Mechanical-electrical-hydraulic hybrid transmission device and control method thereof

A mechanical-electrical-hydraulic composite transmission device, comprising:

• an input shaft assembly comprising an input shaft and a first clutch;
• a power-split assembly comprising a power-split assembly input shaft, a first gear pair, a second clutch, a power-split assembly ring gear, a power-split assembly planet carrier, and a power-split assembly sun gear, wherein the power-split assembly ring gear is connected to the power-split assembly input shaft, the power-split assembly input shaft is connected to the input shaft through the first clutch, and the power-split assembly ring gear is connected to the power-split assembly planet carrier through the second clutch;
• a hydraulic transmission assembly comprising a third clutch, a variable displacement pump, a hydraulic pipe, a fixed displacement motor, a second gear pair, and a fourth clutch, wherein an input end of the hydraulic transmission assembly is connected to the power-split assembly sun gear, the input end of the hydraulic transmission assembly is connected to the variable displacement pump through the third clutch, the variable displacement pump outputs high-pressure oil to the fixed displacement motor through the hydraulic pipe, and the second gear pair is connected to an output shaft of the fixed displacement motor through the fourth clutch;
• an electrical variable transmission assembly comprising a fifth clutch, a third gear pair, an electrical variable transmission input shaft, an electrical variable transmission, and an electrical variable transmission output shaft, wherein the power-split assembly planet carrier is connected to the electrical variable transmission input shaft through the fifth clutch;
• a mechanical transmission assembly comprising a fourth gear pair, a sixth clutch, a brake, a mechanical transmission assembly input shaft, a fifth gear pair, a seventh clutch, a mechanical transmission assembly ring gear, a mechanical transmission assembly sun gear, an eighth clutch, a mechanical transmission assembly planet carrier, and a mechanical transmission assembly output shaft, wherein the electrical variable transmission output shaft is connected to the mechanical transmission assembly sun gear through the sixth clutch, the brake is connected to the mechanical transmission assembly sun gear, the power-split assembly planet carrier is connected to the mechanical transmission assembly ring gear through the seventh clutch, and the mechanical transmission assembly sun gear is connected to the mechanical transmission assembly planet carrier through the eighth clutch;
• a power-convergence assembly comprising a power-convergence assembly ring gear, a power-convergence assembly sun gear, a power-convergence assembly planet carrier, and a ninth clutch, wherein the power-convergence assembly ring gear is fixedly connected to the mechanical transmission assembly output shaft, the power-convergence assembly ring gear is connected to the power-convergence assembly planet carrier through the ninth clutch, and the power-convergence assembly sun gear is connected to an output end of the hydraulic transmission assembly;
• and
• an output shaft, wherein the output shaft is connected to the power-convergence assembly planet carrier.