Hardware-in-the-loop Simulation Research Articles

Load Control for the DC Electrical Power Distribution System of the More Electric Aircraft

The more electric aircraft concept aims at increasing the amount and the power of the electrical subsystems on the next generation of aircraft. One of the major challenges in this framework is that the electric power is generated by means of electrical generators connected to the jet turbine shaft. In order to satisfy the peak power demand and overload conditions, the generators are oversized, increasing weight and total cost of operation. Possible solutions to this problem is to decrease the size of the generator and to provide the peak power with storage systems. As an alternative, load disconnection during peak demand (load-shedding) can be enforced with solid-state switches. This paper presents a different approach, i.e., by modifying the dc voltage of the distribution, the load can be controlled. In order to achieve this objective, a precise on-line identification algorithm is proposed. Theoretical analysis is performed, and simulation results on a study-case distribution system are reported, highlighting how the proposed load identification and control method effectively manages a power curtailment condition without load-shedding or storage systems. Power hardware in the loop simulations on a dc microgrid with a multiport power converter confirm the simulation analysis.

Research on the control strategy of distributed electric vehicle based on xpc test platform

In this paper, the distributed hybrid electric vehicle is taken as the research object. A drive control strategy is proposed based on the optimal working curve control strategy of the engine, and taking full consideration of the battery SOC working range and boundary speed threshold. The strategy model was generated xPC Target executable program by MATLAB/RTW toolbox and it was downloaded to the target machine to be run in real-time. The vehicle controller access the xPC real-time simulation testing system, which have simulation analysis on the condition of 0-32km/h acceleration. The test results demonstrate that the hardware in the loop simulation of xPC structure is feasible, and the real-time simulation testing system is reliable, meanwhile the rationality of the driving control strategy on this platform is verified.

A Wheel Slip Control Approach Integrated With Electronic Stability Control for Decentralized Drive Electric Vehicles

Wheel slip control, as a basis for vehicle stability control, prevents loss of traction. A new wheel slip control approach that does not require chassis velocity is proposed in this paper. The proposed approach uses the wheel speeds and the chassis acceleration measured on the acceleration sensor to estimate the maximum tire-road friction. Then, the motor torque is constrained using the maximum tire-road friction. To ensure the vehicle starts smoothly and to enhance its acceleration performance, a fuzzy controller is used to determine whether the output torque should be constrained. The main advantage of this approach is that it is indifferent to the vehicle mass and driving resistance. Hardware-in-the-loop (HIL) simulation results validated that the proposed approach could improve the vehicle stability when the vehicle corners on slippery conditions, which is attributable to the approach's robustness to vehicle mass and driving resistance. Moreover, HIL simulation proved that it was feasible to implement the proposed approach in real vehicles.

Design of Power Hardware-in-the-Loop Simulations for Integrated Starter–Generator Systems

The integrated starter–generator system (ISGS) is a combination of starter and generator for independent power systems in transportation. It replaces both a conventional starter and generator with a single set of highly integrated devices. A power hardware in the loop simulation that is flexible and can include the hardware under test is used to test the ISGS under representative field conditions. This paper utilizes the special structure of the ISGS and proposes an ISGS emulator (ISGSE) to develop and test the converter. The proposed ISGSE can be used to test a variety of motor drives or rectifiers including dynamic capabilities without necessitating a connection to a large motor load. To emulate the ISGS, the structure and operation principle in different modes are introduced in detail. Also, the issue of stability and accuracy is discussed in this paper. Detailed simulation and experimental comparisons are carried out between the ISGS and the ISGSE, which validates the proposed ISGSE as an effective tool for designing and testing new motor drives.

Power System Real-Time Emulation: A Practical Virtual Instrumentation to Complete Electric Power System Modeling

Hardware-in-the-loop (HIL) simulation is a technique that is being used increasingly in the development and test of complex systems. Real-world testing of an intricate system in a field-like power plant can be challenging, time-consuming, expensive, and hazardous. HIL emulators allow engineers to test devices thoroughly and efficiently in a virtual environment with high reliability and minimum risk of defect. In this paper, the complete electric power system (including generator, turbine-governor, excitation system, transmission lines, transformer, external grid and related loads) is implemented in a MATLAB/Simulink environment. Different virtual instrument pages are modeled in the graphical programming language of LabVIEW which enable fast and reliable measurement functions such as data acquisition, archiving, real-time graphical display and processing. The interaction between MATLAB and LabVIEW is accomplished by generating a Pharlap ETS Targets *.dll file which enables the two software to exchange real-time data. Also, a real 1518-kW excitation system is considered as a test case for the introduced HIL system. This equipment is connected to LabVIEW software through a National Instrument PXI technology. Different scenarios (electrical frequency/active power change, voltage step response, etc.) are simulated in the designed power system emulator (PSE). The validity of the implemented model for the excitation system is verified by finding good matching between MATLAB and HIL simulation results.

Hardware-in-the-Loop Simulation for Active Control of Tramcars With Independently Rotating Wheels

The wheelset is an important part that affects the dynamics of railway vehicles. The main purpose of the wheelset is to solve the problem of stability, curve performance, comfort, and wear. A conventional railway vehicle adopts rigid-axle wheelset (RW) due to the self-centering mechanism. On the other hand, independently rotating wheels (IRWs) have not been widely applied in the railway industry, since they do not generate any self-centering mechanism. It creates excessive wear, and derailment may occur. However, the IRWs have excellent curving performance compared with the RWs, and it enables realizing a low-floor structure that is convenient for passengers to get on and off. The recent active control technology has made it possible to generate a centering force in the IRWs. There are still many obstacles for the practical use of this technology, and it is necessary to verify the control strategies through various test methods. In this paper, an analytical model is derived, and an active control strategy is studied. To verify the validity of the active control strategy, a novel hardware-in-the-loop simulation (HILS) configuration using a real-time model and a motor-generator set are proposed.

Hardware in the Loop Simulation for Model Predictive Control Applied to Satellite Attitude Control

Space systems are extremely complex and expensive robotic devices used in scientific, military and communication applications. Attitude control for aerospace systems is responsible for ensuring that the space object is in position, velocity and correct trajectories, stabilizing the spacecraft and guiding in the desired directions during the mission, regardless of external disturbances. Therefore, control systems design must satisfy the satellite’s operating requirements and deal with several physical constraints to guarantee safety and performance. In this paper, a parameterized Model Predictive Control (MPC) for attitude control of an artificial satellite is developed. The main feature of the proposed control scheme consists of obtaining an optimal solution at each sampling instant respecting structurally satellite operational constraints ensuring stability, tracking performance and operational reliability, which is a crucial point for aerospace missions. To address real-time operational conditions, Hardware-in-the-loop (HIL) technique was developed to test and validate an embedded MPC strategy under realistic implementation conditions.

An Improved Voltage Controller for Distribution Static Compensator

Distribution System consist of different types of loads like linear and nonlinear load. Due to different types of loads, voltage unbalance and other power quality related issues will occur. To overcome this problem, a voltage source inverter based device called distribution static compensator can be used. In this work, an improved voltage controller for distributed static compensator, based on power balancing theory is presented. The improved controller uses only voltage sensors and this controller is developed by considering unbalanced load conditions. Proportional Integral controller is used for maintaining terminal voltage and DC link voltage. The controller is verified for different voltage disturbances such as sag and swell. MATLAB/SIMULINK package is used to verify the controller using simulation. The controller is also verified using Hardware in the loop simulation using DSPACE and results are presented for different voltage disturbances.

Hardware in the loop simulation for homing missiles

In this paper, we present a new method of testing the guidance, navigation and control (GNC) system of missiles with homing guidance based on image processing homing head. Testing of the GNC system of the homing missile is usually carried out on a five axis or three axis motion simulator in the hardware in the loop (HWIL) environment. HWIL testing on a five axis motion simulator is applicable to all guidance systems regardless of the type of detector used in the homing head, but equipping the laboratory is at least two times more expensive compared to the new method of testing presented here. The goal of this paper is to present a relatively cheap, simple and effective way of testing the guidance systems in cases when the type of detector used in the homing head is either television (TV) or Infra-Red (IR) camera, more precisely when image processing homing heads are used.

Analysis and Design of DC-Bus Voltage Controller of Energy Storage Systems in DC Microgrids

In this paper, a novel voltage controller of energy storage system (ESS) in DC microgrids (DC-MG) is proposed to enhance the DC-bus voltage stability. At first, a mathematical model of the DC-MG is developed in a state-space form. Then, the voltage controller of the ESS is designed by using the methodology of the IDA-PBC (interconnection and damping assignment-passivity-based control) with an integral action. System stability has been analyzed with passivity-based stability criterion (PBSC). The proposed controller gives the robust performance to the parameters variation. The validity of the proposed control scheme has been verified by the hardware-in-the-loop simulation (HILS) results.

Raspberry Pi-based HIL simulators for control education

Abstract Excluding hands-on experience with physical plants from control education is tempting in many aspects, but at the same time it is very dangerous. This paper explains why and recommends a compromise between demanding maintenance of physical plants for students to control and relying on pure numeric simulations within the whole curriculum. The golden mean might be the use of real-time simulators with physical inputs and outputs, i.e. hardware-in-the-loop (HIL) simulators. Three examples of HIL simulators are presented, covering a coupled tanks model, a quarter-car model and a nuclear reactor model.

Hardware-in-the-Loop Simulation for a Multiaxial Suspension Test Rig with a Nonlinear Spatial Vehicle Dynamics Model

Hardware-in-the-Loop (HiL) simulations where a mechatronic system is used as the device under test (DUT), are established in the automotive sector for the design of active suspension components, e.g. roll-stabilizers. Usually, uniaxial actuator systems within the test rig are applied for the excitation of the DUT. However, in the context of mechatronic suspension systems incorporating multiple mechatronic subsystems, more sophisticated HiL test rigs / simulations with multiaxial excitation of the DUT are necessary. This contribution presents the model-based design of a HiL simulation for a multiaxial vehicle axle test rig. Within the HiL simulation a nonlinear spatial vehicle dynamics model with 36 states is used to reproduce the environment of the DUT in real-time. The implemented model and its requirements are described in detail. An appropriate HiL control framework is developed, which combines the vehicle dynamics model with the hybrid motion/force control of the manipulator systems. The primary actuator is a hydraulic hexapod. Simulation results and measurements obtained with the HiL system show the effectiveness of this approach. The potential for chassis control validation and design is highlighted in comparison to a highly detailed benchmark vehicle dynamics model.

Low-Cost Hardware-in-the-Loop Platform for Embedded Control Strategies Simulation

The increasing need for testing and prototyping designs under more realistic conditions is responsible for the advancement of new types of simulation. In this scenario, one type of simulation which has gained high notoriety and applicability is the one known as Hardware-in-the-Loop (HIL). This technique allows real and virtual components of a system to be tested together, making it possible to perform tests under realistic (and even extreme) conditions without harming the real system or a prototype built only for testing. The objective of this work was to develop a low-cost HIL simulation platform to be used for many different applications, unlike most commercial ones, that are developed for one exclusive field of application, such as automotive, aerospace, power electronics, among others. Thus, the main contribution of this work is the project of a HIL platform capable of simulating different types of systems, making it possible to validate embedded control strategies designed for them. Two different applications are tested in order to validate the HIL platform: an active suspension and a satellite attitude control air bearing table, both controlled using a discrete Linear Quadratic Regulator (LQR) designed for each of them.

Real-Time HIL Implementation of a Single-Phase Distribution Level THSeAF Based on D-NPC Converter Using Proportional-Resonant Controller for Power Quality Platform

In this paper a single-phase transformer-less hybrid series active filter (THSeAF) based on duo-neutral-point-clamped (D-NPC) converter to address distribution level power quality is proposed to investigate experimentally the efficiency of the hardware-in-the-loop (HIL) implementation for power electronics applications. This benchmark contributes to demonstrating the capability and efficiency of such real-time implementation for smart grid power quality (PQ) analysis which requires fast switching process with small sampling time. Such applications require the compensator to address major power quality issues related to a nonlinear load. This compensator presents an efficient and reliable solution for future grid applications to overcome voltage and current related issues as well as assisting the integration of renewables for a sustainable supply. The controller extracts voltage and current harmonics to be compensated. A proportional and resonant (P + R) regulator produces switching signals for the D-NPC converter. The paper demonstrates the reliability of the HIL simulation for power electronic applications assessing power quality related issues where a wide range of switching frequency is under study. A combination of simulation and real-time results are carried out to validate the performance and viability of the HIL implementation.

마이크로컨트롤러를 이용한 BLDC 모터 구동 Hardware-in-the-Loop Simulator 개발

In this paper, we deal with the development of a HIL (Hardware-in-the-Loop) simulator for BLDC motor driving using a microcontroller. We propose a modified BLDC model for the simulation of a BLDC motor using a microcontroller. The proposed HIL simulator is developed using various peripherals of STM32F407 (ARM cortex-M4 based microcontroller). The proposed HIL simulator consists of three parts. First, the part simulating the inverter analyzes the input PWM signals to calculate the corresponding input voltage. This part detects wrong PWM signals or shoot-throughs of the half-bridge. Second, the BLDC motor part is implemented by solving the modified model equations in real time. Finally, the third part generates the output of the BLDC motor. The HIL simulator generates the Back Electromotive Force (BEMF) waveform and signals of a rotary encoder and a hall sensor. Sensor signals are generated using a timer interrupt. The BEMF waveform is implemented using DAC. Moreover, a generation method using PWM and RC filter is presented. Through experiments, we illustrate that the developed HIL simulator accurately simulates the BLDC motor. Furthermore, we confirm that the BLDC motor drive algorithm designed with the developed HIL simulator can be successfully applied to real BLDC motor driving systems.

Diseño de una plataforma de prueba de sensores virtuales para el sistema glucosa-insulina de pacientes UCI usando la técnica HIL

La simulación tradicional In Sillico (simulación computacional) no permite recrear ambientes realistas. Herramientas como hardware-in-the-loop (HIL) permiten simular en tiempo real la respuesta de un sistema ante diferentes perturbaciones y situaciones en la regulación de glucosa e insulina en las que podría encontrarse un paciente en Unidad de Cuidados Intensivos (UCI), tales como hiperglucemias o hipoglucemias. En esta investigación, se pretende desarrollar una metodología para la implementación de la técnica de simulación HIL para desarrollar una plataforma de prueba de sensores virtuales para el sistema glucosa-insulina de pacientes en UCI usando la metodología HIL y estimadores de estado, para lo cual se estableció una comunicación que permitió someter el sistema a perturbaciones en tiempo real, además de desarrollar una interfaz que permite la manipulación de las principales características y parámetros tanto del modelo como de los sensores virtuales.

INVESTIGATION OF THE RESIDUAL TROPOSPHERIC ERROR INFLUENCE ON THE COORDINATE DETERMINATION ACCURACY IN A SATELLITE LANDING SYSTEM

This paper presents the results of the investigation of the residual tropospheric error influence on coordinate determination in a GNSS landing system. The ICAO recommended methodology for residual tropospheric error calculation is taken as a basis for the present research. Special attention is paid to the troposphere refractivity index and troposphere scale height, which are derived from the well-known troposphere refraction MOPS model. A computer simulation is performed for them for the whole year and the northern hemisphere latitudes. Hardware in the loop simulation has been performed to complement the computer simulation study and investigate the situation with the residual tropospheric error calculation for the experimental GNSS satellites configuration. The experimental measurement session with a duration of about 9 hours is recorded to obtain the configuration of real navigation satellites The residual tropospheric error in meters is calculated for each navigation satellite visible during the experiment. The authors investigate the residual tropospheric error influence on the accuracy of the coordinates determined in the GNSS landing system.

Hardware in the Loop Simulation 기반 연료전지 스택 발열 예측

수소 연료전지 자동차는 운전 중 화학 반응에 의해 발생된 열이 적절히 배출되어야, 최적의 성능을 유지하고 또 장기 운전이 가능하다. 주행 시 동적으로 변동되는 부하와 이에 따른 연료전지 스택의 발열량을 실차수준에서 적절히 제어하는 것이 필요하지만, 아직 시장이 형성되지 않아 실측 데이터를 얻기 매우 어렵다. 정적 특성뿐 아니라, 운전 조건 변화에 따른 발열 특성을 모사하기 위해 HIL 시뮬레이션 기술을 적용해, 소프트웨어와 하드웨어의 적절한 조합으로 발열을 모사하였고, 스택 모사기의 발열지령은 스택 모사 모델을 통해 발생시켰다. 본 연구에서는 스택 모델의 발열 지령을 에뮬레이터가 적절히 추종하는지 확인하였으며, 또 냉각 계통을 에뮬레이터와 연동시켜 냉각에 필요한 응답 특성을 확인하였다.

Hardware in the Loop Real-time Simulation for the Associated Discrete Circuit Modeling Optimization Method of Power Converters

Due to the complicated circuit topology and high switching frequency, field-programmable gate arrays (FPGA) can stand up to the challenges for the hardware in the loop (HIL) real-time simulation of power electronics converters. The Associated Discrete Circuit (ADC) modeling method, which has a fixed admittance matrix, greatly reduces the computation cost for FPGA. However, the oscillations introduced by the switch-equivalent model reduces the simulation accuracy. In this paper, firstly, a novel algorithm is proposed to determine the optimal discrete-time switch admittance parameter, Gs, which is obtained by minimizing the switching loss. Secondly, the FPGA resource optimization method, in which the simulation time step, bit-length, and model precision are taken into consideration, is presented when the power electronics converter is implemented in FPGA. Finally, the above method is validated on the topology of a three-phase inverter with LC filters. The HIL simulation and practicality experiments verify the effect of FPGA resource optimization and the validity of the ADC modeling method, respectively.

Correlation of Hardware in the Loop Simulation (HILS) and real control vehicle flight test for reducing flight failures

After development of simulation system in laboratory tests has been completed, before implementing an autonomous flight control system directly in a high speed UAV, the system needs to be tested in a ‘transitional’ vehicle namely Clouds aeromodeling, to make sure all devices of the control system function well in manual mode, stability and auto pilot by way point. Compatibility of setting gain PID in the simulation test with the real flight test becomes a challenge to ensure the success of the vehicle in flying, as probability of flight failures or target missing is reduced. This research has successfully proven the compatibility of the gain PID in an auto pilot by way point flight condition.