Disturbance-observer-based control (DOBC) and related methods have been researched and applied in various industrial sectors in the last four decades. This survey, at first time, gives a systematic and comprehensive tutorial and summary on the existing disturbance/uncertainty estimation and attenuation techniques, most notably, DOBC, active disturbance rejection control, disturbance accommodation control, and composite hierarchical antidisturbance control. In all of these methods, disturbance and uncertainty are, in general, lumped together, and an observation mechanism is employed to estimate the total disturbance. This paper first reviews a number of widely used linear and nonlinear disturbance/uncertainty estimation techniques and then discusses and compares various compensation techniques and the procedures of integrating disturbance/uncertainty compensation with a (predesigned) linear/nonlinear controller. It also provides concise tutorials of the main methods in this area with clear descriptions of their features. The application of this group of methods in various industrial sections is reviewed, with emphasis on the commercialization of some algorithms. The survey is ended with the discussion of future directions.

/pdf/disturbance-observer-based-control-and-related-methods-an-795w6vym5o.pdf

Disturbance-Observer-Based Control and Related Methods—An Overview

This paper discusses the operational characteristics of the topologies for hybrid electric vehicles (HEV), fuel cell vehicles (FCV), and more electric vehicles (MEV). A brief description of series hybrid, parallel hybrid, and fuel cell-based propulsion systems are presented. The paper also presents fuel cell propulsion applications, more specific to light-duty passenger cars as well as heavy-duty buses. Finally, some of the major fundamental issues that currently face these advanced vehicular technologies including the challenges for market penetration are highlighted.

Topological overview of hybrid electric and fuel cell vehicular power system architectures and configurations

Thermoelectric (TE) materials have the capability of converting heat into electricity, which can improve fuel efficiency, as well as providing robust alternative energy supply in multiple applications by collecting wasted heat, and therefore, assisting in finding new energy solutions. In order to construct high performance TE devices, superior TE materials have to be targeted via various strategies. The development of high performance TE devices can broaden the market of TE application and eventually boost the enthusiasm of TE material research. This review focuses on major novel strategies to achieve high-performance TE materials and their applications. Manipulating the carrier concentration and band structures of materials are effective in optimizing the electrical transport properties, while nanostructure engineering and defect engineering can greatly reduce the thermal conductivity approaching the amorphous limit. Currently, TE devices are utilized to generate power in remote missions, solar-thermal systems, implantable or/wearable devices, the automotive industry, and many other fields; they are also serving as temperature sensors and controllers or even gas sensors. The future tendency is to synergistically optimize and integrate all the effective factors to further improve the TE performance, so that highly efficient TE materials and devices can be more beneficial to daily lives.

https://espace.library.uq.edu.au/view/UQ:722903/UQ722903_OA.pdf

High Performance Thermoelectric Materials: Progress and Their Applications

Evaluating automobile fuel/propulsion system technologies

This paper gives a comprehensive overview on disturbance/uncertainty estimation and attenuation (DUEA) techniques in permanent-magnet synchronous motor (PMSM) drives. Various disturbances and uncertainties in PMSM and also other alternating current (ac) motor drives are first reviewed which shows they have different behaviors and appear in different control loops of the system. The existing DUEA and other relevant control methods in handling disturbances and uncertainties widely used in PMSM drives, and their latest developments are then discussed and summarized. It also provides in-depth analysis of the relationship between these advanced control methods in the context of PMSM systems. When dealing with uncertainties, it is shown that DUEA has a different but complementary mechanism to widely used robust control and adaptive control. The similarities and differences in disturbance attenuation of DUEA and other promising methods such as internal model control and output regulation theory have been analyzed in detail. The wide applications of these methods in different ac motor drives (in particular in PMSM drives) are categorized and summarized. Finally, the paper ends with the discussion on future directions in this area.

/pdf/disturbance-uncertainty-estimation-and-attenuation-3dyfo50kft.pdf

Disturbance/Uncertainty Estimation and Attenuation Techniques in PMSM Drives—A Survey

The control algorithm based on the uncertainty and disturbance estimator (UDE) is a robust control strategy and has received wide attention in recent years. In this paper, the two-degree-of-freedom nature of UDE-based controllers is revealed. The set-point tracking response is determined by the reference model, whereas the disturbance response and robustness are determined by the error feedback gain and the filter introduced to estimate the uncertainty and disturbances. It is also revealed that the error dynamics of the system is determined by two filters, of which one is determined by the error feedback gain and the other is determined by the filter introduced to estimate the uncertainty and disturbances. The design of these two filters are decoupled in the frequency domain. Moreover, after introducing the UDE-based control, the Laplace transform can be applied to some time-varying systems for analysis and design because all the time-varying parts are lumped into a signal. It has been shown that, in addition to the known advantages over the time-delay control, the UDE-based control also brings better performance than the time-delay control under the same conditions. Design examples and simulation results are given to demonstrate the findings. Copyright © 2010 John Wiley & Sons, Ltd.

Design of UDE-based controllers from their two-degree-of-freedom nature

A dynamic model for thermoelectric generator applied to vehicle waste heat recovery

A method of controlling combustion in an homogenous charge compression ignition engine through indirect mechanisms. The method utilizes a predictive model so that combustion can be controlled over a wide range of operating conditions while maintaining optimum operation with respect to efficiency and emissions. The methods include an adaptive aspect, which allows the predictive model to be updated if deemed necessary. Furthermore, the methods include a model with a plurality of control modes. A control mode can be chosen to optimize the engine for one of a plurality of output characteristics, including response time, efficiency, or emissions characteristics.

A method of controlling combustion in a homogenous charge compression ignition engine

https://hal.archives-ouvertes.fr/hal-00485511/document

Thermal efficiency improvement in high output diesel engines a comparison of a Rankine cycle with turbo-compounding

In this paper, a fuzzy-tuned equivalent consumption minimization strategy (F-ECMS) is proposed as an intelligent real-time energy management solution for a conceptual diesel engine-equipped heavy duty hybrid electric vehicle (HEV). In the HEV, two electric motors/generators are mounted on the turbocharger shaft and engine shaft, respectively, which can improve fuel efficiency by capturing and storing energy from both regenerative braking and otherwise wasted engine exhaust gas. The heavy duty HEV frequently involved in duty cycles characterized by start–stop events, especially in off-road applications, whose dynamics is analyzed in this paper. The on-line optimization problem is formulated as minimizing a cost function in terms of weighted fuel power and electric power. In the cost function, a cost factor is defined for both improving energy transmission efficiency and maintaining the battery energy balance. To deal with the nonexplicit relationship between HEV fuel economy, battery state of charge (SOC), and control variables, the cost factor is fuzzy tuned using expert knowledge and experience. In relation to the fuel economy, the air-fuel ratio is an important factor. An online search for capable optimal variable geometry turbocharger (VGT) vane opening and exhaust gas recirculation (EGR) valve opening is also necessary. Considering the exhaust emissions regulation in diesel engine control, the boundary values of VGT and EGR actuators are identified by offline design-of-experiment tests. An online rolling method is used to implement the multivariable optimization. The proposed method is validated via simulation under two transient driving cycles, with the fuel economy benefits of 4.43% and 6.44% over the nonhybrid mode, respectively. Compared with the telemetry equivalent consumption minimization strategy, the proposed F-ECMS shows better performance in the sustainability of battery SOC under driving conditions with the rapid dynamics often associated with off-road applications.

/pdf/real-time-energy-management-for-diesel-heavy-duty-hybrid-3kgk6wl2f5.pdf

Richard Stobart

Papers

Design of UDE-based controllers from their two-degree-of-freedom nature

A dynamic model for thermoelectric generator applied to vehicle waste heat recovery

A method of controlling combustion in a homogenous charge compression ignition engine

Thermal efficiency improvement in high output diesel engines a comparison of a Rankine cycle with turbo-compounding

Real-Time Energy Management for Diesel Heavy Duty Hybrid Electric Vehicles