基于PLC控制桥式起重机变频系统的设计毕业设计论文_精品.doc

基于PLC控制桥式起重机变频系统的设计 摘要：桥式起重机作为物料搬运系统中一种典型设备，在企业生产活动中应用广泛作用显著，因此对于提高桥式起重机的运行效率，确保运行的安全可靠性，降低物料搬运成本是十分重要。传统的桥式起重控制系统主要采用继电器接触器进行控制，采用交流绕线串电阻的方法进行启动和调速，这种控制系统存在可靠性差，操作复杂，故障率高。电能浪费大，效率低等缺点。 针对桥式起重机控制系统中存在的上述问题，把可编程序控制器和变频器应用于桥式起重机控制系统上，并进行了较详细的设计。 1.根据桥式起重机的运行特点，桥式起重机控制系统采用PLC控制系统、变频调速系统等组成。 2.PLC系统采用三菱公司产品，能控制起重机大车、小车的运行方向和速度;吊钩的升、降方向及速度，同时能检测各个电机故障现象，减小了传统继电—接触式控制系统的中间环节。减少了硬件和控制线，极大提高了系统的稳定性，可靠性。 3. 实验表明，采用PLC该控制系统，使桥式起重机工作可靠，使用方便，同时具有动态显示的功能，节能效果好明显。 关键词: 可编程序控制器；变频调速；桥式起重机；电气控制系统 Frequency?of?Bridge?Crane?Based?on? PLC?Control System?Design Abstract：The bridge crane carries a kind of typical equipment in the supplies system，so it have extensive function in the activity of Producing enterprise，so it important improve the bridge crane operational efficiency，guarantee the safe reliability to be operated，reduce the cost of the supplies carrying. But the traditional bridge crane control system mainly adopts relay and contactor to control bridge crane，adopt the methods of Wire winding bunch of resistance to start and adjust speed of motor，the control system have many disadvantages， for example: dependability is bad，it is complicated to operate，fault rate is high .the electric energy is wasted greatly，efficiency is low. To the question that exist in the bridge crane control system，the Paper apply Programmable Controller and frequency converter on control system of bridge crane，have candied on deeper research . Irrelevant respects. 1. According to the operation characteristic of bridge crane，bridge crane control system adopt PLC control system and frequency conversion system. 2. PLC system adopts the Mitsubishi Company Products，can control the crane cart，ear operation direction and change speed ;To rise，lower liver direction and change speed，can measure each motor trouble Phenomenon，have reduced traditional electricity-Contact-type control system of intermediate link . it reduce the hardware and control line，has improved systematic stability ，dependability greatly .