Backstepping Sliding Mode-based Model-free Control of Electro-hydraulic Systems

Hoai Vu Anh Truong,TRINH HOAI AN,안경관 사단법인 유공압건설기계학회 2022 드라이브·컨트롤 Vol.19 No.1

This paper presents a model-free system based on a framework of a backstepping sliding mode control (BSMC) with a radial basis function neural network (RBFNN) and adaptive mechanism for electro-hydraulic systems (EHSs). First, an EHS mathematical model was dedicatedly derived to understand the system behavior. Based on the system structure, BSMC was employed to satisfy the output performance. Due to the highly nonlinear characteristics and the presence of parametric uncertainties, a model-free approximator based on an RBFNN was developed to compensate for the EHS dynamics, thus addressing the difficulty in the requirement of system information. Adaptive laws based on the actor-critic neural network (ACNN) were implemented to suppress the existing error in the approximation and satisfy system qualification. The stability of the closed-loop system was theoretically proven by the Lyapunov function. To evaluate the effectiveness of the proposed algorithm, proportional-integrated-derivative (PID) and improved PID with ACNN (ACPID), which are considered two complete model-free methods, and adaptive backstepping sliding mode control, considered an ideal model-based method with the same adaptive laws, were used as two benchmark control strategies in a comparative simulation. The simulated results validated the superiority of the proposed algorithm in achieving nearly the same performance as the ideal adaptive BSMC.

Comprehensive Control Strategy and Verification for PEM Fuel Cell/Battery/Supercapacitor Hybrid Power Source

Hoai-An Trinh,Hoai Vu Anh Truong,Minh-Duc Pham,Tri Cuong Do,Hong-Hee Lee,Kyoung Kwan Ahn 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.10 No.2

Using renewable energy is becoming a new tendency for vehicular applications to reduce fossil fuel consumption and minimize greenhouse gas emissions. Well-known as an eco-friendly energy source, the proton exchange membrane fuel cell (PEMFC) is extensively used in hybrid power systems to achieve the objective of zero-emission and air protection. However, this type of fuel cell offers slow dynamics and cannot adapt to abrupt load variations when used as a primary energy source. To overcome this shortcoming, battery (BAT) and/or supercapacitor (SC) are supplemented as auxiliary sources. In this paper, an innovative energy management strategy (EMS) for a PEMFC/BAT/SC hybrid power source (HPS) is proposed to improve the accuracy of power distribution from energy sources to the load. In detail, according to different characteristics of energy sources, a frequency decoupling (FD) method is designed to determine the required currents for PEMFC, BAT, and SC based on the load power demand. Besides, an adaptive DC bus control loop is utilized to guarantee a stable DC output voltage by using the BAT. The proposed EMS is simulated in a MATLAB/Simulink environment and experimentally implemented with a real-time DSP TMS320F28379D controller board. Subsequently, a test bench of a 200 W PEMFC, 24 V–12 Ah battery, and 25 V–60 F supercapacitor is conducted for experimental validation. The obtained results show that the proposed EMS is effective to coordinate energy flows between the three used sources and enhance the fuel cell performance in a hybrid power system.

Optimization-Based Fuzzy Energy Management Strategy for PEM Fuel Cell/Battery/Supercapacitor Hybrid Construction Excavator

Hoang Vu Dao,Xuan Dinh To,Hoai Vu Anh Truong,Tri-Cuong Do,Cong Minh Ho,Tri Dung Dang,안경관 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.8 No.4

Fuel cell hybrid electric construction equipment (FCHECE) is known as a promising solution to achieve the goal of energy saving and environment protection. Energy management strategy is a key technology of FCHECE, which splits the energy fl ow between power sources. This paper presents a novel optimal energy management strategy for a hybrid electric-powered hydraulic excavator system to enhance power performance, power sources lifespan, and fuel economy. As for the proposed powertrain configuration, fuel cell serves as a primary energy source, and supercapacitor and battery are considered as energy storages. The integration of supercapacitor and battery in fuel cell vehicle has advantages of improving power performance and storing the regenerative energy for future usage. An energy management strategy based on fuzzy logic control and a rule-based algorithm is proposed to effectively distribute the power between the three sources and reuse the regenerative energy. Furthermore, the parameters of the fuzzy logic system are optimized using the combination of a backtracking search algorithm which provides a good direction to the global optimal region and sequential dynamic programming as a local search method to fi ne-tune the optimal solution in order to reduce the hydrogen consumption and prolong the lifetime of the power sources. Simulation results show that the proposed energy management strategy enhances the vehicle performance, improves fuel economy of the FCHECE by 10.919%, increase battery and supercapacitor charge-sustaining capability as well as efficiency of the fuel cell system.

Recent Control Technologies for Floating Offshore Wind Energy Systems: A Review

Kwangtae Ha,Hoai Vu Anh Truong,Tri Dung Dang,안경관 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.8 No.1

This paper presents the recent control technologies being researched for floating off shore wind energy system (FOWES). FOWES has been getting many attentions recently as an alternative energy system utilizing vast sustainable wind resource away from land with little restriction by human societies, artificial and natural obstacles. However, not only due to the harsh environmental conditions such as strong wind, wave, and current, but also due to the platform motions such as surge, sway, heave, pitch, roll, and yaw, there could occur many problems including less energy capture than expected, frequent emergency stops, turbine structural instability, and fatigues resulting in early failures, which stay the levelized cost of energy (LCOE) still high compared to conventional fixed off shore wind energy system. These risks could be lowered by operating the turbine close to the optimum point and harvesting wind energy efficiently even under strong wind conditions with the properly applied control technologies, while reducing the loads on structural components. Many researches have been actively going on not only by numerical approaches, but also by experimental tests. This study is wrapping the most recent researches on control technologies for promising floating off shore wind energy system according to different substructure designs such as a spar type, semi-submergible type, tension-leg platform (TLP) type, and barge type, and discusses about its challenges as well.

Adaptive sliding mode control with backstepping technique for hydraulic manipulator

Duc-Thien Tran,Hoai Vu Anh Truong,Xuan Dinh To,Bomoon Seo,Kyoung Kwan Ahn 제어로봇시스템학회 2018 제어로봇시스템학회 국내학술대회 논문집 Vol.2018 No.5

In this paper, an adaptive sliding mode control with backstepping technique is proposed regarding to controlling position of a hydraulic manipulator in joint space. The proposed control is developed based on sliding mode control, backstepping technique, and radial basis function neural network (RBFNN). In the hydraulic manipulator, the primary torques are generated by hydraulic actuators, so it helps to extend load carrying capacity of the manipulator. But it brings some challenges, such as coupling issues, uncertainties in parameter, modeling, and external disturbance in mechanical and hydraulic dynamics. The properties of the proposed control can deal to these problems to guarantee the stability requirements and improve the precision. The sliding mode control with backstepping technique is used to handle the coupling issues and to ensure the stability and robustness. Additionally, two adaptive approximators based on RBFNN compensate the uncertainties and improve the precision. Some simulations are implemented and compared to other controllers to exhibit the effectiveness of the proposed control.

Adaptive Nonsingular Fast Terminal Sliding mode Control of Robotic Manipulator Based Neural Network Approach

Duc-Thien Tran,Hoai Vu Anh Truong,Kyoung Kwan Ahn 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.22 No.3

The paper addresses an adaptive robust position control for tracking control of a manipulator under the presence of the uncertainties, such as variant payload, modeling error, friction, and external disturbance. The proposed control uses radial basis function neural networks (RBFNN)s to approximate and cancel the uncertainties. The nonsingular fast terminal sliding mode control (NFTSMC) of the proposed control is developed to guarantees a finite-time convergence and to solve the singular issue of the terminal sliding mode control. Moreover, the learning laws are derived from the Lyapunov approach to ensure the stability and robustness of the whole system. The proposed control is compared with other controllers through both simulations and experiments on a 3-DOF manipulator to exhibit its efficiency with the variant payload and the uncertainties.

Maximum Power Point Tracking and Output Power Control on Pressure Coupling Wind Energy Conversion System

Do, Hoang Thinh,Dang, Tri Dung,Truong, Hoai Vu Anh,Ahn, Kyoung Kwan Institute of Electrical and Electronics Engineers 2018 IEEE transactions on industrial electronics Vol.65 No.2

<P>This paper proposed a combined method for wind energy conversion system using pressure coupling (PC) hydrostatic transmission. The operation strategy is the combination of maximizing power point tracking at the input power and stabilizing the output power. The maximum power point tracking method is to control the turbine speed for tracking the optimal tip speed ratio (TSR). For maximizing the input power, a PID controller and a sliding mode controller are applied for speed control to track a predefined speed that is calculated from the optimal TSR. The output power is stabilized by using a high-pressure accumulator for accumulating and compensating the power. The driven speed of the generator is controlled by the PC principle, using a PID controller and an adaptive fuzzy sliding mode controller. Experiments are carried out to verify the proposed method. The overall efficiency in several wind speed profiles is about 40%.</P>

Design, Modeling and Analysis of a PEM Fuel Cell Excavator with Supercapacitor/Battery Hybrid Power Source

Tri Dung Dang,Tri Cuong Do,Hoai Vu Anh Truong,Cong Minh Ho,Hoang Vu Dao,YU YINGXIAO,정은진,안경관 사단법인 유공압건설기계학회 2019 드라이브·컨트롤 Vol.16 No.1

The objective of this study was to design and model the PEM fuel cell excavator with supercapacitor/battery hybrid power source to increase efficiency as well as eliminate greenhouse gas emission. With this configuration, the system can get rid of the internal combustion engine, which has a low efficiency and high emission. For the analysis and simulation, the governing equations of the PEM system, the supercapacitor and battery were derived. These simulations were performed in MATLAB/Simulink environment. The hydraulic modeling of the excavator was also presented, and its model implemented in AMESim and studied. The whole system model was built in a co-simulation environment, which is a combination of MATLAB/Simulink and AMESim software. The simulation results were presented to show the performance of the system.

A study on modeling of a hybrid wind wave energy converter system

Tri Dung Dang,Cong Binh Phan,Hoai Vu Anh Truong,Chau Duy Le,Minh Tri Nguyen,Kyoung-Kwan Ahn 제어로봇시스템학회 2016 제어로봇시스템학회 국제학술대회 논문집 Vol.2016 No.10

A model of a hybrid wind wave energy converter (HWWEC) system is proposed in this paper. The HWWEC includes two wave buoys and a vertical axis wind turbine (VAWT) system, which co-works to drive a generator. Wave buoys are arranged in an arc pattern to capture efficiently wave energy from many directions. The hydrodynamic forces are calculated by the Wave Analysis at Massachusetts Institute of Technology WAMIT software. In order to bring the system into resonance with the incident wave frequencies, a variable inertia hydraulic flywheel is employed so that the power output is maximized. Specifications and working principle of the whole system are presented and described. WEC unit model and hybrid mechanism are also presented. Simulations are carried out to evaluate the performance the HWWEC with the given specifications. Then, simulation results under some phase differences are taken to investigate the influence on the overall efficiency.

Design, Modeling and Analysis of a PEM Fuel Cell Excavator with Supercapacitor/Battery Hybrid Power Source

Dang, Tri Dung,Do, Tri Cuong,Truong, Hoai Vu Anh,Ho, Cong Minh,Dao, Hoang Vu,Xiao, Yu Ying,Jeong, EunJin,Ahn, Kyoung Kwan The Korean Society for Fluid Power and Constructio 2019 드라이브·컨트롤 Vol.16 No.1

The objective of this study was to design and model the PEM fuel cell excavator with supercapacitor/battery hybrid power source to increase efficiency as well as eliminate greenhouse gas emission. With this configuration, the system can get rid of the internal combustion engine, which has a low efficiency and high emission. For the analysis and simulation, the governing equations of the PEM system, the supercapacitor and battery were derived. These simulations were performed in MATLAB/Simulink environment. The hydraulic modeling of the excavator was also presented, and its model implemented in AMESim and studied. The whole system model was built in a co-simulation environment, which is a combination of MATLAB/Simulink and AMESim software. The simulation results were presented to show the performance of the system.