多频音调控制器的原理和设计

本文阐述了多频音调控制器的原理、特点和与普通高低音调控制器的区别,介绍了LC、晶体管、集成运放多频补偿器以及频率补偿点的选择、模拟电感原理,最后给出了多频音调控制器的使用方法和测量时的注意事项。     

收录机特种电路和机构的分析及修理多频音调控制器

当前,在中、高级立体声音响设备中出现了一种新型的音调控制器即多频音调控制器,或称多频段图形式音调控制器.它把整个可听音频范围划分为五个、七个或更多的频段,操作者可以根据自己的喜爱以及各种节目的特点独立实现对某一频段的电平提升或衰减,从而对音质进行精细的调整.另外,它具有直观性.我们可以根据面板上的多频音调控制器控制钮的上下位置连起来的图形,作为最后的频响曲     

基于OCP通信事务的SOC调试控制器

基于OCP通信事务进行SOC调试,提高了调试的抽象级别,对于以通信为核心的多核SOC,可以大大提高调试效率.为实现事务级调试,提出基于OCP通信事务的可配置调试控制器.通过分析OCP通信事务,该控制器根据预先配置的触发条件产生本地和远端调试控制信息,从而控制调试过程.通过对实验设计的仿真和综合,验证了调试控制器的功能,并分析了设计的面积开销.     

音调控制器对音响测试结果的影响

1 引言 在测试音响有关参数时,音调控制器的位置对测量数据影响很大。如果音调控制器的位置调不准或错调,会使音响的频率特性和相应特性改变。特别是有些设计不当或生产中质量失控的机器,会影响整机的稳定性。因此,在各种参数测量中,都要明确规定音调控制器位置的原因。     

集成运放多频音调控制电路

多频音调电路是由若干组LC串联谐振回路组合而成的音调控制器,它可以对所需频率进行随心所欲的调节,控制效果明显,是高传真录放声设备上有用的单元电路。由于理想运算放大器可以用虚地来表示,而实际运放的性能又接近理想运放,所以用运算放大器代替分立元件制作多频音调电路时,其性能仅取决于外部反馈网络的特性,而与运放本身性能无关,这种特性使得该音调按制器的设计变得简单。     

图式音调控制集成电路原理及检修

1.应用电路举例现代录音机中愈来愈多地使用图式音调控制器。这种控制器可以用分立元器件构成,而更多的是采用集成电路构成,如图1所示。该电路是图式音调控制集成电路M5226P的应用电路。     

基于Actel FPGA的笔段式LCD驱动设计

笔段式液晶显示器具有低电压,低功耗,体积小,易于开发等特点,广泛应用在各种仪器仪表、电子设备及家用电器等方面。本文介绍的基于FPGA的笔段式LCD驱动器具有灵活性高,扩展性强,可快速构建等特点,与集成电路控制器相比,FPGA更加灵活,     

精密音调控制器

尽管许多追求“原汁原味”的发烧友反对在音响设备中使用音调控制器,担心加入这个“螺蛳”会坏了自己的“一锅汤”,但许多家用音响器材和专业音响设备(如录音棚影剧院使用的调音台)仍在大量使用它。这些不怕“败胃口”的人士认为,将音调控制器当作“味精”在“汤”里适当撒上一些“调调口味”,未必是件坏事。然而要设计一个精确的音调控制器以保证“味道可口”却并非易事。因为立体声左、右通道音调控制电位器的行程和阻值难以达到同步,即使稍有误差也会在两个通道之间产生明显的相位和幅度差异,使声场不能保持准确定位。为了减小电位器的同步误差,可以使用双连线性电位器来担任调控器,但这种电位器的调节特性又与人耳听觉的对数特性不一致。     

自制高保真功率放大器

本文向读者介绍一款适合自制的免调试2×30W功率放大器。它集国内和国外优质集成电路于一体,其造价低而音质优美。电路见图1。该功放的音调部分采用了进口单片直流音调控制集成电路TDA1524A。它具有两路音量、平衡和高、低     

反馈型音调电路的控制特性

本文对反馈型高低音调控制器进行了计算,并对音调网络中某电阻去存所形成的两种电路进行了分析,推导出电路在最大提升与衰减时的幅频特性表达式,其理论数据和曲线显示出不同提升倍数时两种电路的控制特性。文中还确定了反馈型音调电路的最大控制量,最后对该电路进行了小结。文中所给出的幅值计算公式,可使这种音调电路在设计时,描绘出大致的最大控制特性。     

基于FPGA的宽带综合数据光同步网节点控制器设计

节点是控制网络系统的基本构成单元.本文提出了一种基于FPGA的宽带综合数据光同步网节点控制器的设计,简要介绍了宽带综合数据光同步网络及其网络节点,并且给出了网络节点控制器的硬件设计和实现.此设计增强了系统的灵活性,提高了网络节点的可靠性,并且结构简单,适应于不同应用领域的需求.     

Generator speed regulation in the presence of structural modes through adaptive control using residual mode filters

Wind turbines operate in highly turbulent environments resulting in aerodynamic loads that can easily excite turbine structural modes, potentially causing component fatigue and failure. Two key technology drivers for turbine manufacturers are increasing turbine up time and reducing maintenance costs. Since the trend in wind turbine design is towards larger, more flexible turbines with lower frequency structural modes, manufacturers will want to develop control paradigms that properly account for the presence of these modes. Accurate models of the dynamic characteristics of new wind turbines are often not available due to the complexity and expense of the modeling task, making wind turbines ideally suited to adaptive control approaches. In this paper, we develop theory for adaptive control with rejection of disturbances in the presence of modes that inhibit the controller. A residual mode filter is introduced to accommodate these modes and restore important properties to the adaptively controlled plant. This theory is then applied to design an adaptive collective pitch controller for a high-fidelity simulation of a utility-scale, variable-speed wind turbine. The adaptive pitch controller is compared in simulations with a baseline classical proportional integrator (PI) collective pitch controller.     

基于模糊控制的风电机组变桨距控制

针对风力发电机组非线性、时变性的问题,提出采用模糊PID控制器作为变桨距控制器,在风速高于额定风速时,依据风速变化情况调整桨距角,从而使风电机组保持恒功率输出,最后在MATLAB平台上搭建仿真模型。结果表明,采用模糊PID控制比传统PID控制具有更好的动态性能和静态误差,能够优化变桨距控制方法。     

Robust and fault-tolerant linear parameter-varying control of wind turbines

High performance and reliability are required for wind turbines to be competitive within the energy market. To capture their nonlinear behavior, wind turbines are often modeled using parameter-varying models. In this paper we design and compare multiple linear parameter-varying (LPV) controllers, designed using a proposed method that allows the inclusion of both faults and uncertainties in the LPV controller design. We specifically consider a 4.8 MW, variable-speed, variable-pitch wind turbine model with a fault in the pitch system.We propose the design of a nominal controller (NC), handling the parameter variations along the nominal operating trajectory caused by nonlinear aerodynamics. To accommodate the fault in the pitch system, an active fault-tolerant controller (AFTC) and a passive fault-tolerant controller (PFTC) are designed. In addition to the nominal LPV controller, we also propose a robust controller (RC). This controller is able to take into account model uncertainties in the aerodynamic model.The controllers are based on output feedback and are scheduled on an estimated wind speed to manage the parameter-varying nature of the model. Furthermore, the AFTC relies on information from a fault diagnosis system.The optimization problems involved in designing the PFTC and RC are based on solving bilinear matrix inequalities (BMIs) instead of linear matrix inequalities (LMIs) due to unmeasured parameter variations. Consequently, they are more difficult to solve. The paper presents a procedure, where the BMIs are rewritten into two necessary LMI conditions, which are solved using a two-step procedure.Simulation results show the performance of the LPV controllers to be superior to that of a reference controller designed based on classical principles.     

提高宽带毫米波行波管效率研究

针对影响宽带毫米波行波管效率的主要因素,对提高行波管效率的相关实用化技术进行了研究。通过螺旋线线路渐变技术、降低高频损耗、多级降压收集极三个方面的研究,使现有某一宽带毫米波行波管总效率由原来的10%提高到20%以上。     

Innovative adaptive pitch control for small wind turbine fatigue load reduction

As a renewable source of energy, wind is widely used to produce electrical power. The progress of wind turbine technology can greatly benefit from the improvement of control algorithms. The pitch angle control of a horizontal axis wind turbine above the rated wind speed is a challenging issue related to the nonlinear aerodynamic behavior of blades. The linearization of aerodynamic model around nominal operating condition, as well as manufacturing deficiencies, result in unknown parameter uncertainties in a wind turbine model. Therefore, the performance of controller, which is designed based on the mathematical model, defects in practice. In the current paper, an adaptive self-tuning regulator (STR) configuration is proposed for the pitch control, so that the parameters of wind turbine model are constantly estimated and the controller gains are updated based on the assessed parameters. The STR structure consists of a recursive least square estimator and a proportional-integral-derivative (PID) controller with adjustable gains, which are determined by the pole placement method in a real-time routine. The robustness of the closed loop system is investigated by implementation of the control structure on an aero-servo-elastic wind turbine simulator. For the sake of comparison, a baseline gain scheduling PID controller, which is well-accepted for wind turbine pitch control, is designed. A comparison between the simulations of two controllers confirms a significant improvement in the closed-loop performance including less fluctuation of rotor speed and power besides minor fatigue loads on the blades and main-shaft.     

A novel pitch control system for a wind turbine driven by a variable-speed pump-controlled hydraulic servo system

The paper aims to develop a novel pitch control system for a large wind turbine driven by a variable-speed pump-controlled hydraulic servo system. To perform practical pitch control experiments, a full-scale test rig of the hydraulic pitch control system for a 2 MW wind turbine’s blade, including a novel pitch control mechanism, a variable-speed pump-controlled hydraulic servo system, a disturbance system and a PC-based control system, is designed and set up. The variable-speed pump-controlled hydraulic servo system, containing an AC servo motor, a constant displacement hydraulic piston pump two differential hydraulic cylinders and hydraulic circuits, achieved high response and high energy efficiency, so it is suitable for wind turbine applications. Besides, to implement the pitch control in the proposed novel pitch control system, an adaptive fuzzy controller with self-tuning fuzzy sliding-mode compensation (AFC-STFSMC) is developed to design the pitch controller. Finally, the developed variable-speed pump-controlled hydraulic servo system was built and verified for the path tracking control and path-positioning control of the pitch control of the wind turbines by practical experiments in a full-scale test rig under different path profiles, load torques, and random wind speeds.     

一种基于LabVIEW和第三方驱动程序的无线电环境自动测试平台

一种基于LabVIEW和第三方驱动程序的自动化无线电环境测试平台,分别由天线控制转台、总控电脑、频谱仪三部分组成,其中总控电脑分别与天线转动平台、频谱仪相连;而集成于总控电脑中的控制程序包括实时天线转动平台控制和频谱仪控制两个子模块,其中实时天线转动平台控制模块通过串口向天线转台下发当前的方位、俯仰值,频谱仪控制模块通过网线将总控电脑与频谱仪相连具有设置控制频谱仪的观测参数,读取观测数据的功能.     

基于标准系数法的飞机俯仰角控制参数优化

基于标准系数的应用研究结果,对某飞机俯仰角回路进行了标准系数法的设计,给出系统控制器参数.在此基础上,利用Simulink Design Optimization模块,对控制系统参数进一步优化.仿真结果表明标准系数法结合SimulinkDesign Optimization优化对俯仰角系统设计是有效的,而且降低了工作量,提高了工作效率.     

System design for pixel-parallel image processing

A system design for performing low-level image processing tasks in real time is presented. The design is based on large processor-per-pixel arrays implemented using integrated circuit technology. Two integrated circuit architectures are summarized: an associative parallel processor and a parallel processor employing DRAM cells. In both architectures, the layout pitch of one-bit-wide logic is matched to the pitch of memory cells to form high-density processing element arrays. The system design features an efficient control path implementation, providing high processing element array utilization without demanding complex controller hardware. Sequences of array instructions are generated by a host computer before processing begins, then stored in a simple controller. Once processing begins, the host computer initiates stored sequences to perform pixel-parallel operations. A programming framework implemented using the C++ programming language supports application development. A prototype system employs associative parallel processor devices, a controller, and the programming framework. Three sample applications, smoothing and segmentation, median filtering, and optical flow, establish the suitability of the system for real-time image processing