Evaluation of power quality in a missile test range using a PC based power disturbance analyser

In a missile test range, where the flight testing of various types of guided airborne vehicles are performed, a high quality power supply is most essential for the proper and reliable operation of the sophisticated instruments and computers. This paper presents the special factors involved in the evaluation of power quality in a missile launch center. A PC-based power disturbance analyser is discussed which is specially designed to meet the stringent requirements of power quality in such an environment. The paper discusses, in detail, the configuration and performance of the disturbance analyser developed around an Intel Pentium processor and intelligent data acquisition card. The line voltage and current are brought down to /spl plusmn/10 V by suitable transducers. The software modules in the PC control the configuration of the card as well as data processing, logging and display. The different software modules developed are: (1) out of limits only module to check for slow voltage changes; (2) harmonic analysis module; (3) impulse monitoring module; and (4) real-time waveform display and recording module with playback facility. The system is tested with simulated signals as well as in the field and the results are analysed. A number of these systems will be installed at various sites for local power system monitoring.