DOI QR코드

DOI QR Code

Enhancing the Accuracy for the Open-loop Resolver to Digital Converters

  • Received : 2017.04.10
  • Accepted : 2017.08.23
  • Published : 2018.01.01

Abstract

In this study, improvements for error correction, speed, position, and rotation calculation algorithms have been proposed to be used in resolver to digital conversion (RDC) systems. The proposed open-loop system drives the resolver and uses the output signals of the resolver signal to estimate the real time position, the instant speed, and the rotation count with high resolution and accuracy even at high speeds and noise. The proposed solution implements strong features of both closed and open loop based systems while eliminating their weak points. The improvements proposed is resistant to noise owing to digital FIR filter and data averaging techniques. The implementation used for proof of concept is implemented on a hardware using an FPGA and configurable to be used by any resolver.

E1EEFQ_2018_v13n1_192_f0001.png 이미지

Fig. 1. Cross-section of a resolver [23]

E1EEFQ_2018_v13n1_192_f0002.png 이미지

Fig. 2. Resolver signals [22]

E1EEFQ_2018_v13n1_192_f0003.png 이미지

Fig. 3. Block diagram of the general RDC system

E1EEFQ_2018_v13n1_192_f0004.png 이미지

Fig. 4. Block diagram of the proposed RDC system

E1EEFQ_2018_v13n1_192_f0005.png 이미지

Fig. 5. Block diagram of the proposed FPGA design

E1EEFQ_2018_v13n1_192_f0006.png 이미지

Fig. 6. FIR filter magnitude response

E1EEFQ_2018_v13n1_192_f0007.png 이미지

Fig. 7. Position error with and without the FIR filter for aconstant motor

E1EEFQ_2018_v13n1_192_f0008.png 이미지

Fig. 8. Position error with and without data validation

E1EEFQ_2018_v13n1_192_f0009.png 이미지

Fig. 9. Error with and without data averaging for astationary motor at π/8

E1EEFQ_2018_v13n1_192_f0010.png 이미지

Fig. 10. Speed (rad/38μs) for a 10000 rpm rotating motor

E1EEFQ_2018_v13n1_192_f0011.png 이미지

Fig. 11. Data control, rotation sense and position estimatorblock algorithm

E1EEFQ_2018_v13n1_192_f0012.png 이미지

Fig. 12. Position error for a 70Hz ±π sine position input atthe CORDIC and the system output

E1EEFQ_2018_v13n1_192_f0013.png 이미지

Fig. 13. Position error for a 10000 rpm rotating motor atthe CORDIC and the system output

E1EEFQ_2018_v13n1_192_f0014.png 이미지

Fig. 14. Position input, estimated position output androtation count for a motor rotating at 20000 rpm

E1EEFQ_2018_v13n1_192_f0015.png 이미지

Fig. 15. Simulation block diagram

E1EEFQ_2018_v13n1_192_f0016.png 이미지

Fig. 16. The resolver mathematical model

Table 1. Speed calculation errors for different speeds

E1EEFQ_2018_v13n1_192_t0001.png 이미지

Table 2. Properties of the proposed method

E1EEFQ_2018_v13n1_192_t0002.png 이미지

References

  1. C. Mohan, R. Sivappagari, and N. R. Konduru, "Review of RDC Soft Computing Techniques for Accurate Measurement of Resolver Rotor Angle," Sensors & Transducers, vol. 150, no. 3, pp. 1-11, 2013.
  2. C. H. Yim, I. J. Ha, and M. S. Ko, "A resolver-todigital conversion method for fast tracking," IEEE Trans. Ind. Electron., vol. 39, no. 5, pp. 369-378, 1992. https://doi.org/10.1109/41.161468
  3. A. O. Di Tommaso, and R. Miceli, "A new high accuracy software based resolver-to-digital converter," in IECON Proceedings (Industrial Electronics Conference), 2003, vol. 3, pp. 2435-2440.
  4. R. Hoseinnezhad, and P. Harding, "A novel hybrid angle tracking observer for resolver to digital conversion," in Proceedings of the 44th IEEE Conference on Decision and Control, and the European Control Conference, CDC-ECC '05, 2005, vol. 2005, pp. 7020-7025.
  5. J. Onno, K. Heiko, and S. Marcel, "FPGA Based Resolver to Digital Converter Using Delta-Sigma Technology," Delta, pp. 931-936, 2006.
  6. K. Bouallaga, L. Idkhajine, A. Prata, and E. Monmasson, "Demodulation methods on fully FPGAbased system for resolver signals treatment," in 2007 European Conference on Power Electronics and Applications, EPE, no. 1, 2007.
  7. Analog Devices, "Variable Resolution, 10-Bit to 16- Bit R/D Converter with Reference Oscillator," AD2S1210 datasheet, 2010.
  8. Analog Devices, "Variable Resolution, Monolithic Resolver-to-Digital Converter," AD2S80A datasheet, 2014.
  9. L. Idkhajine, a. Prata, E. Monmasson, K. Bouallaga, and M. W. Naouar, "System on Chip controller for electrical actuator," IEEE Int. Symp. Ind. Electron., pp. 2481-2486, 2008.
  10. L. Ben-Brahim, and M. Benammar, "A new PLL method for resolvers," in 2010 International Power Electronics Conference ECCE Asia, IPEC 2010, no. 4, pp. 299-305, 2010.
  11. J. Bergas-jane, S. Member, C. Ferrater-simon, G. Gross, R. Ramírez-pisco, S. Galceran-arellano, and J. Rull-duran, "High-Accuracy All-Digital Resolver-to- Digital Conversion," IEEE Trans. Ind. Electron., vol. 59, no. 1, pp. 326-333, 2012. https://doi.org/10.1109/TIE.2011.2143370
  12. D. A. Khaburi, "Software-based resolver-to-digital converter for DSP-based drives using an improved angle-tracking observer," IEEE Trans. Instrum. Meas., vol. 61, no. 4, pp. 922-929, 2012. https://doi.org/10.1109/TIM.2011.2179825
  13. N. Noori, and D. A. Khaburi, "A new software-based method for rotor angle calculation," in the 5th Power Electronics, Drive Systems and Technologies Conf., Tehran, pp. 305-310, 2014.
  14. Y.-H. Kim, and S. Kim, "Software resolver-to-digital converter for compensation of amplitude imbalances using D-Q transformation," J Electr Eng Technol Vol. 8, No. 6, pp. 1310-1319, 2013. https://doi.org/10.5370/JEET.2013.8.6.1310
  15. M. Benammar, L. Ben-Brahim, and M. A. Alhamadi, "A novel resolver-to-$360^{\circ}$ linearized converter," IEEE Sens. J., vol. 4, no. 1, pp. 96-101, 2004. https://doi.org/10.1109/JSEN.2003.820317
  16. M. Benammar, L. Ben-Brahim, and M. A. Alhamadi, "A high precision resolver-to-DC converter," IEEE Trans. Instrum. Meas., vol. 54, no. 6, pp. 2289-2296, 2005. https://doi.org/10.1109/TIM.2005.858135
  17. M. Benammar, L. Ben-Brahim, M. A. Alhamadi, and M. El-Naimi, "A Novel Converter for Sinusoidal Encoders," in IEEE Sensors Conference, pp. 1415- 1418, 2006.
  18. L. Ben-Brahim, M. Benammar, M. A. Alhamadi, N. A. Al-Emadi, and M. A. Al-Hitmi, "A new low cost linear resolver converter," IEEE Sens. J., vol. 8, no. 10, pp. 1620-1627, 2008. https://doi.org/10.1109/JSEN.2008.928924
  19. A. Kaewpoonsuk, W. Petchmaneelumka, A. Rerkratn, S. Tammaruckwattana, and V. Riewruja, "A novel resolver-to-DC converter based on OTA-based inversesine function circuit," in Proceedings of the SICE Annual Conference, pp. 609-614, 2008.
  20. L. Ben-Brahim, M. Benammar, and M. a. Alhamadi, "A resolver angle estimator based on its excitation signal," IEEE Trans. Ind. Electron., vol. 56, no. 2, pp. 574-580, 2009. https://doi.org/10.1109/TIE.2008.2002719
  21. M. Benammar, M. Bagher, and M. Al Kaisi, "Novel linearizer for tangent/cotangent converter," in 2009 16th IEEE International Conference on Electronics, Circuits and Systems, ICECS 2009, pp. 575-578, 2009.
  22. H. Schmid, "Direct resolver to digital converter," U.S. Patent 5 912 638, June 15, 1999.
  23. Texas Instruments, Appl. Report SPRA605, pp. 1-23.
  24. C. Attaianese, and G. Tomasso, "Position measurement in industrial drives by means of low-cost resolver-to-digital converter," IEEE Trans. Instrum. Meas., vol. 56, no. 6, pp. 2155-2159, 2007. https://doi.org/10.1109/TIM.2007.908120
  25. S. Sarma, V. K. Agrawal, and S. Udupa, "Softwarebased resolver-to-digital conversion using a DSP," IEEE Trans. Ind. Electron., vol. 55, no. 1, pp. 371- 379, 2008. https://doi.org/10.1109/TIE.2007.903952
  26. Y. Zhu, J. M. Wang, and M. Zhu, "An approach based on AD converted resolver demodulation," in ICACTE 2010 - 2010 3rd International Conference on Advanced Computer Theory and Engineering, Proceedings, vol. 5, no. 1, pp. 192-195, 2010.
  27. Z. Ming, W. Jianming, D. Ling, Z. Yi, D. Ruzhen, and L. Yu, "A software based robust resolver-todigital conversion method in designed in frequency domain," in Proceedings - 2011 International Symposium on Computer Science and Society, ISCCS 2011, pp. 244-247, 2011.
  28. A. K. S. Baasch, E. C. Lemos, F. Stein, A. S. Paterno, J. De Oliveira, and A. Nied, "Resolver-to-digital conversion implementation - A filter approach to PMSM position measurement," in International Conference on Power Engineering, Energy and Electrical Drives, no. May 2011.
  29. S. C. M. Reddy, and K. N. Raju, "Inverse tangent based resolver to digital converter - a software approach," International Journal of Advances in Engineering & Technology, vol. 4, no. 2, pp. 228-235, 2012.