| Vacuum interrupters have been widely used in electric power system and other industrial fields. The vacuum level in vacuum interrupters is one of the most important conditions to guarantee their performance. Realization of the online monitoring of pressure in vacuum interrupters is one of the main concerns of their intelligentizing. However, several techniques already presented recently still cannot meet requirements in practice. In vacuum measurement technology, although pulsed operation of inverted-magnetron gauge (IMG) theoretically has many advantages, its research and application have been checked because of the difficulty of extending its lowest measurable pressure, and concerned research literature has not appeared as yet.The dissertation investigated the theories about crossed-field discharge in high vacuum, which are the physical basis of IMG Then according to the principles of Monte Carlo computer simulation of gas discharge, computational method for simulation of high-vacuum crossed-field discharge in IMG was designed, and the corresponding program was implemented to investigate some basic process of gas discharge in crossed-electric-magnetic field.Based upon some of the concerned results of the above research, a type of diode IMG and a kind of adjustable, pulsed, high-voltage generating circuit were designed. Some experiments were performed to investigate the different characteristics of the pulsed operation mode of this diode IMG and its DC discharge mode; its constant-voltage discharge and constant-current discharge mode of measurement in pulsed operation, the Volt-Ampere characteristics of discharge under different pressures, the effect of the length of discharge space on the discharge current, and that of magnetic field on the discharge current were also studied. A kind of measuring method was devised according to the alteration of discharge current during the action of high-voltage pulse, which can greatly reduce the influence on the vacuum measurement of the pump effect of the discharge. An operation method of leading-pulse type was presented in experiments. This method can greatly shorten the starting time of the IMG at low pressures and thus can effectively extend its lowest measurable pressure. Experimental results showed that the pulsed operation mode of this type of IMG can have a measurable pressure range of 3 × 10-4 Pa to 0.5 Pa, which well meets the requirement of the pressure measurement of vacuum interrupters. A new type of vacuum chamber with intelligent vacuum sensor was designed according to the above experimental and research results. The discharge unit of the vacuum sensor is a simple diode IMG which runs in pulsed operation mode. The pulsed high voltage needed by the IMG is obtained by stepping up that of batteries (LiSOCl2) through DC/DC conversion. The discharge and pressure measurement are controlled by a MCU; measured results are transferred through wireless or infrared interface to other receiving device. This vacuum sensor, being a stand-alone working unit, not only has no influence to the normal operation of vacuum interrupters, but also is independent of the working parameter of vacuum chamber. Therefore, it can be applied to vacuum chambers of all-level voltage. Low-power consumption is characteristic of the vacuum sensor circuit and, with once replacement of battery (Li/SOCl2) the sensor can have an operation life of nearly 10 years. By adopting this new type of vacuum chamber, the online monitoring of pressure in vacuum interrupters can become practical, which is very significant for their being intelligent.
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