Bunker Oil C Heating Using Induction Heating

This chapter deals with some specific applications of induction and direct resistance heating, that have been investigated also by the authors of this book. When available, analytical solutions for these ‘special’ applications are provided. Section 4.1 is about the resistance heating of ferromagnetic workpieces of rectangular cross-section, Sect. 4.2 describes the direct resistance heating of bended conductors. The transverse flux heating is a technology that is applied for treating thin slabs and stripes with high electrical efficiency and is the topic of the Sect. 4.3. Planar coils, often named pancake inductors, are described in the Sect. 4.4, while the effects due to the finite length of inductor are discussed in Sect. 4.5. Induction hardening of workpieces of complex geometry is one of the most important applications of induction heating, single and dual frequency processes for contour hardening are presented in Sect. 4.6. The innovative process of through heating by rotating a nonferrous billet inside a DC field produced by superconductive coils is detailed in Sect. 4.7, while in Sect. 4.8 the induction heating is produced by rotation of permanent magnets. Section 4.9 deals with the induction heating of hollow workpieces heated by internal inductors and Sect. 4.10 describes the forces acting in induction heating applications.

Prevalent converters for induction heating (IH) applications employ two-stage conversion for generating high-frequency magnetic field, namely, AC to DC and then DC to high-frequency AC (HFAC). This research embarks upon a direct conversion of utility AC to high frequency AC with the design of a single-phase matrix converter (SPMC) as a resonant converter using a modified switching technique for IH application. The efficacy of the proposed approach is validated through different attributes such as unity power factor, sinusoidal input current and low total harmonic distortion (THD). The developed prototype-embedded system has high pragmatic deployment potential owing to its cost effectiveness using Arduino mega 2560 and high voltage/current as well as low switching time IXRH40N120 insulated-gate bipolar transistor (IGBT). Different results of the prototype-embedded system for IH application have been verified using Matlab Simulink environment to corroborate its efficacy.

Plastic pyrolysis over HZSM-5 zeolite and fluid catalytic cracking catalyst under ultra-fast heating

<div class="htmlview paragraph"><b>INDUCTION heating is a process or method by which metal parts are heated by simply placing them in an alternating magnetic field</b>.</div> <div class="htmlview paragraph"><b>The action is that of the transformer, whereby electrical energy is transferred or passed over to another isolated electric or secondary circuit by means of the magnetic field; thus, no physical attachments or electrical contacts are necessary to have electrical currents, which are dissipated as heat, flow in the parts to be processed</b>.</div> <div class="htmlview paragraph"><b>The strength and frequency of the alternating magnetic field can be selected to produce any desired rate of heating and ultimate temperature</b>.</div> <div class="htmlview paragraph"><b>A circuit can be set up to dry lacquer at 160 deg. fahr. on thin sheet-metal parts or to melt in record time immense steel ingots</b>.</div> <div class="htmlview paragraph"><b>Induction heating is now commercially applied in automotive production to many processes, and these are specified</b>.</div> <div class="htmlview paragraph"><b>The development of lower cost electrical apparatus suitable for induction heating has greatly stimulated its commercial use, and the field of application will rapidly expand as the many values of the process become better known</b>.</div>

This paper investigates the evolution of temperature and stress during induction heating local postweld heat treatment (PWHT) of ultra-thick pressure vessels (with a thickness typically exceeding 300 mm) through electromagnetic-thermo-mechanical coupling simulations and experimental validation, aiming to develop an effective heat treatment method for ultralarge equipment. The effects of various inductive heating parameters including the cable winding width, the number of turns, the spacing, the winding method, the current density, and the current frequency on the temperature uniformity during the heat treatment holding time are studied. The results indicate that the maximum temperature difference is directly proportional to current density, but inversely proportional to frequency, winding width, and the number of turns. After local PWHT, the residual stress on the outer surface of backward-oriented pressure vessels can be effectively reduced, but the stress relief on the inner wall is relatively small. Furthermore, the influence of heated bandwidth on the reduction of residual stress is considered. If reducing residual stress on the inner wall is considered, the width of the heated band should exceed 3Rt. If aforementioned width cannot be achieved, the local PWHT by primary plus secondary heating method can be used to further reduce the residual stress. This research sheds light on the application of inductive heating in ultralarge pressure vessels.

This paper presents a new single-stage utility frequency ac (UFAC)-high frequency ac(HFAC) resonant power converter for high frequency induction heating(IH) applications. The newly-proposed ac-ac converter features a boost converter and full-bridge HF resonant inverter integrated circuit (Boost-Full-Bridge BFB) with a source voltage sensorless control scheme. The experimental results of a 3.0kW–40kHz prototype are demonstrated on zero voltage soft switching (ZVS) operations and steady-state characteristics based on the phase shift pulse-width-modulation (PS-PWM) power regulation, then the validity of the proposed ac-ac converter is revealed from a practical point of view.

Nowadays Induction heating (IH) technology is the heating technology of choice in modern domestic applications due to its high efficiency, fast heating, safety, and cleanness. With the development and improvement of power electronic devices, the technology of making this heating technology is more efficient and cost-effective. This paper presents a half-bridge series resonant inverter for induction heating (IH) application that works in two operating modes to improve the efficiency of this application in a wide power range. In this structure, to control the power output, changing the switching frequency is used for high power range, and pulse width modulation (PWM) is used for low power range, so that reduces the losses and increases the efficiency of the converter in all range power. The operating modes of the converter can be changed by changing the snubber and resonant capacitors through electromechanical switches. In order to show the feasibility, the simulated and experimental results for an IH rated on 1kw are presented.

Single-ended resonant inverter topology is widely used in domestic induction heating (IH) application due to its concise structure and cost effectiveness. Whereas high resonant voltage caused by the energy transfer between load inductor and resonant capacitor in the IH system may negatively affect the operation of system and long-term reliability. Generally, 1200 V rating IGBT is popularly used for single-ended IH cookers. However, abnormal conditions of AC supply suddenly increases the resonant voltage thereby IGBT can be destructed. Resonant voltage limiting technology is proposed by restricting the maximum current flow to the load inductor in order to relieve the voltage stress across the IGBT. The effectiveness of the proposed method is verified for AC supply distortion by using 1.35 kW single-ended IH system.

Cold spray is an additive manufacturing process increasingly used for repair and restoration of damaged components. A common problem with the technology is the high level of porosity in the as-sprayed coatings. Effort has been made in the past to reduce the porosity level by post-processing methods such as heat treatment in vacuum furnace. However, the conventional heat treatment is a slow process which typically takes a few hours. The prolonged heating and cooling cycles reduce productivity and could cause some adverse effects on the components. The current research aimed to develop a rapid technique for post-processing of cold spray coatings. Cold spray was carried out to coat multiple layers of CoNiCrAlY powders onto Inconel 718 substrate. The coatings were then post-processed by induction heating at 800, 900, 1000 and 1100 °C. The experimental results show that induction heating reduced the porosity level significantly in a short period of merely 10 min. The effectiveness of induction heating is attributed to the preferential electrical resistance heating of regions with pores. The study demonstrates the potential application of induction heating for rapid post-processing of cold spray coatings.

Flexible-surface induction heating appliances present an increased number of coils, widening the variety of pot inductor systems to be powered simultaneously. Moreover, the properties of these systems vary with the mains voltage, increasing the challenge to achieve proper mains current consumption. This paper proposes and analyzes two fixed-frequency asymmetrical modulations for improved power factor correction while avoiding intermodulation acoustical noise, critical for domestic induction heating applications.

We analyze the forces exerted on the pots used as loads of induction heating appliances. These forces depend on the parameters of the induction heating system and also depend on the arrangement and geometry of the application. Forces can be calculated by means of finite element tools but not straightforwardly because the materials of pot combine both eddy currents and ferromagnetism. For this reason, the Maxwell’s stress tensor is used. The exerted force causes the change of the weight of the pot when power is supplied, with respect to the off state. The change of weight is theoretically analyzed and experimentally measured. As it is also shown, the change of weight is also related with the electromagnetic properties of materials and the operating frequency, and this fact can be used to characterize the induction loads. Calculations are validated by means of an experimental setup arranged by means of load cells.

Induction heating is a popular and powerful technique to provide very high temperature for applications such as steel melting, brazing, and surface hardening. This paper presents full bridge resonant inverter for nonmetal induction heating application including six components: transformer, full bridge rectifier, full bridge inverter, resonant tank, high frequency transformer, and non-ferrous metal smelting. The experimental results provide significantly a power supplying of heat. The diameter of the non-ferrous metal melting is 2.5 centimeters and the height is 5.5 centimeters. The 50-gram lead is heated with the ambient temperature of 349°C in 60 seconds, causing completed melting. It generates the output power of heat appropriately 1.46 kilowatts and provides high efficiency with 88% at full power.

The proposed paper deals with the design and analysis of RFI and EMI suppressor for high frequency Induction Heating equipment using filters. The simulation has been done in PSIM software. The harmonics that are injected because of the high frequency switching have been a major problem in induction heating applications. These harmonics can be reduced by the connection of a low pass filter between the ac supply and the induction heating equipment. The design should be in accordance with the harmonic standards that play a very crucial role in deciding the amount of current harmonics that is allowed to flow back to the supply side. In this present work, a Semi Active Filter has been proposed that has much better harmonic attenuation ability than the existing passive filters. The THD of input current has been compared to show that the former is able to maintain much better power quality than the latter. Moreover, both of them are also compared to the system without an LPF to show the necessity and importance of low pass filters in Induction Heating Equipment.

In this paper, a novel type auxiliary active resonant capacitor snubber assisted zero current soft switching pulse modulation single-ended push pull (SEPP) series load resonant inverter with two auxiliary resonant lossless inductor snubbers is proposed for consumer high-frequency induction heating (IH) appliances. Its operating principle in steady state is described by using each mode equivalent circuits. The new multi resonant high-frequency inverter can regulate its output power under a condition of a constant frequency zero current soft switching (ZCS) commutation principle on the basis of asymmetrical PWM control scheme. The consumer brand-new IH products using proposed ZCS-PWM series load resonant SEPP high-frequency inverter is evaluated and discussed as compared with conventional high-frequency inverter on the basis of experimental results. In order to extend ZCS operation ranges under a low power setting PWM, the pulse density modulation (PDM) strategy is demonstrated for high frequency multi resonant inverter. Its practical effectiveness is substantially proved from an application point of view

This paper presents a new prototype of a single-stage ac-ac converter with Silicon-Carbide (SiC)-MOSFET / SiC-SBD integrated power module for induction heating (IH) applications. Switching and conduction power losses are effectively reduced by virtue of the 1.2kV-120 A All-SiC power module under the condition of zero voltage soft-switching (ZVS), as compared to the counterpart solution using a Si-IGBT / Si-PNDiode power module. The performances of the new prototype are evaluated by experiment, thereby demonstrating the advantageous properties such as high-efficiency and low switching noise due to the wide band-gap power module.