The electromechanical coupling dynamics of half coated metal core piezoelectric fiber array is analyzed by calculating the effective voltage in half cycle. The expression of harvest voltage and power is derived in two cases of uniformed fibers and different fibers. When the geometry parameters of the fibers meet normal distribute, the normalized harvesting power affected by the variance of radius ratio, length of fiber and angle of half electrode is simulated. The results show that the normalized harvesting power is lower with bigger difference of the fiber geometry parameters. To improve the normalized harvesting power with different direction of environment vibration every fiber needs an ACDC transfer circuit.