Internal combustion engine having engine speed limit control system

An engine speed control method, comprising:

• determining a range of allowable engine speeds, such range extending from a low limit, LOW_LIM=cnt_n_lim−K1 to a high limit, LIM_HIGH=cnt_n_lim+K2, where K1 and K2 are predetermined constants, and cnt_n_lim is a function of operator input;
• calculating an error, n_error, between measured engine speed and ctrl_n_lim;
• and
• feeding the error to a feedback controller, such controller producing an engine brake torque, tqe_rpm, command for the engine;
• calculating a torque load, tq_tx, on the engine from a transmission coupled to the engine;
• and
• at least one of initializing such brake torque and such brake torque, tqe_rpm, command as a function of the calculated torque, tq_tx.

A system, comprising:

• an internal combustion engine;
• a transmission coupled to such engine;
• a control unit, such control unit having a feedback controller for providing a producing an engine brake torque, tqe_rpm, command for the engine in response to a torque command, such control unit being programmed to:
• determine a range of allowable engine speeds, such range extending from a low limit, LOW_LIM=cnt_n_lim−K1 to a high limit, LIM_HIGH=cnt_n_lim+K2, where K1 and K2 are predetermined constants, and cnt_n_lim is a function of operator input, for calculating an error, n_error, between measured engine speed and ctrl_n_lim;
• and
• feed the error to the feedback controller, such controller, such controller disabling engine fuel injection when the measured engine speed is greater than LIM_HIGH and enabling fuel injection if the measured speed is within the range.

A system, comprising:

• a control unit programmed to:
• determine a range of allowable engine speeds, such range extending from a low limit, LOW_LIM=cnt_n_lim−K1 to a high limit, LIM_HIGH=cnt_n_lim+K2, where K1 and K2 are predetermined constants, and cnt_n_lim is a function of operator input;
• calculate an error, between measured engine speed and ctrl_n_lim;
• and feed the error to a feedback controller, such controller producing an engine brake torque, tqe_rpm, command for the engine;
• calculate a torque, tq_tx, on the engine from a transmission coupled to the engine;
• and
• at least one of:
• (a) initialize such brake torque;
• (b) and limit such brake torque, tqe_rpm, command as a function of the calculated torque, tq_tx.

A computer executable storage medium having a computer executable program which when executed provides an engine speed control method, such exeecuted program:

• determining a range of allowable engine speeds, such range extending from a low limit, LOW_LIM=cnt_n_lim−K1 to a high limit, LIM_HIGH=cnt_n_lim+K2, where K1 and K2 are predetermined constants, and cnt_n_lim is a function of operator input;
• calculating an error, n_error, between measured engine speed and ctrl_n_lim;
• and
• feeding the error to a feedback controller, such controller producing an engine brake torque, tqe_rpm, command for the engine, such controller disabling engine fuel injection when the measured engine speed is greater than LIM_HIGH and enabling fuel injection if the measured speed is within the range.