基于直接信号合成技术电能质量干扰发生器的设计

The design of power quality disturbance generator based on the direct signal synthesis technology

针对高性能的模拟电能质量干扰发生器价格昂贵,难以在普通实验室普及使用的情况,本文基于直接信号合成技术设计了一种模拟电能质量干扰发生器。采用直接频率合成芯片AD9850产生正弦波信号,经椭圆无源低通滤波后进入电能质量波形形成电路;利用单片机控制数模转换芯片DAC7811与电子开关CD4053B,实现暂时过电压、电压短时跌落、电压短时中断以及电压凹陷等功能;利用放大器LM617对信号进行一次放大,通过高压高速集成功率运放PA89A进行二次放大,采用并联三极管扩流技术增大系统输出电流。通过样机试验,该设计能够模拟多种电能质量信号波形,相对经济,能实现大功率。

In this paper, we design a new type of analog power quality disturbance generator baseti on me infect signal synthesis technology to solve the problems such as the disturbance simulator of the existing high performance power quality, is expensive which is not suitable for the use of general laboratory. The sine wave signal is produced by the direct frequency synthesis chip AD9850, and the signal in the power quality waveform shaping after the elliptical pas- sive low-pass filter. The functions of temporary over-voltage, short dips-voltage, voltage short interruption and voltage sag are realized by using Single-chip microcomputer control D/A conversion chip DAC7811 and electronic switch CD4053B. The first is amplified by using amplifier LM617 and the second is amplified by using the power amplifier PA89A which is feautured with high output voltage and high speed, the technology of parallel triode is adopted to in- crease the output current of the system. Through the prototype test, the design can simulate a variety of power quality signal waveforms, relative to the economy and can achieve high power.