文献翻译-基于制动试验台的虚拟仪器与变频技术.docVIP

附录 VIRTUAL INSTRUMENT AND FREQUENCY CONVERSION TECHNOLOGY-BASED BRAKE TEST SYSTEM Brake is widely useful and very important safety assuring equipment. The aim of Brake test system， which is based on visual instrument and frequency changing technology， is to integrative measure and analyze the performance and quality of the brake.This paper mainly introduces the principle， composing，function and features of the brake test system. And from the point of view of the principle of Visual Instrument （VI） technology， a test system， based on the VI and frequency changing technologies and consist of frequency changing drive and control sub-system and measuring sub-one， is constructed. With the test system the performances and braking course could be auto controlled and measured to the brakes which includes disc and drum ones. And the measuring and control software is programmed with the LabVIEW published by American NI Corporation， USA.Then data real time acquisition， processing， displaying and recording will be realized. The test system also has the functions of voltage adjusting， rotating speed control， load regulating， JC value setting， temperature measuring， and braking route and time memorizing and analyzing. It will be very important for meaning and exciting boosting effect to advance quality and capabilities of the brakes and the security of equipments and system which have adopt the brakes. 1 Operating principles According to the principle of work and power， the change of kinetic energy in the moving of objects equals to the full power of the force act on the object in that process.The energy obtained by brake to be tested： Therefore， it is feasible to use combined inertial flywheels to simulate rotating inertia of crane hoist and its transmission components to test the performance and quality of the brake. According to the moment of momentum theorem： Tb·t =Ji·ω （1） When Tb is fixed， tb can be controlled through combinations between Ji and ω differently. Brake drum or