僅使用單一電流感測器以擴展三相變頻器之電流重建範圍和減少電流諧波的新型混合脈波寬度調變技術

New Hybrid Pulse-Width Modulation Technique to Reduce Current Distortion and Extend Current Reconstruction Range for Three-Phase Inverter using only DC-link Sensor

陳志偉(Chih-Wei Chen)

指導教授 ： 賴炎生

國立臺北科技大學/電資學院/電機工程系研究所/碩士(2012年)

https://doi.org/10.6841/NTUT.2012.00510

摘要

本文主要目的是發展一種新型的脈波寬度調變技術，其僅使用單一電流感測器以擴展三相變頻器的電流重建範圍和減少電流諧波。此新型的脈波寬度調變技術是一種混合式的方法，由空間向量脈波寬度調變技術和不使用零電壓向量之功率開關狀態的脈波寬度調變技術所組成；前者可提供低電流諧波，但變頻器電流重建範圍較窄，相較之下，後者有高電流諧波，但可擴展前者變頻器的電流重建範圍。本文所提出的方法，係於可重建電流區域時，使用空間向量調變技術，以減少電流諧波；在不可重建電流區域，則採用無零電壓向量之功率開關狀態的調變技術，以擴展電流重建範圍，達到三相變頻器的電流重建。
本文利用ALTERA公司所產的現場可規劃邏輯閘陣列(FPGA) EPF10K70RC240-3為控制平台。所使用的感應馬達詳細規格為額定功率750 W、額定轉速1680 RPM、極數4極、頻率60 Hz、額定電壓220/380 V(ê/Y)、額定電流3.1/1.8 A。
由控制平台FPGA為基礎所獲得實測結果可證實，採用本文之電流重建技術，即使在非常低的重建調變指標命令範圍內，也能同時提供變頻器輸出低電流諧波。

關鍵字

脈波寬度調變 ； 變頻器 ； 總諧波失真

並列摘要

The objective of this thesis is to develop a new modulation technique which can reduce the current distortion and extend the current reconstruction range for three-phase inverter using only DC-link sensor. The PWM technique is a hybrid method which consists of space vector modulation method and the PWM method without using null switching states. The former provides low current distortion, however it is with narrower current reconstruction range. In contrast, the later extends the current reconstruction range at the cost of higher current distortion. The proposed method, in the measurable region of space vector modulation method, space vector modulation is used to reduce the current distortion. Moreover, as the modulation range is out of that measurable region, the PWM method without using null switching states is applied to extend the current reconstruction range, and achieve the current reconstruction of the three-phase inverter.
In this thesis, an ALTERA produced Field Programmable Gate Array (FPGA) EPF10K70RC240-3 is used as the control platform. This proposed method for current reconstruction is realized using induction motor (IM). An induction motor with specifications of rated power 750 W, rated speed 1680 RPM, no. of poles 4, rated frequency 60 Hz, rated voltage 220/380 V(ê/Y), rated current 3.1/1.8 A.
Finally, the experimental results will confirm the effectiveness of the proposed method, where the current can be reconstructed even under very low modulation index with low harmonics distortion of inverter output current.

並列關鍵字

Pulse-width Modulation ； Inverter ； Total Harmonic Distortion

參考文獻

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