Marine propulsion system with efficient engine speed delta

• US 9,156,536 B1
• Filed: 05/22/2014
• Issued: 10/13/2015
• Est. Priority Date: 08/17/2012
• Status: Active Grant

• Current Assignee: Brunswick Corporation
• Original Assignee: Brunswick Corporation
• Inventors: Arbuckle, Jason S., Snyder, Matthew W., Kirchhoff, Thomas S.
• Primary Examiner(s): Cheung, Mary
• Assistant Examiner(s): Trivedi, Atul
• Application Number:
  US14/284,795
• Time in Patent Office: 509 Days
• Field of Search: 701/21, 701/42, 701/85, 114/102.1, 114/102.13, 114/275
• US Class Current: 1/1
• CPC Class Codes: B63B 79/20 using models or simulation, e.g. statistical models or stochastic models
• CPC Class Codes: B63B 79/30 for diagnosing, testing or predicting the integrity or performance of vessels
• CPC Class Codes: B63C 11/42 with independent propulsion or direction control
• CPC Class Codes: B63H 2021/216 using electric control means
• CPC Class Codes: B63H 21/20 the vessels being powered by combinations of different types of propulsion units
• CPC Class Codes: B63H 21/21 Control means for engine or transmission, specially adapted for use on marine vessels
• CPC Class Codes: F02B 61/045 for marine engines
• CPC Class Codes: F02D 11/02 characterised by hand, foot, or like operator controlled initiation means
• CPC Class Codes: F02D 11/105 characterised by the function converting demand to actuation, e.g. a map indicating relations between an accelerator pedal position and throttle valve opening or target engine torque
• CPC Class Codes: F02D 11/106 Detection of demand or actuation
• CPC Class Codes: F02D 2011/102 at least one throttle being moved only by an electric actuator
• CPC Class Codes: F02D 2041/1409 using at least a proportional, integral or derivative controller
• CPC Class Codes: F02D 2041/141 using a feed-forward control element
• CPC Class Codes: F02D 2200/602 Pedal position
• CPC Class Codes: F02D 31/002 controlling air supply
• CPC Class Codes: F02D 9/02 concerning induction conduits throttle valves, or arrangements thereof in conduits F02D9/08
• CPC Class Codes: Y02T 70/00 Maritime or waterways transport

Abstract

A system and method is provided for efficiently changing controlled engine speed of a marine internal combustion engine in a marine propulsion system for propelling a marine vessel. The system responds to the operator changing the operator-selected engine speed, from a first-selected engine speed to a second-selected engine speed, by predicting throttle position needed to provide the second-selected engine speed, and providing a feed forward signal moving the throttle to the predicted throttle position, without waiting for a slower responding PID controller and/or overshoot thereof, and concomitant instability or oscillation, and then uses the engine speed control system including any PID controller to maintain engine speed at the second-selected engine speed.

Claims

1. A method for changing controlled engine speed of a marine internal combustion engine in a marine propulsion system for propelling a marine vessel, wherein said engine is operated at an operator-selected engine speed and an engine speed control system maintains engine speed at said operator-selected engine speed, said engine having a throttle controlling engine speed according to throttle position,

said method comprising:

responding to an operator changing said operator-selected engine speed, from a first-selected engine speed to a second-selected engine speed, by predicting throttle position needed to provide said second-selected engine speed;

providing a feed forward signal moving said throttle to said predicted throttle position;

moving said throttle, in response to said operator changing said operator-selected engine speed from said first-selected engine speed to said second-selected engine speed, to attempt to set engine speed at said second-selected engine speed; and

after moving said throttle to said predicted throttle position, using said engine speed control system to maintain engine speed at said second-selected engine speed.

2. The method according to claim 1 further comprising:

moving said throttle to said predicted throttle position in response to said feed forward signal, without waiting for said engine speed control system to move said throttle.

3. The method according to claim 2 wherein said engine speed control system is subject to overshoot when attempting to set engine speed at said second-selected engine speed in response to said operator changing said operator-selected engine speed from said first-selected engine speed to said second-selected engine speed, and comprising:

moving said throttle to said predicted throttle position in response to said feed forward signal without said overshoot otherwise caused by said engine speed control system.

4. The method according to claim 2 wherein said engine speed control system includes at least one PID controller, and comprising:

reducing an amplification gain of said PID controller otherwise needed to accommodate said change from said first-selected engine speed to said second-selected engine speed, and instead accommodating said change by said predicted throttle position provided by said feed forward signal, whereby said PID controller amplification gain need only be large enough to maintain said engine speed at said second-selected engine speed, without having to accommodate said change from said first-selected engine speed to said second-selected engine speed, said reduced amplification gain providing enhanced stability of said PID controller.

5. The method according to claim 1 comprising:

responding to said operator changing said operator-selected engine speed, from said first-selected engine speed to said second-selected engine speed, by predicting throttle position needed to provide requisite engine airflow per cylinder, APC, needed to provide said second-selected engine speed;

using a normalized APC calculation to predict required throttle position to achieve said second-selected engine speed.

6. The method according to claim 5 comprising using a normalized APC calculation as follows:

7. The method according to claim 5 comprising:

predicting an engine load at said second-selected engine speed;

converting said predicted engine load to a predicted APC;

calculating a corrected APC by compensating said predicted APC for a given parameter; and

calculating a normalized APC from said corrected APC.

8. The method according to claim 1 further comprising:

moving said throttle to said predicted throttle position in response to said feed forward signal, without waiting for said engine speed control system to move said throttle;

wherein said engine speed control system includes at least one PID controller, and comprising;

reducing an amplification gain of said PID controller otherwise needed to accommodate said change from said first-selected engine speed to said second-selected engine speed, and instead accommodating said change by said predicted throttle position provided by said feed forward signal, whereby said PID controller amplification gain need only be large enough to maintain said engine speed at said second-selected engine speed, without having to accommodate said change from said first-selected engine speed to said second-selected engine speed, said reduced amplification gain providing enhanced stability of said PID controller;

responding to said operator changing said operator-selected engine speed, from said first-selected engine speed to said second-selected engine speed, by predicting throttle position needed to provide requisite engine airflow per cylinder, APC, needed to provide said second-selected engine speed;

using a normalized APC calculation to predict required throttle position to achieve said second-selected engine speed;

predicting an engine load at said second-selected engine speed;

converting said predicted engine load to a predicted APC;

calculating a corrected APC by compensating said predicted APC for barometric pressure; and

calculating a normalized APC from said corrected APC.

9. A marine propulsion system with efficient changing of controlled engine speed of a marine internal combustion engine in a marine propulsion system for propelling a marine vessel, wherein said engine is operated at an operator-selected engine speed and an engine speed control system maintains engine speed at said operator-selected engine speed, said engine having a throttle controlling engine speed according to throttle position,

said marine propulsion system with efficient changing of controlled engine speed comprising a control circuit having a processor, a memory, and an input/output interface, wherein the control circuit:

responds to said an operator changing said operator-selected engine speed, from a first-selected engine speed to a second-selected engine speed, by predicting throttle position needed to provide said second-selected engine speed;

provides a feed forward signal moving said throttle to said predicted throttle position;

moves said throttle, in response to said operator changing said operator-selected engine speed from said first-selected engine speed to said second-selected engine speed, to attempt to set engine speed at said second-selected engine speed; and

after said movement of said throttle to said predicted throttle position, uses said engine speed control system to maintain engine speed at said second-selected engine speed.

10. The marine propulsion system according to claim 9 wherein said control circuit moves said throttle to said predicted throttle position in response to said feed forward signal, without waiting for said engine speed control system to more said throttle.

11. The marine propulsion system according to claim 10 wherein said engine speed control system is subject to overshoot when attempting to set engine speed at said second-selected engine speed in response to said operator changing said operator-selected engine speed from said first-selected engine speed to said second-selected engine speed, wherein said control circuit moves said throttle to said predicted throttle position in response to said feed forward signal without said overshoot otherwise caused by said engine speed control system.

12. The marine propulsion system according to claim 10 wherein said engine speed control system includes at least one PID controller, wherein said control circuit reduces an amplification gain of said PID controller otherwise needed to accommodate said change from said first-selected engine speed to said second-selected engine speed, and instead accommodates said change by said predicted throttle position provided by said feed forward signal, whereby said PID controller amplification gain need only be large enough to maintain said engine speed at said second-selected engine speed, without having to accommodate said change from said first-selected engine speed to said second-selected engine speed, said reduced amplification gain providing enhanced stability of said PID controller.

13. The marine propulsion system according to claim 9 wherein said control circuit:

responds to said operator changing said operator-selected engine speed, from said first-selected engine speed to said second-selected engine speed, by predicting throttle position needed to provide requisite engine airflow per cylinder, APC, needed to provide said second-selected engine speed;

uses a normalized APC calculation to predict required throttle position to achieve said second-selected engine speed.

14. The marine propulsion system according to claim 13 wherein said control circuit uses a normalized APC calculation as follows:

15. The marine propulsion system according to claim 13 wherein said control circuit:

predicts an engine load at said second-selected engine speed;

converts said predicted engine load to a predicted APC;

calculates a corrected APC by compensating said predicted APC for a given parameter; and

calculates a normalized APC from said corrected APC.

16. The marine propulsion system according to claim 9 wherein said engine speed control system includes at least one PID controller, and wherein said control circuit:

moves said throttle to said predicted throttle position in response to said feed forward signal, without waiting for said engine speed control system to move said throttle;

reduces an amplification gain of said PID controller otherwise needed to accommodate said change from said first-selected engine speed to said second-selected engine speed, and instead accommodates said change by said predicted throttle position provided by said feed forward signal, whereby said PID controller amplification gain need only be large enough to maintain said engine speed at said second-selected engine speed, without having to accommodate said change from said first-selected engine speed to said second-selected engine speed, said reduced amplification gain providing enhanced stability of said PID controller;

responds to said operator changing said operator-selected engine speed, from said first-selected engine speed to said second-selected engine speed, by predicting throttle position needed to provide requisite engine airflow per cylinder, APC, needed to provide said second-selected engine speed;

uses a normalized APC calculation to predict required throttle position to achieve said second-selected engine speed;

predicts an engine load at said second-selected engine speed;

converts said predicted engine load to a predicted APC;

calculates a corrected APC by compensating said predicted APC for barometric pressure; and

calculates a normalized APC from said corrected APC.

17. A non-transitory computer-readable medium having computer-executable instructions for performing a method for changing controlled engine speed of a marine internal combustion engine in a marine propulsion system for propelling a marine vessel, wherein said engine is operated at an operator-selected engine speed and an engine speed control system maintains engine speed at said operator-selected engine speed, said engine having a throttle controlling engine speed according to throttle position,

said method comprising:

responding to an operator changing said operator-selected engine speed, from a first-selected engine speed to a second-selected engine speed, by predicting throttle position needed to provide said second-selected engine speed;

providing a feed forward signal moving said throttle to said predicted throttle position;

moving said throttle, in response to said operator changing said operator-selected engine speed from said first-selected engine speed to said second-selected engine speed, to attempt to set engine speed at said second-selected engine speed; and

after moving said throttle to said predicted throttle position, using said engine speed control system to maintain engine speed at said second-selected engine speed.

18. The non-transitory computer-readable medium having computer-executable instructions according to claim 17 wherein said method comprises:

moving said throttle to said predicted throttle position in response to said feed forward signal, without waiting for said engine speed control system to move said throttle;

wherein said engine speed control system includes at least one PID controller, and comprising;

reducing an amplification gain of said PID controller otherwise needed to accommodate said change from said first-selected engine speed to said second-selected engine speed, and instead accommodating said change by said predicted throttle position provided by said feed forward signal, whereby said PID controller amplification gain need only be large enough to maintain said engine speed at said second-selected engine speed, without having to accommodate said change from said first-selected engine speed to said second-selected engine speed, said reduced amplification gain providing enhanced stability of said PID controller;

responding to said operator changing said operator-selected engine speed, from said first-selected engine speed to said second-selected engine speed, by predicting throttle position needed to provide requisite engine airflow per cylinder, APC, needed to provide said second-selected engine speed;

using a normalized APC calculation to predict required throttle position to achieve said second-selected engine speed;

predicting an engine load at said second-selected engine speed;

converting said predicted engine load to a predicted APC;

calculating a corrected APC by compensating said predicted APC for barometric pressure; and

calculating a normalized APC from said corrected APC.