Design and Implementation of 100 kVA D-Σ Digital Controlled Multi-Function Inverter

• Main Authors: Wang, Chun Ping, 王鈞平
• Other Authors: Wu, Tasi Fu
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/ju97r9

碩士 === 國立清華大學 === 電機工程學系 === 104 === This thesis presents design and implementation of a 100 kVA division-summation (D-Σ) digital controlled multi-function inverter. A three-phase four-wire half-bridge circuit structure is adopted for high power transferring and the microcontroller Renesas RX62T is the control center of the system. The inverter can be operated in grid-connected mode and ac-voltage regulation mode. In the ac-voltage regulation mode, the voltage tracking with D-Σ digital control, including load impedance estimation, is used for the inverter to output stable three-phase sinusoidal voltage. In the grid-connected mode, the current tracking also with D-Σ digital control is utilized. Therefore, the inverter is able to adjust the output of active power and reactive power to stabilize grid voltage and grid frequency. Regarding the control of the inverter, D-Σ digital control avoids conventional abc to qd frame transformation. Consequently, derivation of the plant and control law can be significantly simplified. The controller with D-Σ digital control is designed to eliminate the effects caused by the variation of dc bus voltage, switching frequency, and inductance. D-Σ digital control takes into account the inductance variation. It has the benefits such as allowance of wide inductance variation and reduction of core size and cost. Moreover, an SPWM combined with D-Σ digital control separates a three-phase inverter into three single inverters and reduces complexity of control. Finally, simulated results and experimental results have verified the feasibility of the inverter system.