共查询到20条相似文献,搜索用时 349 毫秒
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我公司电机铸铝转子用熔铝设备 ,是由青岛工业电炉厂生产的工频无芯感应电炉 ,由两个炉体、一个电器控制柜组成。其炉体由炉架保温层、感应线圈、铸铁坩埚、铁心等组成。在多年的生产实践中 ,最常见而最难以解决的问题是铸铁坩埚破损漏铝严重 ,造成炉体感应线圈等粘在一起而无法清理的问题。一般情况下 ,坩埚漏铝时 ,铝液都是聚集在炉体底部 ,而炉体底部是封闭的 ,随着铝液的增多 ,铝液液面逐渐升高 ,而铝液又无法跑出 ,进而渗入铁心、感应线圈 ,若不能及时发现 ,轻者使炉体、感应线圈、保温层粘结在一起 ,重者烧坏感应线圈绝缘 ,对地击穿 ,… 相似文献
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中频感应透热依据的是电磁感应、集肤效应、热传导三项原理,在一次线圈中通入交变的中频电流,引起闭合的二次线圈中磁通量变化.被加热的金属工件组成了短路的二次线圈,图1为感应加热示意图. 相似文献
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0引言 中频感应电炉因污染小、功效高而受到熔炼铸造行业的欢迎.我公司机修厂现在使用的2号800kW中频感应电炉是由西安机电研究所生产,投产以来,生产一直都很稳定.在中频电源调试期间,我们与西安机电研究所工程技术员密切合作,学到了很多的调试经验,就我们以后对设备的正常维护都非常重要. 相似文献
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请问晶闸管中频感应熔炼电源并联逆变器中的串并联负载电路与单一并联负载电路在功能上有什么不同? 相似文献
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An unusual ``incubation' period is encountered at the beginning stages of medium frequency (3 kHz) induction heating of unsintered, low alloy, steel powder metal compacts. This incubation period is characterized by poor load coupling to the induction coil and consequently, very slow and inefficient heating. An unusually high material resistivity has been isolated as the cause of this incubation period. A technique is described for eliminating the incubation problem by preheating the material contained within the reference depth to 4000 F by either radiant heating or radio frequency induction heating. This preheating results in more than an order of magnitude reduction in the resistivity of the preheated material and a considerable net energy savings during subsequent medium frequency heating to the sintering temperature. A mechanism is also postulated for the cause of the unusually high compact resistivity and its reduction via preheating. 相似文献
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H.M. Unver M.T. Aydemir V. Celik 《Power Engineer (see also Power Engineering Journal)》2005,19(3):36-39
The induction furnace has been used in a massive range of applications from heating, melting and welding to shrink-fitting, forming, soldering and even plasma physics. Furnaces operate at frequencies between 10 Hz to 60 MHz, and as a result, different power supplies - operating at different frequencies - have also been developed. Induction steel heating furnaces (ISHF) have several advantages in practical applications. However, when a material is heated within an ISHF, its resistivity and magnetic permeability fluctuate, which proves detrimental to the control of power within the furnace. One way to improve power control within an ISHF is to use a programmable logic controller (PLC). Indeed, modern PLCs are modular, affordable, have large memory capacities, and also have special functions such as pulse wave modulation (PWM) and data communication. Using a PLC not only eases position, temperature and pressure control within the ISHF, but also provides overvoltage and overcurrent protection. A new PLC control system design allows heating to take place at constant power while maintaining a steady resonance frequency. The article introduces the system. 相似文献
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传统电机是机-电能量转换,损耗与温升是电机设计时需要削弱和避免的问题。该文从传统电机损耗与温升出发,提出了用于加热的零机械能输出感应电机。利用绕组所产生的径向磁场在实心结构的定子和转子铁心中感应产生涡流,将输入的电能全部转化为热能,具有定子、转子双边加热的特点。其独特的双边加热效果可解决挤塑类设备旋转螺杆加热瓶颈问题。建立了系统等效模型,给出了电磁功率解析表达式,采用有限元法分析了系统涡流分布与铁心端部效应。对样机进行加热实验,结果证明该种电机与传统线圈缠绕式电磁加热相比,具有节能高效、预热时间短、径向温差小等优点。 相似文献
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清江大通机电公司以节能降耗为目的,进行设备更新和节电技术改造。通过生产设备工艺系统改造、电加热节能改造、润滑冷却系统改造、电动机变频调速改造等措施,提高了电能使用效率,降低了产品单耗,实现了漆包线生产企业的节约化生产。 相似文献
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目前,感应加热电源技术主要朝着大功率、高频率和智能化控制技术的方向发展。然而,随着逆变开关频率的提高,功率器件的开关损耗随之增加。具有高临界雪崩击穿电场强度、高热导率、小介电常数等突出优点的宽禁带半导体材料SiC MOSFET的应用为这一问题的解决提供了理想的方案。本文详细研究了感应加热电源逆变器的设计、SiC MOSFET器件的驱动电路以及电源的功率扩展等问题;开发出了频率超过800 kHz,单逆变桥功率超过50k W的新型感应加热电源;通过并桥处理,电源单机容量可达200 kW,在一定程度上填补了将新型SiC MOSFET器件应用于感应加热领域的空白。 相似文献
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电站1#、2#煤粉炉电除尘器电源系统采用的是传统工频电源供电方式,除尘效率低,提出了使用高频电源来提高电除尘除尘效率并达到节能效果的可行性分析及对策,大幅度提高除尘效率,达到节能降耗目的。 相似文献
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This paper presents a 4 kW, 450 kHz voltage-source inverter with a series resonant circuit for induction melting applications, which is characterized by the power control based on pulse density modulation (PDM). The pulse-density-modulated inverter makes an induction melting system simple and compact, thus leading to higher efficiency. A modulation strategy is proposed to realize the induction melting system capable of operation at the frequency and power level of interest. Some interesting experimental results are shown to verify the validity of the concept 相似文献
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针对IGBT中频电源中逆变电路这一核心,提出了一种基于87C196MC单片机中频电源控制电路。用87C196MC单片机通过汇编语言程序设计,可方便地形成3对互补具有死区时间相位互差120°的SPWM波形,产生的脉冲信号(SPWM)控制功率器件IGBT的开关时间,实现对中频电源的控制。分析和实验结果表明,此系统效率高,噪声小,体积小,使用方便,工作可靠。基于以上的优点,单片机控制的IGBT的中频电源的应用范围更加广泛,成为用于加热淬火的首选设备。 相似文献