FPGA design methodology for industrial control systems—a review

This paper reviews the state of the art of fieldprogrammable gate array (FPGA) design methodologies with a focus on industrial control system applications. This paper starts with an overview of FPGA technology development, followed by a presentation of design methodologies, development tools and relevant CAD environments, including the use of portable hardware description languages and system level programming/design tools. They enable a holistic functional approach with the major advantage of setting up a unique modeling and evaluation environment for complete industrial electronics systems. Three main design rules are then presented. These are algorithm refinement, modularity, and systematic search for the best compromise between the control performance and the architectural constraints. An overview of contributions and limits of FPGAs is also given, followed by a short survey of FPGA-based intelligent controllers for modern industrial systems. Finally, two complete and timely case studies are presented to illustrate the benefits of an FPGA implementation when using the proposed system modeling and design methodology. These consist of the direct torque control for induction motor drives and the control of a diesel-driven synchronous stand-alone generator with the help of fuzzy logic

An improved FPGA implementation of direct torque control for induction machines

This paper presents a novel direct torque control (DTC) approach for induction machines, based on an improved torque and stator flux estimator and its implementation using Field Programmable Gate Arrays (FPGA). The DTC performance is significantly improved by the use of FPGA, which can execute the DTC algorithm at higher sampling frequency. This leads to the reduction of the torque ripple and improved flux and torque estimations. The main achievements are: i) calculating a discrete integration operation of stator flux using backward Euler approach, ii) modifying a so called non-restoring method in calculating the complicated square root operation in stator flux estimator, iii) introducing a new flux sector determination method, iv) increasing the sampling frequency to 200kHz such that the digital computation will perform similar to that of the analog operation, and v) using two’s complement fixed-point format approach to minimize calculation errors and the hardware resource usage in all operations. The design was achieved in VHDL, based on a Matlab/Simulink simulation model. The Hardware-In-the-Loop (HIL) method is used to verify the functionality of the FPGA estimator. The simulation results are validated experimentally. Thus, it is demonstrated that FPGA implementation of DTC drives can achieve excellent performance at high sampling frequency

A Simplified Speed Control of Induction Motor based on a Low Cost FPGA

This paper investigates the development of a simplified speed control of induction motor based on indirect field oriented control (FOC). An original PI-P controller is designed to obtain good performances for speed tracking. Controller coefficients are carried out with analytic approach. The algorithm is implemented using a low cost Field Programmable Gate Array (FPGA). The implementation is followed by an efficient design methodology that offers considerable design advantages. The main advantage is the design of reusable and reconfigurable hardware modules for the control of electrical systems. Experimental results carried on a prototyping platform are given to illustrate the efficiency and the benefits of the proposed approach

Implementation and verification of a hardware-basedcontroller for a three-phase induction motor on an FPGA

L’objectiu d’aquesta tesi és estudiar diverses tècniques de control motor per tal d’implementar i verificar un controlador basat en hardware per a un motor d’inducció trifàsic desenvolupat en llenguatge VHDL i funcionant en una FPGA Artix-7 (Xil-inx). Aquest controlador està basat en tècniques de variació de freqüència. Els mòduls que defineixen la descripció de hardware funcionen simultàniament entre ells, i permeten agilitzar el sistema, millorant el rendiment i la resposta del motor, en comparació amb un microcontrolador. Aquesta tesi està relacionada amb els sistemes digitals, l’electrònica de potència i els sistemes de control.Outgoin

FPGA Based Powertrain Control for Electric Vehicles

In this article an FPGA based solution for the advance control of multi-motor EVs was proposed. The design was build around a powertrain IP Core library containing the most relevant functions for the EV operation: motor torque and flux regulation, energy loss minimization and vehicle safety. Due to the parallel, modularity and reconfigurability features of FPGAs, this library can be reused in the development of several control architectures that best suits the EV powertrain configuration (single or multi-motor) and functional requirements. As proof of concept, the powertrain library was employed in the design of minimal control system for a bi-motor EV prototype and implemented in a low cost Xilinx Spartan 3 FPGA. Experimental verification of the control unit was provided, showing reasonable consumption metrics and illustrating the energy benefits from regenerative braking

DTC-FPGA Drive for Induction Motors

Direct torque control, or DTC, is an electrical motor strategy characterized for simplicity and high performance when controlling industrial machines such as induction motors. However, this technique is often accompanied by an unwanted deformation on the torque and flux signals denominated ripple, which can cause audible noise and vibration on the motor. Considerable research has been presented on this topic; nevertheless the original DTC algorithm is often modified to the point that it is as complex as other motor control strategies. To solve this problem, a novel architecture was designed in order to reduce the sampling period to a point where torque ripple is minimal, while maintaining the classical DTC control structure. In this work, the original DTC control strategy was implemented on a Virtex-5 field programmable gate array (FPGA). For the code, a two´s complement fixed-point format and a variable word-size approach was followed using very-high-speed integrated circuit hardware description language (VHDL). Results were validated using MATLAB/Simulink simulations and experimental tests on an induction motor. With this new architecture, the authors hope to provide guidelines and insights for future research on DTC drives for induction motors

An Improved FPGA Implementation of Direct Torque Control for Induction Machines

This paper presents a novel direct torque control (DTC) approach for induction machines, based on an improved torque and stator flux estimator and its implementation using field-programmable gate arrays (FPGA). The DTC performance is significantly improved by the use of FPGA, which can execute the DTC algorithm at higher sampling frequency. This leads to the reduction of the torque ripple and improved flux and torque estimations. The main achievements are: 1) calculating a discrete integration operation of stator flux using backward Euler approach; 2) modifying a so called nonrestoring method in calculating the complicated square root operation in stator flux estimator; 3) introducing a new flux sector determination method; 4) increasing the sampling frequency to 200 kHz such that the digital computation will perform similar to that of the analog operation; and 5) using two’s complement fixed-point format approach to minimize calculation errors and the hardware resource usage in all operations. The design was achieved in VHDL, based on a MATLAB/Simulink simulation model. The Hardware-in-the-Loop method is used to verify the functionality of the FPGA estimator. The simulation results are validated experimentally. Thus, it is demonstrated that FPGA implementation of DTC drives can achieve excellent performance at high sampling frequency

Rapid Control Prototyping Platform for the Design of Control Systems for Automotive Electromechanical Actuators

This article introduces and discusses the development of a low-cost Rapid Control Prototyping Platform (RCPP). The aim of RCPP is to automate design of control algorithm of electromechanical actuators and simultaneous implementation it into a target microprocessor. The RCPP is stand-alone system containing software tools and electronic hardware in order to provide all development steps from system identification, model-based control design and code generation up to hardware implementation. The system can be used for development of a torque, speed or position controller for low power electromechanical actuators especially in the area of automotive application. The hardware of the platform is based on a 16-bit microcontroller and includes essential power semiconductor switches, sensors and communication interfaces. The presented RCPP system supports Real-Time-Work interface of MATLAB/Simulink and Calibration Protocol for CAN-Bus communication