The invention provides a throttling system capable of improving efficiency of a power grid. The throttling system comprises a first circuit, a second circuit and a third circuit, the second circuit and the third circuit are connected in parallel in the power grid, the third circuit is connected with a main circuit in series, and a throttling module is connected in series in the second circuit; thefirst circuit is connected with a singlechip and a first mutual inductor in series, the first mutual inductor is used for supplying power, a second mutual inductor in charge of monitoring current inreal time is also connected in the second circuit, the second mutual inductor is connected with the throttling module in series, the second mutual inductor is connected with the singlechip, and the singlechip is connected with an intelligent switch; and the third circuit is connected with a main switch in series. The system provided by the invention monitors and controls current in a power transmission line in real time by utilizing the throttling module arranged on the power transmission line and cooperating with the second mutual inductor and performs intelligent selection on functions of the throttling module by utilizing the singlechip to receive a signal transmitted by the second mutual inductor, so that timely automatic throttling power supplying performed when a power supply line isin an overload state and even short circuit is realized, power consumption is prevented, and power utilization security of a user is also improved.