The Research On Power Loss And Heat Balance Of Rotary Motor Of Hybrid Excavator

Motor is generally used to replace hydraulic motor as the rotary drive device in hybrid excavator. Due to the excavator’s large load and limited space, rotary motor usually uses high energy density motor. Owing to the motor’s small size and large power, the rotary motor has the characteristics of big heat and low dissipation ability.Because the motor work in condition of start and break,the heat generated by winding is very large.Based on the special working condition of rotary motor some research from power loss calculation, cooling system design, temperature field solving, thermal equilibrium analysis and structural optimization design ware done.The special condition of rotary motor is analyzed, and two-dimensional electromagnetic analysis model is established by Ansoft software. According to Bertotti iron loss calculation model and reasonable assumptions of the iron loss calculation method is determined and then the iron losses when motor in transition process is calculated.Cooling solutions and cooling system design of rotary motor ware designed on the basis of total power loss which obtained by experiment and simulation. According to the motor’s heat transfer, the equivalent thermal circuit model is established. The model not only can get the motor temperature but also provide theoretical guidance for reduce the temperature rise.The solving process of rotary motor temperature filed whose heat generate is changing is analyzed. Finite element model of1/4motor is established. By steady-state and transient analysis the temperature distribution and instantaneous temperature change process of rotary motor are determined. With this model, the Impact of coolant flow rate flow rate, temperature and heat capacity to motor temperature is studied, which provided the guiding significant for theoretical basis for cooling system design.Make the research of rotary motor thermal equilibrium from lower rotary motor loss and enhance the thermal performance. The research show that reduce the moment of inertia of the motor can not only enhance the performance of rotary excavator but also can reduce the energy consumption of the machine and motor temperature. Parametric model of coolant channel With APDL is built and optimum design is finished which provide theoretical guidance for parameter optimization of the flow channelThe data collection procedure used to the experimental test is programmed in the Labview programming environment. Motor winding losses, steady-state temperature and iron loss are measured by this test system.Analyzed the test data, it proves that the iron loss calculation method which based on the steady-state assumptions and finite element model of motor temperature is feasible.