基于光栅衍射的横向剪切干涉仪精密相移系统设计

基于光栅衍射的横向剪切干涉仪具有很高的检测精度,为满足相移的需要,光栅移相装置需要拥有较大的行程,是干涉仪的关键器件之一。根据干涉仪需求设计了基于柔性铰链及桥式放大机构并利用压电陶瓷驱动的光栅移相装置,利用有限元分析方法对其受力和形变特性进行了分析。利用PI公司的电容传感器及数字压电控制器搭建了测试平台对其进行了测试,获得了开环条件下迟滞特性曲线,在输出电压为100 V时,光栅移相装置的行程可达225μm。实验结果表明,光栅移相装置的行程与理论设计指标接近,满足设计要求。     

高精度压电陶瓷相移器设计

文中采用压电陶瓷柱和自行设计的0-300V直流可调电源制作高精度压电陶瓷相移器,并由计算机通过D/A转换板输出电压进行控制,采用CCD组成闭环反馈.经过标定,相移器的相位误差在±3°之内.该相移器的使用提高光学无损检测的测量精度,而且经济性很好.     

基于CPLD的高精度程控移相器

针对传统的RC移相电路存在误差大、参数固定后移相角度不易调节的问题,提出一种以单片机为主控、CPLD为核心的高精度程控移相器.单片机接收键盘输入的移相指令,计算处理后,通过总线将移相值发送至CPLD,CPLD利用分频、移位寄存、数据选择等实体电路实现移相.仿真波形和实际电路测试均表明,设计的移相器输出波形无失真、移相范围宽、精度高、可步进,步进的最小值可通过改变移位寄存器的时钟频率调节.可应用于锁定放大、正交调制等领域.     

前馈控制算法校正相移微动台非线性运动

压电陶瓷具有推力大,响应速度快,分辨率高和能耗低等优点,但其形变量小,所以需要位移放大机构对其形变量进行放大,实现长行程高分辨率位移。针对压电陶瓷作为驱动器,柔性铰链位移放大装置作为导向机构的相移微动台运动存在非线性问题,采用多项式模型对其位移特性进行建模,通过求解逆多项式获得使其线性运动非线性电压,利用实验对非线性运动校正结果进行验证。实验结果表明,所采用前馈控制算法可以很好的校正相移微动台非线性运动,校正后相移台在x,y方向产生的最大相移误差为4°与3.2°,满足高精度相移干涉测量对相移台相移误差要求。     

剪切干涉仪精密相移系统的研制

设计了一种用于迈克尔逊干涉仪横向剪切相移测量的精密相移系统。该系统采用压电陶瓷驱动器作为驱动元件,通过柔性铰链平移机构推动反射镜实现无摩擦、无间隙微位移。采用电容传感器进行位移反馈测量,利用单片机系统作为中央处理器进行PID闭环控制以实现高精度相移。对相移系统的行程及定位精度进行了测试,当输入阶跃位移信号为80nm时,相移系统输出位移精度小于3nm。当相移系统连续位移2μm,每步位移为80nm时,其输出位移的定位精度小于5nm。实验结果表明,相移系统的行程与定位精度满足剪切干涉仪设计要求。     

大容性负载双极性高压功率放大器设计

设计了一种适合压电陶瓷驱动器等大容性负载动态应用的双极性高压功率放大器,它基于误差放大式原理,采用高压集成运放(PA89)驱动多组并联功率放大级的电路结构,在实现双极性高电压输出的同时具有很强的电流驱动能力.该放大器驱动等效电容为2.5μF的压电陶瓷驱动器时,能实现单端到地-500～+500V高压输出,电压增益40dB...     

基于DSP的电除尘器用高压脉冲电源的设计

采用传统晶闸管相控电源供电的电除尘器存在能耗高、效率低等问题,文章设计了一种可以解决这些问题的电除尘器用高压脉冲电源,该电源主电路主要由移相全桥逆变电路和10组相对独立的脉冲输出单元构成。采用移相全桥ZVT-PWM软开关技术控制逆变电路前后桥臂的相位差;采用同步驱动技术驱动各脉冲输出单元,使各输出脉冲叠加后获得高压脉冲;DSP准确控制电源输出高压脉冲的电压、频率和脉宽。结果表明高压脉冲电源提高了电除尘器的除尘效率,减少了对电网的干扰和电能损耗,能满足多种电除尘的要求。     

一种单片机控制的压电陶瓷微位移器的驱动电路设计

介绍了一种利用AT89C51单片机开关控制压电陶瓷微位移器位移的方法,通过单片机的定时器,在安全的TTL电平下实现对压电陶瓷应变片的高压开关控制。该功能是通过选择合适的耐压场效应管实现的,综合开关速率、耐压性、关断电流等方面的因素,采用的场效应管是IRF610型。作出对压电器件、场效应管的选择以及压电陶瓷应变片的单片机驱动电路的设计,并给出了该系统的控制程序。最后对系统进行了仿真实验,仿真结果表明:驱动电压增大,输出位移量也增大,在驱动电压140～200V时,电压增大和减小2个方向测量得到的位移-电压曲线不是重合的,这表明了压电陶瓷的测量迟滞性,驱动电压在150～190V时,函数的线性度最好,两者的迟滞性误差也最小,据此我们可以选择驱动电压范围为150～190V。     

适用于宽输出范围的混合控制全桥LLC电路

提出了一种针对全桥LLC电路的混合控制方法,在低压低功率情况下采用移相控制,高压高功率情况下采用PFM控制,有效地拓宽了LLC的输出范围。对移相模式下的工况、移相频率的选择及控制方法进行了探讨和研究。搭建了一台2.5 kW、输入100 V、输出150~550 V样机,验证了混合控制方法的可行性和有效性。     

高压低纹波纳米驱动器

针对压电陶瓷进行了纳米级驱动技术的研究,优化了传统的直流放大式驱动技术的系统特性。深度分析了以压电陶瓷为驱动元件的纳米级微位移驱动技术的特性,实现了以下两方面的突破:在设计基于压电陶瓷元件实现纳米精度定位的研究中,设计出了数控压电陶瓷驱动器;深入研究了压电陶瓷容性元件特性后设计出电压恒流源式驱动电路,同时在电路中引入负反馈,稳定了驱动器的输出。通过大量实验证明,该设计很好地解决了压电陶瓷驱动高精度、快响应的难点,具有很高的实用价值。     

一种电流型D类功放高频自激驱动电路

为了解决物理美容设备中电流型D类功放自激驱动栅源电压过高的问题,设计了一种实用电流型D类功放的高频自激驱动电路。通过改变电路中直流偏置电压、MOS管驱动级的电容、漏源间的电容以及两管漏极间电容、供电电压的方法,解决驱动栅源电压过高的问题。通过理论和试验分析,完成电路的设计。通过试验,做到了栅源电压不超过±30V,谐振频率可以达到2MHz左右。该电路具有分离元件少,结构简单,效率高等优点。将该电路实际应用到一款物理美容设备中时,达到了很好的消脂、美白、嫩肤效果。     

用于超声电机的新型驱动电源设计

针对超声电机对激励电源频率、幅值、波形的要求,设计了一种新型超声电机压电陶瓷激励电源.该激励电源输入电压为12 V,经过DC-DC降压变换电路调压后输入4路推挽升压电路叠加输出.输出幅值可达600 V,频率在10～100 kHz范围内可调,同时两路电源间可实现任意相位差.在工作频率范围内无须对压电陶瓷进行阻抗匹配即可基...     

Study and implementation of a 15‐W driver for piezoelectric actuators

This paper studies and implements a 15‐W driver for piezoelectric actuators. The discussed driver is mainly composed of a flyback converter and a power operational amplifier (P‐OPA). The flyback converter produces a variable DC voltage to supply the P‐OPA, which outputs an amplified sinusoidal signal with a DC bias of 100 V to drive the piezoelectric actuator. The power losses can be reduced because the supply voltage of the P‐OPA varies with the peak of the input signal. The power conversion efficiency of the driver can thus be promoted up to more than 30%. From the experimental results, the implemented prototype possesses some advantageous features, such as a nearly constant output‐to‐input voltage gain, a high slew rate, a high input impedance, a low output impedance, and low output voltage ripples. Copyright © 2016 John Wiley & Sons, Ltd.     

Novel Piezoelectric-Based Power Supply for Driving Piezoelectric Actuators Designed for Active Vibration Damping Applications

This paper describes a novel step-up DC-AC piezoelectric-based power supply for driving piezoelectric actuators. Piezoelectric actuators have been demonstrated to be very attractive in applications requiring fast response and high actuation force, such as active damping applications. These actuators are commonly installed in self-powered systems (cars, helicopters, aircrafts, satellites, etc.) with limitation in the battery performance, dimensions and maximum weight. Nevertheless, the required driving electrical AC voltage for these actuators is typically in the range of 100 V to 1000 V, quite far from the 9 to 24 V of common batteries. Thus, the use of heavy, large and EMI-noisy electromagnetic transformers becomes necessary which is a drawback for the compact size required. This paper introduces an alternative system for driving piezoelectric actuators using a novel design of piezoelectric transformer, the Transoner®. The proposed solution allows a reduction in size, weight and magnetic noise generation compared to the classical electromagnetic-based systems. The work represents a completely novel approach to the possibilities of piezoelectric transformers for powering high voltage piezoelectric actuators. The solution offers significant advantages in environments requiring high integration, low weight, and low electromagnetic interferences operated with batteries. A circuit configuration capable of converting a 24 V DC input voltage up to 600 V _pp AC output voltage with frequency and magnitude control is implemented. Experimental results are presented for a standard multilayer piezoelectric actuator driven at 100 V _pp within the range of 10 Hz to 500 Hz.     

一种二线制电流型电阻变送器的电路设计

设计了一种二线制电流型电阻变送器,能把1 000~2 000Ω的电阻量转化为4~20mA的电流量。该变送器由1片运算放大器芯片构成信号调理电路与二线制V/I转换电路,运用零温度系数的恒流源作为被测电阻的激励信号,具有电路简单、线性度高、性能稳定和成本低等特点,且不存在智能仪器可能出现的程序跑飞、死机等异常情况。测试结果表明,精度为0.1级,工作电源电压范围为15~30V。     

High‐voltage power amplifier for flexible paper speaker applications

This letter presents a high‐voltage power amplifier for driving flexible paper speaker. Simple circuit complexity and high signal quality can be achieved. The operating principles and design considerations of the studied paper speaker power amplifier are analyzed and discussed. A laboratory prototype is built and tested. The experimental results are shown to verify the studied scheme. Copyright © 2012 John Wiley & Sons, Ltd.     

一种新型的压电陶瓷驱动电源研究

为了满足压电陶瓷对驱动电源纹波小的要求,基于两路交错并联电源电路的研究,提出了四路交错并联boost 驱动电源电路的拓扑.四路交错并联boost驱动电源电路中的四条支路可减小输入电流纹波,同时还可减小输出电压纹波,可满足压电陶瓷对驱动电源高稳定性、低纹波、高效率的要求.分析了四路交错并联boost电源电路的基本原理,通...     

A waveform generator circuit for extra low‐frequency CMOS micro‐power applications

This paper presents a novel low‐power CMOS extra low‐frequency (ELF) waveform generator based on an operational trans‐conductance amplifier (OTA). The generator has been designed and fabricated using 2.5‐V devices available in 130‐nm IBM CMOS technology with a ±1.2‐V voltage supply. Using the same topology, two sets of device dimensions and circuit components are designed and fabricated for comparing relative performance, silicon area and power dissipation. The first design consumes 691 μW, while the second design consumes 943 μW using the same voltage supply. This low‐power performance enables the circuit to be used in many micro‐power applications. ELF oscillation is achieved for the two designs being around 3.95 Hz and 3.90 Hz, respectively, with negligible waveform distortion. The measured frequencies agree well with the simulation results. The first design is found to provide overall optimal performance compared to the second design at the expense of higher silicon area. Copyright © 2015 John Wiley & Sons, Ltd.     

Design and simulation of novel amplifier‐based mixer for ISM band wireless applications

This letter describes a low‐voltage low‐power (LV‐LP) 2.4‐GHz mixer for Industrial, Scientific and Medical (ISM) band wireless applications. The approach is based on a two‐stage amplifier, and the Gilbert switch stage is inserted between the two amplifier stages. The proposed amplifier‐based mixer delivers a remarkable conversion gain of 13 dB with a local oscillator (LO) power of 7 dBm, while consuming only 1.05‐mW DC power from a 0.8‐V supply voltage. The input‐referred third‐order intercept point (IIP3) of the mixer is 3.82 dBm, and the chip area is only 0.429 mm². The results indicate that this mixer is suitable for the low‐voltage low‐power applications. Copyright © 2014 John Wiley & Sons, Ltd.