In high-voltage and large-capacity power electronic equipment

using laminated busbar as the main connecting device can reduce the stray inductance of the commutating loops and reduce the voltage spike during the switching transient. Therefore

the design of laminated busbar plays an important role in improving the performance of high-voltage and large-capacity power electronic equipment. Based on the topology of device-parallel active neutral-point-clamped（ANPC）circuit

according to the quantity and the symmetry of the stray inductance of different commutating loops

the effect of different busbar layers and spatial structures on the stray inductance of the commutating loops is compared

and then a four-layer busbar design method with symmetric distribution of power device is proposed. According to double-pulse experiment result for extracting stray inductance

the validity of the stray inductance analysis and accuracy of simulation calculation of each commutating loops of the proposed busbar structure is verified. The design method can be used to effectively reduce the stray inductance of the laminated busbar of device-parallel ANPC circuit and make the stray inductance of each commutating loops symmetrical

which reduces the electrical stress and improves the balance of electrical stress between power devices and improves the reliability of the converter operation effectively.