Design on Vibration Monitoring and Fault Diagnosis System of Large Water Pump Motor

Large water pump motor,whose operation decides the reliability of the whole production line,plays a very important role.Therefore,its online condition monitoring can help companies better know its operation,process fault analysis and protection.The essay mainly studies and designs large water pump motor′s real time vibration monitoring and fault diagnosis system.The essay completes the systems project design,the establishment of the system and performance test.Eddy-currentsensor,XM-120 vibration module,XM-320 axial translation module,XM-362 temperature module,XM-360 process amount module and XM-500 gateway module are used to measure the axial vibration and displacement of main motors.Laboratory tests prove that the system can meet the requirements of motor vibration monitoring.

Analysis of force and leakage in water hydraulic motor's piston pairs

The positive pressure between pistonwall and piston hole of inner curve water hydraulic motor’s piston pairs is analyzed.The flow field of the piston pairs is numerically calculated and analyzed by the use of computational fluid dynamics method.The pressure and velocity distribution of flow field at different clearance is analyzed in the paper.The results show that when the clearance is 4-8 μm,with the increase of clearance,the negative pressure and the velocity of piston chamber decrease significantly,the velocity and leakage flow of the clearance increase.However,when the clearance is 10 μm,the negative pressure and the velocity of plunger chamber increase suddenly.By comprehensive analysis,the cylinder annular clearance should be controlled to be near 8 μm.

The Design of a Mobile Phone-Based Remote-Control Application to Submersible Motor for Effective Water Supply

In the last few decades, several monitoring systems integrated with water level detection have been the major research focus. Production boost and its sustainability depend mainly on sustainable water supply, measuring water level, and avoiding waste of water is an essential task for all stakeholders. Therefore, the aim of this paper is to design and implement a mobile phone-based remote control. This will be applied to control the operation of a submersible motor in a water tank. The water level in the tank is detected and the device remotely turns the motor pump on/off. The design process is accomplished by developing an android application that works on GSM technology to manage the filling of water tank. An AT89C51 microcontroller is used for the desired programming. At the transmitting end, sensor is used for level detection and GSM module is used to send the information to user. According to this information, user controls the on/off operation of the pump. A SIM card is required for its operation and it works on attention (AT) commands. After the design and implementation of the device, the test results showed that all features of the device worked properly, and the device functions exactly as expected. More significantly, the paper has shown that ultrasonic sensors can be used to determine the level of water in a water tank and a GSM module can be used to control a submersible pump. The design and implementation of this device can help to reduce waste of time and power. Ultimately, it avoids water wastage thereby ensuring availability, conservation, and sustainability of water supply.

Dynamic Modelling of Submersible Pump Based Solar Water-Pumping System with Three-Phase Induction Motor Using MATLAB

The main purpose of this paper is to design and model a water-pumping system using a submersible multi-stage centrifugal pump driven by a three-phase induction motor. The system is intended for pumping water to the surface from a deep well using three power supply systems: a general network, a photo-voltaic (PV) system, and a PV system with a battery bank. These systems are used to compare two three-phase induction motors—namely, a motor with a drive and another one without a drive. The systems dynamic models are simulated in MATLAB/Simulink and the results compared with the manufacturer’s data for validation purposes. The simulation results generally show system dynamics and expected performance over a range of operation.

Investigation of Valve Plate in Water Hydraulic Axial Piston Motor

This paper has introduced the developments of water hydraulic axial piston equipments. According to the effects of physicochemical properties of water on water hydraulic components, a novel valve plate for water hydraulic axial motor has been put forward, whose moment exerted by the fluid field between valve plate and bearing plate is balanced entirely. The material screening experiment of valve plate is done on the test rig. Through numerical simulation the effects of some geometry parameters on the performance of water hydraulic motor have been studied. The silencing grooves on the valve plate in water hydraulic motor can reduce the pressure shock and the occurrence of cavitation effectively. It is evident that the appropriate structure should change the wear status between matching pairs and reduces the wear and specific pressure of the matching pairs. The specimen with the new type valve plate is used in a tool system.

考虑同步启动低频电流影响的蓄水电动机组继电保护配置方法

在蓄水电动机组继电保护配置过程中,因电动机组同步启动时参与同步振荡,导致低频电流幅值较大,影响电网运行的安全性。针对这一情况,提出考虑同步启动低频电流影响的蓄水电动机组继电保护配置方法。针对蓄水电动机组不同电压下的线路进行线路保护配置和整定,将保护装置与断路器相连,并制定一套阶段式保护,实现对蓄水电动机组线路的保护,在此基础上,根据电动机组的工作阶段采用两种不同的整定方式,实现对蓄水电动机组的过流保护,考虑同步启动低频电流的变化,改进低功率保护整定,自动调整低功率保护动作值。结果表明:提出的蓄水电动机组继电保护配置方法能够快速消除故障,及时调整机组工作状态。在该配置方法作用下,线路的连锁故障率比较低,进一步保障了蓄水电动机组的安全运行。

海洋平台潜海水电机绝缘失效解决方法探讨

针对目前国产电动海水提升泵电机绝缘失效率高、质量不够稳定的问题,结合实际案例,通过温度场仿真分析等方法,得出潜海水电机绝缘失效的主要原因包括绕组线选型缺陷、内部散热不足、密封性能差和缺少温度监控。针对上诉原因,逐条提出可行的改进方法,提高电动潜海水泵的产品质量。

An Appraisal of Water Availability, Infrastructures for Faecal Disposal and the Potential of Spread of Infectious Diseases in the Traveling Agencies and Motor Parks in the City of Yaounde (Cameroon)

The number of interurban and urban-rural travelers in the city of Yaounde has recently exceeded one hundred thousand per year, yet surprisingly few studies have assessed travelers’ behavior, illness, and risk factors in a sanitary risks setting. Particularly scarce are surveys of data spanning travel, return, and follow-up of the same cohort in traveling agencies and parks. This study examines behavior and illness among travelers moving from Yaounde to other urban and rural areas of Cameroon and beyond. Patterns of behavior connected to a type of travel and illness are characterized in this study so as to identify risks factors and provide background data for pre-travel advice in our traveling agencies. Assessing the susceptibility that imported cases could pose to the national response to infectious diseases depends both on public health, health services and infrastructures. The six agencies assessed: Nvan, Mokolo, Tongolo, Biyem Assi, Mimbowman and Etoudi reveal that the sanitary infrastructures for faecal and urinary disposal are not sufficient and more so, some agencies do not keep enough cleanliness, let alone provide adequate hand washing material as prescribed by national and international concerns to combat the global health challenges. This could be an impediment to travellers going out or inside of the city, and could be a preponderant mechanism for the spread of infectious disease as presented by the infectious diseases isolated and identified in the health districts around the travelling agencies.

离心超重力油水分离器流场特性的数值模拟研究

随着油田开采逐渐进入高含水期,对油水分离器的性能要求也愈发严格,现有油水分离器已很难达到分离要求,油水分离领域亟需新的研究进展。通过数值模拟的方法对一种新型离心超重力油水分离器流场特性进行了研究。从流动参数、结构参数以及物性参数3个方面探究不同参数对分离器分离性能及流场特性的影响规律。研究结果表明:各含水体积分数情况下该分离器分离效果都较好,油出口分离效率随着含水体积分数上升而减小,且含水体积分数较高时水出口的含油量较低;随着入口流量的增大,水出口含油量不断增大,油出口分离效率先减小后基本不变;随着电机转速的增大油出口分离效率先增大后基本不变,电机转速为500 r/min时,油出口分离效率为82%,电机转速为1500 r/min时,油出口分离效率增大至97%;在模拟范围内叶片数量与分离效果呈正相关;油密度和油黏度与分离器分离效果均呈负相关,其值越大分离效果越差。研究结果可为离心超重力油水分离器的实际应用提供理论指导。

充水式潜水电机温度场仿真分析

为了避免充水式潜水电机在运行过程中局部过热导致绝缘失效,造成匝间短路故障的问题,提高电机运行的可靠性,以一台500k W充水式潜水电机为例,搭建了充水式潜水电机包括冷却器、外部水道、吸水罩在内的三维全域温度场仿真模型。模型对定子槽内部分进行了简化的同时考虑了定子槽内冷却水的流通,进一步提高了温度场仿真的精度。最后,对充水式潜水电机内外循环散热过程进行了仿真分析,并通过搭建充水式潜水电机试验平台对温度场仿真结果进行了验证。

高压水泵驱动电机绝缘特性在线监测技术的研究与实现

泵站电机投运前需对其绝缘电阻进行测量以确定其是否满足规程要求。当前绝缘电阻的测量主要采用兆欧表人工手摇检测,检测操作繁琐,费时费力。为了实现电机绕组绝缘特性的快速检测,设计了一种在线监测装置。该装置利用高压模块产生DC 2500 V电压,利用采样模块和档位控制单元实现了被测电阻在1~10000 MΩ时档位的自动切换,利用时间常数法测量出电机对地分布电容值。对比测试表明电机绝缘特性在线监测装置在全量程范围内电阻测量精度可达±5%,同时具备吸收比、极化指数及分布电容等参数的测量功能,满足电机绝缘特性测试要求。

定冷水泵电动机异常振动原因分析及处理

【目的】某电厂#1发电机定冷水泵A和冷水泵B的电动机振幅都超过了规定的标准值,且振动不稳定,振幅有抬升趋势,对设备安全、稳定运行造成了极大的隐患。为消除设备异常振动,使设备安全稳定运行,须对设备进行振动监测和分析。【方法】经振动分析仪监测和分析,认为电动机地脚螺栓松动,电动机台板变形和基础未有效灌浆是导致电动机振幅超标的原因。【结果】对电动机地脚螺栓进行了紧固后,定冷水泵B电动机各个方向振幅均降到了标准范围内。由于机组暂时没有停机计划,无法对电动机基础进行灌浆、更换台板,因此创造性设计了紧固组件。【结论】该紧固组件可有效解决因台板变形和基础未灌浆导致的振动超标问题。

水冷永磁防爆电机十字形肋片的优化设计

为了研究不同水冷结构对水冷永磁电机散热性能的影响,以一台水冷永磁电机为研究对象,优化十字形肋片结构对轴向“Z”字形水路,通过分析加入水道中的十字形肋片的结构参数,确定横肋的高度和数量两个影响参数,采用Workbench对电机进行三维建模,获得不同横肋高度和数量下的电机各部温度分布。结果表明,对比分析电机各部分温升,得到最优冷却结构的横肋数量为3时冷却效果最佳,定子、绕组、转子和永磁体的最高温度分别下降15.32、15.41、11.24和11.24℃。

高水基液压马达功率回收型试验台的研制

高水基液压马达性能试验无法采用常规的液压马达试验装置。根据高水基液压马达功率回收型试验台主要技术性能要求,分析了高水基液压马达功率回收型试验台工作原理,研制了高水基液压马达功率回收型试验台。该试验台加载方式采用AC型交流电力测功机,电力回馈系统采用交流变频调速与配电系统,运行3 a多,效果良好。

铝合金水冷电机外壳的搅拌摩擦焊工艺流程

电机在提供动力的同时会产生大量的热量;一般采用铝合金水冷电机外壳为电机降温来保证其使用寿命。铝合金水冷电机外壳采用焊接的方式来保证其水道的密封性。与传统的熔化焊相比,搅拌摩擦焊方法以及合理的焊接工艺能够有效地减少焊接缺陷、降低热输入、提高产品的一次合格率。搅拌摩擦焊工艺过程可在此类铝合金产品中推广应用,为此类产品在后续新能源领域的发展提供坚实的基础。

南水北调某大型贯流泵站电动机异响原因分析及解决措施

为了解决南水北调某大型贯流泵站电动机运行异响问题,本文对卧式同步电动机构成和工作原理进行了分析,对主电动机进行了抽芯检查并深入分析了主电动机异响问题产生的原因。在此基础上,提出了更换电动机两端轴承、削磨挡风圈、打磨锉平硅钢片磨损部位、截断过长绑扎线和清理冷却器管路等措施,检修维护完成后的电气试验和试运行表明电动机异响消失,所采取的措施取得了理想效果。本文研究结果可为同类型泵站主电动机同类型问题的解决提供一定的参考,从而不断改进与完善主电动机设计、制造与日常运行维护质量,提升泵站主电动机日常养护能力,有助于保障泵站的长期安全可靠运行。

高水基非圆齿轮马达配流盘表面划伤分析与修复

针对高水基非圆齿轮马达配流盘端面出现划伤现象,从非圆行星齿轮机构设计、高水基乳化液污染、高水基非圆齿轮马达零部件加工及装配等方面进行分析,提出了配流盘表面划伤修复方法,并在非圆行星齿轮机构、乳化液清洁度、零部件加工质量、配流盘材料表面硬度及装配质量等方面提出防止配流盘表面划伤的措施。

矿用水冷永磁防爆电机分水台优化设计

为研究不同冷却水道结构对永磁水冷防爆电动机冷却性能的影响,以永磁水冷防爆电动机为例,按照电机设计的步骤,通过对电机的模拟仿真,提出轴向Z字型水道分水台结构,并对永磁水冷防爆电动机水路进行优化。对电机初始模型建立三维模型,通过有限元多物理场计算,得到电机在额定负载下的温度分布情况,并基于传热学和流体力学,对加入轴向Z字型水道分水台的位置比例、数量2个方面展开研究。对电机进行CFD仿真模拟,利用有限元分析,得到不同情况下电机的温度分布图,结合实际情况与经济分析,得到电机分水台数量为2时冷却结构为最优解。

医院恒压供水系统的设计与应用

针对医院院内对供水水压稳定度的要求,基于PID电气控制原理,结合PLC及变频器,设计了医院恒压供水系统。首先,根据医院对于水压的要求选择供水水泵(三相异步电动机)。然后,根据水泵电机功率选择变频器。最后,设计电气主电路、控制系统运用PLC的PID控制功能实现恒压供水。实际测试表明,与传统供水系统相比,设计的恒压供水系统供水水压更稳定且耗能更低,能实现医院对恒压供水供给的要求。

滋水涵木针法联合头穴透刺治疗卒中后上肢运动功能障碍临床研究

目的探讨滋水涵木针法联合头穴透刺治疗卒中后上肢运动功能障碍的疗效。方法选取2020年9月—2022年2月医院治疗的卒中后上肢运动功能障碍患者100例,随机分为对照组(53例,头穴透刺疗法)和观察组(47例,滋水涵木针法联合头穴透刺疗法),对比两组治疗后临床疗效、Fugl-Meyer运动功能评分上肢部分(Fugl-Meyer assessment-upper extremity,FMA-UE)评分、改良Barthel指数(modified Barthel index,MBI)评分和沃尔夫运动功能测试(Wolf motor function test,WMFT)评分、Brunnstrom偏瘫上肢肌力分级及运动诱发电位皮质潜伏期(cortical latency,CL)和中枢运动传导时间(central motor conduction time,CMCT)值变化。结果观察组治疗有效率较对照组明显较高(P<0.05);两组治疗后FMA-UE评分、MBI评分和WMFT评分较治疗前均明显升高(P<0.05),且观察组较对照组升高更显著(P<0.05);治疗前两组Brunnstrom偏瘫上肢肌力分级间差异无统计学意义(P>0.05);治疗后两组Brunnstrom偏瘫上肢肌力分级较治疗前显著改善(P<0.05);且观察组与对照组相比较改善更明显(P<0.05);两组治疗后CL和CMCT值较治疗前显著降低(P<0.05);且观察组降低更明显(P<0.05)。结论采用滋水涵木针法联合头穴透刺治疗卒中后上肢运动功能障碍具有较好的疗效,能够改善上肢运动功能,提高上肢肌力。