4EMH COMPANY, PRS200. 3 AC Operation Manual, 2000. 2.
5LUOZK, XUZJ, ZHENGYC, etal. DFTand DSP2 based electric energy measurement algorithm of harmonic source load [J]. Power System Technology, 2002, 4 (10): 2487- 2490.
3Hou Zong-hao. Design and implementation of heartbeat inmuhi-machine environment [ C ]. //Advaced Information Networking and Applications, 2003:583-586.