光伏发电是未来新能源发电重要方向之一，而光伏变流器是光伏发电系统的核心。介绍一种基于微网理念的光伏变流器设计。以该变流器为核心的光伏发电系统可以看做一个小型的微网系统。该系统能根据外部电网情况，工作于并网模式和离网模式。介绍了该系统的各个组成部件的设计以及变流器主电路部分器件的选型。最后，由实验样机进行测试。试验结果验证了电路拓扑结构及控制方案的可行性，也说明了系统参数设计方法的正确性。 Abstract: Solar Photovoltaic generation is an impOrtant direction of new energy power generation in the future，while photovoltaic converter is the cOre of photovoltaic generation system. This paper deals with a study on photovoltaic inverter based on the concept of microgrid. This paper describes a system whose cOre component is the photovoltaic inverter，can wOrk on grid-connected mode Or run independently accOrding to the external situation. The paper simply describes the main components of the system. At last，the prototype was produced and tested. Test result has proved feasibility of circuit topology structure and controlling scheme and shown cOrrectness of system parameters.Key wOrds: PV inverter； microgrid； off-grid； stOrage battery
上传时间： 2014-12-24
上传用户：Shaikh
Sensing and/Or controlling current flow is a fundamental requirement in many electronics systems, and the tech-niques to do so are as diverse as the applications them-selves. This Application Note compiles solutions to cur-rent sensing problems and Organizes the solutions by general application type. These circuits have been culled from a variety of Linear Technology documents
标签： 电流检测电路
上传时间： 2013-10-22
上传用户：moshushi0009
When a system designer specifies a nonisolated dc/dc powermodule, considering the needed input voltage range isequally as impOrtant as considering the required perfOrmanceattributes and features. Generally, nonisolated moduleshave either a narrow Or a wide input voltage range. Narrowinputmodules typically have a nominal input voltage of3.3, 5, Or 12 V. FOr systems that operate from a tightlyregulated input bus—such as those that do not use batterybackup—a narrow-input module is often adequate sincethe input remains fairly stable.Offering greater flexibility, wide-input modules operatewithin a range of 7 to 36 V, which includes the popular12- Or 24-V industrial bus. This enables a single module tobe used fOr generating multiple voltages. These modulesare ideal fOr industrial controls, HVAC systems, vehicles,medical instrumentation, and other applications that usea loosely regulated distribution bus. In addition, systemspowered by a rectifier/battery charger with lead-acidbattery backup almost always require wide-input modules.System designers who choose power supplies may wantto take a close look at the latest generation of wide-inputdc/dc modules.
标签： Wide-input modules offer dc
上传时间： 2014-12-24
上传用户：dragonhaixm
Permission to make digital Or hard copies of all Or part of this wOrk fOrpersonal Or classroom use is granted without fee provided that copies arenot made Or distributed fOr profit Or commercial advantage and that copiesbear this notice and the full citation on the first page. To copy otherwise, tOrepublish, to post on servers Or to redistribute to lists, requires priOr specificpermission.
标签： 数字电源
上传时间： 2013-10-16
上传用户：dddddd
Demonstration circuit 1562A is an engineering toolto design and evaluate the LTC699X-X family ofTimerBlox circuits. The center section of the boardcontains a pre-configured TimerBlox function.DC1562A comes in twelve timing function variationsas outlined in Table 1.Surrounding the center board is a ”playground”prototyping area. The prototyping area has padsfOr Dip-8, S8, MS8, Or S6 packages with breadboarding connections to each pin and two convenientpower buses and ground bus surrounding theentire area. This area is fOr conditioning signals tocontrol the timer function and fOr adding loads controlled in time.
上传时间： 2013-10-18
上传用户：如果你也听说
Analog Inputs and Outputs in an S7 PLC are represented in the PLC as a 16-bit integer. Over the nominal span of the analog input Or output, the value of this integer will range between - 27648 and +27648. However, it is easier to use the analog values if they are scaled to the same units and ranges as the process being controlled. This applications tip describes methods fOr scaling analog values to and from engineering units.
上传时间： 2013-11-17
上传用户：3294322651
HIGH SPEED 8051 μC COrE - Pipe-lined Instruction Architecture; Executes 70% of Instructions in 1 Or 2 System Clocks - Up to 25MIPS Throughput with 25MHz System Clock - 22 VectOred Interrupt Sources MEMOrY - 4352 Bytes Internal Data RAM (256 + 4k) - 64k Bytes In-System Programmable FLASH Program MemOry - External Parallel Data MemOry Interface – up to 5Mbytes/sec DIGITAL PERIPHERALS - 64 POrt I/O; All are 5V tolerant - Hardware SMBusTM (I2CTM Compatible), SPITM, and Two UART Serial POrts Available Concurrently - Programmable 16-bit Counter/Timer Array with 5 Capture/Compare Modules - 5 General Purpose 16-bit Counter/Timers - Dedicated Watch-Dog Timer; Bi-directional Reset CLOCK SOURCES - Internal Programmable OscillatOr: 2-to-16MHz - External OscillatOr: Crystal, RC, C, Or Clock - Real-Time Clock Mode using Timer 3 Or PCA SUPPLY VOLTAGE ........................ 2.7V to 3.6V - Typical Operating Current: 10mA @ 25MHz - Multiple Power Saving Sleep and Shutdown Modes 100-Pin TQFP (64-Pin Version Available) Temperature Range: –40°C to +85°C
标签： C8051F020
上传时间： 2013-10-12
上传用户：lalalal
利用单片机具有的智能程序控制的特点，设计了基于STC89C52单片机的"二极管特性测试器"，可对二极管一般特性进行快速测试。通过稳定线性电流源给二极管加载恒定电流，然后由高精度模数转换器测试其压降，以此为基础可判断二极管好坏、检测二极管极性和测试二极管伏安特性等，避免了用万用表测试只能测得极性而不知其特性这一缺点。可用于电子设计制作过程中对二极管进行快速测试，以确定被测二极管是否满足电路的设计要求。 Abstract: By making good use of the intelligent control function of the Micro Controller Unit (MCU)， the diode trait tester was designed based on the STC89C52，which could be used to test the trait of a diode rapidly. By loading constant current to diode through the stable linear current source， and measuring the voltage drop of the diode by high-precision analogue-to-digital converter (ADC)， it can judge whether the diode is good Or not， distinguish the polarity of the diode， and test the trait that the diode， which can avoid the fault of using a multimeter can only measure the polarity but not the trait. This device can be used to test the trait of a diode quickly，and to make sure that whether a diode can be used in the electronic design Or not.
上传时间： 2013-11-13
上传用户：assef
针对科研实验中对拉压千斤顶加载过程控制的需要，采用ATmega128单片机控制步进电机进而实现对执行系统的电动泵站实行自动控制。对力和位移的数据采集与处理及用步进电机控制电动泵站手柄的技术细节作了重点描述。通过单片机的A/D变换器对AMP放大模块采集的电桥信号作量化处理，千斤顶的操控手柄位置依电动油泵阀门开启的方向和大小作若干定位，单片机根据力或位移传感器信号，实时控制步进电机驱动手柄旋转到相应操控位置。 Abstract: This article describes the use of ATmega128 AVR microcontroller series of DBS electric pumping stations and QF100/200 separate twoway hydraulic jack to automate the process of manipulating the wOrk of the technical content. Articles on fOrce and displacement data acquisition and processing， and stepper motOr control electric pump with the handle of the key technical details were described. Through the MCU’s A / D converter module is collected on the AMP amplification quantify the signal bridge， jack handle position control valve opening accOrding to the direction of electric pumps fOr a number of positioning and size of the microcontroller based on fOrce Or displacement sensOr signals， real-time control stepper motOr drive control handle rotate to the appropriate location.
上传时间： 2014-01-16
上传用户：hasan2015
Digitemp JuniOr – An RS-232 POrt-Powered Digital Thermometer Digitemp Jr. is a device that is designed to measure and repOrt ambient temperature. When connected to an RS-232 pOrt on any PC, it will periodically measure and repOrt in ASCII fOrm the ambient temperature in degrees Celsius. These temperature readings can be monitOred with any terminal program. If the terminal program suppOrts capture to disk, the temperature readings can be saved to disk fOr further analysis with a spreadsheet program Or other data analysis tool. The simple ASCII output fOrmat of Digitemp Jr. makes it rel- atively easy to write custom software fOr receiving, recOrding, and analyzing ambient temperature data. Best of all, Digitemp Jr. requires no external power sup- plies Or batteries. It is powered directly by the RS-232 pOrt.
上传时间： 2013-10-21
上传用户：baitouyu
