The Unbalance Characteristics And Virtual Dynamic Balancing Technology Of Generator Rotor In Petrochemical Industry

In petrochemical industry, generator is the key parts of energy conversion of fluegas turbine-compressor-generator three units, and it directly restricts the workefficiency of tandem shafting. But on account of three units complex structure, strongmutual coupling of dynamic characteristics, bad work environment, the generatorrotor becomes easily imbalance. In view of the three units continuous operation in theengineering practice, units could not be allowed frequent downtime, so the paperproposes virtual dynamic balancing technology of generator rotor combining with theunbalance vibration characteristic analysis of generator rotor, the main researchcontents include:(1)A certain type of generator rotor dynamics modeling in petrochemical industry.Put generator rotor in the petrochemical industry as the object, introduce the basicstructure, the dynamic equation and its solution of rotor dynamic characteristics, andthen discuss the basic principle of dynamics modeling and the modelling of thegenerator rotor components such as rotor shaft, bearing, silicon steel sheet,conducting bar and so on, establish the finite element dynamic model of the generatorrotor by using the rotor dynamics software DyRoBeS based on the finite element.(2)Generator rotor’s unbalance vibration characteristic simulation analysis andsimulation experimental research. First, based on the established finite element model,carry out the rotor critical speed and vibration mode, vibration response under theunbalanced excitation. Combined with generator rotor dynamic characteristics and theexisting experimental device, design and make the generator rotor simulationexperiment table, and carry out the simulated rotor critical speed and vibration mode,vibration response under the unbalanced excitation. Finally execute rotor unbalancevibration characteristics test experiment of generator rotor simulation test bench.Verified the influence law of rotor vibration under rigid speed range (lower than thecritical speed) and flexible speed range(exceed the critical speed) owing to the rotorunbalance in different axial position (rotor core middle plane and end ring plane) byfinite element simulation analysis.(3)Generator rotor’s virtual dynamic balancing technology and experimentresearch. Mechanics basic principles of virtual balancing of rotor are expounded. The single rotor virtual balancing feasibility experiment without trial weights is carriedout. By DyRoBeS simulation, aggravating influence coefficients of generator simulaterotor are solved. Finally based on virtual dynamic balance principle, carry outgenerator simulate rotor’s dynamic balance test experiment, realize the rotor virtualbalancing without trial weights.In this paper, by analyzing the unbalance vibration characteristic of generatorrotor in petrochemical industry, get the virtual aggravating influence coefficient,realize effective rotor dynamic balance without trial weights. This balancingtechnique reducing the start-shut times, shortening the period of the balance, savingthe dynamic balance cost, is an effective and practical method of field balancingtechnique.