TQ-1 satellite is the first technology demonstration satellite of the TianQin project, which is equipped with a high-precision space inertial sensor. In the accelerometer mode, the inertial sensor can measure the non-gravitational forces on the TQ-1 satellite. However, there are many spikes in the inertial sensor measurement. We found that the spikes are mainly caused by the cold gas attitude control thruster, so we try to build physical models to explain these spikes. To begin with, a statistical analysis is used to recover the shape characteristics of the thruster spikes in 3 axes. and then, we introduced an accelerometer response model and an attitude dynamics model that perfectly fits the shape of the thruster spikes. What’s more, by using this model, we can accurately estimate the installation deviation of the thrusters and the center of mass deviation between the inertial sensor and the satellite.