Instantaneous Power Balancing Control for an Integrated Rectifier/Inverter Fed Three-Phase Induction Servo System with Unity Power Factor

• Main Authors: Liao Juinne-Ching, 廖峻慶
• Other Authors: Yeh Sheng-Nian
• Format: Others
• Language: zh-TW
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/41320376480854219580

博士 === 國立臺灣科技大學 === 電機工程系 === 88 === This dissertation presents a novel method of instantaneous power control for the integrated rectifier/inverter fed three-phase induction servo motor. Two identical pulse-width modulation (PWM) converters are used to serve as power regulator with unity power factor and servo motor drive using indirect field-oriented control, respectively. By introducing the synchronous rotating-frame current regulators and the voltage decouplers, both the input and output currents of the integrated system are characterized by fast current response and low harmonic distortion. A novel input-output instantaneous power balancing approach is proposed to improve the dynamic response of input power regulation during load variation in order to minimize the dc-link capacitance. The analytic power models are established for the different input power control methods. The effects of the dynamic responses using different input power control methods are compared and the systematic design and analysis of the proposed method are also presented. The proposed system is implemented with a 1.5kW induction motor. The experimental results show that a near-unity power factor is achieved and the regenerative power can be sent back to the source while motor is braking. By the feedforward power control strategy, only a small dc capacitance about 470 mf is needed for the dc-link capacitor. The dynamic dc-link voltage response of the proposed power estimation method is superior to that of the power feedback method in the transient state. Finally, the analytic results obtained are verified experimentally.