Font Size: a A A

Efficiency Optimization Control Methods Of Interior Permanent Magnet Synchronous Motors Drive System For Urban Rail Traction

Posted on:2011-03-13Degree:DoctorType:Dissertation
Country:ChinaCandidate:Y F ShengFull Text:PDF
GTID:1102330335989027Subject:Control Science and Engineering
Abstract/Summary:PDF Full Text Request
More and more attentions have been paid on urban rail transit as it relieves pressure of urban transportation, unexampled advantages of which are large passenger transport volume, safe and reliable, little disturbance, and so on, compared with other means of urban passenger transportation. Electric traction has become the development direction of traction power with the following features:high power, fast speed, high efficiency, strong overload capacity. The interior permanent magnet synchronous motor(IPMSM) can make use of the magnetoresistive effect to improve its efficiency and speed characteristics, has the advantages of small size, large output torque in the low speed, minor magnetic air gap, so that it is especially suitable for traction motor of urban rail transit. Extension attentions have been focused on the problem operating energy consumption in the system of electric traction, and energy-saving control of traction system becomes a major research direction in the system of urban rail traction. Chosen the IPMSM drive system of urban rail traction as research object, combined the operating characteristic of urban rail transit, the relevant theory and method to IPMSM efficiency optimization and control strategy are mainly studied in paper. The theoretical and experimental basis is provided for application of energy saving and lower consumption in the drive system of IPMSM for urban rail traction.The structure and principle of IPMSM are firstly analyzed, its mathematical models are deduced in the different coordinate system, and respectively equivalent circuits are obtained. The switch frequency optimization method is proposed based on analysing to the characteristic of SVPWM voltage source inverter and harmonic component of SVPWM output waveform. The hysteresis band is adaptively controlled by the speed and load changing rate and the optimum distribution strategy of zero voltage vector is adopted to suppress harmonic waveform in the output voltage and current of inverter, reduce core and copper losses produced by harmonic voltage and current, and improve system efficiency and dynamic performance. Based on the analysis to drive system's operating characteristic and motor's state equation, the control strategy of optimal flux/speed and efficiency optimization instantaneous power are presented for the drive system of urban rail traction motor during the transiently operating process of accelerating and braking region.It can fully develop the ability of output torque and can control the stator flux and motor speed to attain minimum operating loss of IPMSM and improve operating efficiency in the control strategy of optimal flux/speed. The instantaneous power control strategy is proposed based on the instantaneous power theory of three phase circuit. Instantaneously input active and reactive power are changed by the control of stator field's amplitude and position angle to improve the system efficiency, torque output capability, and response speed.When the drive system of urban rail traction motor runs at constant speed (cruising operation), its operating state is approximated to be steady. The efficiency optimization control in the drive system of urban rail traction motor is solved at steadily operating state. Analyzed the relation among various losses, excitation current, and speed, the loss model of IPMSM is built. The minimum excitation current control method is proposed to attained minimum electromagnetic losses. The minimum loss and maximum output torque are achieved by the minimum excitation current control, and the operating efficiency of motor and dynamic performance of system are improved.The loss model efficiency optimization control method of IPMSM is largely dependent on motor parameters and is hard to be realized. The golden section method and fuzzy logic search technique are researched. The integrated search technology is proposed to realize online efficiency optimization control for drive system of urban rail traction motor. Simulation results are proved that the traction system energy consumption is reduced, the traction system efficiency is improved effectively, torque ripple is reduced, and robustness is improved by the method.The embedded microcontroller STM32F103 of ST corporation is used for the host control chip, the C programming language is applied for control software, and the experimental platform is constructed for efficiency optimization control system of urban rail traction IPMSM. Design and realization on hardware circuit of overall system and partial software are introduced in detail. The efficiency optimization control experiments of IPMSM drive system are performed on the platform during the transiently operating process of accelerating/braking region and steady-state operating process of constant speed (cruising operation). The validity of the proposed strategy is proved by the experimental results.
Keywords/Search Tags:Urban rail transit, interior permanent magnet synchronous motor, efficiency optimization control, integrated search technology, instantaneous power control
PDF Full Text Request
Related items