具可重組能源支撐機構以開關式磁阻發電機為主之直流微電網

SWITCHED-RELUCTANCE GENERATOR BASED DC MICROGRID WITH RECONFIGURABLE ENERGY SUPPORT MECHANISM

盧旻澤(Min-Ze Lu)

指導教授 ： 廖聰明

國立清華大學/電機資訊學院/電機工程學系所/博士(2022年)

摘要

本論文旨在開發一具可重組能源支撐機構以風力開關式磁阻發電機為主之直流微電網。首先建立一變頻感應馬達驅動之開關式磁阻發電機及其後接非對稱橋式轉換器，採磁滯電流控制以具快速電流追控性能，且經量化設計之電壓控制器，獲得調節良好之48伏直流標稱輸出電壓。為減少開關式磁阻發電機之反電動勢影響，提出考慮最大可操作功率之換相移位策略，可正常操作於廣速度及負載範圍。另外，再提出一些增能探究，包含：(i) 換相移位對直流鏈電壓漣波之影響，可間接降低發電機之產生轉矩漣波；(ii) 發電機之轉子位置估測，包含換相時刻及窗角設定；以及(iii) 單一相斷路之發電容錯能力。
為建立微電網共同直流匯流排電壓(400V)，建構一交錯式直流-直流昇壓轉換器。除良好設計之電流及電壓回授控制器外，加入一輸入電壓前饋控制器，於風力發電機輸出電壓變動下，增快電壓之調節響應速度。為增進微電網之供應可靠性，安裝一包含超電容、電池及開關式磁阻馬達驅動飛輪之混合儲能系統。並裝配一基於維也納切換式整流器之插入式能源支撐機構，以接收可取得之直流、單相及三相交流電源。當風能不足時，微電網可藉此安排，在直流匯流排獲得能源支援。
接著，提出一可重組之交錯式昇壓介面轉換器。藉於不同並接轉換器數量進行之穩態特性量測，建立一依速度切換並接數量之交錯式昇壓轉換器，可在廣速度範圍下保有高能源轉換效率。於低風速，甚至風渦輪機停機時，交錯式轉換器可重組，以擷取輸入外部電源。此外，為拓展所建直流微電網之能源輸入多樣性，再經所開發之交錯式轉換器建立太陽光伏系統。在微電網之測試負載安排上，採用單相三線負載變頻器模擬家用負載。另外，本論文亦從事所建微電網與電動車開關式磁阻馬達驅動系統之互聯雙向操作。所有所建電力電路均以模擬及量測結果驗證評估之。

關鍵字

開關式磁阻電機 ； 風力發電機 ； 太陽光伏 ； 直流微電網 ； 超電容 ； 電池 ； 飛輪 ； 單相三線變頻器 ； 插入式機構 ； 切換式整流器 ； 可重組架構 ； 換相移位 ； 位置估測 ； 電壓控制 ； 電流控制 ； 強健控制 ； 前饋控制 ； 車輛至微電網 ； 微電網至車輛

並列摘要

This dissertation develops a wind switched-reluctance generator (SRG) based direct current (DC) microgrid with reconfigurable energy support mechanism. An inverter-fed induction motor (IM) driven SRG with followed asymmetric bridge converter is first established. The hysteresis current control is adopted to possess fast current tracking performance, while the voltage controller is quantitatively designed for obtaining well-regulated nominal DC 48V output voltage. To reduce the effects from back electromotive force (back-EMF) of the SRG, the commutation shifting approach considering maximum operable power is employed, which makes the wind SRG be normally operated over wide speed and load ranges. In addition, some other performance enhancements to the SRG being made include: (i) influence of commutation shift to the DC-link voltage ripple, which may indirectly reduce developed torque ripple of the SRG; (ii) algorithm of position estimation to the SRG including commutation instant and dwell angle settings; and (iii) fault-tolerant capability as one phase is disconnected.
To establish the microgrid common DC-bus voltage (400V), an interleaved DC-DC boost converter is constructed. In addition to the well-designed current and voltage feedback controllers, an input voltage feedforward controller is added to yield fast voltage regulation response against the fluctuated SRG output voltage. To enhance the power supplying reliability, the hybrid energy storage system (ESS) including supercapacitor, battery and switched-reluctance motor (SRM)-driving flywheel is installed. And a Vienna switch-mode rectifier (SMR) based plug-in energy support mechanism is equipped to accept the available DC, single-phase and three-phase alternating current (AC) sources. As the wind energy is insufficient, the microgrid can be supported energy at its DC bus from these arrangements.
Next, a reconfigurable interleaved boost interface converter is proposed. Through the measurement of steady-state characteristics under different converter cell numbers, the speed-dependent interleaved boost converter is established to preserve high energy conversion efficiency over wide speed range. Under lower wind speed, even the wind turbine is halted, the interleaved converter can be reconfigured to extract power from external sources. To expand the diversity of the established DC microgrid, the photovoltaic (PV) system is further established using the developed interleaved converter. As to the test load arrangement, the single-phase three-wire (1P3W) load inverter is adopted to emulate household appliances. In addition, an electric vehicle (EV) SRM drive is cooperated to the DC microgrid to achieve the vehicle-to-microgrid (V2M) and microgrid-to-vehicle (M2V) operations. All the established power stages are evaluated via the given simulated and measured results.

並列關鍵字

Switched-reluctance machine ； wind generator ； photovoltaic ； DC microgrid ； supercapacitor ； battery ； flywheel ； 1P3W inverter ； plug-in mechanism ； switch-mode rectifier ； reconfigurable schematic ； commutation shift ； position estimation ； voltage control ； current control ； robust control ； feedforward control ； vehicle-to-microgrid ； microgrid-to-vehicle

參考文獻

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