Using co-design techniques to increase the reliability of the Electronic control System for a Multilevel Power Converter Javier C. Brook, Francisco J. Rodríguez, Pedro Martín, Emilio J. Bueno Department of Electronics. University of Alcalá (Spain) IECON 2006 University of AlcaláDepartment of Electronics Researching group in Electronic Engineering applied to the Renewable Energies

Contents 1.Introduction 2.Objectives 3.Overview of the Processing System 4.Proposals to apply co-design techniques 5.Experimental results 6.Conclusions Department of Electronics IECON 2006 Researching group in Electronic Engineering applied to the Renewable Energies University of Alcalá

Contents 1.Introduction 2.Objectives 3.Overview of the Processing System 4.Proposals to apply co-design techniques 5.Experimental results 6.Conclusions Department of Electronics IECON 2006 Researching group in Electronic Engineering applied to the Renewable Energies University of Alcalá

Introduction: System to control Department of Electronics IECON 2006 Researching group in Electronic Engineering applied to the Renewable Energies University of Alcalá Grid U base (Base voltage)480V ω base (Base frequency)2π50rad/s Converter S n (Nominal Power)150kVA I base (Base current)312,5A

Introduction: Control Electronic System Department of Electronics IECON 2006 Researching group in Electronic Engineering applied to the Renewable Energies University of Alcalá

Contents 1.Introduction 2.Objectives 3.Overview of the Processing System 4.Proposals to apply co-design techniques 5.Experimental results 6.Conclusions Department of Electronics IECON 2006 Researching group in Electronic Engineering applied to the Renewable Energies University of Alcalá

Objectives The main objective is to increase the reliability of the electronic control system, applying codesign techniques. This objective will be achieve by means of several partial objectives: –Hardware and software reliability modelling –New codesign algorithms, that take into account time, area, power and reliability restrictions Department of Electronics IECON 2006 University of Alcalá Researching group in Electronic Engineering applied to the Renewable Energies

Contents 1.Introduction 2.Objectives 3.Overview of the Processing System 4.Proposals to apply co-design techniques 5.Experimental results 6.Conclusions Department of Electronics IECON 2006 Researching group in Electronic Engineering applied to the Renewable Energies University of Alcalá

Block diagram of the Control Electronic System Department of Electronics IECON 2006 University of Alcalá Researching group in Electronic Engineering applied to the Renewable Energies DSP Data acquisition A/D conversion FPGA Adaptation of analog signals Analog signals System references Driving of IGBTs Faults of IGBT drivers Driving of relays Optical transmitters Optical receivers Relays To IGBT drivers To control the converter breakers FPGA-DSP Interface 12 bits Processor Module Coprocessor Module Computational Module TMS320C6713 SPARTAN II MAX1309 Ts=200μs

Analysis of the tasks executed by the “Computational Module” Department of Electronics IECON 2006 University of Alcalá Researching group in Electronic Engineering applied to the Renewable Energies TasksTSTS T run Operation typeAlgorithm type Selected Device For the line-side converter Current vector controller200μs <200μs Trigonometric and matrix Control DSP Identification of different disturbances200μs FPGA DSC (Delay Signal Cancellation) [17]200μsFPGA SPLL [17]200μs Arithmetic DSP DC-bus voltage controller200μs Arithmetic DSP For the generator-side converter Vector controller.200μs <200μs Trigonometric and matrix Control DSP Turbine controller. Tracking of the maximum power point. 200μs ArithmeticDSP For the two converters PWM generation (carrier frequency 2.5KHz and 24 signals) 200μsArithmeticParallelFPGA Encoder reading200μs ArithmeticParallelFPGA Acquisition data200μs -ParallelFPGA

DSP Programming Department of Electronics IECON 2006 University of Alcalá Researching group in Electronic Engineering applied to the Renewable Energies

FPGA Programming Department of Electronics IECON 2006 University of Alcalá Researching group in Electronic Engineering applied to the Renewable Energies

Timing events in the DSP and FPGA Department of Electronics IECON 2006 University of Alcalá Researching group in Electronic Engineering applied to the Renewable Energies

Contents 1.Introduction 2.Objectives 3.Overview of the Processing System 4.Proposals to apply co-design techniques 5.Experimental results 6.Conclusions Department of Electronics IECON 2006 Researching group in Electronic Engineering applied to the Renewable Energies University of Alcalá

Reliability calculation Reliability definition: –Is the probability that a component will perform its intended function satisfactorily for a period of time [t 0,t], given that the component was working properly at time t 0 Department of Electronics IECON 2006 University of Alcalá Researching group in Electronic Engineering applied to the Renewable Energies

Reliability calculation Hardware reliability: –Error in semiconductor devices: soft errors. Due to external radiations, impurities in the devices, etc. –Evaluation of soft errors [Tosun, et al. 05][Alexandrescu, et al. 02] Simulation. Fault injection. –As the result of this evaluation, it can be obtained a table with the reliability of some basic elements: adder, multiplier, etc. Department of Electronics IECON 2006 University of Alcalá Researching group in Electronic Engineering applied to the Renewable Energies

Reliability calculation Hardware reliability: –Reliability of some basic device implemented in FPGA [Tosun, et al. 05][Alexandrescu, et al. 02] Department of Electronics IECON 2006 University of Alcalá Researching group in Electronic Engineering applied to the Renewable Energies

Reliability calculation Software reliability: –Definition: The probability of failure-free software operation for a specified period of time in a specified environment. –To model and predict software reliability, a SRGM (software reliability growth model) can be used. Department of Electronics IECON 2006 University of Alcalá Researching group in Electronic Engineering applied to the Renewable Energies

Reliability calculation Appling hardware and software reliability models and estimation algorithms, the following table (technology library) can be obtained for the digital control system tasks: Department of Electronics IECON 2006 University of Alcalá Researching group in Electronic Engineering applied to the Renewable Energies A. Acquisition data. B. PWM generation (carrier frequency 2 2.5KHz and 24signals) C. Identification of different disturbances D. SPLL. E. DSC (Delay Signal Cancellation) F. DC-bus voltage controller. G. Current vectorial controller. H. Vectorial controller. I. Turbine controller. Tracking of the mnmaximum power point. J. Encoders reading.

Codesign algorithm In order to increase the overall digital control system reliability, we use a partition algorithm that take into account several parameters: –Reliability, time processing, delay and area. Our co-design methodology consists of the following steps: –Obtaining an initial solution by allocating the most reliable elements from the technology library to each task. –To make adjustments to fulfill the specification delay, the specification area and other design requirements. –To apply Engineering Software Reliability to the tasks implemented in DSP. Department of Electronics IECON 2006 University of Alcalá Researching group in Electronic Engineering applied to the Renewable Energies

Contents 1.Introduction 2.Objectives 3.Overview of the Processing System 4.Proposals to apply co-design techniques 5.Experimental results 6.Conclusions Department of Electronics IECON 2006 Researching group in Electronic Engineering applied to the Renewable Energies University of Alcalá

Experimental Setup Department of Electronics DIGILAB 2E Link Board Interface Board TMS320C6713 DSK Optical transmitters Optical receivers ADCs Relays Digital Signal Processing Acquisition card Glue logic IECON 2006 University of Alcalá Researching group in Electronic Engineering applied to the Renewable Energies

DSP execution Department of Electronics IECON 2006 University of Alcalá Researching group in Electronic Engineering applied to the Renewable Energies TSTS Control algorithm execution k-1kk+1k+2 Number of cycles Execution graph

Task distribution Applying the codesign algorithm, the task distribution is: Department of Electronics IECON 2006 University of Alcalá Researching group in Electronic Engineering applied to the Renewable Energies

Contents 1.Introduction 2.Objectives 3.Overview of the Processing System 4.Proposals to apply co-design techniques 5.Experimental results 6.Conclusions Department of Electronics IECON 2006 Researching group in Electronic Engineering applied to the Renewable Energies University of Alcalá

Conclusions A co-design algorithm has been presented, based on applying the metric reliability of hardware and software, in order to improve the performance of a processing system that uses FPGA and DSP. Future works: –Accurate evaluation of hardware and software reliability. –New co-design algorithms (partitioning task between other processing units) Department of Electronics IECON 2006 University of Alcalá Researching group in Electronic Engineering applied to the Renewable Energies

Using co-design techniques to increase the reliability of the Electronic control System for a Multilevel Power Converter Javier C. Brook, Francisco J. Rodríguez, Pedro Martín, Emilio J. Bueno Department of Electronics. University of Alcalá (Spain) IECON 2006 University of AlcaláDepartment of Electronics Researching group in Electronic Engineering applied to the Renewable Energies ACKNOWLEDGMENTS This work has been financied by the Spanish administration (ENE C04-01)