Induction Heating System Research Articles

AWS IoT Core and Amazon DeepAR based predictive real-time monitoring framework for industrial induction heating systems

AWS IoT Core and Amazon DeepAR based predictive real-time monitoring framework for industrial induction heating systems

P‐52: Novel Forming Technology of 3D Cover Glass with Induction Heating System for Curved‐Corner Display

This paper talks about new thermal forming method of 3‐dimensional box‐type cover glass with double curvature for mobile phone application. Induced heating of glass forming molds was successfully employed around edge area in order to minimize typical surface wrinkle and dent defects commonly appearing in conventional direct mold heating with heating plates. The results showed better surface qualities compared to conventional heating by optimizing mold temperature, loading pressure and 2‐dimensional initial preform shape.

Fractional-Order PID Controllers for Temperature Control: A Review

Fractional-order proportional integral derivative (FOPID) controllers are becoming increasingly popular for various industrial applications due to the advantages they can offer. Among these applications, heating and temperature control systems are receiving significant attention, applying FOPID controllers to achieve better performance and robustness, more stability and flexibility, and faster response. Moreover, with several advantages of using FOPID controllers, the improvement in heating systems and temperature control systems is exceptional. Heating systems are characterized by external disturbance, model uncertainty, non-linearity, and control inaccuracy, which directly affect performance. Temperature control systems are used in industry, households, and many types of equipment. In this paper, fractional-order proportional integral derivative controllers are discussed in the context of controlling the temperature in ambulances, induction heating systems, control of bioreactors, and the improvement achieved by temperature control systems. Moreover, a comparison of conventional and FOPID controllers is also highlighted to show the improvement in production, quality, and accuracy that can be achieved by using such controllers. A composite analysis of the use of such controllers, especially for temperature control systems, is presented. In addition, some hidden and unhighlighted points concerning FOPID controllers are investigated thoroughly, including the most relevant publications.

Liver tumor ablation enhancement by induction-heating system with bitter-like deep magnetic field coil.

The heated metal needle used for tumor thermotherapy is considered crucial for enhancing the practicality of cauterization using electromagnetic induction-heating techniques. In this study, a novel coil capable of producing a deep magnetic field is designed. In the proposed design, the coil structure is improved to enhance the intensity of the coil's deep magnetic field and its suitability for deep-tissue cauterization. Furthermore, a series of experiments are conducted using a single and consistent input current. The heating experiments are conducted at varying depths by placing the needle beneath the coil. The proposed coil significantly increases the induction-heating temperature and provides a solution to the long-standing problem of insufficient needle temperature. This research has also improved the usability of the induction-heating equipment in the field of deep tumor ablation.

Fabrication of flame-retardant magnesium alloy hollow sphere with specific gravity less than one through atmospheric foaming

Metallic hollow sphere is a kind of lightweight metal foams. Most metallic hollow spheres have been made of iron. The authors have succeeded to fabricate Mg-Al-Zn alloy hollow spheres through inert gas foaming in the previous study. In the present study, magnesium alloy hollow spheres are fabricated through atmospheric foaming. The starting material was AZX912 flame-retardant magnesium alloy plates. AZX912 alloy precursors were produced through accumulative diffusion-bonding process. Magnesium hydride powder with the total amount of 1.0 mass% was used as a foaming agent. Foaming tests were carried out in atmosphere using a high-frequency induction heating system. The foaming process was in-situ observed by the digital video camera. The AZX912 alloy precursor expanded with increasing the heating time. As a result, AZX912 alloy hollow sphere with the porosity of 50% was obtained successfully. The hollow sphere easily floated on the surface of water because of the specific gravity of 0.91 and the closed-cell structure.

Critical conditions for melting of metallic wire in induction heating system through numerical simulation and experiments

Induction heating is a novel energy source that can be utilized in the melting of metallic wires for the development of green manufacturing processes such as drop-casting and additive manufacturing. The present work aims to find out the critical radius of the feedstock wire to be melted through an induction heating system. An analytical model is developed to find an initial assessment of the feasible parameters and assists the 3D coupled electromagnetic-thermal model to study the melting behaviour of the mild steel wire. Through these models, the time required to reach the melting point of the wire for various process conditions has been investigated. The coil current and the number of turns of the coil primarily influence the melting duration of the wire. The experiments on a high-frequency induction heating system suggests that the critical wire size of 1.6 mm transfer the metal droplets at 550 A coil current, 15 mm inner coil radius, 3-turn induction coil and 353 kHz frequency. At this point, the finite element model acts as an aid to develop the experimental system and provides satisfactory results when compared with experimental data. This work effectively presents a mathematical framework where critical size of wire is identified to create molten droplets in a specific induction heating system.

The Effect of Conductive Alginate Capsules Encapsulating Rejuvenator (HealRoad Capsules) on the Healing Properties of 10 mm Stone Mastic Asphalt Mix

Conductive alginate capsules encapsulating a bitumen rejuvenator (HealRoad capsules) has demonstrated good healing abilities in pure bitumen and mortar mixes. HealRoad capsules can efficiently heal damage via induction heating. They also release the encapsulated rejuvenator, thereby rejuvenating aged bitumen. These findings indicate that HealRoad capsules and induction heating systems combined could represent a possible asphalt pavement maintenance method. This paper investigated the effect of HealRoad capsules on the mechanical performance of the 10 mm stone mastic asphalt mix and measured the damage repair (healing) efficiency of the capsules in an asphalt mix. The results indicate that in small amounts, >1%, HealRoad capsules do not degrade the mix performance (indirect tensile strength and rutting resistance) and in some cases, the HealRoad capsules actually improve mix performance, e.g., in terms of the indirect tensile strength ratio (water sensitivity). However, the HealRoad capsules are unable to stimulate induction healing due to the small volume of capsules within the mix. Further investigation demonstrated that increasing the capsules in the mix to >5% can stimulate induction heating effectively. However, it also indicated that a high content of HealRoad capsules reduces the asphalt mix strength. The study has shown that HealRoad capsules are an effective healing system for high bitumen content mixtures such as mortar mixtures but is an inefficient healing system for a full asphalt mix, such as the 10 mm stone mastic asphalt mix.

Effect of power and diameter on temperature and frequency in induction heating process of AISI 4140 steel

This research aims to design an induction heating system and to investigate the effect of power supply and specimen diameter on specimen temperature and frequency on the coil. This study began with the development of an induction heating system that made use of circulating coolers outfitted with Thermoelectric Cooler Materials (TEC). It was intended to keep the temperature of the coil and the Printed Circuit Board (PCB) as low as possible. This study used AISI 4140 steel material with diameter variations of 7 mm, 14 mm, 21 mm, and 28 mm, with power levels of 60 W, 240 W, 540 W, and 960 W. The temperature was measured using a thermocouple connected to the specimen, and the frequency value obtained was measured using an oscilloscope. The research findings show that varying the applied power affects the frequency of the coil and the temperature of the specimen, with the higher the power, the faster the temperature of the specimen rises. The 60 W power can heat the specimen at an average temperature of 470°C and a frequency of 102 kHz. When the power variation is 960 W, the temperature in the specimen is 746°C, and the frequency is 110 kHz. On the temperature and frequency gradient pattern in the 0-600 s period, there are two stages, the first of which is ferromagnetic and the second of which is paramagnetic.

Energy-efficient double belt press with integrated inductive heating system

At the Aachen Centre for Integrative Lightweight Production (AZL) of RWTH Aachen University a new double belt press with inductive heating and elastomer-coated pressure rollers has been developed and optimised within industrial AZL joint partner research projects. This machine system is patented by the AZL and available for industrial trials and also as commercial product in license. This new machine concept enables an efficient, continuous pressing process in a small installation space. The induction allows for a rapid heating of the steel belt material up to 300 °C and the elastomer pressure rollers enable surface contact during pressure application. The double belt press differs from conventional systems as it uses closed-loop controlled inductive heat input and high-temperature resistant elastomer-coated rollers for applying specific pressures up to 23 bar at maximum process temperatures up to 300 °C (current development for up to 400 °C). In extensive trials with several partners from the AZL partner network and external companies, the machine has proven to be efficient for consolidating thermoplastic composite laminates as well as for impregnating both thermoset and thermoplastic composite laminates.

Heat generation depth and temperature distribution in solar receiver tubes subjected to induction

Induction heating is commonly used in laboratory-scale facilities to replicate the heating conditions of the receiver tubes of concentrated solar power plants. This work aims at shedding light at the induction heating characteristics for such applications through the development of a multiphysics numerical model capable of replicating the experimental conditions of a molten salt loop locally heated by an induction heater. In the experiments, a stainless steel pipe is heated on its external surface by the induction heater, which is switched on and off during the experimental data acquisition while molten salts are continuously circulating in its interior. These conditions are replicated, for the first time, in a two-dimensional numerical domain fully coupling the electromagnetic and thermal physics, including thermally dependent material properties of the heated pipe. Once validated against the experiments, the numerical results revealed that the volumetric nature of the induction heating shall be considered for an accurate representation of the temperature profile inside the tube. As a novelty, different equivalent surface boundary conditions are presented and, despite the Gaussian-like behavior of the induction heating on the surface of the tube, the results indicate that there exists no equivalent wall boundary condition to fully replicate the temperature profile obtained with the induction heater. The effect of independently varying experimental parameters such as the geometry of the pipe (i.e., diameter and thickness) and its distance to the induction heating system is also evaluated. Using large diameters of the tube reduces the difference between the angular temperature profile obtained using induction heating and a simplified wall boundary condition. For small wall thicknesses, the induction heating is capable of penetrating along the whole thickness of the tube, the total heat generated in the volume of the tube being exposed to the counteracting effects of the volumetric generation and the enhancement of the heat dissipation by the molten salt, as both of them increase for small thicknesses. The distance of the inductor to the pipe wall appears to maintain the volumetric characteristics of the heating and only affects the induction heating magnitude and efficiency. • Fully coupled model of induction heating of a molten salt pipe is presented. • Induction promotes a volumetric heat generation in the pipe. • No equivalent surface heating can replicate induction heating. • Effect of different pipe geometries on the induction heating was characterized. • Induction reaches the whole pipe thickness for sufficiently thin tubes.

Development and research of an induction heating system for a long pipeline

The authors proposed an induction heating system for an extended pipeline, which implements the technology of local-associated heating, using the methods of functional integration. The authors carried out a study of the technology of local-associated thermal effect on an extended pipeline. We have developed a technical solution for a system of local-associated induction heating of a long pipeline using functional integration methods. We also developed a computer model of the system in the ELCUT 6.4 software package. The authors evaluated the efficiency of the heating process and obtained the characteristics of the magnetic field of the system as a result of modeling. We have solved a thermal problem that demonstrates the efficiency of the local heating technology.

Control of a Matrix Converter for Induction Heating System

Control of a Matrix Converter for Induction Heating System

Development of Induction Heating System Ensuring Increased Heating Efficiency of the Charge Material in a Forging.

This study performs a complex analysis and review of the currently applied methods of inductively heating the charge material in hot die forging processes, as well as elaborates and verifies a more effective heating method. On this basis, a device for inductive heating using variable frequency inductors was designed and constructed, which made it possible to reduce the scale and decarburization with respect to the heater used so far. In the first place, the temperature distributions in the heater in the function of time were modeled with the use of the CEDRAT FLUX software. The aim of the research was to analyze the temperature gradient and value diversification on the surface and in the material core, as well as to determine the process stability. The following stage was designing and constructing a heater with an automatic system of loading and positioning of the charge on the exit, as well as with a possibility of working in a fully automated system adjusted to the work center. The last stage of investigations was the verification of the elaborated effective heating method on the basis of a short production series and a continuous work for the period of 8 h, both in the quantitative and qualitative aspect (reduced oxidation and decarburization as well as a gradient between the core and the surface). The obtained results confirm the effectiveness of the proposed solution referring to heating the charge material, especially in the aspect of stability and repeatability of the process, as well as a significant reduction in oxidation and decarburization of the material surface.

Induction Heating in Underwater Wet Welding-Thermal Input, Microstructure and Diffusible Hydrogen Content.

Hydrogen-assisted cracking is a major challenge in underwater wet welding of high-strength steels with a carbon equivalent larger than 0.4 wt%. In dry welding processes, post-weld heat treatment can reduce the hardness in the heat-affected zone while simultaneously lowering the diffusible hydrogen concentration in the weldment. However, common heat treatments known from atmospheric welding under dry conditions are non-applicable in the wet environment. Induction heating could make a difference since the heat is generated directly in the workpiece. In the present study, the thermal input by using a commercial induction heating system under water was characterized first. Then, the effect of an additional induction heating was examined with respect to the resulting microstructure of weldments on structural steels with different strength and composition. Moreover, the diffusible hydrogen content in weld metal was analyzed by the carrier gas hot extraction method. Post-weld induction heating could reduce the diffusible hydrogen content by −34% in 30 m simulated water depth.

Comparison of New Multilevel Inverter Topology with Conventional Topologies Used for Induction Heating System

In this article, a comparison of innovative multilevel inverter topology with standard topologies has been conducted. The proposed single phase five level inverter topology has been used for induction heating system. This suggested design generates five voltage levels with a fewer number of power switches. This reduction in number of switches decreases the switching losses and the number of driving circuits and reduce the complexity of control circuit. It also reduces the cost and size for the filter used. Analysis and comparison has been done among the conventional topologies (neutral clamped and cascade H-bridge multilevel inverters) with the proposed inverter topology. The analysis includes the total harmonic distortion THD, efficiency and overall performance of the inverter systems. The simulation and analysis have been done using MATLAB/ SIMULINK. The results show good performance for the proposed topology in comparison with the conventional topologies.

Harmonics Suppression of AC Source Current of a Single Phase Source Fed Induction Heating System

Any high frequency Induction heating system while undergoing through very high frequency switching operations, produces Electromagnetic Interference (EMI) noises or very high frequency harmonics within the system. These high frequency EMI noises conductively propagate towards the input AC source and distort the sinusoidal input AC current and make it non-sinusoidal. The desired performance from the induction heating cannot be anticipated. As such, it is inevitable to eliminate such EMI noises from the input AC source current to get the desired performance. Here, a specially designed ring type LC low pass passive filter is proposed which can accomplish to suppress these high frequency EMI noises up to satisfactory level and can restore the sinusoidal shape in the input AC source current waveform and thus improves the power quality of the AC supply for the induction heating system. The impact of the induction heating system without and with incorporating the proposed filter will be compared in this study.

ИССЛЕДОВАНИЕ ФИЛЬТРОКОМПЕНСИРУЮЩЕЙ ФУНКЦИИ МНОГОФУНКЦИОНАЛЬНОГО ИНТЕГРИРОВАННОГО ЭЛЕКТРОМАГНИТНОГО КОМПОНЕНТА В СОСТАВЕ СИСТЕМЫ ИНДУКЦИОННОГО НАГРЕВА

Relevance The need for computer simulation is due to the modes of operation of induction heating systems and the high cost of the element base. This avoids the cost of expensive components. The use of a multifunctional integrated electromagnetic component is justified by the cost of individual discrete components that make up the induction heating system, as well as by the provision of the functionality of filter compensating devices. The use of a multifunctional electromagnetic component makes it possible to achieve a reduction in the resource intensity of the circuit, its cost, and to increase the reliability of the device. Aim of research This article discusses the design of an induction heating system with the function of a filter-compensating device, made on the basis of a multifunctional integrated electromagnetic component for an induction heating system that implements the technology of locally associated heating of an extended pipeline. The main task is to determine the electrical circuit of the filter-compensating device operating as part of an induction heating system of locally associated heating and the analytical calculation of the parameters of a multifunctional integrated electromagnetic component. Research methods In this study, the following methods were used: patent review, study of scientific literature, computer simulation performed in the ELCUT 6.4 software package. Results The authors have developed a scheme of an induction heating system with the function of a filter compensating device based on a multifunctional integrated electromagnetic component for an induction heating system that implements the technology of locally associated heating of an extended pipeline using functional integration methods. A study was made of the technology of locally associated thermal impact on an extended pipeline. In the ELCUT 6.4 software package, a computer model of the system was developed, and the efficiency of the filter-compensating device during the heating process was evaluated. As a result of the simulation, the characteristics of the magnetic field of the system were obtained and the thermal problem was solved, demonstrating the effectiveness of the technology of locally associated heating.

Quasi Resonant Inverter Load Recognition Method

Induction heating (IH) technology is very popular in domestic applications because of its efficiency and safe operating properties. Resonant inverter circuits are widely used in IH systems owing to their high efficiency and soft-switching capability. Among the resonant inverters used in IH systems, the single-switch quasi-resonant inverter topology is generally preferred for low-cost and low-output-power applications. Despite the low-cost advantage of the quasi-resonant inverter, the soft-switching range is quite narrow, and it is not stable depending on the electrical parameters of the load that is desired to be heated. In other words, there is a critical relationship between the electrical characteristics of the pan, turn-on, and turn-off times, which are the control parameters of the semiconductor switch, and the safe working conditions. In addition, when the importance of closed-loop control methods is evaluated together with the selection of resonant circuit elements, it is essential to determine whether the load is suitable for heating, and to determine the electrical properties of the load to provide both reliable and efficient operating conditions. This study focuses on a new load-detection method based on circuit analysis for quasi-resonant induction hobs. After determining the load parameters, the turn-on and turn-off times of the semiconductor switch were determined to obtain the lowest possible switching loss. Therefore, the boundary conditions of the semiconductor switch are maintained within these limits. The proposed method and its advantages for the switch safe operating area were theoretically examined and proved through simulations and prototype circuits.

Analysis of the manufacturing process of a car bonnet using Compression Resin Transfer Moulding (CRTM)

Compression resin transfer moulding (CRTM) can help to reduce costs and increase the productivity of composite parts in the automotive industry. This process is suited for fast production of high quality parts, but a number of parameters must be precisely characterised and well controlled during the process. This work describes the CRTM manufacturing process of a real sports car bonnet. Resin and carbon fibre reinforcement have been characterised (viscosity, permeability), and this information has been used to perform numerical simulations to optimise the process parameters in order to reduce the cycle time. The heating cycle has also been optimised and the possible implementation of an induction heating system has been analysed. Once the process parameters have been defined, the mould has been manufactured and bonnet prototypes have been manufactured. This work has been carried out within the framework of the project ADVANCRTM.

Low-temperature induction heating of flat metal objects in a traveling electromagnetic field

The article discusses possible options for a low-temperature induction heating system (LTIHS) of flat metal products in a traveling electromagnetic field. The problem of calculating eddy currents, active and reactive powers induced in a heated flat object, as well as electromagnetic forces acting on the object moving it in a given direction, is posed and solved. A mathematical model has been developed that takes into account the dependence of the influence on the main parameters of the electromagnetic field of the following factors: geometric dimensions of the air gap between the poles of the magnetic circuit and the heated flat body; the longitudinal edge effect caused by the open circuit of the magnetic circuit of the inductor, as well as the transverse edge effect associated with the appearance of the longitudinal components of eddy currents in a heated flat object. The solution of particular problems of LTIHS in one- and two-dimensional formulation allows them to be simplified and to perform calculations for various design variants of induction heating devices with a traveling electromagnetic field, using a one-dimensional model that explicitly takes into account the features of electromagnetic processes in the systems under study.