说明：  HHT变换matlab程序 在matlab下运行即可，可以修改各种参数，采样点数，各种电能质量原始信号均由程序所得，可以信号叠加而来。比如电压跌落，谐波，暂时上升，中断等。 例子给出的是 电压暂降。
(HHT transform matlab matlab program can be run in, you can modify various parameters, sampling points, a variety of power quality of the original signal by the program proceeds, may signal superimposed from. Such as voltage drop, harmonics, temporary rise interruption. The example given is voltage sags.)