NC machine tools are generally thought to be with a high degree of automation, high precision, high reliability and high efficiency characteristics. But because of the inherent flaws of the machine mechanical structure, such as screw wear, assembly errors or repeated positioning error, the machining accuracy may reduce. Therefore, this paper describes a self-compensating system design FPGA-based NC machine tools. Using Programmable devices(FPGA) and Hardware description language(VHDL) to achieve self-compensation system controller development, Position measurement from absolute encoder in real-timing, Comprehensive building of NC machine tools since compensation control system.

A three-phase 12/8 pole switched reluctance motor drive system is introduced based on single chip microcontroller STC12LE5410AD and CPLD EPM240T100C5N. The design details of the controller are described in this application .To solve the nonlinear problem of switched reluctance motor, PI control algorithms are used to achieve the motor current control loop and speed control loop. The experimental results show that the hardware and software design of switched reluctance motor drive system are reasonable, and the proposed dual closed-loop control method is correct and feasible.

In this paper, hardware composition and software design of auto-scaling system for electrical tuned attenuator based on GPIB is proposed. The proposed system is mainly composed of personal computer, USB-GPIB interface card, phasor network analyzer, data acquisition card and electrical tuned attenuator. System software is developed in graphical programming language LabVIEW. It can realize the insertion loss measurement and scaling of electrical tuned attenuator in the frequency range from 0 to 20GHz.The system can greatly reduce the time of scaling. Comparing with the conventional scaling system, this system is advantageous in reducing the time for taking measurement and in simplifying the method of scaling and testing.