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In this work, a new real-time Simulation method is designed for nonlinear control techniques applied to power converters. We propose two different implementations: in the first one (Single Hardware in The Loop: SHIL), both model and control laws are inserted in the same Digital Signal Processor (DSP), and in the second approach (Double Hardware in The Loop: DHIL), the equations are loaded in different embedded systems. With this methodology, linear and nonlinear control techniques can be designed and compared in a quick and cheap real-time realization of the proposed systems, ideal for both students and engineers who are interested in learning and validating converters performance. The methodology can be applied to buck, boost, buck-boost, flyback, SEPIC and 3-phase AC-DC boost converters showing that the new and high performance embedded systems can evaluate distinct nonlinear controllers. The approach is done using matlab-simulink over commodity Texas Instruments Digital Signal Processors (TI-DSPs). The main purpose is to demonstrate the feasibility of proposed real-time implementations without using expensive HIL systems such as Opal-RT and Typhoon-HL.

Abstract:In this paper, we propose adaptive nonlinear controllers for the Single-Ended Primary Inductance Converter (SEPIC). We also consider four distinct situations: AC-DC, DC-DC, Continuous Conduction Mode (CCM) and Discontinuous Conduction Mode (DCM). A comparative analysis between classic linear and nonlinear approaches to regulate the control loop is made. Three adaptive nonlinear control laws are designed: Feedback Linearization Control (FLC), Passivity-Based Control (PBC) and Interconnection and Damping Assignment Passivity-Based Control (IDAPBC). In order to compare the performance of these control techniques, numerical simulations were made in Software and Hardware in the Loop (HIL) for nominal conditions and operation disturbances. We recommend adaptive controllers for the two different situations: Adaptive Passivity-Based Feedback Linearization Control (APBFLC) for the PFC (Power Factor Correction) AC-DC system and IDAPBC-BB (IDAPBC Based on Boost converter) for the regulator DC-DC system.

Solid State Transformers (SST) are attracting considerable attention due to their great application potential in future smart grids. It is an essential technology capable of promoting the modernization of the electric power distribution system and it is considered a key element for interfacing future microgrid systems to medium voltage utility grids, allowing plug-and-play integration with multiple renewable energy sources, storage devices and DC power systems. Its main advantages in relation to conventional transformers are substantial reduction of volume and weight, fault isolation capability, voltage regulation, harmonic filtering, reactive power compensation and power factor correction. A three-stage modular cascaded topology has been considered as an adequate candidate for the SST implementation, consisting of multiple power modules with input series and output parallel connection. The modular structure presents many advantages, e.g., redundancy, flexibility, lower current harmonic content and voltage stress on the power switches, however component tolerances and mismatches between modules can lead to DC link voltage imbalance and unequal power sharing that can damage the solid state transformer. This paper proposes a decentralized strategy based on adaptive droop control capable of promoting voltage and power balance among modules of a modular cascaded SST, without relying on a communication network. The behavior of the proposed strategy is assessed through a MATLAB/Simulink simulation model of an 100 kVA SST and shows that power and voltage balance are attained through inner power distribution of the SST modules, being transparent to elements connected to the transformer input and output ports. Besides that, real-time simulation results are presented to validate the proposed control strategies. The performance of embedded algorithms is evaluated by the implementation of the SST in a real-time simulation hardware, using a Digital Signal Processor (DSP) and high level programming.

This paper presents a Hardware in the loop (HIL) simulation of a microcontroller using non-linear control implemented in PFC (Power Factor Correction) boost, buck and SEPIC converters. This is a non-conventional approach, where libraries are used to directly interface with the Texas's DSP 2812. Initially, the block diagrams that contain the control equations are constructed. Then, the codes are generated automatically. The advantages provided by the proposed method are: security, economy of development cycle time, easy understanding of the control process and programming, standardization and concurrent simulation. Three nonlinear control techniques -state feedback linearization (SFL), passivity based control (PBC) and interconnection and damping assignment passivity-based control (IDA-PBC) has been validated experimentally using HIL simulation for boost, buck and SEPIC converters. I. INTROD UCTIONIn literature it is possible to find many control approaches for power converters. The techniques range from the classic controller -PID controllers (proportional-integral-derivative) for the grid voltage and the current loop -shown in [1] and [2], recursive method as described by [3], passivity-based control [4], feedback linearization [5], among others. Whichever method, the use of the microcontroller is imperative. This device is programmed in a given language in order to perform functions, like adjusting the gains of the signals measured by the sensors and computing the control equations.In this paper, we present a Hardware in the loop simulation of a DSP (Digital Signal Processor) having as a case study, the non-linear control of a boost converter with power factor correction (PFC) and SEPIC converter. The advantages provided by the proposed method are: security, saving development time, facilitating the understanding of the process programming, standardization and concurrent simulation. The Hardware-in-the-Loop method (HIL) simulation is a technique that mixes elements both virtual and real elements. Currently this technique is often used to test embedded control systems, where both the hardware and system software are tested. Thus, the aim of this work is to implement a nonlinear dynamics simulation software converters studied for a system "Hardware in-the-Loop" (HIL), verifying the operation of the control and the system without the need for actual circuit. Next, details of the proposed methodology and theoretical background are presented. II. METHODOLOGYIn this work, the programming of the microcontroller has a different approach from conventional, once it is not necessary the development of lines of code. This is done straight from the 978-1-4 799-8779-5115/$3l.00 ©20 15 IEEE simulation blocks through code generating tools and software libraries. Figure I illustrates the steps of the proposed methodology. The first stage comprises the development of control laws of the system addressed. It is therefore a result of theoretical study and the system equations governing the control set, which may be by means of PID...

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