高精度数控可调直流稳压电源设计

针对常规直流稳压电源的输出电压精度不高和调节较为繁琐的缺点,设计了一款高精度数控可调直流稳压线性电源。该电源输出电压0～30V可调,输出电流最大值可达4A。通过输出电压/电流取样电路、差动放大电路及电压/电流调整电路等所构成的闭环负反馈环节和软件上的双线性插值误差补偿方法,提高了输出电压的精度。该电源输出电压和电流的最大值既可通过旋转编码器和实体按键进行调节,也可以通过在所用触控液晶模块中创建的虚拟键盘直接进行设置,操作简便。实际测试结果表明,该电源的输出电压精度高,12V输出时的负载调整率仅为0.15%,且参数设置操作简便,可满足一般教学、科研的应用需求。

Design of a digitally-controlled high-precision DC power supply with adjustable output voltage

With a view to the shortcomings of conventional DC power supply＇s output voltage in low precision and cumbersome regulation, a digitally-controlled high-precision linear DC power supply with adjustable output voltage is presented. The voltage regulation range of the proposed power supply is from 0 V to 30 V, and the maximum output current is 4 A. The precision of the out- put voltage has been improved by adopting the closed-loop feedback segment which comprises a voltage and current sampling cir- cuit, a differential amplifier and parameters adjusting circuit in hardware, and the bilinear interpolation error-amended algorithm in software. The values of output voltage and maximum output current can be regulated by a conventional rotary encoder and some buttons, and also can be set up directly by means of the established virtual keyboard on LCD touch screen. The test results indi- cate that the output voltage＇s precision of the designed power supply is high and the load regulation is only 0.15% at 12V output voltage. Moreover, the manipulation of the setting parameters is simple and convenient meeting the application demands for ordinary teaching and research.