Continuously variable transmission and system and method of control for high torque events

A transmission control system for controlling a continuously variable transmission (CVT) having a variator assembly, the transmission control system comprising an instruction set, the instruction set executable to:

• command an initial minimum clamping pressure to be applied to the variator assembly to achieve a desired torque capacity;
• determine at least one vehicle operation parameter;
• determine a vehicle condition based on the at least one vehicle operation parameter, the vehicle condition being selectable from at least a first condition (“base condition”), a second condition (“elevated condition”), and a third condition (“high condition”);
• select a compensation strategy based on the vehicle condition, the compensation strategy being selectable from at least a first compensation strategy (“base compensation strategy”), a second compensation strategy (“elevated compensation strategy”), and a third compensation strategy (“high compensation strategy”), the base compensation strategy being selected when the base condition has been determined, the elevated compensation strategy being selected when the elevated condition has been determined, and the high compensation strategy being selected when the high condition has been determined;
• if the elevated compensation strategy has been selected and a predetermined condition has been met, command a second clamping pressure (“elevated clamping pressure”) to be applied to the variator assembly;
• and
• if the high compensation strategy has been selected, command a third clamping pressure (“high clamping pressure”) to be applied to the variator assembly.

A transmission controller for controlling a continuously variable transmission (CVT) having a variator assembly, the transmission controller comprising:

• a first control logic configured to command an initial minimum clamping pressure to be applied to the variator assembly to achieve a desired torque capacity;
• a second control logic configured to determine at least one vehicle operation parameter;
• a third control logic configured to determine a vehicle condition based on the at least one vehicle operation parameter, the vehicle condition being selectable from at least a first condition, a second condition, and a third condition;
• a fourth control logic configured to select a compensation strategy based on the vehicle condition, the compensation strategy being selectable from at least a first compensation strategy, a second compensation strategy, and a third compensation strategy, the first compensation strategy being selected when the first condition has been determined, the elevated second compensation strategy being selected when the second condition has been determined, and the third compensation strategy being selected when the third condition has been determined;
• a fifth control logic configured to command a second clamping pressure to be applied to the variator assembly if the second compensation strategy has been selected and a predetermined condition has been met;
• and
• a sixth control logic configured to command a third clamping pressure to be applied to the variator assembly if the third compensation strategy has been selected.

A continuously variable transmission (CVT) for a motor vehicle, comprising:

• a variator assembly including a first pulley and a second pulley, the first and second pulleys rotatably coupled by a continuous rotatable device, wherein the first pulley is rotatably coupled to an input member and the second pulley is rotatably coupled to an output member;
• the first pulley including a first moveable sheave that is translatable along a first axis relative to a first stationary sheave in response to urging of a first actuator;
• the second pulley including a second moveable sheave that is translatable along a second axis relative to a second stationary sheave in response to urging of a second actuator;
• and
• a control system having at least one controller and one or more sensors in communication with the controller, the control system including an instruction set, the instruction set executable to:
• command an initial minimum clamping pressure to be applied to the variator assembly to achieve a desired torque capacity;
• determine at least one vehicle operation parameter;
• determine a vehicle condition based on the at least one vehicle operation parameter, the vehicle condition being selectable from at least a first condition, a second condition, and a third condition;
• select a compensation strategy based on the vehicle condition, the compensation strategy being selectable from at least a first compensation strategy, a second compensation strategy, and a third compensation strategy, the first compensation strategy being selected when the first condition has been determined, the second compensation strategy being selected when the second condition has been determined, and the third compensation strategy being selected when the third condition has been determined;
• if the second compensation strategy has been selected and a predetermined condition has been met, command a second clamping pressure to be applied to the variator assembly;
• and
• if the third compensation strategy has been selected, command a third clamping pressure to be applied to the variator assembly.