钻机顶部驱动控制方法

顶驱是钻机旋转系统的驱动者,其控制方法多样化,寻求切合实际工况的策略,来提升旋转性能。针对钻具在井下是典型的弹性负载,深井作业时其上储藏了不可忽视的弹性反转矩能,引起的扰动严重。提出选择性的投入前馈补偿控制,减弱或消除负载扰动影响,改善驱动系统性能;对于制动控制提出改进办法,来减少不必要的磨损,使得制动过程更加人性化;对弹性反转矩能进行软释放,分析了释放过程的状态及有关计算方法。

A software cost model with maintenance and risk costs for safety-critical systems

According to the consequences of software failures, software faults remaining in safety-critical systems can be classified into two sets： common faults and fatal faults. Common faults cause slight loss when they are activated. A fatal fault can lead to significant loss, and even damage the safety-crltical system entirely when it is activated. A software reliability growth model for safety-critical systems is developed based on G - 0 model. And a software cost model is proposed too. The cost model considers maintenance and risk costs due to software failures. The optimal release policies are discussed to minimize the total software cost. A numerical exampie is provided to illustrate how to use the results we obtained.

神东煤炭集团成功研制3.2km单点软驱动可伸缩带式输送机

近日,神东煤炭集团研制生产的3.2 km矿用长距离单点软驱动可伸缩带式输送机通过内蒙古自治区科技厅组织的科学技术成果鉴定。该项目在运量不变、单点驱动的情况下,整机运输距离从1 km提高到3 km,具有多项技术创新,自主开发了全自动绞车张紧系统,实现了张紧力自动控制、断电后张力保护和ABS张力软释放功能,填补了国内空白。整机H架轻型化及起高装置设计提高了带面延伸安装速度,降低了工人劳动强度。输送距离长、单点变频驱动、节能效果达22%、故障率低、安装便捷,采用鼓形滚筒解决了胶带跑偏。