参数故障诊断和容差问题是模拟电路故障诊断的两个主要难题。该文从故障建模入手,提出一种新的复数域参数故障统一建模方法。模拟电路输出电压的实部和虚部都是故障元件参数的函数,联立实部和虚部函数,并消掉被建模元件参数,得到与参数无关的函数。该函数只由电路结构、故障元件位置和无故障元件的参数确定。因此,以它作为故障模型就与参数无关,能描述任何参数漂移、开路和短路故障。该模型函数是二次函数,除了无故障点之外,不同元件的模型函数会在复平面上相交于第二个点,称为混叠问题。该文采用多频方法来消除此混叠现象。仿真结果验证了方法的有效性。 Parametric fault diagnosis and tolerance problems are two major problems in analog circuit fault diagnosis. Starting with fault modeling, this paper proposes a new method of unified fault parameter modeling in complex domain. The real part and the imaginary part of the output voltage of the analog circuit are both the functions of the faulty component parameters, the simultaneous real part and the imaginary part function, and the components of the modeled component are eliminated to obtain the function that is independent of the parameter. This function is only determined by the circuit structure, the location of the faulty component and the parameters of the fault-free component. Therefore, using it as a fault model is independent of the parameters and can describe any parameter drift, open circuit, and short circuit fault. The model function is a quadratic function. Except for non-point-of-failure, the model functions of different components intersect at the second point on the complex plane, which is called the aliasing problem. This paper uses multi-frequency method to eliminate this aliasing phenomenon. Simulation results verify the effectiveness of the method.