个人网页的制作论文.doc

摘 要
煤矿井下的生产广泛使用了交流异步电动机,但是井下工作环境恶劣,高温、高湿致使电动机的烧损情况相当严重,不仅造成直接经济损失,而且影响煤炭生产效率,给井下工作人员的生命安全造成隐患,因此改变这一状况十分迫切,加强电动机保护是改变这一状况的有力技术措施,逐步引起人们的重视。
经过对采煤机生产厂家的实际调研,针对目前异步电动机漏电故障诊断及保护系统的不足和存在的问题,通过深入研究异步电动机漏电故障的产生原因、故障机理,掌握了发生漏电故障情况下所表现出来的异常特征,在附加直流电源式的漏电保护原理的基础上,提出了霍尔采样电路,实现以硬件保护为主、软件检测为辅、实时监控的漏电保护装置。其中针对采煤机牵引电动机,分析了其运行过程中干扰产生的原因、机理,掌握了干扰所表现出来的异常特征,设计开发了减法装置,可抵消变频调速装置对电动机产生的干扰信号,进一步提高了电动机漏电保护的可靠性和保护精度。本装置设计简单、易于实现、误动率低、准确率高,可有效提高采煤机电动机检漏装置动作的可靠性。
本论文根据所确定的装置功能,对异步电动机故障检测装置的硬件和软件部分进行了选型、设计与实现,并通过厂家提供的实验台,对装置的功能进行了实验,验证了本设计保护功能较完善、方法新颖、接线简单,具有较强的实用价值。关键字:采煤机,异步电动机,漏电保护
ABSTRACT
The AC asynchronous motors are extensive used in coal mine production, because of the execrable working conditions and so on, motors are always burnt. Not only caused direct economic losses, but also affect coal production and bring hidden trouble to the life safety of people working in the coal mine. So to change this situation is very urgent, to strengthen the motor protection is a strong technical measures to change this situation.
After researching the coal winning machine manufacturer and the current motor leakage fault diagnosis and protection system's deficiencies and problems, through in-depth research the causes of the leakage faults and fault mechanism of mon asynchronous motor, I master the unusual characteristics of the motor when leakage faults happening, Hall sampling circuit was put forward on the basis of the type of additional dc power leakage protection principle, realizing the mainly in hardware, software test subsidiary, real-time monitoring of leakage protection devices. Among them for coal winning machine traction motor, analyzing the cause and mechanism of interference, I master the abnormal characteristics that the jamming shows and design and develop the subtraction devices that can be offset by frequency control of motor speed device to motor of the interference signals, further improve the reliability of the leakage protection motor and protect precision . This device i