The invention discloses a piezoelectric energy 
collection system and a control method thereof. The piezoelectric energy 
collection system comprises a piezoelectric energy collector, an active 
rectifier, a Buck-
boost converter, an asynchronous 
control circuit, a self-startup precharge circuit, a 
peak detection circuit, an 
inductance input-end 
voltage zero-crossing detection circuit, a VDD-end 
energy storage unit, a 
charge current zero-crossing detection circuit of the VDD-end 
energy storage unit, a VST-end 
energy storage unit, a 
charge current zero-crossing detection circuit of the VST-end energy storage unit, an inter-storage-unit energy conversion circuit, an LDO 
voltage-stabilizing circuit, a VDD internal 
voltage-stabilizing circuit and a low-power 
reference current source and reference voltage generation circuit. According to the invention, an ultralow-power 
design technology is introduced, a conventional circuit structure is improved, performance optimization and structural innovation are performed on each circuit module, static 
power consumption of the whole circuit 
system is reduced to 111.1nW, and the 
energy conversion efficiency is as high as 89.4%. Besides, the 
system also has the advantages of small 
chip area, high integration, complete 
automation, high 
adaptive capacity to environment and the like.