The commutation strategy for brushless DC motor (BLDCM) based on flux-linkage function is extremely sensitive to current noise. Especially, the values of function fluctuate greatly at low speeds, resulting in commutation lead or even mis-commutation. In order to suppress the fluctuation, a flux-linkage function with an integrator is implemented after a deep analysis of fluctuation mechanism. In addition, for eliminating the effect of zero drift and integral initial error, a structure is designed by replacing the integrator with a band pass filter. Meanwhile, an accurate commutation point can be obtained by adjusting the center frequency of the filter dynamically. Furthermore, a novel method for identification of commutation point is proposed. The effect of the fluctuation is reduced, and the accuracy and reliability of the commutation point are improved. Simulation results show that the proposed strategy based on the new flux-linkage function can obtain accurate and reliable commutation signal under the comprehensive constraints of low speed and current noise, which can ensure the stable operation of BLDCM.