Abstract: A new type of PSS-NB power system stabilizer model is proposed. Based on design concept, operating principle and advantage of low frequency oscillation suppression capability, supporting parameter tuning test content and parameter tuning calculation method of PSS model are described in detail. Taking PSS-NB commissioning test of a 330 MW unit as an example, parameter tuning calculation method is presented and low frequency oscillation suppression effect is verified with comparison of traditional PSS2B during engineering application process. It is proved that proposed new PSS-NB can not only meet full-band phase compensation requirements, but also provide better suppression effect on medium and low frequency band.