Some new models and algorithms are used, they are: zero impedance branch, orthogonal transformations, and measurement error estimation etc.

The EMTDC simulations indicate that the method can find out the faulty line correctly and prove that the analysis of the angle-frequency characteristic of zero impedance of the line is correct.

When measuring the charge on a device such as a capacitor, it's important to disable the zero check of the electrometer first, and then connect the capacitor to the high impedance input terminal.