To address the issues that

after distinguishing critical loads(CL)and non-critical loads(NCL)in conventional electric spring(ES)

the NCL cannot operate under rated voltage

and that the AC-AES electric spring suffers from complex commutation and a limited compensation range

a bipolar Buck-Boost AC-AC electric spring(BBAC-ES)was proposed based on the operating principle of bipolar voltage regulation in AC-AC converters. The operating mechanism and voltage compensation strategy of the BBAC-ES were systematically analyzed. The input-output voltage relationship and compensation principle of the proposed topology were derived through theoretical analysis. Furthermore

a comparative study between the BBAC-ES and ex

isting ES topologies was conducted. The results show that the proposed BBAC-ES eliminates the need to distinguish between CL and NCL

and achieves natural commutation of switches without introducing dead time or increasing control complexity. In addition

by coordinating two duty cycles

d

1

and

d

2

the BBAC-ES is capable of realizing both in-phase and out-of-phase buck-boost operations

effectively mitigating voltage fluctuations of +110% and -40%

thereby maintaining stable voltage across critical loads. The compensation range of the proposed topology is approximately three times that of the conventional AC-AES. Finally

simulation studies and a 1 kW experimental prototype are carried out to validate the effectiveness of the proposed BBAC-ES in stabilizing load voltage under fluctuating grid conditions.