| Based on the background of ministry of education innovation team project, educationdepartment of Liaoning province innovation team project and project of Fushun Coal MineMotor Manufacturing Ltd., a1140V/75kW explosion-proof integrative motor as researchobject, aimed at volume problem of driving system resulting from narrow mine working spaceand after the variable-frequency speed control system was integrated with motor highly, andthe problem that speed estimation value of speed sensorless vector control system is easilyaffected by measuring parameters, and system cost problems, research on speed controlsystem power design and speed estimation of explosion-proof integrative motor had beencarried out. The main contents of this thesis include the following aspects:In order to improve the system integration, reduce volume and cost of explosion-proofintegrative motor,Based on power electronics modeling, the power part of variable-frequencyspeed control system was spreading design. An analytical method to calculate the buscapacitance parameters of inverter was put forward, and a detailed analysis was made aboutoutput waveform of rectifier in a cycle considering interaction between the voltage drop,ripple current and system stability, and the bus capacitance values were calculatedby Newton-Raphson method. And it gave the simulation and calculation scheme of inputcurrent, voltage of SKSG, voltage of bus capacitance, ripple current of bus capacitance andoutput current.For the design process of explosion-proof integrative motor is restricted by volume andtemperature?the accurate calculation of the rectifier and inverter loss is important fordesigning speed regulation system water-cooled radiator of explosion-proof integrative motoraccurately and selecting IGBT reasonable. Based on this,A calculation scheme to calculatecontrolled rectifier and inverter IGBT loss was put forward based on analytical method. In theprocess of implementation, the impact of gate drive resistance, DC bus voltage, temperature,junction temperature on loss of IGBT was considered comprehensively. A calculation methodof inverter IGBT and Diode conduction loss, switch loss, total loss, temperature difference andjunction temperature based on SVPWM modulation algorithm was given. Considering thecharacteristics that IGBT loss and junction temperature influence each other, by using customthermal circuit model, put forward an iteration algorithm in the initial condition of the ambienttemperature, and gave the junction temperature of IGBT, shell temperature and temperature curve of the radiator finally. The influence of the DC bus voltage, the gate drive resistors, theenvironment temperature on rectifier and inverter loss and temperature rise calculation werequantitatively analyzed. On this basis, a water-cooling radiator had been designed, and losscalculation of main heating parts of the explosion-proof integrative motor was conducted, toanalysis heat flux by applying temperature simulation software, simulation and experimentalresults had been compared.Based on the co-simulation platform of MATLAB and Simplorer/Ansoft, onlineadjustment was conducted on current and speed regulator parameters of speed control system,optimized correct PI regulator parameters through programs to save tuning time of PIparameters in system experiment.Vector control program of speed sensorless for speed control system of explosion-proofintegrative motor based was design on DSP2812. For the problems that coal mine power gridvoltage fluctuation was large, and collecting dates were vulnerable to volatility of measureparameters, thus leading to the increase of the speed estimation error in the speed estimationprocess, a kind of speed sensorless control strategy of induction motor based on fuzzy kalmanfiltering was proposed. Recursive and online amend measurement noise covariance matrix bymonitoring the ratio of the theoretical and actual residual, to make it approach the true noiselevel gradually, so that the filter can perform optimal estimation and improve estimationaccuracy.Structure of the explosion-proof integrative motor was design, and an1140V/75kWexplosion-proof integrative motor was made. Experiment platform to conduct experimentalstudy on it under no-load and load conditions respectively was built. Mainly including: switchcharacteristics experiment under no-load condition, temperature rise experiment underdifferent rotation speed and load torque, PI parameters regulation experiment, speed suddenlyrising and falling, current suddenly disturbances such as speed estimation experiments.Correctness and feasibility of the proposed scheme and the designed explosion-proofintegrative motor in this thesis had been verified. |
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