Engine control device, engine control system, and engine control program

Patent metadata

Field	Value
Publication number	US-12378928-B2
Application number	US-202318728400-A
Country	US
Kind code	B2
Filing date	Jan 20, 2023
Priority date	Jan 26, 2022
Publication date	Aug 5, 2025
Grant date	Aug 5, 2025

Abstract

An engine control device includes: an injection command unit for outputting a fuel injection amount command value; a first calculation unit for outputting a fuel injection amount obtained by FB calculation based on an engine speed deviation to the injection command unit as a basic fuel injection amount; and a second calculation unit for outputting a fuel injection amount obtained by FF calculation based on an engine load at present of an engine to the injection command unit as a FF fuel injection amount. The fuel injection amount command value switches from a fuel injection amount calculated based on the basic fuel injection amount by the injection command unit to a fuel injection amount calculated based on a value obtained by adding the FF fuel injection amount to the basic fuel injection amount, if it is determined that a load application state has occurred in which the engine load before a prescribed time, which is not greater than a prescribed value, increases by not less than a variation threshold.

First claim

The invention claimed is:

1. An engine control device, comprising:
an injection command unit for outputting a fuel injection amount command value indicating a fuel injection amount supplied to an engine;
a first calculation unit for outputting a fuel injection amount obtained by feedback calculation based on an engine speed deviation which is a deviation between an actual engine speed and a target engine speed of the engine to the injection command unit as a basic fuel injection amount;
a second calculation unit for outputting a fuel injection amount obtained by feedforward calculation based on an engine load at present of the engine to the injection command unit as a feedforward fuel injection amount; and
a first determination unit for determining whether a load application state has occurred in which the engine load before a prescribed time, which is not greater than a prescribed value, increases by not less than a variation threshold,
wherein the engine control device is configured to switch from a normal control mode where the injection command unit outputs, as the fuel injection amount command value, a first fuel injection amount calculated based on the basic fuel injection amount to a load application control mode where the injection command unit outputs, as the fuel injection amount command value, a second fuel injection amount calculated based on a value obtained by adding the feedforward fuel injection amount to the basic fuel injection amount, if the first determination unit determines that the load application state has occurred.

2. The engine control device according to claim 1 , further comprising:
a second determination unit for determining whether at least either of a condition where the basic fuel injection amount is not less than an upper limit fuel injection amount decided from a characteristic value correlated with an air supply amount of air supplied to the engine or a condition where the actual engine speed is not less than a prescribed rotation speed is satisfied,
wherein the engine control device is configured to switch from the load application control mode to the normal control mode, if the second determination unit determines that the at least either of the conditions is satisfied under the load application control mode.

3. The engine control device according to claim 1 ,
wherein the first calculation unit is configured to maintain a feedback gain value in the feedback calculation under the load application control mode.

4. The engine control device according to claim 1 ,
wherein the first determination unit includes:
a low-load determination unit for determining whether the engine load before the prescribed time is not greater than the prescribed value; and
a load increase determination unit for determining whether an increase in the engine load is not less than the variation threshold,

wherein the load increase determination unit is configured to determine that the increase in the engine load is not less than the variation threshold, if at least one load increase condition is fully satisfied, and
wherein the load increase condition includes a first load increase condition where a first load deviation which is a deviation between the engine load at present and the engine load before the prescribed time relative to the engine load at present is not less than the variation threshold.

5. The engine control device according to claim 1 ,
wherein the first determination unit includes:
a low-load determination unit for determining whether the engine load before the prescribed time is not greater than the prescribed value; and
a load increase determination unit for determining whether an increase in the engine load is not less than the variation threshold,

wherein the load increase determination unit is configured to determine that the increase in the engine load is not less than the variation threshold, if at least one load increase condition is fully satisfied, and
wherein the load increase condition includes a second load increase condition where a derivative value of the engine load at present is not less than a derivative threshold.

6. The engine control device according to claim 4 ,
wherein the load increase condition includes a third load increase condition where a second load deviation which is a deviation between the engine load at present and a processed engine load obtained by low-pass filtering the engine load before the prescribed time is not less than the variation threshold.

7. The engine control device according to claim 4 ,
wherein the load increase condition includes a fourth load increase condition where the engine speed deviation is not greater than a first rotation speed threshold.

8. The engine control device according to claim 4 ,
wherein the low-load determination unit is configured to determine that the engine load before the prescribed time is not greater than the prescribed value, if the engine load before the prescribed time is not greater than the prescribed value and the actual engine speed is not greater than a second rotation speed threshold.

9. The engine control device according to claim 1 ,
wherein the second calculation unit is configured to output, as the feedforward fuel injection amount, a fuel injection amount obtained based on the engine load at present and association data which is data referenced to at a rated engine load of the engine and associates the engine load with the fuel injection amount.

10. The engine control device according to claim 1 ,
wherein the first calculation unit is configured to:
output, as the basic fuel injection amount, the fuel injection amount obtained by the feedback calculation based on the engine speed deviation, under the normal control mode; and
output, as the basic fuel injection amount, the fuel injection amount obtained by the feedback calculation based on a deviation between an actual engine load and a target engine load of the engine, under the load application control mode.

11. An engine control system, comprising:
the engine;
a rotation speed sensor for detecting a rotation speed of the engine;
a load sensor for detecting the engine load of the engine;
the engine control device according to claim 1 for acquiring a detection result of each of the rotation speed sensor and the load sensor; and
a fuel injection part disposed in the engine and configured to inject fuel in accordance with the fuel injection amount command value output from the injection command unit of the engine control device.

12. An engine control program configured to cause an engine device which is a computer to execute:
an injection command step of outputting a fuel injection amount command value supplied to an engine;
a first calculation step of outputting, as a basic fuel injection amount acquired in the injection command step, a fuel injection amount obtained by feedback calculation based on an engine speed deviation which is a deviation between an actual engine speed and a target engine speed of the engine;
a second calculation step of outputting, as a feedforward fuel injection amount acquired in the injection command step, a fuel injection amount obtained by feedforward calculation based on an engine load at present of the engine; and
a first determination step of determining whether a load application state has occurred in which the engine load before a prescribed time, which is not greater than a prescribed value, increases by not less than a variation threshold,
wherein the engine control program causes the engine device to switch from a normal control mode where a first fuel injection amount calculated based on the basic fuel injection amount is outp

Assignees

• Mitsubishi Heavy Ind Engine & Turbocharger Ltd

Inventors

• Takayanagi Ko
• Kitamura Yosuke
• Kuramoto Takayoshi
• Sase Ryo

Classifications

• F02D2200/101

  Engine speed · CPC title

• F02D2200/1002

  Output torque · CPC title

• F02D2041/141

  using a feed-forward control element · CPC title

• F02D2041/1409

  using at least a proportional, integral or derivative controller · CPC title

• F02D41/1401

  characterised by the control or regulation method (F02D41/1473, F02D41/1477 take precedence) · CPC title