Mihael Cipek

University of Zagreb · Faculty of Mechanical Engineering and Naval Architecture - Department of Robotics and Production System Automation

The progress of transport technology and the transition from fossil to renewable energy sources have also changed the way of managing the transport system and wider infrastructure. This is most visible in cities due to their rapid growth. Cities are rapidly digitizing in leading new technologies and services to citizens in a new way. Also, the EU r...

Lithium-titanate currently represents state-of-the-art technology in lithium secondary batteries that is characterized by exceptional thermal stability and operational safety levels. This makes them particularly interesting for highly demanding stationary energy storage applications. In practical field operations, minimizing the recharging time fro...

Among the many rechargeable lithium batteries, lithium-titanate, or lithium-titanium oxide cells are characterized by the highest thermal stability and operational safety levels, which makes them particularly well suited for highly demanding applications. This paper presents the results of experimental characterization of a lithium-titanate battery...

In this Encyclopaedia contribution, we examine the integration of information and communication technologies and remote sensor networks within the context of Industry 4.0. This leveraging of information pertaining to transportation infrastructure promises to bolster energy efficiency, safety, and resilience in the transportation ecosystem. Furtherm...

This article presents a review of cutting-edge technologies poised to shape the future of railway transportation systems, focusing on enhancing their intelligence, safety, and environmental sustainability. It illustrates key aspects of the energy-transport-information/communication system nexus as a framework for future railway systems development....

Nowadays, railway vehicles are typically equipped with electric traction, and the required traction power can be estimated from the longitudinal train dynamics (train speed and acceleration), which effectively determines the traction drive torque and speed (traction power) requirements. This required power can then be used for defining the on-board...

The utility of Unmanned Aerial Vehicles (UAVs) in various industries and applications, such as aerial photography, surveying, and inspection, is being demonstrated daily. However, the limited flight time of UAVs remains a major bottleneck, due to the relatively low energy density of lithium polymer batteries, which are commonly used as a convention...

Among the many currently available rechargeable lithium battery chemistries, lithium-titanante battery cells are characterized by highest thermal stability and operational safety levels, which makes them particularly well suited for use under demanding operating conditions. This paper presents the design of a constant-current/constant voltage batte...

Among the many rechargeable lithium batteries, lithium-titanante cells are characterized by highest thermal stability and operational safety levels, which makes them particularly well suited for highly demanding applications. This paper presents the results of experimental characterization of a lithium-titanate battery cell for the purpose of build...

This paper presents the novel design of a constant-current/constant-voltage charging control strategy for a battery cell. The proposed control system represents an extension of the conventional constant-current/constant-voltage charging based on the so-called cascade control system arrangement with the adaptation of the battery charging current bas...

Hybrid electric propulsion, using batteries for energy storage, is making significant inroads into railway transportation because of its potential for notable fuel savings and the related reductions in greenhouse gases emissions of hybrid railway traction over non-electrified railway lines. Due to the inherent complexity of hybridized powertrains,...

This paper presents a method for the estimation of key parameters of limit cycle oscillations (amplitude and frequency) during a relay experiment used for automatic tuning of proportional-integral (PI) and proportional-integral-derivative (PID) feedback controllers. The limit cycle parameter estimator is based on the first-order extended Kalman fil...

This paper presents a single-step automatic tuning procedure and an estimator of key parameters of the drill-string system used in deep drilling applications aimed at precise tuning of an external vibration suppression system based on speed control loop of the drilling electrical drive tuned for “stiff” motor-side speed control (the so-called speed...

This paper deals with the control of the direct-current to direct-current (DC/DC) energy conversion between high voltage and low voltage systems within a hybrid electric power-train structure intended to be used in articulated forestry tractor, also known as skidder. Electrical part of the hybrid power-train is modeled for the case of utilization o...

Increasing demands in terms of reducing the cost of running forestry machines along with the regulatory pressures for lower exhaust emissions encourages the usage of hybrid powertrains in field applications. Hybrid power-trains consist of two or more different energy sources, which leads to many open questions in terms of energy management control,...

Nowadays, railway vehicles are being increasingly equipped with hybrid electric power-trains in order to provide significant gains in fuel economy and reductions in greenhouse gases emissions. Since hybrid power-trains are complex electromechanical systems, optimal energy management is crucial in order to achieve minimum possible fuel consumption....

Forestry vehicles have been increasingly equipped with hybrid electric power-trains in order to provide significant gains in fuel economy, and also to facilitate reductions in greenhouse gases emissions. Due to the fact that hybrid power-trains consist of two or more different energy sources, many questions in terms of power-train components sizing...

The paper presents a detailed review of state-of-the art technologies for the future development of smarter, safer and greener railway transportation systems. Firstly, the paper presents a comprehensive overview of current challenges in railway transportation, followed by emerging propulsion technologies that are key for sustainable transportation.

This paper presents a control system design methodology suitable for the drill-string rotary drive for deep drilling applications. The active damping control system automatic tuning is performed by designing the drill-string parameter estimator which simultaneously calculates the drive resonance frequency and inertia using a single limited-duration...

This paper presents the design of a constant-current/constant voltage charging control system for a battery cell using the so-called cascade control system arrangement with the superimposed control level commanding the battery charging current reference to the inner current control loop. The superimposed control level is realized as a double feedba...

Hybrid powertrain presents a viable solution for reducing fuel consumption through powertrain electrification while simultaneously being independent from the electric grid or a charging station. Due to the fact that articulated forestry tractors (skidders) belong to the class of forestry machinery which is intended for field use, this operating ind...

This paper presents the design of an extended Kalman filter (EKF) as a state-of-charge (SoC) estimator for a lithium–titanate (LTO) battery cell. The design is based on a Thevenin model of the equivalent battery electrical circuit with two parallel resistive-capacitive (RC) elements for the emulation of electrolyte polarization effects. The effecti...

This paper presents the use of track condition data for predictive traction control of a diesel-electric locomotive-driven freight train using the data collected from the virtual remote wireless sensor network within a simulation model comprising wheel vs. track friction coefficient dependent on ambient temperature and relative humidity. The simula...

This paper presents two designs of constant-current/constant voltage battery charging control systems in the form of a cascade control system arrangement with the superimposed proportional-integral (PI) controller commanding the battery charging current reference to the inner PI controller-based current control loop. The superimposed control level...

Deep drilling operations are typically needed when producing deep wells for hydrocarbon exploitation or geothermal energy applications. Since a notable portion of existing deep drilling rigs are still fielding manually operated draw-works (hoist) drum mechanical brake actuators, their usage puts notable constraints on the quality of borehole produc...

This paper investigates potential uses of a novel direct driven electro-hydraulic systems for articulated forestry tractors (skidders), due to these systems having notably higher energy efficiencies compared to classical electro-hydraulic systems that are currently being used in skidders for steering, lifting the front and the rear plate, as well a...

In order to meet the increasingly stricter emissions’ regulations, road vehicles require additional technologies aimed at the reduction of emissions from the internal combustion engine (ICE). A favorable solution from the standpoint of costs and simplicity of integration is a 48-V electrical architecture utilizing a low-voltage/high-power induction...

This paper presents the results of modeling, control system design and simulation verification of a hybrid-electric drive topology suitable for power flow control within unmanned aerial vehicles (UAVs). The hybrid power system is based on the internal combustion engine (ICE) driving a brushless DC (BLDC) generator supplying the common DC bus used f...

A notable portion of contemporary deep drilling rigs are still equipped with manually-operated lever-based draw-works (hoist) drum mechanical brake actuators, which are used for weight-on-bit (WoB) and rate-of-penetration (RoP) control. In order to meet increasingly stringent requirements on the WoB/RoP control performance, including completely aut...

Nowadays there are increasing demands in terms of reducing the cost of running forestry machines along with the regulatory pressures for lower exhaust emissions to improve the ecological indices and reduction of acoustic noise in order to comply with increasingly more stringent industry ergonomic guidelines. Therefore, the producers of forestry equ...

Hybrid powertrain presents a viable solution for reducing fuel consumption achieved by a powertrain electrification while maintaining the independence from the electric grid or a charging station. Due to the fact that skidders belong to the class of forestry machinery which is intended for field use, this operating independence is very important. A...

Gradually stricter demands on carbon-dioxide (CO2) emissions reduction imposed by the European Union have proved as an efficient motivator for automobile manufacturers to develop novel technologies in order to electrify their respective fleets. Starting from 2020, the average emissions target for a manufacturer’s fleet is set below 95 g CO2/km, whi...

Off-road vehicles are increasingly being equipped with hybrid electric powertrains in order to improve their fuel economy, and, consequently, to facilitate notable reductions in greenhouse gases emissions. The hybrid electric power-train apparently offers a favorable solution that can meet the above requirements for the propulsion of articulated fo...

This paper presents two designs of constant-current/constant voltage battery charging control systems in the form of a cascade control system arrangement with the superimposed proportional-integral (PI) controller commanding the battery charging current reference to the inner PI controller-based current control loop. The superimposed control level...

The paper presents the speed control system design and simulation verification of a petroleum drilling system aimed at effective suppression of drill-string torsional vibrations in legacy drilling drives featuring mature series-wound direct-current motor drive technology. The vibration suppression system is based on the external damping feedback lo...

Hybrid powertrains have already proven themselves as viable solutions for reducing fuel consumption while maintaining the same operating performance of conventional ones, which is achieved by using an additional energy source in combination with energy recuperation. Many forestry machinery and tools which are intended for field use are hydraulics-b...

In this paper, a novel energy-efficient Direct Driven Hydraulic (DDH) drive is made in parallel with a classical valve-controlled proportional electrohydraulic system. In the proposed concept asymmetrical hydraulic cylinder is controlled with two reversible pumps directly connected to a servo motor. Due to direct control of the oil flow, such syste...

The paper considers a novel approach to heavy-haul of railway freight by means of combined operation of conventional diesel-electric and battery-electric locomotives either in single or joint (tandem) operation. A backward-looking quasi-static model of a battery-electric locomotive is proposed, based on the undercarriage of a decommissioned convent...

This paper presents a control system design methodology for the drill-string rotary drive and draw-works hoist system aimed at their coordinated control for the purpose of establishing a fully-automated mechatronic system suitable for borehole drilling applications. Both the drill-string rotary drive and the draw-works hoist drive are equipped with...

Over the last decade, off-road vehicles have been increasingly hybridized through powertrain electrification in terms of additional electrical machine-based propulsion and battery energy storage, with the goal of achieving significant gains in fuel economy and reductions in greenhouse gases emissions. Since hybrid powertrains consist of two or more...

In recent years, road vehicles are being increasingly equipped with hybrid electric power-trains in order to provide significant gains in fuel economy and reductions in greenhouse gases emissions. Since hybrid power-trains consist of two or more different energy sources, many of their variants are present nowadays which leads to many open questions...

This paper presents a generator set speed control system within a hybrid propulsion based on an internal combustion engine (ICE) as primary energy source for a hypothetical multi-rotor unmanned aerial vehicle (UAV). The engine-generator set rotational speed is estimated based on rotor position sensing from embedded Hall sensors and armature current...

The paper presents the hybrid propulsion control system design for a multi-rotor unmanned aerial vehicle (UAV) equipped with internal combustion engine (ICE) and generator as a primary energy source and direct-current (DC) power system with DC/DC buck converters controlling the input voltage of propeller electrical drives. Control system design is...

The paper presents a hypothetical conversion of a conventional cable skidder powertrain to its hybrid version. Simulations of skidder operation were made for two existing forest paths, based on the technical characteristics of the engine, transmission system and the characteristics of the winch. Fuel and time consumption were calculated per working...

This paper presents the use of track condition data from the virtual remote wireless sensor network within a simulation model of a battery-hybrid diesel-electric locomotive-driven freight train for a realistic mountain railway route simulation scenario. Simulation model includes the point-mass model of freight train longitudinal motion dynamics sub...

Nowadays there are increasing demands in terms of reducing the cost of running forestry machines along with the regulatory pressures for lower exhaust emissions to improve the ecological indices and reduction of acoustic noise in order to better comply with industry ergonomic guidelines. Therefore, the producers of forestry equipment are increasing...

The European Union and other countries around the world are implementing policies that aim to improve the transportation energy efficiency with sustainability as their ultimate goal. The ultimate goal of transport electrification is achieving zero CO2 emissions. However, many railway lines in Europe that are rather lengthy and are characterized by...

This paper presents a hypothetical conversion of a conventional articulated forestry tractor known as skidder to its hybrid counterpart by incorporating a battery energy storage system. Starting from the basic parameters of 84 kW diesel-powered skidder currently found in the national forestry company fleet, the quasi-static model of the skidder is...

One of the key limitations of the currently deployed multirotor aircraft and similar unmanned aerial vehicles (UAVs) is the rather low capacity and non-negligible weight of the state-of-the art lithium-based batteries, resulting in rather low flight mission endurance (flight range), payload restrictions and manoeuvring limitations. On the other han...

This paper investigates the effectiveness of a parallelized low-cost DC/DC converter array within the power distribution system of a hybrid-propulsion multi-rotor unmanned aerial vehicle (UAV). In conventional multirotor UAVs, lithium polymer (LiPo) batteries are almost exclusively used as power sources. Since they are characterized by rather low e...

This paper presents a control system design methodology for the drill-string rotary drive and draw-works hoist system aimed at mature drilling rig retrofitting. The rotary drive is equipped with an active damping speed control system featuring a proportional-integral speed controller readily available within modern controlled electrical drives, ext...

Design of fuzzy logic system for traffic scheduling is presented for the case of bidirectional traffic of personal rapid transit rail vehicles under reduced traffic flow conditions due to obstruction, which mandates diverting of local traffic. The proposed traffic scheduling system has been verified against the conventional traffic control system u...

Weather conditions can affect train dynamics and wheels adhesion, thus compromising transportation safety. The fifth generation broadband wireless networks, with distributed sensors arrays may provide more accurate estimation of track conditions. This paper proposes the use of track condition data from remote sensors in order to adapt the freight t...

Over the last two decades, vehicles have been increasingly equipped with hybrid electric power-trains in order to provide significant gains in fuel economy, and also reductions in greenhouse gases emissions. Due to the fact that hybrid power-trains consist of two or more different energy sources, many of their variants are present nowadays. This le...

Weather conditions have a significant impact on railroad traffic operation and maintenance, especially under icy conditions, and in the cases of substantial snowfall, rain, wind, fog, and temperature extremes. These can affect the train dynamics by increasing movement resistances while also lowering track to wheels adhesion, which is necessary for...

This paper presents a control system design methodology for the drill-string rotary drive and draw-works hoist system aimed at their coordinated control for the purpose of establishing a fully-automated mechatronic system suitable for geothermal drilling applications. Both the drill-string rotary drive and the draw-works hoist drive are equipped wi...

During petroleum drilling, the drill-string electrical drive is prone to significant torsional vibrations caused by tool vs. rock stick-slip friction and drill-string torsional compliance, which may cause mechanical failure and excessive wear of critical parts of the drilling system. Hence, the drill-string electrical drive needs to be equipped wit...

The paper presents the design methodology and experimental verification of petroleum drilling system aimed at effective suppression of drill-string torsional vibrations. The vibration suppression system is based on the external damping feedback loop featuring a simple drill-string torque estimator and a reference correction term in the speed target...

A design of current control system and grid synchronization algorithm is presented for a single-phase grid-tied inverter. A dual current controller is presented, wherein a proportional-resonant controller controls the principal component of output current, while a proportional-integral controller is used for inverter direct current component suppre...

A novel approach to hybrid hydraulic vehicles drive component sizing methodology based on the Willans Line method is proposed in this paper. The proposed method is used to develop a scalable mathematical model of hydraulic unit efficiency maps, thus helping the designer regarding an appropriate hydraulic unit choice when target unit data is difficu...

This paper presents a hypothetical conversion of a conventional heavy haul diesel-electric locomotive to its hybrid counterpart by incorporating a battery energy storage system. Starting from the basic parameters of a 1.6 MW diesel-electric locomotive currently found in the national railway company locomotive fleet, the quasi-static model of the lo...

This contribution outlines the design of electric vehicle direct-current (DC) bus control system supplied by a battery/ultracapacitor hybrid energy storage system, and its coordination with the fully electrified vehicle driveline control system. The control strategy features an upper-level DC bus voltage feedback controller and a direct load compen...

This paper presents a hypothetical conversion of a conventional heavy haul diesel-electric locomotive to its hybrid counterpart by incorporating a battery energy storage system. Starting from the basic parameters of a 1.6 MW diesel-electric locomotive currently found in the national railway company locomotive fleet, the quasi-static model of the lo...

This paper presents the design of droop-based control system and the cascade control system based on dynamic power distribution strategy for a direct-current microgrid featuring a hybrid battery/ultracapacitor energy storage system. In particular, power converter direct-current bus voltage control systems have been designed based on the damping opt...

A design of a hybrid battery/ultracapacitor energy storage system (ESS) DC microgrid control system is based on droop and cascade control. The proposed control systems are augmented by feed-forward load compensators aimed at achieving effective load disturbance rejection. The effectiveness of different control schemes is investigated via closed-loo...

This paper presents the design and detailed experimental verification of oil drilling automation systems, which included draw-works hoist-based Weight-on-Bit/Rate-of-Penetration (WoB/RoP) automatic drilling system, and active damping speed control system of the drill-string rotary electrical drive based on the Hardware-in-the-Loop (HIL) laboratory...

This paper presents the results of modeling and parameterization of the high-altitude wind energy system ground station power-plant equipped with a generator/motor unit as a primary power source tethered to the airborne module via a winch system, an ultracapacitor energy storage system, and grid inverter connected to the common direct-current link....

A novel approach to hybrid hydraulic vehicles drive component sizing methodology based on the Willans Line method is proposed in this paper. The proposed method is used to develop a scalable mathematical model of hydraulic unit efficiency maps, thus helping the designer regarding an appropriate hydraulic unit choice when target unit data is difficu...

A notable portion of contemporary oil drilling rigs are still equipped with mature drilling equipment such as traditional speed-controlled drives being used without regard for drill-string compliance-related stick-slip effect, which shortens the useful life of the tool (drill-bit) and other drill-string drive mechanical components. Moreover, the dr...

Over the last 30 years a number of airborne module-based wind energy concepts have been proposed within the last decade in order to offer a possibility of harnessing the energy of high-altitude/high-speed, and, thus, to provide a viable alternative to ground-based wind-turbine systems which have steadily reached their performance peak due to blade...

A DC bus control strategy of an actively-controlled battery/ultracapacitor hybrid energy storage system for a full EV is presented in this paper. The control strategy is based on the PI DC bus voltage controller, wherein the DC bus voltage target is determined based on motor voltage demand. A feed-forward load compensator is also included in order...

A dynamic programming-based algorithm is used for off-line optimisation of control variables of a series-parallel extended range electric vehicle powertrain. The aim is to minimise the fuel and/or electricity consumption, subject to battery state-of-charge constraints and physical limits of different powertrain variables. The optimised control vari...

There is a strong tendency of development and application of different types of electric vehicles (EV). This can clearly be beneficial for transport systems in terms of making it more efficient, cleaner, and quieter, as well as for energy systems due to the grid load leveling and renewable energy sources exploitation opportunities. The latter can b...

There is a strong tendency of development and application of different types of electric vehicles (EV). This can clearly be beneficial for transport systems in terms of making it more efficient, cleaner, and quieter, as well as for energy systems due to the grid load leveling and renewable energy sources exploitation opportunities. The latter can b...

In an authors' previous SAE publication, an energy management control strategy has been proposed for the basic, charge-depleting/charge-sustaining (CD/CS) regime of an Extended Range Electric Vehicle (EREV). The strategy is based on combining a rule-based controller, including a state-of-charge regulator, with an equivalent consumption minimization...

The paper proposes a power-split hybrid electric vehicle control strategy that combines a rule- based controller, including a state-of-charge controller and engine start–stop logic, with a precisely formulated equivalent consumption minimization strategy. A one-dimensional directional search-based instantaneous equivalent consumption minimization s...

A dynamic programming-based algorithm is developed and used for off-line optimization of range extended electric vehicle power train control variables over standardized certification driving cycles. The aim is to minimize the fuel consumption subject to battery state-of-charge constraints and physical limits of different power train variables. The...

A simulation model of a two mode power-split hybrid electric vehicle (HEV) is proposed in this paper for the purpose of HEV dynamics analysis and control system design. The bond graph methodology is used to model dominant dynamic effects of the mechanical part of the HEV transmission. Simple quasi-static battery model, the environment model, the ti...

A back propagation through time-like conjugate gradient-based algorithm is used for off-line optimization of a series-parallel hybrid power train control variables over standardized certification driving cycles. The aim is to minimize the fuel consumption subject to battery state-of-charge constraints. The optimization is carried out using a simpli...

The bond graph method is used to model kinematics and dynamics of various one-mode and two-mode series-parallel configurations of Hybrid Electric Vehicle (HEV) transmissions. The bond graph method is also used to analyse the power flow of the considered transmissions in electric variator and full-hybrid operating modes. The analysis is illustrated...

The bond graph method is used to model dynamics of various one-mode and two-mode series-parallel configurations of hybrid electric vehicle power trains. Proper handling of causalities results in minimum-realization models convenient for various simulation, analysis, and control design studies. The same, unified model structure can be used to descri...

The bond graph method is used to analyze the power flow in typical one-mode and two-mode series-parallel hybrid electric vehicle (HEV) transmissions. The power flow analysis is conducted for two characteristic HEV transmission configurations based on electric variator without and with electric accumulation. The analysis is illustrated by numerical...