The invention relates to a
hybrid power
system with multiple power sources and multiple levels of speed ratios and a control method of the
hybrid power
system. The
hybrid power
system comprises an engine, a bidirectional controllable overrun
clutch, a first motor, a second motor, a multi-speed transmission and a
battery pack. One end of the bidirectional controllable overrun
clutch is connected with an output shaft of the engine. The other end of the bidirectional controllable overrun
clutch is connected with an output shaft of the first motor. A driving part of the multi-speed transmission is connected with the bidirectional controllable overrun clutch. A driven part of the multi-speed transmission is connected with an output shaft of the second motor. The
battery pack supplies power to the first motor and the second motor. By means of switching of the
modes of the bidirectional controllable overrun clutch and switching of gears of the multi-speed transmission, the multiple driving and
energy recovery modes which the multiple power sources can be partially or overall involved in is realized. According to the
hybrid power system, control is simplified, the structure is compact, sliding friction
energy loss caused by the clutch is avoided, the efficiency of a whole vehicle is improved, the
gear ratio of the system lowers the requirement for the performance of the first motor, the fuel economy of the engine is improved, and the energy-saving effect is enhanced.