滤波装置中晶闸管移相触发电路的设计

针对滤波补偿装置中要求电容器投切速度快,无冲击电流、电压的问题,设计了一种基于晶闸管移相触发的电路。该电路实现了快速无冲击投切,设计简单,能很好地解决过零触发电路经常遇到的过零检测混乱而导致的误触发,以及触发需等待电容器放电,有一定延迟的问题。通过现场实验测试分析说明,此移相触发电路的良好实用性。     

中频电炉维修技术探讨

中频电炉的故障现象分为完全不能启动和启动后不能正常工作两大类。而这些故障一般都是由缺相、整流晶闸管和快速晶闸管烧坏、中频电容器击穿失效、水冷电缆断路、电抗器故障和感应线圈故障及控制电路板故障引起的。笔者就以上故障产生的原因进行了分析,并提出排除这些故障的措施。     

矿用局扇节能起动器触发电路的研制

介绍一种用于煤矿局扇节能起动器内的晶闸管桥臂模块触发电路,提出了用厚膜集成触发器加少量相关元件组成三相移相触发电路的设计要点.实际运行表明,该触发电路结构简单,抗干扰能力强,运行可靠.     

150kW交流稳压电源系统

电网电压的波动将严重影响设备的正常工作，设计了一套大功率单相交流稳压电源，通过单片杌对晶闸管的控制来实现网压补偿。该电源由单片机系统、主电力电路、晶闸管触发电路、检测和保护电路等组成。实践表明该电源工作可靠，稳压效果良好。研制的大功率强触发式晶闸管触发电路结构紧凑，成本低，控制性能好，可广泛用于各种晶闸管系统。     

基于DSP的晶闸管数字式触发电路的设计与研究

触发电路是晶闸管变流技术的重要组成部分.采用DSP技术,来实现触发器的移相及脉冲形成,辅以同步整形和功率放大等模拟环节,构建出一种新的数字式的触发器.介绍其软件流程与控制过程,以及相关的电路设计.     

Investigation of high-voltage integral pulse thyristors in single-pulse and pulse-train modes

The results of studying the switching capabilities of recently developed high-voltage integral pulse thyristors (HIPTs) with a working area of 0.45 cm² and an operating voltage of 3 kV are presented. A silicon chip of a thyristor consists of a large number of microthyristor cells that are enabled strictly synchronously with a control-current pulse, thus providing low switching energy losses and allowing a current of up to 8 kA at a pulse duration of 1.5 μs to be switched within 500 ns in a single-pulse mode. The HIPT switching-off time is several microseconds when, after a power-current pulse terminates, a field-effect transistor with a low (tens of milliohms) channel resistance closes the emitter–base circuit. The low switching energy loss and the short switching-off time made it possible to use HIPTs in the mode of switching current pulses with an amplitude of 500 А at a frequency of 50 kHz.     

High-current pulse switching by thyristors triggered in the impact-ionization wave mode

The operation of a thyristor switch triggered in the impact-ionization wave mode was investigated. The switch contained two series-connected Т253-800-24 thyristors of the tablet design with a semiconductor- structure diameter of 56 mm. When a triggering pulse is applied to the switch at a voltage rise rate dU/dt of more than 1 kV/ns, the transition time of the thyristors to the conducting state was shorter than 1 ns. It was shown that the maximum amplitude of the no-failure current increases with an increase in dU/dt at the triggering stage. The possible mechanism of the influence of the dU/dt value on the thyristor breakdown current is discussed. In the safe operating mode at dU/dt = 6 kV/ns (3 kV/ns per single thyristor), the switch discharged a storage capacitor with a capacitance of 1 mF, which was charged to a voltage of 5 kV, through a resistive load of 18 mΩ. The following results were obtained: the discharge-current amplitude was 200 kA, the initial current rise rate was 58 kA/μs, the pulse duration (FWHM) was 25 μs, and the switching efficiency of 0.97.     

异步电动机软起动器可靠触发区间的分析和确定

异步电动机在软起动过程中由于自身阻抗角的变化,导致主电路中晶闸管的触发角、电流持续角、晶闸管反向导通角等变化都是一个动态的过程,并且经常导致在软起动过程中不可靠触发。文章在详细分析了这种不可靠的原因的基础上,提出了一种有效的措施,实践证明这种方法是可行的,并且具有很强的实用价值。     

三相异步电动机软启动器设计

为了解决由于三相异步电动机启动电流大,对电机造成损坏的问题,采用了80C196KC单片机及功率器件晶闸管为核心,完成了三相异步电动机软启动器的系统设计。采用模块化设计思想,利用16位单片机80C196KC实现了电压斜坡启动、限流启动、软停车等算法,通过改变晶闸管的触发角来实现对电机定子两端的电压调节,解决了电动机启动时对电网和机械设备的冲击,延长了供电设备的寿命,同时能够实现软停车、故障保护、节能等功能。     

数字式晶闸管双环直流调速系统设计

采用单片机控制的数字式晶闸管直流调速系统,能使调速系统达到较高的控制精度,具有较好工程实用价值,通用性强,易于扩展,开发成本较低,周期较短等优点。本文从单片机硬件电路设计和程序设计方面介绍了数字式晶闸管双环直流调速系统的设计过程。本系统调速范围大、电流和转速超调量低、过渡过程时间和动态恢复时间短、启动平稳、可实现无静差度调速。     

晶闸管触发器技术的新进展

本文回顾了晶闸管触发器技术的发展历程,介绍了其发展现状,预测了其发展趋势.     

用于电弧发射光谱的数字化自动引弧电路设计

转盘电极发射光谱分析技术在油液成分检测中有重要应用,研究表明,电弧光源的稳定性对光谱分析的结果有重要影响,传统的电弧发生器多使用火花放电器作为引弧电路的核心器件,在油液成分分析中引弧的稳定性和可靠性难以保证.文章提出了一种用于电弧光源激发的数字化自动引弧电路,建立了高频引弧电路拓扑结构模型,使用双路可控硅代替火花放电器...     

The error analysis of digital measurements of electrical power

Digital methods of electrical power measurements with non-sinusoidal current have become more important owing to the growing application of thyristor control. The estimation of errors by the sampling methods of measurement is complicated on account of the wide and often difficult to define frequency voltage and current spectrum. Two possible methods of error estimation are described in this paper; partly for measurement in an AC circuit with thyristor control, partly for measurement on pulse-controlled induction motors.     

基于变结构模糊控制器的钢轨闪光焊电源的设计

针对钢轨焊接的电压控制要求,研制了钢轨闪光焊稳压调压电源系统。提出了变结构的模糊控制算法,设计了以大功率晶闸管为核心的调压主电路,通过对晶闸管控制角的变结构模糊控制,实现了对电网电压的稳压处理和焊接工艺要求的电压自动调节功能,提高了焊接质量。为生产过程工艺参数调节提供了一种新思路。     

电动汽车车载锂电池分段充电策略研究

为了实现电动汽车（EV）车载锂电池快速充、放电,研究了电动汽车锂电池分段充电策略,给出了充电拓扑图。通过监控电池端电压和电流,采用了恒流、恒压和涓流3种充电方式结合的方法,控制功率变换器对电池进行智能充电。实验结果表明,利用分段充电方法可以在30min内使电池端压达到额定值,并通过恒压充电使电池迅速得以充满。该研究为提高车载电池充电效率、缩短充电时间和保证充电安全奠定了基础。     

An opto-isolator based linearization technique of a typical thyristor driven pump

A thyristor driven pump is operated by varying the DC input signal in the firing circuit of thyristor drive. This operation suffers from difficulties due to the nonlinear relation between thyristor output and DC input. In the present paper, an opto-isolator based linearization technique of a typical thyristor driven pump has been proposed. The design, fabrication and the necessary circuit diagram along with theoretical explanations of the resultant output has been described. The operation of the linearized thyristor driven pump has been studied experimentally and the experimental data before and after linearization are reported. The characteristic graphs are found to have very good linearity.     

比例电磁铁推拉储能式PWM功放电路

针对传统脉冲宽度调制(Pulse Width Modulation,PWM)功放电路难以满足大功率高频响比例电磁铁线圈快速充放电要求的问题,提出一种基于推拉储能原理的PWM功放电路。在比例电磁铁功放电路中设置储能模块,当线圈需要快速充电时,储能模块释放能量,补充供电电源电流输出;当线圈需要快速放电时,储能模块充电吸收能量,从而缩短线圈的充放电时间。针对功率79 W、额定电流3.3 A的某比例电磁铁线圈进行仿真分析和实验,研究表明:相比传统的反接卸荷式功放电路,该推拉储能式PWM功放电路充电时间缩短24%,放电时间缩短45%,显著提高了大功率比例电磁铁的响应速度。     

新型电流型PWM整流器控制技术的研究

研究了一种新的具有PWM调制功能的电流型整流器（CSR）的拓扑结构。分析了该电路的工作原理,并对其两种控制技术：正弦脉宽调制（SPWM）技术与空间矢量脉宽调制（SVPWM）技术进行研究。这种拓扑结构结合了传统的三相相控整流器和直流Buck斩波器的优点,实现了单位功率因数。降低了电流谐波含量。     

利用交流升压方法抑制弧焊逆变电源的输入电流谐波

传统的逆变焊接电源的输入电流含有丰富的谐波分量。将大功率谐波抑制技术引入焊接逆变电源,首次提出一种交流压方式的三相功率因数校正电路。这种电路将升压电感放在整流器的交流侧,与3个星形接法的双向功率开关一起构成交流升压电路。对交流升压方式的三相功率因数校正电路进行了谐波抑制性能的理论分析,并通过计算机仿真和硬件试验,表明这种电路很容易实现总谐波畸变率小于5%的谐波抑制效果。     

PCI-9846高速数字化仪在电火花放电特性测试中的应用

针对电火花放电间隙状态变化特性的检测与分析等问题,利用凌华PCI-9846四通道高速数字化仪建立了测量系统,讨论了电火花加工放电间隙放电特性测量方案,测量了不同加工状态下放电间隙两端的电压波形和电流波形,分析了空载、正常火花放电、过渡电弧放电和短路等不同加工状态下的电压波形特征及其特征参数。研究结果表明,正常火花放电、过渡电弧放电和短路等不同加工状态下间隙电压的阈值范围不同,且与加工电流有关;在设计伺服控制器时,应根据电源电压、加工电流、工件材料等来动态修正电压阈值。