电源选型推荐

整个DTU系统的电源解决方案，主要考虑到不间断供电的问题，所以需要双电源供电的一个供电形式，主流的供电方式一般是有两部分组成，一部分是大功率300W或者500W的AC/DC充电电源，这个电源一般两路输出，一路给后级的板卡进行供电，一方面给后级的蓄电池或者是超级电容进行充电；另外的一部分就是蓄电池或者超级电容，这个主要是在市电断电的情况下，保证整个系统的正常运行。另外，电网对于EMC方面的要求比较苛刻，特别是浪涌方面，需要完全满足4级的要求。主电源和蓄电池都掉电时，系统掉电保持时间500mS以上。

根据上面的应用描述，我们推荐选用金升阳MBP500-2A54D54的接线式电源，它具备电池充电功能，可对48V 铅酸电池充电；工业级工作温度：-40℃～+70℃；2500VAC 高隔离电压；大瞬时过功率达540W；优越的EMC性能；接线式安装。

另外，如果铅酸电池的电压值为24V，还可以选用金升阳公司的MBP300-2A27D27的接线式电源，可对24V的铅酸电池充电，稳态功率达到351W。
电源是各种电子设备必不可缺的组成部分,其性能优劣直接关系到电子设备的技术指标及能否安全可靠地工作。目前常用的直流稳压电源按功率管的工作方式分为线性电源和开关电源两大类。线性稳压电源亦称串联调整式稳压电源,电路技术比较成熟。具有低纹波、高稳压性能等优点。但由于必须使用工频变压器,且调整管工作在线性放大区,因而体积大和重量大、效率低。开关电源调整管工作在高频开关状态,功率损耗小,且使用小体积的高频变压器替代笨重的工频变压器来实现电压变换和电网隔离。
为解决传统的PWM型变换器的上述问题,可采用谐振、准谐振、多谐振以及具软开关的PWM型变换器。这些变换器吸收、利用了PWM型变换器中的寄生参数或外加电感、电容作为谐振参数,使变换器中的功率开关在零电压或零电流下开通和关断,开关两端的电压或经过开关的电流是正弦或半正弦波形。因此大大减少开关的瞬问损耗和开关应力以及电磁干扰和射频干扰.使其工作频率可进一步提高到1Mhz以上，效率达90%以上。再加上小型片状电子元器件,包括磁性材科,例如:平板型变压器等以及表面安装技术以及散热方式的改进，就使电源系列、标准化、模块化成为现实。

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