A single-shunt resistance current reconstruction method for sensorless control of permanent magnet synchronous motor is proposed, which solves the problem that single-shunt structure cannot be applied to over modulation applications. This method divides the area where the current cannot be sampled by a single-shunt structure into two types. According to different types, the appropriate output phase of the inverter is selected, by inserting an effective pulse into the selected phase; the phase current can be measured. This method can achieve the same current reconstruction results as the three-shunt structure under the condition that the output of three-phase PWM is symmetrical. Experiments and simulation results show that this method can not only improve the voltage utilization rate, but also significantly reduce switching losses.