课程文献中心 更多>>

关键词： 采煤机   变频器   漏电闭锁  

摘要： 目前国内的电牵引采煤机在高压负载回路里都设有无载(送电前)漏电闭锁装置,但是低压侧380/460 V变频器驱动电路和牵引电机线路缺乏有效的漏电闭锁装置,可能会导致采煤机变频器供电线路、牵引电机线路漏电和变频器损坏等故障。根据变频器回路的电气特点,设计了一种变频器供电回路的无载和有载漏电检测系统,有效实现了变频器在送电前后的漏电检测,并在生产实际中验证了该设计的高效和准确。

关键词： 半挂液罐车   弯道路段   液体晃动   侧翻事故防控   最优控制  

摘要： 为降低半挂液罐车驶过弯道路段过程中的侧翻事故风险,提出了基于最优控制的半挂液罐车弯道安全车速优化控制方法。该控制方法以侧翻事故防控为优先目标,以高效通行为辅助目标,帮助半挂液罐车在驶向弯道时提前获得无横向失稳隐患的最优车速控制方案,实现“预防式”的车辆主动安全控制。同时为提高控制方案有效性,利用正弦波动方程拟合罐内液体纵向转移过程,结合基于改进准静态法的罐内液体横向偏移规律,构建了具有纵横双维度描述能力的罐内液体晃动模型,提高了最优控制问题成本函数中半挂液罐车横向稳态表征指标的准确性。仿真结果表明:受控半挂液罐车驶过弯道过程中的瞬时横向载荷转移率始终处于[-0.7,0.7]的安全范围内;不同弯道半径下车辆瞬时横向载荷转移率均有下降,且在弯道半径61 m时降幅最大;受控半挂液罐车最大瞬时横向载荷转移率最大降幅达到0.07;车速控制对道路通行效率的负面影响较小。该控制方法帮助半挂液罐车避免侧翻事故,适用于多种不同半径的弯道路段。

关键词： 提升机   电气传动   变频器   设备冗余  

摘要： 金川集团股份有限公司三矿区50行主井提升机传动系统采用中压交直交变频驱动控制方式。主传动变频器使用ABB公司的ACS6000中压交直交变频器,配套4500KW低速直联交流同步电机。原传动系统只有一套变频器,通过改造,实现了主井提升机主传动装置及配套设备的冗余控制,提高了系统的保障能力。

关键词： IGBT   cervix cancer   HRCTV  

摘要： 2554

关键词： Freewheeling diode (FWD) chip   insulated gate bipolar transistor (IGBT) chip   IGBT module   thermal coupling   two-branch coupling Cauer model  

摘要： Insulated gate bipolar transistor (IGBT) modules are often operated under high switching frequency and large electromagnetic inertia, and the internal freewheeling diode (FWD) chip generates non-negligible heat due to its freewheeling effect. In the conventional Cauer model, only the heat generated by the IGBT chip itself is considered, and the thermal coupling effect between the IGBT chip and the FWD chip is ignored, which leads to a large calculation error. Therefore, this article focuses on the thermal coupling effect between the IGBT chip and the FWD chip inside the module, and proposes the basis for determining the existence of thermal coupling and the method for determining the position of thermal coupling. Based on the conventional Cauer model, a two-branch coupling Cauer model for calculating the junction temperature of the IGBT chip and the FWD chip is established, and the extraction method of model parameters is given. Finally, a single-phase half-bridge inverter circuit is selected, and it is experimentally verified that the improved Cauer model has higher junction temperature calculation accuracy than the conventional Cauer model.

关键词： Coils   Legged locomotion   Switches   Inverters   Topology   Tokamak devices   Plasmas   Divertor tokamak test (DTT)   IGBT   interleaved strategy   non-axisymmetric coil power supply   single-phase inverter   unfolder switch  

摘要： This article deals with a single-phase inverter topology evaluation for a non-axisymmetric in-vessel coil system in a tokamak. An IGBT-based power converter topology is investigated to supply the magnetic system composed of several independent coils. The dc-ac converter topology used for a single coil consists of a single-phase inverter with an interleaved leg and unfolding switching strategy. The converter operation and control investigation are carried out with a Hardware-in-the-Loop (HIL) approach. In the paper, the main control design requests and the issues of this application are explored. Then, the effectiveness of the proposed approach is validated by the HIL. Furthermore, the selection criteria for the power switches are discussed.

关键词： A single insulated gate bipolar transistor (IGBT) open-circuit fault   fault location and tolerance   power electronic transformers (PET)  

摘要： Power electronic transformers (PETs) contains numerous power electronic modules and multiple power conversion stages, potentially leading to an increased failure rate. The complex impacts of insulated gate bipolar transistor (IGBT) faults and strong coupling between power conversion stages make it difficult to accurately locate faults using traditional methods designed for single stage converters. To address this challenge, a simple method to locate and tolerate a single IGBT open-circuit fault of PETs is proposed, by integrating and synthesizing the dynamic characteristics of measurement signals of PET and key node information of the controller loops. The proposed method is easy to implement without using additional sensors, and it can transfer between normal operation and fault tolerant operation without noticeable inrush current or voltage. Experimental tests validate the effectiveness of the proposed approach.

关键词： gate driver   IGBT   protection algorithms   overcurrent protection   overvoltage protection  

摘要： Featured Application The proposed solution for the high-power IGBT driver can be used as a reference for the design of similar intelligent gate drives, improving the reliability of power electronic converters in traction, industrial, and renewable energy *** High-power IGBTs are used in power electronic converters in a variety of applications: traction drives, renewable power converters, mining equipment, oil and water pumping, and so on. To control a transistor, a special gate driver board is required. This board converts the logical control signal into the appropriate voltage values necessary to turn the resistor on and off. Gate drivers can perform the protection functions of IGBTs using hardware and algorithmic approaches. Application-specific integrated circuits are often used in driver solutions to implement control and protection. The development of an application-specific integrated circuit is a time-consuming and expensive procedure, which increases the cost of the driver. This paper describes the control and protection algorithms implemented in an intelligent IGBT driver based on a low-cost microcontroller. The use of the microcontroller makes the gate driver design more flexible and allows for the accurate tuning of the protection thresholds. The gate driver protects the IGBT from short-circuiting, overcurrent, and overvoltage, monitors the voltage supply, and controls the switch on and switch off processes in the transistor. The performance of the protection algorithms was tested experimentally using a specialized test bench.

关键词： Cryogenics   Gate drivers   Integrated circuits   Power supplies   Capacitors   Voltage control   Superconducting magnets   Cryogenic electronics   gate driver   IGBT   MOSFET   propulsion  

摘要： Aiming to increase the power density of electrical systems and realize all-electric aircraft, research has been focused on immersing power electronics at cryogenic temperatures as they tend to have lower conduction and switching losses. To ensure proper switching of semiconductor devices at cryogenic temperature, their gate driver circuits should ideally be placed in close physical proximity and therefore in the same environment. Although some commercial off-the-shelf gate drivers have been tested at cryogenic temperatures, in this article we present a bespoke magnetically isolated gate driver for cryogenic temperatures. Experiments with the circuit immersed in liquid nitrogen verify the proposals of the article.

关键词： Recovery performance   Reverse-conducting insulated gate bipolar   transistor (RC IGBT)   Snapback-free   Turn-off loss  

摘要： A novel fast-switching P-poly trench collector reverse-conducting insulated gate bipolar transistor (RC-IGBT) with different N-buffer position (DBP) is proposed and investigated. Firstly, the N-buffer on P-poly TrenchCollector (TC) not on P+ and N+ collector will unaffected realize snapback-free with and without interface charge exist in the forward conduction. Secondly, N-buffer on TC can keep the fast extraction channel to the N+ collector open all the time, so that the ultralow turn-off loss (EOFF) can be achieved in IGBT mode, and the reverse recovery charge (Qrr) can be reduced in diode mode. Thirdly, N-buffer on TC makes the electric field distribution more uniform during forward blocking, thus further improving the breakdown voltage (BV). Fourth, N-buffer on TC can also provide more electrons to reduce forward peak recovery voltage (VFRM) during diode forward recovery mode. Compared with PNTC RC-IGBT, the proposed RC-IGBT enjoys lager breakdown voltage, and can reduce VFRM by 83%, Qrr by 27%, and the EOFF by 36%.