Based on the conventional lumped parameter circuit model

network equations of piezoelectric transformers (PTs) in parallel-parallel

parallel-series

series-parallel and series-series connection are set up using Y parameter

G parameter

H parameter and Z parameter respectively.All equations are then transformed into Y parameter form

which directly exhibit the relationship between the network characteristics and parameters of single PT and the number of connected PTs.Finally

simulation of electrical characteristics of PTs connected in the four ways is performed

and the theoretical analysis is verified by experiments of parallel-parallel connection.It shows that

only the parallel-parallel connection and parallel-series connection can increase voltage gain and output power.