资源描述
外文资料Belt conveyor driveReduced voltage starting with increase of transmitting a driving power, during the acceleration control winding rotor induction motor around the rotor induction motor directly connected to the driving system; direct current (DC) motor transport most drive using a DC shunt motor; 1.2 hydraulic coupler; hydrodynamic coupling device is often referred to as hydraulic coupler, consists of three basic single; between the shaft and the driven shaft dont need any mechanical connection; a fixed charge hydraulic coupler fixed charge hydraulic coupler is in the structure is simple; the variable filled hydraulic coupler is also known for the moment type hydraulic coupler; spoon control of hydraulic couplingThe buck starts with the increase of the transmission drive power in the During acceleration control motor torque becomes more and more important. Because the motor torque is a function of the voltage, the voltage applied to the motor must be under control, general with silicon controlled rectifier (SCR a buck start-up device, sincere and low voltage tension conveyor belt, and linear increase in supply voltage until the full voltage and maximum speed. However this starting in a way that does not produce stable acceleration, when the acceleration is completed, the motor voltage of the SCR control lock in the guide, the motor provides full pressure. Such control power can reach 750kW.Wound rotor induction motor winding rotor induction motor directly connected to the drive system Reducer through in the rotor windings of the motor in series resistance torque control of motor. In at the start of a transmission device, the resistor in series in the rotor to generate a low torque, when the conveyor belt speed, the resistance is gradually reduced steadily increasing torque. In multi drive system, an additional slip resistance may will always be connected in series in the circuit of rotor winding to help load sharing. The motor system design is relatively simple, but the control system may very complex, because they are based on the computer control of the resistive switching. Nowadays, the majority control system is custom designed to meet the specifications of transmission system around the rotor motor is suitable for 400 KVV above the system.Drive direct current (DC) motor transport most use DC shunt motor, the motor armature in the external connection. Controlled DC drive technique is generally used for SCR device, which allows continuous variable speed operation of DC drive system in machinery is simple, but design of electronic circuits, monitoring and control the whole system, compared to other soft start system is expensive, but in torque, load sharing and transmission for the main consideration occasions, it is a reliable, saving the cost of the DC motor general use in larger power conveying device, including should play the conveying belt tension control of multi drive Dynamic systems and transmission devices that require a wide range of transmission.Hydrodynamic coupling is often referred to as the hydraulic coupler, consists of three basic units: as the impeller of the centrifugal pump, promote hydraulic turbine and put into the shell of the two power components. Fluid from the impeller to the turbine, on the driven shaft torque. Torque and speed because of the circulating fluid in drivingShaft and the driven shaft does not need any mechanical connection. This connection power generated by the decision to hydraulic coupling of the filling quantity, the torque is proportional to the input speed. Because in the fluid coupling output speed less than the input rate, the difference therebetween said to slip, generally 1% - 3%. Transmission power of up to several thousand kilowatts.A fixed charge hydraulic coupler fixed charge hydraulic coupler is in relatively simple in structure and has only limited the bending part of the conveying device most commonly used soft start device, the structure is relatively simple and low cost, can provide excellent soft start effect on now use most of the conveyor.Variable filled hydraulic coupler, also known as torque hydraulic coupler limited. Coupling of the impeller installed in the AC motor, turbine is installed on the driven gear for high-speed shaft on, containing the operating components of the axle box is installed on the driving base. Coupling the rotating shell with an overflow outlet allow the liquid to continuously from the working chamber midstream Into a separate auxiliary chamber, oil from the auxiliary chamber through a heat exchanger pump to control electromagnetic valve of coupler filling liquid quantity. In order to control the starting torque of the single motor driving system must be monitoring of AC motor current to the solenoid valve control provide feedback. Variable filled hydraulic coupler can be used in power delivery system and the power can reach thousands of kilowatts the drive is very complex both in mechanical, or electrical driving system at moderate cost.Spoon pipe control hydraulic coupler is also known for the variable speed fluid couplings. This hydraulic coupler is also by three standard coupling unit form, i.e., an impeller, a turbine and a A housing containing loop. This hydraulic coupler need outside the working chamber setting catheter (also known as spoon pipe) and luminal and rely on adjusting device to change the spoon pipe opening (scoop tube and the top end of the rotation of the shell of spacing) artificially change the working cavity of the filling quantity, so as to realize the output speed regulation. This control provides a reasonably smooth acceleration, but the computer control system is very complex. Spoon pipe control hydraulic coupler can be used in single or multiple machine drive system, power range for 150kW-750kW.Variable frequency controlVariable frequency control is also a direct drive mode, it has a very unique high performance.VFC Device for induction motor with changes in the frequency and voltage, excellent starting torque and acceleration.VFC equipment is a power electronic controller, first of all, the AC is rectified into DC, then using the inverter, then transforms the DC frequency, driving voltage controllable AC. VFC adopts vector control or direct torque control (DTC) technology, can according to different load with different speed.VFC driving energy according to the given s curves start or stop, to achieve automatic tracking started or stopped curve.VFC drive for conveying belt started to provide excellent control of speed and torque, also can for the multi machine drive system For load sharing.VFC controller can be easily installed on the conveyor drive power is small. Past when in high voltage, VFC device structure due to the power semiconductor devices rated voltage value restrictions become very complex, high voltage transmission often use low-voltage inverter, and then use the step-up transformer at the output, or using a plurality of low voltage inverter in series to solve. And simple device series connection of two level inverter system compared due to the series between devices easily pressure and output can be a better harmonic characteristics, three level voltage type PWI inverter system in several megawatts industrial transmission in recent years won 750kW/ system has been successfully installed in the belt conveyor drive system of the long 2 71m two in the coal mine of three 2.3kv VFC.Neutral point three level inverter using IGBTDue to tandem device voltage sharing easy, low device each time the switch of DV / dt and output good harmonic performance, the three-level voltage inverter in high power drive applications become more and more popular. Voltage IGBT (HV-IGBT) makes application of three-level neutral point box have a principle of high-voltage inverter design Greater scope of application. This inverter can now be achieved from 2. RV to 4. 16Kv full scope of application.HV-IGBT module series can be used in 3. RV and 4. 16Kv equipments2. AV each inverter switch only needs a HV-IGBT2,3.Main power inverter circuitHigh voltage AC drive applications. Compared with a two-level voltage type inverter, three-level midpoint box voltage type inverter provides three voltage levels to the output terminal, for the same quality of output current, the switching frequency can be reduced to the original 1 / 4, the switching devices of rated voltage S2u s4u and S3u and S2u S1u trunk additional value can be reduced to the original 1 / 2, attached to the motor transient voltage stress may also be reduced to the original 1 / 2. Three level neutral point voltage type inverter switch state can be summarized in Table 1, u, V and W respectively represents three, P, N and G is a DC bus three points. For example, when the switch is closed, u are in a state of P (positive bus bar voltage), on the contrary, when the switch is closed, u are in a state of n (negative bus voltage). In the neutral case, the phase in the o state, then on the basis of the phase current polarity is positive or negative, or conduction or s In order to ensure that the neutral point voltage is balanced, the average current injected at the o point should be zero at 3U.As commonly used 12 pulse diode rectifier to the DC link capacitor charging, introduced at the input end of the harmonic is very small. If the input harmonic have higher requirements, using a 24 pulse diode rectifier as input converter. The need to have the ability to regenerate more advanced, you can use an active input converter instead of diode rectifier and then input rectifier and inverter output for the same structure.Inverter controlMotor controlled induction motor control can be used in rotor field oriented vector control Is implemented through the use of PWM modulator completed the constant torque and high speed in the field weakening region. Figure 2 shows the indirect vector control block diagram of figure in the flux command a psi R is function of velocity, velocity feedback and feedforward slip control signal Sichuan HMU. The addition results of frequency signal integration, although after generation unit vector (COS theta E and sinO theta E) and finally through the vector rotator generate voltage V angle theta control PWM modulator.Inverter. Its basic principle is that the three level PWM modulator uses two reference waves to recognize Ur1 and Ur2, but only use a triangular wave. It is determined in an optimized way every time Switch time.Switching frequency harmonics generated by as much as possible is small, the use is as low as possible to minimize the switching losses; the zero sequence components are added to each reference Tripoli to the relative position of the maximization of fundamental voltage. An additional degree of freedom as the reference wave and triangle wave can be changed, it can be for the current balance of DC link midpoint.Three level inverter 3V of three 750kW/ after Zhuang coal mine 2. 7 km. Long belt conveyor drive system successfully installed, on the performance of the variable frequency drive system (VFC) were tested. The test results show that the control system using VFC belt The excellent characteristics of conveyor. Figure 3 for test results and waveforms. Shown by the figures, curve 1 shows controlled belt speed, belt speed with the S-shaped curve shape curve 2,3, respectively, which indicated that current and torque, curve 4 shows tension belt. From the figure can be found with the tension fluctuation range is small, all test results show a belt conveyor drive system satisfactory characteristics.In recent years, conveyor drive control technology have been more reliable, consistent with the cost-effective and efficient driving drive system provides users with a choice. In these choices, variable frequency control (VFC) showing in the future long distance conveying belt conveyor Plays an important role. Using the midpoint of the high-pressure work GBT block three level inverter itself can provide high voltage power supply to the motor terminals, so that the inverter control application more simple. By Zhuang coal mine 2. 7 km long belt conveyor in the midpoint of the clamped three-level inverter VVVF (VFC) control system test results show that, using the midpoint of the BV-IGBT block three level inverter and rotor flux vector control strategy of induction motor variable frequency drive is used, the belt conveyor drive system has very good performance, showing a good application prospect.中文译文皮带输送机的驱动降压启动随着传送驱动功率的增加，在加速期间控制使绕线转子感应电机绕线转子感应电机直接连接到驱动系；直流(DC)电机大多数传送驱动使用DC并励电机，；1.2液力偶合器；流体动力偶合器通常被称为液力偶合器，由三个基本单；轴和从动轴之间不需要任何机械连接；固定充液液力偶合器固定充液液力偶合器是在结构较简；可变充液液力偶合器也称为限矩型液力偶合器；勺管控制液力偶合降压启动 随着传送驱动功率的增加，在加速期间控制使用的电机扭矩变得越来越重要。由于电机扭矩是电压的函数，电机电压必须得到控制，一般用可控硅整流器(SCR构成的降压启动装置，先施加低电压拉紧输送带，然后线性的增加供电电压直到全电压和最大带速。但是，这种启动方式不会产生稳定的加速度，当加速完成时，控制电机电压的SCR锁定在全导通，为电机提供全压。此种控制方式功率可达到750kW。绕线转子感应电机 绕线转子感应电机直接连接到驱动系统减速机上，通过在电机转子绕组中串联电阻控制电机转矩。在传送装置启动时，把电阻串联进转子产生较低的转矩，当传送带加速时，电阻逐渐减少保持稳定增加转矩。在多驱动系统中，一个外加的滑差电阻可能将总是串联在转子绕组回路中以帮助均分负载。该方式的电机系统设计相对简单，但控制系统可能很复杂，因为它们是基于计算机控制的电阻切换。当今，控制系统的大多数是定制设计来满足传送系统的特殊规格绕线转子电机适合于需要400kVV以上的系统。直流(DC)电机 大多数传送驱动使用DC并励电机，电机的电枢在外部连接。控制DC驱动技术一般应用SCR装置，它允许连续的变速操作。DC驱动系统在机械上是简单的，但设计的电子电路，监测和控制整个系统，相比于其他软启动系统的选择是昂贵的，但在转矩、负载均分和变速为主要考虑的场合，它又是一个可靠的，节约成本的方式。DC电机一般使用在功率较大的输送装置上，包括需耍输送带张力控制的多驱动系统和需要宽变速范围的输送装置上。流体动力偶合器通常被称为液力偶合器，由三个基本单元组成:充当离心泵的叶轮，推进水压的涡轮和装进两个动力部件的外壳。流体从叶轮到涡轮，在从动轴产生扭矩。由于循环流体产生扭矩和速度，在驱动轴和从动轴之间不需要任何机械连接。这种连接产生的动力决定于液力偶合器的充液量，扭矩正比于输入速度。因在流体偶合中输出速度小于输入速度，其间的差值称为滑差，一般为1%-3%。传递功率可达几千千瓦。固定充液液力偶合器 固定充液液力偶合器是在结构较简单和仅具有有限的弯曲部分的输送装置中最常用的软启动装置，其结构相对比较简单，成本又低，对现在使用的大多数输送机能提供优良的软启动效果。可变充液液力偶合器 也称为限矩型液力偶合器。偶合器的叶轮装在AC电机上，涡轮装在从动减速器高速轴上，包含操作部件的轴箱安装在驱动基座。偶合器的旋转外壳有溢出口，允许液体不断地从工作腔中流出进入一个分离的辅助腔，油从辅助腔通过一个热交换器泵到控制偶合器充液量的电磁阀。为了控制单机传动系统的启动转矩，必须监测AC电机电流给电磁阀的控制提供反馈。可变充液液力偶合器可使用在中大功率输送系统中，功率可达到数千千瓦口这种驱动无论在机械，或在电气上都是很复杂的，其驱动系统成本中等。勺管控制液力偶合器 也称为调速型液力偶合器。此种液力偶合器同样由三个标准的液力偶合单元构成，即叶轮、涡轮和一个包含工作环路的外壳。此种液力偶合器需要在工作腔以外设置导管(也称勺管)和导管腔，依靠调节装置改变勺管开度(勺管顶端与旋转外壳间距)人为的改变工作腔的充液量，从而实现对输出转速的调节。这种控制提供了合理的平滑加速度，但其计算机控制系统很复杂。勺管控制液力偶合器可以应用在单机或多机驱动系统，功率范围为150kW-750kW。变频控制变频控制也是一种直接驱动方式，它具有非常独特的高性能。VFC装置为感应电机提供变化的频率和电压，产生优良的启动转矩和加速度。VFC设备是一个电力电子控制器，首先把AC整流成DC，然后利用逆变器，再将DC转换成频率、电压可控的AC. VFC驱动采用矢量控制或直接转矩控制(DTC)技术，能根据不同的负载采用不同的运行速度。VFC驱动能根据给定的S曲线启动或停车，实现自动跟踪启动或停车曲线。VFC驱动为传送带启动提供了优良的速度和转矩控制，也能为多机驱动系统提供负载均分。VFC控制器可以容易地装在小功率输送机驱动上。过去在中高电压使用时，VFC设备的结构由于受电力半导体器件的电压额定值限制而变得很复杂，中高电压的变速传动常常使用低压逆变器，然后在输出端使用升压变压器，或使用多个低压逆变器串联来解决。与简单的器件串联连接的两电平逆变器系统比较，由于串联器件之间容易均压以及输出端可以有更好的谐波特性，三电平电压型PWI逆变器系统在数兆瓦工业传动中近年来获得了越来越多的应用。由三台750kW/ 2.3kv的这种逆变器构成的VFC系统已经成功安装在成庄煤矿长2. 71m二的带式输送机驱动系统中。使用IGBT的中性点箱位三电平逆变器由于串联器件电压均分容易，器件每次开关的dv/dt低以及输出端出色的谐波品质，三电平电压型逆变器在大功率传动应用中变得越来越流行。高压IGBT(HV-IGBT)的出现使得应用三电平中性点箱位原理的中高压逆变器设计有了更大的应用范围。这种逆变器目前可以实现从2. RV到4. 16kV全范围的应用。HV-IGBT模块串联可使用在3. RV和4. 16kV的设备。2. AV逆变器每个开关只需要一个HV-IGBT2,3。主功率逆变电路高压交流传动应用的需要。与两电平电压型逆变器相比，三电平中点箱位电压型逆变器提供三个电压级别给输出端，对于同样的输出电流品质，开关频率可降低到原来的1/4,开关器件的电压额定值可减小到原来的1/2，附加到电机上的额外的瞬态电压应力也可能减少到原来的1/2。 三电平中点箱位电压型逆变器的开关状态可归纳于表1，U，V和W分别表示三相，P, N和G是直流母线上的三个点。例如，当开关S1u和S2u闭合时，U相处于状态P(正母线电压)，反之，当开关S3u和S4U闭合时，U相处于状态n(负母线电压)。在中性点箱位时，该相在o状态，这时根据相电流极性的正负，或者是S2U导通或者是S3U导通。为了保证中性点电压平衡，在o点被注入的平均电流应该是零。为通常使用12脉冲二极管整流器给直流环节电容器充电，在输入端引入的谐波是很小的。若对输入谐波有更高的要求，可以使用24脉冲二极管整流器作为输入变流器。对于需要有再生能力的更高级应用，可以用一个有源输入变流器取代二极管整流器，这时输入整流器与输出逆变器为同一结构。逆变器控制电机控制感应电机的控制可以使用转子磁场定向矢量控制器实现，通过使用PWM调制器完成了恒转矩区和高速弱磁区的控制。图2为间接矢量控制框图图中指令磁通甲r是速度的函数，反馈速度和前馈滑差控制信号川赫目加。对相加结果的频率信号积分，然后产生单位矢量(cos e和sinOe )，最后通过矢量旋转器产生电压V角控制PWM调制器。逆变器。其基本原理是三电平PWM调制器使用两个参考波认Ur1和Ur2，但只使用一个三角波。它以一种优化方式确定每一次开关时刻。产生的谐波尽可能的小，使用尽可能低的开关频率以最小化开关损耗;可将零序成分加到每一个参考波里以便最大化基波电压。作为一个附加的自由度，参考波与三角波的相对位置可改变，这可以用于直流环节中点的电流平衡。三个750kW/ 2. 3V三电平逆变器在成庄煤矿2. 7km.长带式输送机驱动系统成功安装之后，对整个变频传动系统(VFC)的性能进行了测试，测试结果显示出使用VFC控制系统的带式输送机的优良特性。图3为测试结果波形。由图看出，曲线1显示受控带速，带速呈S形曲线形状，曲线2、3分别表示电流和扭矩，曲线4显示带张力。从图中可以发现，带张力的波动范围很小，所有检测结果显示出带式输送机驱动系统令人满意的特性。近年来输送机驱动控制技术的进步已更为可靠，符合低成本效益和高效驱动的驱动系统为用户提供了选择。在这些选择中，可变频率控制(VFC)的方法显现出在将来长距离输送中带式输送机扮演了重要的角色。使用高压工GBT的中点嵌位三电平逆变器本身可以提供电机终端所需的供电中高压，使变频控制的应用更为简单。通过成庄煤矿2. 7km长带式输送机中采用的中点嵌位三电平逆变器变频调速(VFC)控制系统的测试结果表明，采用BV-IGBT的中点嵌位三电平逆变器以及使用转子磁场矢量控制策略的感应电机变频传动，使带式输送机驱动系统具有非常优秀的性能，显示出良好的应用前景。
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