无人机DC／DC电源的小型化设计

介绍了无人机机载DC／DC电源的发展要求,分析该种电源小型化设计的难点所在．同时对进一步实现电源小型化的途径作了分析和探讨,最后给出了电源小型化的实例。     

基于模糊控制的无人机应急电源快速充电方法

无人机应急电源作用重大但标配设备充电耗时且不够安全.通过分析电源的充电特性,根据模糊控制理论提出了一种通过查表运算实施快速模糊控制的非线性充电方法,并以MC68HC05SR3单片机为控制核心,设计出针对某型无人机应急电源的智能控制充电系统,优化了充电曲线,提高了充电速度.实验结果表明,该系统具有良好的快速响应曲线,可实现充电电流的最优控制,安全高效.     

无人机的主要电磁干扰源及抑制方案

本文简单分析无人机系统的电磁干扰问题,指出其主要干扰源为二次电源、发动机电火花、机身电缆等.并详细给出二次电源电磁干扰的抑制方案,并简单介绍了发动机电火花和电缆的抗电磁干扰方案.     

机载计算机电源的小型化设计

介绍了机载计算机电源的现状,同时对进一步实现电源小型化的途径作了分析和探讨,最后给出了电源小型化的实例。     

高可靠性无人机地面变频电源设计

本文就SPWM技术在无人机地面变频电源中的应用情况作了介绍,就有关设计和使用中的工程技术问题进行了初步探讨,提出了电源噪声抑制,提高电磁兼容性和抗干扰性以及可靠性的工程实现方法,解决了一机多出和发电机转速模拟问题。首次成功地将SPWM技术应用到小型无人机地面变频电源中,大大提高了变频电源的可靠性,为无人机变频电源开拓了广阔的前景。     

系留无人机中继通信系统研究

由无人机携带的通信中继装备(如基站、无线电台等)在提高网络容量、扩大网络覆盖范围方面具有巨大的潜力,但是却存在着因自带电源有限而飞行时间短、难以建立无人机与地面站间可靠通信链路等缺点,而系留无人机中继通信系统则可有效解决这些问题。文章描述系留无人机中继通信系统的构成,分析系留无人机中继通信系统的优势,指出系留无人机中继通信系统的缺点,介绍系留无人机中继通信系统的应用场景。     

复合材料无人机航电系统的改进设计

以复合材料无人机的航电系统为研究对象,根据无人机整体设计要求,设计满足需求的航电系统.该系统以自动驾驶仪为控制核心,采用内部集成的A/D转换器采集工作电压,实时监测无人机的电源电压;内部集成的姿态测量系统和INS/GPS组合导航系统,采集无人机的姿态与位置数据;通过串口与无线数据电台相连,实现无人机与地面控制站之间的通信;通过I/O口连接超声波测距仪,实时测量无人机与地面的相对高度;其输出的RS485控制信号与各个舵机等执行部件相连,实现对无人机执行部件的控制.该复合材料无人机的航电系统功能齐备,采用模块化设计,接口方便.在此硬件平台上开发控制算法,可满足本复合材料无人机系统的工作要求.此外,给出了航电各子系统间的布局、电缆敷设的优化方法,并对航电系统联合调试需要注意的问题进行了讨论.     

电动无人机的动力系统构成

目前市面上见到的无人机动力系统主要是活塞发动机系统及电力动力系统两类,而电力动力系统由于其能量密度大、体积小、重量轻、易于维护等特点,占到了民用无人机的绝大多数,本文就对电动无人机的动力系统构成方面进行了比较详细的介绍。     

国内外无人机系统的研究现状

随着信息时代的到来,无人机系统作为一种重要的信息技术手段,凭借着其较高的鲁棒性和自主能力,成为了今后各领域发展与应用的首选,包括军事建设领域和民用领域.无人机与有人机最大的不同在于自主控制技术,这也是无人机实现无人操控、执行各种任务的关键.本文关于无人机系统的研究,在这里简单从无人机救援、抗灾的视角,表述无人机系统的应用和研究现状.     

无人机光电侦察、监视技术研究

无人机是获取战场情报、进行监视和侦察活动的最佳平台,已成为未来战争中的重要武器,而其情报、监视和侦察能力的提升更依赖于无人机光电系统技术的发展.从无人机的侦察、监视任务出发,详细介绍了无人机上的各种光电侦察,监视设备,并分析了各种光电设备的优缺点和应用现状;系统研究了无人机光电系统的侦察、监视技术,并对无人机光电系统的搜索、跟踪等关键技术进行了详细研究;最后对无人机光电系统的发展趋势加以预测和展望.     

一种数字化交、直流双向变流器的设计

文中提出一个新颖实用的交、直流变换器拓扑结构,论述数字式交、直流双向变流器的工作原理,功率变换电路控制策略以及功率变换回路如何选择主要器件及其参数,并通过小批量产品来验证变换器运行的正确性。     

采用电流矢量控制的电流型PWMAC/DC变换器非线性控制策略的研究

文章提出了一种采用电流矢量PWM控制的非线性控制策略，该方案通过电流矢量PWM控制来跟踪电流指令，从而简化了电流型PWM AC／DC变换器波形发生。在建立电流型PWM AC／DC变换器d-q模型基础上，采用输入输出线性化方法实现了解耦控制，给出了理论分析和调节器参数整定算法，并利用Mallab对控制策略进行了仿真，获得了预期效果。     

A low-cost CMOS dual-mode AC/DC data converter for signal measuring technique

A low-cost CMOS dual-mode AC/DC data converter for signal measuring technique is newly proposed. Instead of traditional full wave rectification, the realized synchronous rectification circuit is more attractive due to the easier integration and lower cost. In this paper, the design strategies of implementing the signal processing of AC and DC modes in the integrated circuit are discussed completely. Proven through SIMULINK in system level and SPICE simulations in circuit level, simulation results show that the proposed dual-mode AC/DC data converter achieves 8-bit resolution in DC mode and 7-bit resolution in AC mode. Measurement results have successfully verified the correct functions and performance of the proposed data converter and confirmed it for AC/DC signal measuring technique. The area of this chip is 710 × 630 μm² and the measured power consumption is 5.1 mW. The proposed dual-mode AC/DC data converter is suitable for the system of analog and mixed-signal boundary scan.     

An Improved Single Stage Phase Shifted Control Based AC–DC PFC Converter for Wireless Applications

Recently, many researchers has more attention in a single stage AC to DC converter features and DC to DC regulator are extensively used into low power applications. When compared with the two stage conventional method over the Single stage converter has a simple design and utilize only less components. Therefore, this task has been used in this paper as a prposed work of AC–DC single stage converters combine a converter front end with DC–DC back end converter. This proposed work has been improved single stage power factor correction (PFC) converter based on phase-shifted controller for wireless Power applications. The proposed technique employed to develop the improved converter for task of an extensive series of voltage outputs with rippleless outcomes in low frequency, that shows the high essential in battery application and the PFC duty ratio restriction is eradicated. Similarly, DC–DC stage operation are designed in a related way of conventional full bridge phase shifted converter. Accordingly, the proposed technique of improved converter of this paper will achieves better efficiency compared with other conventional techniques and it has been prove more efficient for many Industrial applications, it has been discussed in result section clearly. The experimental results of proposed improved converter proves that it is potential to extend high power single stage converter with good power factor, conversion characteristics and efficiency.

     

一种低功耗原边反馈AC/DC转换器

低待机功耗、高效率的绿色电源已成为未来电源技术发展的方向,国际上已经正式提出六级能效标准。提出了一种采用常规工艺实现的原边反馈AC/DC转换器电路,解决了传统原边反馈AC/DC转换器元器件多、待机功耗大以及用高压特殊工艺实现低待机功耗的成本昂贵等问题。该原边反馈AC/DC转换器能够满足六级能效标准。     

大功率电弧加热器电源的设计研究

研究了63MW等级的大功率电弧加热器交直流电源的主电路设计和控制策略。提出了一种相移叠桥组合晶闸管整流主电路结构,使得该电源输出直流电压从1kV到21kV的不同工况时,其输入端的功率因数不小于0.9,且高功率时THD小于5%。根据主电路相移叠桥结构的特点,提出了一种非线性反馈控制器和前馈控制器相结合的复合稳流控制策略,稳流精度能够达到0.1%。实验结果表明,相移叠桥组合晶闸管主电路结构达到了电源电能质量设计指标;采用复合稳流控制策略后,稳流精度不仅能够达到设计指标,而且可以去掉主电路中的稳流电阻,从而减小了电源系统1.8MW的电阻热耗。     

Voltage-source charge-pump power-factor-correction AC/DC converters

Voltage-source charge-pump power-factor-correction (VS-CPPFC) AC/DC power converters are proposed in this paper. The PFC converter using the CP concept is first derived. The unity power factor condition is derived and analyzed. The clamping technique is used to satisfy the unity power factor condition. Based on the steady-state analysis, design considerations for the CPPFC stage are discussed. A family of VS-CPPFC topologies is also presented. The proposed VS-CPPFC AC/DC power converter was implemented and tested. The experimental results show that 83.5% efficiency and 0.996 power factor can be achieved for a half-bridge CPPFC AC/DC converter with 250-W and 12-V output,     

逆变器综合课程设计教学平台的开发

“电力电子技术”是一门理论性与实践性均较强的课程,软开关逆变电源实验装置是为该课程设计的综合课程设计教学平台。该平台由交错并联有源箝位正激直流变换器和软开关桥式逆变器构成,分别采用脉宽调制控制策略和离散脉冲控制策略。本文详细分析了逆变电源的工作原理,给出了实验结果和教学平台应用过程,讨论了电感的设计过程和电源稳压原理。通过该教学平台,可加深学生对“电力电子技术”课程内容的理解,锻炼学生的动手能力,有效提高了教学质量。     

A new modulation strategy for a buck-boost input AC/DC converter

This paper presents a novel modulation strategy for a power factor corrected (PFC), isolated AC/DC converter derived from the integration of a nonisolated, two switch buck-boost AC/DC converter with an isolated dual active bridge DC/DC converter (2SBBDAB). This strategy, termed discontinuous leading/trailing edge (DLTE) modulation, serves to maximize the duty cycle of the input switch while keeping the current in the buck-boost inductor discontinuous. Hence, the crest factors of the currents in the switching devices are minimized, the input switch is turned on at zero current and the zero-voltage switching ranges of the bridge switches are unaffected by the integration. A conventional isolated, PFC AC/DC converter typically consists of a boost converter cascaded with a forward converter. The ratings required of the power switching devices of the 2SBBDAB employing the DLTE modulation strategy are similar to those required of the conventional design for wide line voltage operation. However, the 2SBBDAB converter has higher line voltage surge immunity than that of the conventional design and, unlike the conventional design, it has inherent inrush current limiting. The DLTE modulation strategy may be applied to the family of converters composed of the two switch buck-boost integrated with half and full-bridge forward converters