A method of rapidly cooling a high temperature vehicle coolant is disclosed. The method includes determining a coolant temperature lowering entry condition by detecting information on the coolant temperature, an engine speed, and a gear state and determining whether the coolant temperature needs to be rapidly lowered on the basis of the detected information; and changing a number of gear stages by adjusting the number of gear stages of a transmission to be reduced to a specific number of gear stages when the coolant temperature needs to be rapidly lowered in the determining of the coolant temperature lowering entry condition, so that the cooling fan is driven by driving the fan belt through a crank damper pulley using the increased engine speed according to the reducing adjustment of the number of gear stages.

A method of controlling a continuously variable electric drivetrain (CVED) including a high ratio traction drive transmission and at least one of a first motor-generator and a second motor-generator is disclosed. The method includes the steps of receiving a an output speed, determining a kinematic output speed, and determining a slip state of the high ratio traction drive transmission based on a comparison of the output speed to the kinematic output speed.

A method of controlling a continuously variable electric drivetrain (CVED) including a high ratio traction drive transmission and at least one of a first motor-generator and a second motor-generator is disclosed. The method includes the steps of receiving a an output speed, determining a kinematic output speed, and determining a slip state of the high ratio traction drive transmission based on a comparison of the output speed to the kinematic output speed.

A vehicle includes a drive axle, a multi-mode transmission, and a controller coupled to the multi-mode transmission. The multi-mode transmission includes a first gear set having a first planetary gear carrier and a second gear set having a second planetary gear carrier, a first motor/generator coupled to the first gear set, a second motor/generator coupled to the second gear set and selectively coupled to a connecting shaft, a brake positioned to selectively limit a rotational movement of a ring gear of the second gear set when engaged, a first clutch selectively rotationally coupling the first gear set and the second gear set to the drive axle when engaged, and a second clutch selectively rotationally coupling the second motor/generator to the connecting shaft when engaged. The controller is configured to engage the brake and the clutches to selectively reconfigure the multi-mode transmission to an intermediate shift mode of operation.

A vehicle includes a drive axle, a multi-mode transmission, and a controller coupled to the multi-mode transmission. The multi-mode transmission includes a first gear set having a first planetary gear carrier and a second gear set having a second planetary gear carrier, a first motor/generator coupled to the first gear set, a second motor/generator coupled to the second gear set and selectively coupled to a connecting shaft, a brake positioned to selectively limit a rotational movement of a ring gear of the second gear set when engaged, a first clutch selectively rotationally coupling the first gear set and the second gear set to the drive axle when engaged, and a second clutch selectively rotationally coupling the second motor/generator to the connecting shaft when engaged. The controller is configured to engage the brake and the clutches to selectively reconfigure the multi-mode transmission to an intermediate shift mode of operation.

A vehicle includes a connecting shaft, a drive axle, a multi-mode transmission, and a controller. The multi-mode transmission includes a first gear set having a first planetary gear carrier and a second gear set having a second planetary gear carrier, a first motor/generator coupled to the first gear set, a second motor/generator electrically coupled to the first motor/generator and coupled to the second gear set, a brake selectively limiting movement of a portion of the second gear set, and a clutch selectively rotationally coupling the second motor/generator to the connecting shaft. The first gear set is coupled to the connecting shaft, and the planetary gear carriers are rotatably coupled. The controller is configured to selectively configure the multi-mode transmission into an active neutral startup mode of operation by engaging the clutch and the brake such that at least one of the first motor/generator and the second motor/generator produces a voltage.

A vehicle includes a connecting shaft, a drive axle, a multi-mode transmission, and a controller. The multi-mode transmission includes a first gear set having a first planetary gear carrier and a second gear set having a second planetary gear carrier, a first motor/generator coupled to the first gear set, a second motor/generator electrically coupled to the first motor/generator and coupled to the second gear set, a brake selectively limiting movement of a portion of the second gear set, and a clutch selectively rotationally coupling the second motor/generator to the connecting shaft. The first gear set is coupled to the connecting shaft, and the planetary gear carriers are rotatably coupled. The controller is configured to selectively configure the multi-mode transmission into an active neutral startup mode of operation by engaging the clutch and the brake such that at least one of the first motor/generator and the second motor/generator produces a voltage.

A homopolar DC electromagnetic transmission (HET) and an application system thereof are provided. The HET includes two rotors, a stator, an external auxiliary system and an adjustment control system. Each of the rotors has one or more axisymmetric rotor magnetic conductors, and the stator has one or more direct current magnet exciting coils wound around an axis of a rotation shaft. A main magnetic circuit is guided to be a closed ring. The HET includes at least two main magnetic circuits. The HET includes a closed main current loop. The loop is connected with all the rotor magnetic conductors, a rotor electric conductor, a dynamic/static circuit connecting medium, stator conductors and stator magnetic conductors in series or in series and parallel. A direction of main current on the rotor magnetic conductors is perpendicular to a direction of magnetic flux (ϕ) on meridian plane.

A homopolar DC electromagnetic transmission (HET) and an application system thereof are provided. The HET includes two rotors, a stator, an external auxiliary system and an adjustment control system. Each of the rotors has one or more axisymmetric rotor magnetic conductors, and the stator has one or more direct current magnet exciting coils wound around an axis of a rotation shaft. A main magnetic circuit is guided to be a closed ring. The HET includes at least two main magnetic circuits. The HET includes a closed main current loop. The loop is connected with all the rotor magnetic conductors, a rotor electric conductor, a dynamic/static circuit connecting medium, stator conductors and stator magnetic conductors in series or in series and parallel. A direction of main current on the rotor magnetic conductors is perpendicular to a direction of magnetic flux (ϕ) on meridian plane.

When it is determined that there is a likelihood of occurrence of an abnormality in a supercharger, a maximum engine rotation speed and a maximum MG2 rotation speed are changed to a low rotation speed side and operating points of an engine and a rotary machine are controlled such that an engine rotation speed and an MG2 rotation speed are respectively within ranges which do not exceed the changed maximum rotation speeds. Accordingly, even when the supercharger does not operate normally and an abnormal increase in a supercharging pressure occurs, it is possible to curb a high-rotation state of the engine rotation speed and the MG2 rotation speed. As a result, even when an abnormal increase in the supercharging pressure occurs, it is possible to curb a decrease in durability of components.