientation and emphasis for experiment&teaching reform in college to strengthen design and synthesis experiment&teaching projects.In recent years ,during assessment to bachelors'teaching level.,the time ratio between design and synthesis experiment&teaching period is explicitly specified.Virtual Instrument laboratory in our school has applied virtual instrument-tech to experiment&teaching triumphantly ,as well as developed a virtual experiment& teaching system(abbreviated into"VIETS") combining signal generator,data acquisition and analysis&process kits,which has been applied in experiment and teaching to solve the problem in the faculty of science and technology that experiment&teaching is difficult and present test system is expensive.The present hardware of VIETS is controller,DDS signal generator,digital oscilloscope and a high cost-effective private bus ,at the premise of two stated instruments,it's not enough for experiment&teaching.power is a necessary part in it .for experiment with power ,it's an urgent problem to provide DC power with diverse voltage value.on purpose of solving problem of present VIETS lack of flexible output DC voltage,a programmable power is designed ,with characteristics of voltage adjustable both in positive and negative voltage channels. Programmable power can be separated into two parts,hardware and software. in hardware ,module thought is taken to modularize the power according to certain specifications and integrate the power into a 3U size cabinet. Modular instruments are coordinated to work by system controller. System controller communicates with computer through USB2.0 interface.software platform adopts graphic virtual instrument software LabVIEW, which uses CLF node to interface with instrument driver. The instrument driver packages the I/O operation into function by DLL and it calls USB driver to achieve data in & out.The thesis concisely introduces the development background, present status, trend of development of virtual instrument. Through researching the existing VIETS deeply, it establishes the total structure, general planning and specifies a protocol between programmable power and personal bus, it introduces the design of programmable power in detail. Finally it demonstrates that the system with programmable power is flexible through several experiments. |
PDF Full Text Request