ICL8001G可控碴调光LED驱动电路与应用

LED照明具有发光效率高、节能等一系列优点,目前得到了广泛的应用。由于LED可控硅调光具有使用方便、便于实现和使用范围广等一系列优点,世界上一些半导体集成电路生产制造公司纷纷推出有关LED可控硅调光控制集成电路。下面介绍由英飞凌（Infineon）公司新推出的LED可控硅（TRAIC）调光控制集成电路ICLS001G的工作原理与典型应用。     

PERFORMANCE ANALYSIS OF THE REPULSION MOTOR CONTROLLED VIA ROTOR TRIAC

ABSTRACT

This paper investigates the solid state speed control of a repulsion motor using a triac in the rotor circuit. The speed control is accomplished by varying the triac firing angle. In addition, this paper investigates the harmonic contents of the rotor current, stator current and rotor voltage The waveforms of these variables were generated and then analyzed numerically for their harmonic content using a Fouries Series Subroutine. The results were validated by comparison with obtained experimental results. More over, the harmonics generated using this type of speed control are compared with those generated when the motor is controlled via a triac in the stator cicuit.     

Solid-state speed control of the repulsion motor

This paper investigates the solid-state speed control of the repulsion motor by placing a triac in either the stator winding of the motor or the rotor winding of the motor. The speed is changed by varying the firing angle of the triac. This method of control replaces the slow, mechanical brush shifting lever with a fast, electronically controlled triac, which controls the speed without shifting the brushes, thus allowing the brushes to be fixed at a position of maximum starting torque.     

LED的调光与有关问题

LED调光可以进一步提高LED的节能效果,而LED的可控硅相控调光具有易于实现和使用方便等一系列优点,文章介绍LED可控硅相控调光的工作原理、特点和应用时需注意的有关问题。     

单相电容电机采用双向晶闸管开关电容的运行研究

提出一种运用双向晶闸管电路改变单相电容电机启动与运行电容的方法。通过晶闸管移相控制，使单相电容电机的副相电容值得以调节，从而可以在不采用离心开关的条件下实现启动与运行电容的切换，并可在不同工况时，使电机运行于相应的电容状态下。     

Reliability Testing of Triacs

A laboratory testing program which was conducted on triacs used in a prototype all-solid-state household dishwasher is described. This testing program was deemed necessary after an inordinately high number of failures of the triacs were encountered in field testing, even though the triacs were being operated well within their published specifications. The operation of triacs, the specific appliance application, and a comparative triac testing plan are described. The test results which led to the selection of a triac which met the high-reliability criteria are given, as well as some specific recommendations for the use of triacs in appliance applications.     

A New Triac Trigger to Optimize Consumer Phase Controls

The phase control methods of regulating ac power to consumer products is quite common. Households contain these circuits in diverse places from wall lamp dimmers to dad's variable speed electric drill and mom's electric blender. Common to all these controls is the triac, semiconductor ac switch, and the associated trigger circuit which provides the ``brains' of the control. The trigger, or ``brain', portion of the phase control circuit commonly utilizes a resistor capacitor network which, in combination with a voltage thresholds switch device, provides a time delay between the beginning of each half-cycle and the time the triac is triggered, i.e., shortens the portion of time power is supplied the appliance. This time delay is programmed by the resistor value, lower resistor values allowing the capacitor to charge faster, and reach the voltage threshold faster, which triggers the triac earlier in the half-cycle and applies power to the appliance for a greater portion of the half-cycle.     

WELDING TRANSFORMER CONTROL BY THE ELECTRONIC CONTROL OF LEAKAGE FLUX

ABSTRACT

In this paper, the triac is used to control the welding transformer leakage reactances and thus the welding currents. This new method keeps the input and output currents and voltages in sinusoidal wave forms.

The triac is connected across the terminals of a coil wound on a fixed limb magnetic shunt. A simple triggering circuit is used to control the current of the triac and thus the current of magnetic shunt coil. This leads to variation of welding transformer leakage flux, leakage reactances and thus a variation of welding current.

The distortion due to the triac is only affecting the leakage flux of the welding transformer. The leakage flux is very small (compared with main flux) and most of it passes in the transformer window. Then, no harmonic pollution in the bus–bar or in the welding transformer. Thus, high operating efficiency is obtained.

This new method can be used with single or three phase are welding transformer. In this work, a three phase multi–operator welding transformer is experimentally checked with the new system. The recorded wave forms support the system advantages. Performance characteristics are experimentally measured and give adequate results.     

容性负载可控整流电路倍周期分岔行为

针对开关电路的周期分岔非线性行为,本文提出一种基于电路拓扑切换序列的分析方法,并运用该方法对基于双向晶闸管的可控整流调压电路在容性负载情况下的倍周期分岔行为进行了分析。文中采用等效电阻的方法建立了双向晶闸管的数学模型;结合其触发导通条件以及整流桥的导通条件,分段建立了系统状态空间描述,进而建立了系统离散迭代映射模型并进行了实验验证;结合系统分岔图及相图,采用拓扑切换序列方法有效分析出系统同时存在边界碰撞分岔及标准倍周期分岔;进一步阐述了造成这两种分岔的原因。研究结果对分析和设计容性负载可控整流电路具有较好的指导意义,对分析类似开关电路的分岔等非线性行为具有一定的参考价值。     

Comparison of Preregulators as Power Savers

Many modern computer, digital communication, and industrial control equipments are furnished dc power by series-pass regulated supplies. At the voltage and current required, these supplies frequently dissipate twice as much power as they pass on to be used. With increasing interest in conserving energy, it has become desirable to minimize the losses of the supplies. This can be done at modest cost by installing a simple preregulator which is itself relatively efficient. This paper presents the experimental results of comparing three methods of preregulation. The three methods chosen can be retrofit in many existing systems. The three are 1) ferroresonant transformer, 2) replacing existing rectifiers with SCR's, and 3) triac throttling of the input. Each of the three methods has some relative advantages, and each has its detractions. On balance, it appears from measurements reported here that triac throttling is the best method.     

高可靠性单相异步电机频繁高速启动触发电路

提出了一种新型低成本过零触发电路，用双向晶闸管代替离心开关，高可靠地控制单相异步电机启动电容的接入和断开，以满足大转矩频繁快速启动的需要。     

双向晶闸管关断暂态研究

对双向晶闸管控制感性负载的关断过程作暂态仿真研究,并给出不同参数条件下关断电压暂态曲线图。     

基于SABER仿真模型的低压复合开关热特性分析

以多路集成复合开关为研究对象,通过建立热模型计算复合开关的临界参数并提高设备的稳定性.SABER仿真模型主要用来分析不同负载条件下复合开关中双向晶闸管温度变化情况,仿真结果可以优化磁保持开关和双向晶闸管的通断控制策略,并且可以为开发大规模集成型复合开关提供帮助.     

A Variable Inductor for Power Applications Using Coupled Circuits

ABSTRACT

In this paper, a variable inductor suitable for power system applications is presented. The inductor variation is based on varying the number of turns in a secondary circuit using triac switches. Unlike thyristor-controlled reactors, the inductance of the proposed reactor is varied in steps but without causing distortion in the inductor current.

Mathematical expression for the effective impedance of the reactor is developed. Theoretical results are compared with those obtained experimentally using a test model.     

Performance prediction of shaded pole induction motors

The authors present an analysis for evaluating the performance characteristics of reluctance-augmented shaded pole motors. The proposed model is based on the d-q axis technique and is valid for steady-state and dynamic conditions. An efficient method of predicting the steady-state operating characteristics of the triac-controlled shaded pole motor is presented. This method calculates the currents and average torque as a function of conduction and control angles of the triac. The effect of critical parameters on the motor performance is investigated. Simulated results are compared with experimental values of a two-pole single phase test induction motor     

A hybrid inverter/cycloconverter-based variable-speed three-phaseinduction motor drive for single-phase inputs

This paper presents a simple converter topology for driving a three-phase induction motor with a single-phase AC supply. Using only two active switches and a triac, the converter can start the motor with high starting torque and low input current, and can bring the motor up to full speed using a very cost-effective, single-phase field-oriented control strategy. The converter supplies balanced output voltages at rated frequency with virtually no output distortion and with very high input power factor. In this paper, the capability contours for different speed ranges and various operating modes are addressed; the trade-offs between output torque, torque ripple, input current distortion, and inverter rating are also explained, and the proposed control approaches are supported by simulation and test results     

A solid-state speed controller for capacitor motors drivingventilation fans

This paper documents the design and testing of an electronic speed controller for permanent-split capacitor motors driving agricultural ventilation fans. The controller was developed and tested with three commercially available and widely used fan systems. Linearized temperature versus airflow rate characteristics were obtained. The controller circuit uses an erasable programmable read-only memory (EPROM) chip. The input to the EPROM is an analog representation of temperature converted to digital form. The digital contents are then converted to an analog signal that triggers a triac and consequently controls the voltage input to the fan motor. A linearized control characteristic can be obtained by storing appropriate voltage values in the EPROM. These values correspond linearly to the desired fan speeds     

Evaluation of modern power semiconductor devices and future trendsof converters

The author reviews the modern power semiconductor devices that appeared in the 1980s, i.e., the insulated gate bipolar transistor (IGBT), static induction transistor (SIT), static induction thyristor (SITH), and the recently introduced MOS-controlled thyristor (MCT). The characteristics of these devices are discussed and compared from the viewpoint of power electronics applications. Although the IBGT is well known, the power electronics community is somewhat unfamiliar with the latter three devices. For completeness, a brief review of other power devices, such as the thyristor, triac, gate turn-off thyristor (GTO), bipolar transistor (BJT), and power MOSFET is also incorporated. Future trends are outlined     

Induction motor drives for domestic appliances

The three-phase induction motor has been adopted for the drive described in this article. The target performance of the drive is based on the requirements for a commercial front-loading washing machine, with a load capacity of 11 lbs., which has an inner drum size of 460 mm. The production washing machine uses a universal motor drive, fed with AC from a phase-controlled triac. The motor rotates the drum through a belt drive, and the pulley ratio is 15:1. The aim is to design the induction motor drive to meet the torque speed needs. The base speed range is 1:14.5 for a wash speed of 55 r/min and a spin speed of 800 r/min. Increased spin speeds are desirable, requiring an extended speed range. Also, a slower “gentle wash” speed may be used. By applying variable frequency, variable voltage with slip control these requirements can be met by a high-speed induction motor operating with a suitable pulley ratio. The experimental drive comprises a high-speed three-phase induction motor fed by an inverter     

Triac Speed Control of Three-Phase Induction Motor with Phase-Locked Loop Regulation

The speed control of a three-phase squirrel cage induction motor by employing triacs in the lines which operate in the normal phase control mode is described. The inherent limitation of low circuit commutated (dv/dt), which makes the triac circuit somewhat unreliable, has been overcome by suitably designing the snubber circuit. The closed-loop speed regulation of the system is then investigated by employing digital phase-locked loop scheme. Compared to the conventional method with antiparallel SCR's and analog servo, the present scheme is somewhat simpler, more economical, and extreme precision in speed control is possible. A complete model of the speed control system has been designed and experimentally evaluated in the laboratory.