原标题：Microchip dsPIC DSC离线1KVA UPS参考设计

　　UPS(不间断电源)电源是在主电源不能供电时能够提供持续稳定不间断的电源供应的重要外部设备.UPS按工作原理分成离线式、在线式与在线互动式三大类.UPS有着广泛的用途,从小功率个人电脑到中功率如医疗设备,生活支持设备,数据存储和能量设备到大功率如通信设备,工业生产和在线管理系统等.本文首先介绍了UPS的基本情况和基本驱动电路.接着介绍采用microchip的SMPS dsPIC® 数字信号控制器(DSC)的1KVA的参考设计,包括主要指标,方框图和详细电路图.

　　Offline UPS Reference Design Using the dsPIC® DSC

　　An Uninterruptible Power Supply, or UPS, is an electronic device that provides an alternative electric power supply to connected electronic equipment when the primary power source is not available.

　　Unlike auxiliary power, a UPS can provide instant power to connected equipment, which can protect sensitive electronic devices by allowing them to shut down properly and preventing extensive physical damage. However, a UPS can only supply energy for a limited amount of time, typically 15 to 20 minutes. Although its use can extend to a virtually unlimited list of applications, in past years the UPS has become even more popular as a means of protecting computers and telecommunication equipment, thus preventing serious hardware damage and data loss.

　　UPS systems provide for a large number of applications in a variety of industries. Their common applications range from small power rating for personal computer systems to medium power rating for medical facilities, life-support systems, data storage, and emergency equipment, and high power rating for telecommunications, industrial processing, and online management systems. Different considerations should be taken into account for these applications. As an example, a UPS for emergency systems and lighting may support the system for 90-120 minutes. For other applications like computer backup power, a UPS may typically support the system for 15-20 minutes. If power is not restored during that time, the system will be gracefully shut down.

　　Types of UPS Systems

　　A typical UPS for computers has four basic protection roles: being able to cope with power surges, voltage shortage, complete power failure and wide variations in the electric current frequency. There are three types of UPS systems, depending on how the electric power is being stored and relayed to the electronic device connected to them:

　　• Offline UPS (also known as Standby UPS)

　　• Line-Interactive (or Continuous UPS)

　　• Online UPS (often called double conversion supply)

　　OFFLINE UPS

　　An Offline UPS system redirects the electric energy received from the AC input to the load and only switches to providing power from the battery when a problem is detected in the utility power. Performing this action usually takes a few milliseconds, during which time the power inverter starts supplying electric energy from the battery to the load.

　　图1.离线UPS方框图

　　图2.在线互动式UPS方框图

　　图3.在线UPS方框图

　　The reference design describes the design of an Offline Uninterruptible Power Supply(UPS) using a Switch Mode Power Supply (SMPS) dsPIC® Digital Signal Controller (DSC).

　　The Offline UPS Reference Design consists of three major UPS topology blocks:

　　• Push-Pull Converter (steps up the DC battery voltage to a constant high-voltage DC)

　　• Full-Bridge Inverter (converts DC voltage to a sinusoidal AC output)

　　• Flyback Switch Mode Charger (current source and charges battery with constant current)

　　离线UPS I/O 指标

　　图4.离线UPS参考设计框图

　　图5.基本驱动电路图

　　图6.整流电路图

　　图7.离线UPS参考设计电路图(1)

　　图8.离线UPS参考设计电路图(2)

　　图9.离线UPS参考设计电路图(3)

　　图10.离线UPS参考设计电路图(4)

　　图11.离线UPS参考设计电路图(5)

　　图12.离线UPS参考设计电路图(6)

　　图13.离线UPS参考设计电路图(7)

　　图14.离线UPS参考设计电路图(8)