為了提升工業應用中電機驅動的效率，在市場中大量使用的感應電機其效率提升方案一直是工業控制應用領域中的一個重要研究議題。尤其是低功率應用的市場，例如工業或家用的風機水泵應用，當感應電機運行在低速區時，其效率隨轉速遞減的能耗問題會更嚴重。為了解決此一問題，永磁同步電機和同步磁阻電機近年成為替代感應電機的一個選擇。尤其是IPM永磁同步電機，因為本身具備永磁轉子與磁阻轉矩，因此在體積、效率與響應性上相對於感應電機都有顯著的優勢，因此在原本採用感應電機DTC控制的高精度高響應應用場合，本論文將以MPDTC控制IPM電機做為替代方案。但IPM電機因為成本較高，對於低端的風機水泵類的應用其成本問題將會不利於IM電機的替代工作。因此本文提出同步磁阻電機的純量控制(Scalar control)方案做為IM電機在V/f控制應用場合的替代方案。以此提供IM電機在高低階應用的替代方案以全面改善能耗問題。
為了達成上述的高效能控制方案，電機位置感測的準確度扮演了重要的角色，但安裝電機轉子位置編碼器除了配線和體積問題外，環境溫度和粉塵汙染都會影響編碼器的可靠度，因此本文中提出泛用的永磁同步電機的轉子位置估測演算法來做為無感測MPDTC控制方案之用。
然而不論是IPM同步電機的高效能MPDTC控制或者是同步磁阻電機的MTPA演算法，電機的模型準確度都是相當重要的一環。但IPM同步電機和同步磁阻電機的電感會隨著負載電流而變且定子電阻會隨溫度變化，因此本文提出離線參數估測與基於Popov Hyper Stability理論的在線電機參數估測方法來解決控制過程中的參數變化的問題。
為了驗證本文中的MPDTC與純量控制演算法的可行性，所有的控制性能均先以硬體在線迴路驗證理想工況下的控制性能，最終以動力計系統量測TN曲線與步階響應性能確認控制性能可以滿足工業應用的性能指標，且本文中所提出的同步磁阻純量控制透過與FOC控制的實測對比，驗證此演算控制可實作在低成本的MCU和低切換載波的逆變器上系統中，最終確認同步磁阻電機在低成本的工業應用控制領域取代感應電機的可行性，為感應電機無感測控制應用提供全面的替代方案。

In order to achieve improved performance and efficiency of domestic and industrial applications, there should be an alternative solution to replace induction motors (IMs) which are still widely used for various kinds of applications despite its low efficiency during low speed operation. To provide a total solution to replace IMs, enhanced DTC control of PMSMs is proposed in this dissertation to provide solution for high precise torque control application of IMDTC, and an adaptive scalar control is proposed to replace IM V/f control for cost sensitive applications such as speed control of fan/pump application.
To achieve high control performance for AC motors, the rotor position is very critical. However, position sensors would increase the cost and volume of the motor system due to extra components and wiring. Moreover, most position sensors are sensitive to the ambient temperature and the working conditions. Therefore, a novel position estimation algorithm of sensorless MPDTC for synchronous motor drives is proposed in this dissertation.
In addition, to provide an accurate motor model for MTPA and rotor position estimation algorithm, novel offline and online motor parameter estimation methods are proposed in this dissertation. The proposed parameter estimation algorithm adopts Popov’s hyper stability theorem to estimate accurate motor parameters, such as stator resistance, stator inductance and rotor flux linkage, which are critical for torque and flux estimation. Moreover, online parameter estimation also makes the MTPA loop of SynRM scalar control work properly for high efficiency operation.
Both control algorithms are verified by a hardware in the loop (HIL) emulation platform, and experiment result is also demonstrated using a dynamometer test bench, which therefore proves the feasibility of the proposed methods. In addition to the feasibility, the proposed SynRM scalar control presented in this dissertation can also be implemented using a low cost MCU and PWM inverter with lower carrier frequency, thereby making the low cost AC synchronous motor drive for industrial application feasible and practical。

[1] A. T. de Almeida, F. J. T. E. Ferreira and G. Baoming, "Beyond Induction Motors—Technology Trends to Move Up Efficiency," in IEEE Transactions on Industry Applications, vol. 50, no. 3, pp. 2103-2114, May-June 2014, doi: 10.1109/TIA.2013.2288425.
[2] S. Piriienko et al., "Influence of the Control Strategy on the Efficiency of SynRM Based Small-Scale Wind Generators,"2019 IEEE International Conference on Industrial Technology (ICIT), Melbourne, Australia, 2019, pp. 280-285, doi: 10.1109/ICIT.2019.8755122.
[3] S. Yamamoto, J. B. Adawey and T. Ara, "Maximum efficiency drives of synchronous reluctance motors by a novel loss minimization controller considering cross-magnetic saturation," 2009 IEEE Energy Conversion Congress and Exposition, San Jose, CA, 2009, pp. 288-293, doi: 10.1109/ECCE.2009.5316379.
[4] G. S. Buja and M. P. Kazmierkowski, "Direct Torque Control of PWM Inverter-Fed AC motors - A Survey," in IEEE Transactions on Industrial Electronics, vol. 51, no. 4, pp. 744-757, Aug. 2004.
[5] Tenerz M. Parameter estimation in a permanent magnet synchronous motor. PhD thesis. Sweden: Linköping University; 2011.
[6] K. D. Hoang and H. K. A. Aorith, "Online Control of IPMSM Drives for Traction Applications Considering Machine Parameter and Inverter Nonlinearities," in IEEE Transactions on Transportation Electrification, vol. 1, no. 4, pp. 312-325, Dec. 2015.
[7] D. W. Novotny and T. A. Lipo, "Vector Control and Dynamics of AC Drives," Oxford University Press, Sept. 1996.
[8] I. Takahashi and T. Noguchi, "A New Quick-Response and High-Efficiency Control Strategy of an Induction Motor," in IEEE Transactions on Industry Applications, vol. IA-22, no. 5, pp. 820-827, Sept. 1986.
[9] R. H. Kumar, A. Iqbal and N. C. Lenin, "Review of Recent Advancements of Direct Torque Control in Induction Motor Drives – A Decade of Progress," in IET Power Electronics, vol. 11, no. 1, pp. 1-15, 12 1 2018.
[10] P. Cortes et al., "Guidelines for Weighting Factors Design in Model Predictive Control of Power Converters and Drives," in Proc. IEEE ICIT, Gippsland, Australia, Feb. 10-13, 2009.
[11] V. P. Muddineni and S. R. Sandepudi, "Encoderless Model Predictive Direct Torque Control of Induction Motor Drive Based on MRAS," in 2015 IEEE International Conference on Electrical, Computer and Communication Technologies (ICECCT), Coimbatore, 2015, pp. 1-5.
[12] C. Lin, J. Yu, Y. Lai and H. Yu, "Improved Model-Free Predictive Current Control for Synchronous Reluctance Motor Drives," in IEEE Transactions on Industrial Electronics, vol. 63, no. 6, pp. 3942-3953, June 2016.
[13] Y. Zhang and J. Zhu, "Direct Torque Control of Permanent Magnet Synchronous Motor with Reduced Torque Ripple and Commutation Frequency," in IEEE Transactions on Power Electronics, vol. 26, no. 1, pp. 235-248, Jan. 2011.
[14] F. Niu, B. Wang, A. S. Babel, K. Li and E. G. Strangas, "Comparative Evaluation of Direct Torque Control Strategies for Permanent Magnet Synchronous Machines," in IEEE Transactions on Power Electronics, vol. 31, no. 2, pp. 1408-1424, Feb. 2016.
[15] M. Hasegawa and K. Matsui, "Position Sensorless Control for Interior Permanent Magnet Synchronous Motor Using Adaptive Flux Observer with Inductance Identification," in IET Electric Power Applications, vol. 3, no. 3, pp. 209-217, May 2009.
[16] G. Andreescu, C. I. Pitic, F. Blaabjerg and I. Boldea, "Combined Flux Observer with Signal Injection Enhancement for Wide Speed Range Sensorless Direct Torque Control of IPMSM Drives," in IEEE Transactions on Energy Conversion, vol. 23, no. 2, pp. 393-402, June 2008.
[17] S. Shinnaka, "A New Characteristics-Variable Two-Input/Output Filter in D-Module-Designs, Realizations, and Equivalence," in IEEE Transactions on Industry Applications, vol. 38, no. 5, pp. 1290-1296, Sept.-Oct. 2002.
[18] S. Shinnaka, "New "Mirror-Phase Vector Control" for Sensorless Drive of Permanent-Magnet Synchronous Motor with Pole Saliency," in IEEE Transactions on Industry Applications, vol. 40, no. 2, pp. 599-606, March-April 2004.
[19] S. Shinnaka, "New "D-State-Observer"-Based Vector Control for Sensorless Drive of Permanent-Magnet Synchronous Motors," in IEEE Transactions on Industry Applications, vol. 41, no. 3, pp. 825-833, May-June 2005.
[20] I. Boldea and S. C. Agarlita, "The Active Flux Concept for Motion-Sensorless Unified AC Drives: A Review," in International Aegean Conference on Electrical Machines and Power Electronics and Electromotion, Joint Conference, Istanbul, 2011, pp. 1-16.
[21] I. Boldea, M. C. Paicu, G. Andreescu and F. Blaabjerg, "“Active Flux” DTFC-SVM Sensorless Control of IPMSM," in IEEE Transactions on Energy Conversion, vol. 24, no. 2, pp. 314-322, June 2009.
[22] G. H. B. Foo and M. F. Rahman, "Direct Torque Control of an IPM-Synchronous Motor Drive at Very Low Speed Using a Sliding-Mode Stator Flux Observer," in IEEE Transactions on Power Electronics, vol. 25, no. 4, pp. 933-942, April 2010.
[23] M. H. Bierhoff, "A General PLL-Type Algorithm for Speed Sensorless Control of Electrical Drives," in IEEE Transactions on Industrial Electronics, vol. 64, no. 12, pp. 9253-9260, Dec. 2017
[24] R. Zhao, Z. Xin, P. C. Loh and F. Blaabjerg, "A Novel Flux Estimator Based on Multiple Second-Order Generalized Integrators and Frequency-Locked Loop for Induction Motor Drives," in IEEE Transactions on Power Electronics, vol. 32, no. 8, pp. 6286-6296, Aug. 2017.
[25] A. H. Wijenayake and P. B. Schmidt, "Modeling and Analysis of Permanent Magnet Synchronous Motor by Taking Saturation and Core Loss Into Account," in Proceedings of Second International Conference on Power Electronics and Drive Systems, Singapore, 1997, pp. 530-534 vol. 2.
[26] A. Timbus, M. Liserre, R. Teodorescu, P. Rodriguez and F. Blaabjerg, "Evaluation of Current Controllers for Distributed Power Generation Systems," in IEEE Transactions on Power Electronics, vol. 24, no. 3, pp. 654-664, March 2009.
[27] S. J. Underwood and I. Husain, "Online Parameter Estimation and Adaptive Control of Permanent-Magnet Synchronous Machines," in IEEE Transactions on Industrial Electronics, vol. 57, no. 7, pp. 2435-2443, July 2010.
[28] Y. Gao, R. Qu, Yu Chen, Jian Li and Wei Xu, "Review of Off-Line Synchronous Inductance Measurement Method for Permanent Magnet Synchronous Machines," in 2014 IEEE Conference and Expo Transportation Electrification Asia-Pacific (ITEC Asia-Pacific), Beijing, 2014, pp. 1-6.
[29] Y. Inoue, Y. Kawaguchi, S. Morimoto and M. Sanada, "Performance Improvement of Sensorless IPMSM Drives in a Low-Speed Region Using Online Parameter Identification," in IEEE Transactions on Industry Applications, vol. 47, no. 2, pp. 798-804, March-April 2011
[30] Y. Shi, K. Sun, L. Huang and Y. Li, "Online Identification of Permanent Magnet Flux Based on Extended Kalman Filter for IPMSM Drive with Position Sensorless Control," in IEEE Transactions on Industrial Electronics, vol. 59, no. 11, pp. 4169-4178, Nov. 2012.
[31] K. Liu, Q. Zhang, Z. Zhu, J. Zhang, A. Shen and P. Stewart, “Comparison of Two Novel MRAS Based Strategies for Identifying Parameters in Permanent Magnet Synchronous Motors”, in International Journal of Automation and Computing, vol. 7, Issue 4, pp 516–524, November 2010.
[32] Y. Chen, F. Zhou, X. Liu and E. Hu, "Online Adaptive Parameter Identification of PMSM Based on the Dead-time Compensation,” in International Journal of Electronics, vol. 102, Issue 7, pp. 1132-1150, 2015.
[33] A. Shinohara, Y. Inoue, S. Morimoto and M. Sanada, "Direct Calculation Method of Reference Flux Linkage for Maximum Torque per Ampere Control in DTC-Based IPMSM Drives," in IEEE Transactions on Power Electronics, vol. 32, no. 3, pp. 2114-2122, March 2017.
[34] D. Shmilovitz, "On the Definition of Total Harmonic Distortion and Its Effect on Measurement Interpretation," in IEEE Transactions on Power Delivery, vol. 20, no. 1, pp. 526-528, Jan. 2005.
[35] M. N. Ibrahim, P. Sergeant and E. M. Rashad, "Synchronous Reluctance Motor Performance Based on Different Electrical Steel Grades," in IEEE Transactions on Magnetics, vol. 51, no. 11, pp. 1-4, Nov. 2015, Art no. 7403304, doi: 10.1109/TMAG.2015.2441772.
[36] P. R. Ghosh, A. Das and G. Bhuvaneswari, "Performance comparison of different vector control approaches for a synchronous reluctance motor drive," 2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA), Roorkee, 2017, pp. 320-325, doi: 10.1109/CERA.2017.8343348.
[37] S. M. Ferdous, P. Garcia, M. A. M. Oninda and M. A. Hoque, "MTPA and Field Weakening Control of Synchronous Reluctance motor," 2016 9th International Conference on Electrical and Computer Engineering (ICECE), Dhaka, 2016, pp. 598-601, doi: 10.1109/ICECE.2016.7853991.
[38] P. D. C. Perera, F. Blaabjerg, J. K. Pedersen and P. Thogersen, "A sensorless, stable V/f control method for permanent-magnet synchronous motor drives," in IEEE Transactions on Industry Applications, vol. 39, no. 3, pp. 783-791, May-June 2003, doi: 10.1109/TIA.2003.810624.
[39] G. Jalali, S. Ahmed, H. Kim and Z. Pan, "Instability detection and protection scheme for efficiency optimized v/f driven synchronous reluctance motors (SynRM)," 2016 IEEE Energy Conversion Congress and Exposition (ECCE), Milwaukee, WI, 2016, pp. 1-6, doi: 10.1109/ECCE.2016.7855206.
[40] M. Cacciato, A. Consoli, G. Scarcella and G. Scelba, "A novel efficiency optimization scalar control technique for industrial IPMSM drives," 2010 IEEE International Symposium on Industrial Electronics, Bari, 2010, pp. 1181-1186, doi: 10.1109/ISIE.2010.5636642.
[41] P. Niazi, H. A. Toliyat and A. Goodarzi, "Robust Maximum Torque per Ampere (MTPA) Control of PM-Assisted SynRM for Traction Applications," in IEEE Transactions on Vehicular Technology, vol. 56, no. 4, pp. 1538-1545, July 2007, doi: 10.1109/TVT.2007.896974.
[42] Z. Tang, X. Li, S. Dusmez and B. Akin, "A New V/f-Based Sensorless MTPA Control for IPMSM Drives," in IEEE Transactions on Power Electronics, vol. 31, no. 6, pp. 4400-4415, June 2016, doi: 10.1109/TPEL.2015.2470177.
[43] S. Sue, T. Hung, J. Liaw, Y. Li and C. Sun, "A new MTPA control strategy for sensorless V/f controlled PMSM drives," 2011 6th IEEE Conference on Industrial Electronics and Applications, Beijing, 2011, pp. 1840-1844, doi: 10.1109/ICIEA.2011.5975891.
[44] L. Cheng and M. Tsai, "Enhanced Model Predictive Direct Torque Control Applied to IPM Motor with Online Parameter Adaptation," in IEEE Access, vol. 8, pp. 42185-42199, 2020, doi: 10.1109/ACCESS.2020.2977057
[45] L. -J. Cheng and M. -C. Tsai, "Robust Scalar Control of Synchronous Reluctance Motor with Optimal Efficiency by MTPA Control," in IEEE Access, vol. 9, pp. 32599-32612, 2021, doi: 10.1109/ACCESS.2021.3060436.