Optimizing of sampling in a low-cost single-phase instantaneous AC-grid synchronization unit with discrete calculation of derivative function

This paper deals with single-phase grid synchronization unit suitable for integration in interface converters of distributed renewable energy sources. A well known problem of the second orthogonal component for Park transformation of a phase-locked loop is successfully solved with a help of the approximate derivative function for the first time. Optimal sampling times for finding this derivative function are calculated with highest accuracy. It is shown that the implementation of approximate derivative function can reduce start-up time of the synchronization unit. The method is implemented in a low-cost microcontroller and successfully experimentally verified with a physical model of the grid, as well as with a real voltage sensor.

[1]  Remus Teodorescu,et al.  A New Single-Phase PLL Structure Based on Second Order Generalized Integrator , 2006 .

[2]  Se-Kyo Chung,et al.  A phase tracking system for three phase utility interface inverters , 2000 .

[3]  Hui Li,et al.  DC Offset Error Compensation for Synchronous Reference Frame PLL in Single-Phase Grid-Connected Converters , 2012, IEEE Transactions on Power Electronics.

[4]  Ilhami Colak,et al.  Design and application of a novel zero-crossing detector circuit , 2011, 2011 International Conference on Power Engineering, Energy and Electrical Drives.

[5]  H. Farhangi,et al.  The path of the smart grid , 2010, IEEE Power and Energy Magazine.

[6]  Hae-Seung Lee,et al.  Zero-crossing detector based reconfigurable analog system , 2010, 2010 IEEE Asian Solid-State Circuits Conference.

[7]  Aleksandar Radonjic,et al.  Stochastic Measurement of Power Grid Frequency Using a Two-Bit A/D Converter , 2014, IEEE Transactions on Instrumentation and Measurement.

[8]  Leonids Ribickis,et al.  A PLL Scheme for Synchronization with Grid Voltage Phasor in Active Power Filter Systems , 2010 .

[9]  Álvaro Hernández,et al.  A DSP- and FPGA-Based Industrial Control With High-Speed Communication Interfaces for Grid Converters Applied to Distributed Power Generation Systems , 2009, IEEE Transactions on Industrial Electronics.

[10]  Seppo J. Ovaska,et al.  Noise reduction in zero crossing detection by predictive digital filtering , 1995, IEEE Trans. Ind. Electron..

[11]  J. Van den Keybus,et al.  Design and Operation of a Phase-Locked Loop with Kalman Estimator-Based Filter for Single-Phase Applications , 2006, IECON 2006 - 32nd Annual Conference on IEEE Industrial Electronics.

[12]  Biswajit Basu,et al.  Predictive zero-crossing detection algorithm by time localised iterative least-square technique , 2011, Proceedings of the 2011 14th European Conference on Power Electronics and Applications.

[13]  S. Valiviita.  Neural network for zero-crossing detection of distorted line voltages in weak AC-systems , 1998, IMTC/98 Conference Proceedings. IEEE Instrumentation and Measurement Technology Conference. Where Instrumentation is Going (Cat. No.98CH36222).

[14]  Seppo J. Ovaska,et al.  Digital Filtering for Robust 50/ Zero-Cros sing Detectors , 1996 .

[15]  N. Matsui,et al.  A control strategy of single-phase active filter using a novel d-q transformation , 2003, 38th IAS Annual Meeting on Conference Record of the Industry Applications Conference, 2003..

[16]  Marek Mägi.  Utilization of Electric Vehicles Connected to Distribution Substations for Peak Shaving of Utility Network Loads , 2013 .

[17]  Bo Wen,et al.  Anti-islanding protection in three-phase converters using grid synchronization small-signal stability , 2012, 2012 IEEE Energy Conversion Congress and Exposition (ECCE).

[18]  C Picardi,et al.  A simple and low-cost PLL structure for single-phase grid-connected inverters , 2010, SPEEDAM 2010.

[19]  Yan-Ru Zhong,et al.  A digital PLL control method based on the FIR filter for a grid-connected single-phase power conversion system , 2008, 2008 IEEE International Conference on Industrial Technology.

[20]  R. Wall.  Simple methods for detecting zero crossing , 2003, IECON'03. 29th Annual Conference of the IEEE Industrial Electronics Society (IEEE Cat. No.03CH37468).

[21]  Kristaps Vitols,et al.  Low-Cost Voltage Zero-Crossing Detector for AC-Grid Applications , 2014 .

[22]  Ilya Galkin,et al.  Implementation of single-phase grid synchronization module with low-end microcontrollers , 2014, 2014 55th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON).