Revista Eletrônica de Potência (Brazilian Journal of Power Electronics)

Title: HYBRID DUAL-LOOP CONTROL FOR CURRENT REGULATION AND LOW-FREQUENCY RIPPLE REJECTION IN LED DRIVERS

Keywords: Current Ripple Reduction, Hybrid Control, LED Driver, LLC Resonant Converter

Abstract
This paper presents a new hybrid dual-loop control system for the DC/DC LLC resonant converter, operating as a downstream DC/DC converter in a two independent stage offline LED driver. The outer loop employs a PI controller to maintain the average LED current regulated at the reference value and reject parametric variation. The inner loop implements an adaptive periodic disturbance rejection (APDR) subsystem, thus conceiving the hybrid PI\&APDR controller. The APDR subsystem is designed to strictly reject the bus voltage ripple and limit its transmission to the LED current. Experimental results show the proposed controller feasibility in achieving good tracking behavior, reduced output current ripple under different bus voltage ripple amplitude and frequency, robustness against parametric variations, and simple implementation and design. For the sake of completeness, the proposed PI&APDR is compared with the conventional proportional resonant controller employing experimental results and extra analysis based on simulations.

[1] P. S. Almeida, D. Camponogara, M. A. D. Costa, J. M. Alonso, “Matching LED and Driver Life Spans: A Review of Different Techniques”, IEEE Industrial Electronics Magazine, vol. 9, no. 2, pp. 36–47, 2015.
Doi: 10.1109/MIE.2014.2352861

[2] C. Branas, F. J. Azcondo, J. M. Alonso, “Solid state lighting: A system review”, IEEE Industrial Electronics Magazine, vol. 7, no. 4, pp. 6–14, 2013.
Doi: 10.1109/MIE.2013.2280038

[3] IEEE Power Electronics Society, IEEE Std 1789 – Recommended Practices for Modulating Current in High-Brightness LEDs for Mitigating Health Risks to Viewers, 2015.
Doi: 10.1109/IEEESTD.2015.7118618

[4] M. Schratz, C. Gupta, T. J. Struhs, K. Gray, “A New Way to See the Light: Improving Light Quality with Cost-Effective LED Technology”, IEEE Industry Applications Magazine, vol. 22, no. 4, pp. 55–62, 2016.
Doi: 10.1109/MIAS.2015.2459089

[5] S. Li, S. C. Tan, C. K. Lee, E. Waffenschmidt, S. Y. Hui, C. K. Tse, “A Survey, Classification, and Critical Review of Light-Emitting Diode Drivers”, IEEE Transactions on Power Electronics, vol. 31, no. 2, pp. 1503–1516, 2016.
Doi: 10.1109/TPEL.2015.2417563

[6] Y. Wang, Y. Guan, J. Huang, W. Wang, D. Xu, “A Single-Stage LED Driver Based on Interleaved Buck-Boost Circuit and LLC Resonant Converter”, IEEE Journal of Emerging and Selected Topics in Power Electronics, vol. 3, no. 3, pp. 732–741, 2015.
Doi: 10.1109/JESTPE.2015.2421342

[7] Y. Wang, S. Gao, Y. Guan, J. Huang, D. Xu, W. Wang, “A Single-Stage LED Driver Based on Double LLC Resonant Tanks for Automobile Headlight With Digital Control”, IEEE Transactions on Transportation Electrification, vol. 2, no. 3, pp. 357–368, 2016.
Doi: 10.1109/TTE.2016.2571781

[8] J. Ma, X. Wei, L. Hu, J. Zhang, “LED driver based on boost circuit and LLC converter”, IEEE Access, vol. 6, pp. 49588–49600, 2018.
Doi: 10.1109/ACCESS.2018.2866502

[9] H. Ma, Y. Li, Q. Chen, L. Zhang, J. Xu, “A Single-Stage Integrated Boost-LLC AC-DC Converter with Quasi-Constant Bus Voltage for Multichannel LED Street-Lighting Applications”, IEEE Journal of Emerging and Selected Topics in Power Electronics, vol. 6, no. 3, pp. 1143–1153, 2018.
Doi: 10.1109/JESTPE.2018.2847327

[10] H. Dong, X. Xie, F. Mao, L. Zhang, Y. He, “A Novel Primary-Side Regulation Control Scheme for CCM and DCM LLC LED Driver Based on ’Magnetizing Current Cancellation Method’”, IEEE Transactions onPower Electronics, vol. 35, no. 11, pp. 12223–12237,
2020.
Doi: 10.1109/TPEL.2020.2989169

[11] H. Ma, W. Yu, C. Zheng, J. S. Lai, Q. Feng, B. Y. Chen, “A universal-input high-power-factor PFC pre-regulator without electrolytic capacitor for PWM dimming LED lighting application”, in IEEE Energy Conversion Congress and Exposition, 2011.
Doi: 10.1109/ECCE.2011.6064072

[12] G. M. Soares, J. M. Alonso, H. A. Braga, “Investigation of the Active Ripple Compensation Technique to Reduce Bulk Capacitance in Offline Flyback-Based LED Drivers”, IEEE Transactions on Power Electronics, vol. 33, no. 6, pp. 5206–5214,
2018.
Doi: 10.1109/TPEL.2017.2738779

[13] H. A. Ahn, S. K. Hong, O. K. Kwon, “A Highly Accurate Current LED Lamp Driver with Removal of Low-Frequency Flicker Using Average Current Control Method”, IEEE Transactions on Power Electronics, vol. 33, no. 10, pp. 8741–8753, 2017.
Doi: 10.1109/TPEL.2017.2783921

[14] M. F. Menke, A. R. Seidel, R. V. Tambara, “LLC LED Driver Small-Signal Modeling and Digital Control Design for Active Ripple Compensation”, IEEE Transactions on Industrial Electronics, vol. 66, no. 1, pp. 387–396, 2019.
Doi: 10.1109/TIE.2018.2829683

[15] C. Liu, J. Wang, K. Colombage, C. Gould, B. Sen, D. Stone, “Current Ripple Reduction in 4kW LLC Resonant Converter Based Battery Charger for Electric Vehicles”, in Energy Conversion Congress and Exposition (ECCE), pp. 6014–6021, 2015.
Doi: 10.1109/ECCE.2015.7310503

[16] Z. Zhang, Y. Q. Wu, D. J. Gu, Q. Chen, “Current Ripple Mechanism with Quantization in Digital LLC Converters for Battery Charging Applications”, IEEE Transactions on Power Electronics, vol. 33, no. 2, pp. 1303–1312, 2018.
Doi: 10.1109/TPEL.2017.2683798

[17] J. Jang, M. Joung, B. Choi, S. Hong, S. Lee, “Dynamic analysis and control design of optocoupler-isolated LLC series resonant converters with wide input and load variations”, IET Power Electronics, vol. 5, no. 6, pp. 755–764, 2012.
Doi: 10.1049/iet-pel.2011.0289

[18] S. K. Pidaparthy, J. Jang, B. Choi, “Push-pull mode digital control for LLC series resonant dc-to-dc converters”, IET Power Electronics, vol. 8, no. 6, pp. 6098–6113, 2015.
Doi: 10.1049/iet-pel.2014.0705

[19] Z. Fang, J. Wang, S. Duan, K. Liu, T. Cai, “Control of an LLC Resonant Converter Using Load Feedback Linearization”, IEEE Transactions on Power Electronics, vol. 33, no. 1, pp. 887–898, 2018.
Doi: 10.1109/TPEL.2017.2672731

[20] H. Ma, Q. Liu, J. Guo, “A Sliding-Mode Control Scheme for LLC Resonant DC/DC Converter with Fast Transient Response”, in IEEE Energy Conversion Congress and Exposition, pp. 161–166, 2012.
Doi: 10.1109/IECON.2012.6388814

[21] Z. Zhiyuan Hu, Y.-F. Yan-Fei Liu, P. C. Sen, “Bang-Bang Charge Control for LLC Resonant Converters”, IEEE Transactions on Power Electronics, vol. 30, no. 2, pp. 1093–1108, 2015.
Doi: 10.1109/TPEL.2014.2313130

[22] T. Nishimura, Y. Adachi, Y. Ohta, K. Higuchi, E. Takegami, “Robust Digital Control for an LLC Current- Resonant DC-DC
Converter”, in 9th International Conference on Electrical Engineering/Electronics, Computer, Telecommunications and Information Technology, pp. 1–4, 2012.
Doi: 10.1109/ECTICon.2012.6254168

[23] M. F. Menke, R. V. Tambara, Á. R. Seidel, “Model reference adaptive control in discrete-time applied on the LLC LED driver”, in Congresso Brasileiro de Automática CBA2018, João Pessoa, 2018.

[24] W. Feng, F. C. Lee, P. Mattavelli, “Optimal Trajectory Control of Burst Mode for LLC Resonant Converter”, IEEE Transactions on Power Electronics, vol. 28, no. 1, pp. 457–466, 2013.
Doi: 10.1109/TPEL.2012.2200110

[25] M. Bodson, Scott Douglas, “Adaptive algorithms for the rejection of sinusoidal disturbances with unknown frequency”, Automatica, vol. 22, no. 12, pp. 2213–2221, 1997.
Doi: 10.1016/S0005-1098(97)00149-0

[26] S. Pigg, M. Bodson, “Adaptive rejection of sinusoidal disturbances of known frequency acting on unknown systems”, Proceedings of the American Control Conference, vol. 2006, no. 2, pp. 4777–4781, 2006.
Doi: 10.1109/ACC.2006.1657476

[27] W. Kim, H. Kim, C. C. Chung, M. Tomizuka, “Adaptive output regulation for the rejection of a periodic disturbance with an unknown frequency”, IEEE Transactions on Control Systems Technology, vol. 19, no. 5, pp. 1296–1304, 2011.
Doi: 10.1109/TCST.2010.2066276

[28] R. Erickson, D. Maksimovic, Fundamentals of Power Electronics, 2nd ed., Springer, 2001.

[29] P. A. Ioannou, K. S. Tsakalis, “A robust direct adaptive controller”, IEEE Transactions on Automatic Control,
vol. 31, no. 11, pp. 1033–1043, 1986.
Doi: 10.1109/TAC.1986.1104168

[30] P. A. Ioannou, J. Sun, Robust Adaptive Control, 1st ed., Nov. 2012.

[31] H. Wu, Multi-Channel Constant Current (MC3) LED Driver for Indoor LED Luminaries, Master of science thesis, Faculty of the Virginia Polytechnic Institute, 2011.

[32] ENERGY STAR, “Program Requirements for Luminaires Partner Commitments – Version 2.2”, 2019.

[33] Bridgelux, “Bridgelux Vero 18 array series – Product Data Sheet DS32”, 2013.

[34] R. L. Lin, S. Y. Liu, C. C. Lee, Y. C. Chang, “Taylor series-expression-based equivalent circuit models of LED for analysis of LED driver system”, IEEE Transactions on Industry Applications, vol. 49, no. 4, pp. 1854–1862, 2013.
Doi: 10.1109/TIA.2013.2258313

[35] K. Ogata, Discrete-time control systems, 2nd ed., Prentice Hall, 1995.

[36] Texas Instruments, “Tiva TM4C1294NCPDT Microcontroller”, 2014.