Stability and frequency regulation of inverters with capacitive inertia

In this paper, we address the problem of stability and frequency regulation of a recently proposed inverter. In this type of inverter, the DC-side capacitor emulates the inertia of a synchronous generator. First, we remodel the dynamics from the electrical power perspective. Second, using this model, we show that the system is stable if connected to a constant power load, and the frequency can be regulated by a suitable choice of the controller. Next, and as the main focus of this paper, we analyze the stability of a network of these inverters, and show that frequency regulation can be achieved by using an appropriate controller design. Finally, a numerical example is provided which illustrates the effectiveness of the method.

[1]  N. Jenkins,et al.  Comparison of the response of doubly fed and fixed-speed induction generator wind turbines to changes in network frequency , 2004, IEEE Transactions on Energy Conversion.

[2]  Florian Dorfler,et al.  Grid-Friendly Matching of Synchronous Machines by Tapping into the DC Storage* , 2016 .

[3]  T. L. Vandoorn,et al.  Analogy Between Conventional Grid Control and Islanded Microgrid Control Based on a Global DC-Link Voltage Droop , 2012, IEEE Transactions on Power Delivery.

[4]  Toshifumi Ise,et al.  Virtual synchronous generators: A survey and new perspectives , 2014 .

[5]  Nima Monshizadeh,et al.  Output Impedance Diffusion Into Lossy Power Lines , 2017, IEEE Transactions on Power Systems.

[6]  Ehab F. El-Saadany,et al.  Implementing Virtual Inertia in DFIG-Based Wind Power Generation , 2013, IEEE Transactions on Power Systems.

[7]  H.-P. Beck,et al.  Virtual synchronous machine , 2007, 2007 9th International Conference on Electrical Power Quality and Utilisation.

[8]  M. C. Chandorkar,et al.  Improvement of Transient Response in Microgrids Using Virtual Inertia , 2013, IEEE Transactions on Power Delivery.

[9]  K. Visscher,et al.  Grid tied converter with virtual kinetic storage , 2009, 2009 IEEE Bucharest PowerTech.

[10]  B Renders,et al.  A Control Strategy for Islanded Microgrids With DC-Link Voltage Control , 2011, IEEE Transactions on Power Delivery.

[11]  Francesco Bullo,et al.  Breaking the Hierarchy: Distributed Control and Economic Optimality in Microgrids , 2014, IEEE Transactions on Control of Network Systems.

[12]  Jun Zhou,et al.  Improved Swing Equation and Its Properties in Synchronous Generators , 2009, IEEE Transactions on Circuits and Systems I: Regular Papers.

[13]  Arjan van der Schaft,et al.  Nonlinear analysis of an improved swing equation , 2016, 2016 IEEE 55th Conference on Decision and Control (CDC).

[14]  Goran Andersson,et al.  Impact of Low Rotational Inertia on Power System Stability and Operation , 2013, 1312.6435.

[15]  Pieter Tielens,et al.  The relevance of inertia in power systems , 2016 .

[16]  Achim Woyte,et al.  Virtual synchronous generator: An element of future grids , 2010, 2010 IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT Europe).

[17]  Karl Henrik Johansson,et al.  Distributed PI-control with applications to power systems frequency control , 2014, 2014 American Control Conference.

[18]  Saad Mekhilef,et al.  Inertia response and frequency control techniques for renewable energy sources: A review , 2017 .

[19]  L. Bregman The relaxation method of finding the common point of convex sets and its application to the solution of problems in convex programming , 1967 .

[20]  Alessandro Astolfi,et al.  Conditions for stability of droop-controlled inverter-based microgrids , 2014, Autom..

[21]  Frequency Stability Evaluation Criteria for the Synchronous Zone of Continental Europe – Requirements and impacting factors – , 2016 .

[22]  Qing-Chang Zhong,et al.  Synchronverters: Inverters That Mimic Synchronous Generators , 2011, IEEE Transactions on Industrial Electronics.

[23]  Jan Pierik,et al.  Inertial response of variable speed wind turbines , 2006 .

[24]  Claudio De Persis,et al.  An internal model approach to (optimal) frequency regulation in power grids with time-varying voltages , 2014, Autom..

[25]  Romeo Ortega,et al.  Passivity of Nonlinear Incremental Systems: Application to PI Stabilization of Nonlinear RLC Circuits , 2006, Proceedings of the 45th IEEE Conference on Decision and Control.

[26]  Yushi Miura,et al.  Oscillation Damping of a Distributed Generator Using a Virtual Synchronous Generator , 2014, IEEE Transactions on Power Delivery.

[27]  Claudio De Persis,et al.  Agreeing in networks: Unmatched disturbances, algebraic constraints and optimality , 2017, Autom..

[28]  A.R. Bergen,et al.  A Structure Preserving Model for Power System Stability Analysis , 1981, IEEE Transactions on Power Apparatus and Systems.

[29]  Pravin Varaiya,et al.  A structure preserving energy function for power system transient stability analysis , 1985 .

[30]  Johannes Schiffer,et al.  A Lyapunov approach to control of microgrids with a network-preserved differential-algebraic model , 2016, 2016 IEEE 55th Conference on Decision and Control (CDC).

[31]  ZhouJun,et al.  Improved swing equation and its properties in synchronous generators , 2009 .

[32]  Francesco Bullo,et al.  Synchronization and power sharing for droop-controlled inverters in islanded microgrids , 2012, Autom..

[33]  Nima Monshizadeh,et al.  Bregman Storage Functions for Microgrid Control , 2015, IEEE Transactions on Automatic Control.

[34]  Yushi Miura,et al.  Power System Stabilization Using Virtual Synchronous Generator With Alternating Moment of Inertia , 2015, IEEE Journal of Emerging and Selected Topics in Power Electronics.