Muzzle Voltage of Conventional and Augmented Railguns

Muzzle voltage is often used to describe the contact state of armature–rail interface, which can be divided into induced voltage, contact resistance, and armature resistance. In this article, the calculation method of mutual inductance coefficient and induced voltage is proposed based on the simplified 2-D model, and the calculation is carried out based on the current waveform in the experiment. A comparison between theoretical calculations and experimental results shows that the muzzle voltage of the conventional railgun is much greater than the induced voltage. It is generally believed that the armature resistance is negligible, so the contact resistance is the main component of the muzzle voltage. Then, it is feasible to judge the contact state of the armature–rail interface by the change of the muzzle voltage. In contrast, the muzzle voltage of the augmented railgun is mainly from the induced voltage, and it is not easy to determine whether a transition has occurred. We need other methods to determine whether the augmented railgun is fired successfully or not.