適用於微型氣渦輪機之市電併聯電路研製

Design and Implementation of a Grid-tied Circuit for Micro Turbine Generator

微型氣渦輪機其容量從數十千瓦到數百千瓦，適合安裝於大電力用戶或工廠中，屬於分散型發電系統之一種。微型氣渦輪機受到機組足寸限制，渦輪機運轉速度常高達每分鐘數十萬轉，導致發電機之輸出電頻率亦高達數千赫茲，因此微型氣渦輪機系統需於發電機之輸出端加入一級電力併聯電路。本文即在研究適用於微型氣渦輪機之市電併聯電路設計法，其中規劃以電流迴授法，完成其市電併聯供電控制，同時亦在發電機的並聯供電模式中，融入負載功因矯正及主動濾波功能，使氣渦輪機的並聯運轉兼具負載管理概念，增加氣渦輪發電機組之經濟運轉價值。由電腦模擬及系統測試結果顯示，本文所提之方法確具可行性，該研究成果應具實務參考價值。

The MTG is one of distributed generations. The capacity ranges from several kW up to MW, which can be suitably installed at an industrial plant. The MTG is composed of a gas turbine, compressor, and A Cgenerator. They are inertia welded on a single shaft to simplify the mechanical structure of the system. Because the shaft turns at the speed of the turbine, the generator provides high frequency A C electricity. This requires a rectifier and an inverter to interface between the A C generator and the utility network. In this paper, based on the paradigm of current control, a new approach to control the power converter for an MTG will be proposed. By using the developed method, the micro-turbines can be driven as a parallel generator, where the operations of the proposed generator not only can be used to output the sinusoidal current with high power factor, but also is applied for active power filter, helping mitigating the power quality issues caused by the wide uses of nonlinear loads in the demand side. The method proposed in this paper is examined under various scenarios. Test results are not only beneficial for the design of micro-turbines, but also help increase the security and reliability of a future deregulation power system.