In order to overcome the oneness of the traditional detection method in the non-sinusoidal and unbalanced system，this paper presents a new kind of calculation matrix based on the symmetric component method.It can easily calculate the positive/negative/zero-sequence and generalized reactive current，it can also calculate the asymmetric harmonic and asymmetric active/reactive current，and the three-phase power factors，etc at one go.Using the principle of amplitude-phase to build the calculation matrix that can easily calculate many parameters based on unbalanced fundamental current，which is the calculation principle.This method can be used for the three-phase three-wire（or four-wire）system，single-phase system，as it can for the automation of electric power systems，and it may be also convenient for the detection system of a variety of power quality control devices.And we can easily set the function of those devices when considering their compensation capacity and whether they can compensate for the unbalance of the active power.Finally，the theoretical analysis and experimental results both show the validity and feasibility of the method.