CN-122014397-A - Cooling liquid temperature ultra-high limit fault optimization strategy

CN122014397ACN 122014397 ACN122014397 ACN 122014397ACN-122014397-A

Abstract

The invention discloses a cooling liquid temperature ultra-high limit fault optimization strategy, relates to a cooling liquid control technology, and solves the technical problems of high fault misjudgment rate, high fault missed judgment risk and poor flexibility of a fault diagnosis strategy with a single temperature threshold. The strategy comprises the steps of collecting engine operation parameters, determining the switching state of a multi-state switch according to the engine operation parameters, and setting a water temperature limit value according to the switching state of the multi-state switch. The invention solves the technical problem of adapting a single threshold to multiple working conditions and improves the accuracy of judging the working conditions of the engine.

Inventors

WEI YINGYING
LI WENJIE
LIAO HUAXIN
CAI WEI
LIU JUN
LI JUSHENG
GUAN YIQUAN
LIU XIAOYONG
LIANG WEI

Assignees

广西玉柴机器股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260228

Claims (5)

1. The cooling liquid temperature ultra-high limit fault optimization strategy is characterized by comprising the steps of collecting engine operation parameters, setting triggering conditions of a multi-state switch according to the engine operation parameters, setting a switch state of the multi-state switch to be an on state when the triggering conditions of the multi-state switch meet preset on requirements, setting the switch state of the multi-state switch to be an off state when the triggering conditions of the multi-state switch do not meet the on requirements, and setting a water temperature limit value according to the switch state of the multi-state switch.
2. The ultra-high coolant temperature limit fault optimization strategy according to claim 1, wherein the engine operating parameters include engine real-time load, real-time vehicle speed, engine operating state, fan operating state, and coolant temperature; the triggering conditions comprise a first triggering condition, a second triggering condition and a third triggering condition, wherein the first triggering condition is whether the running state of the engine is a stop state or not; Comparing the real-time vehicle speed with a vehicle speed limit value, wherein the second triggering condition is whether the real-time vehicle speed is smaller than the vehicle speed limit value and the vehicle speed sensor is in a fault state; Comparing the cooling liquid temperature with a fan starting temperature threshold, wherein the third triggering condition is whether the cooling liquid temperature is greater than or equal to the fan starting temperature threshold and whether the fan is in an inactive state; And comparing the real-time load of the engine with a real-time load lower limit value of the engine, wherein the fourth triggering condition is whether the real-time vehicle speed is smaller than a vehicle speed limit value, a vehicle speed sensor is in a fault state, and the real-time load of the engine is larger than the real-time load lower limit value of the engine.
3. The coolant ultra-high temperature fault optimization strategy according to claim 2, wherein the turn-on requirements include a first turn-on requirement, a second turn-on requirement, a third turn-on requirement, and a fourth turn-on requirement, The first opening requirement is that the running state of the engine is a stop state; the second opening request is a fault-free state of a vehicle speed sensor with the real-time vehicle speed smaller than the vehicle speed limit value; the third starting requirement is that the temperature of the cooling liquid is greater than or equal to a fan starting temperature threshold value and the fan is in a non-working state; the fourth opening requirement is that the real-time vehicle speed is smaller than the vehicle speed limit value, the vehicle speed sensor has no fault state, and the real-time load of the engine is larger than the real-time load lower limit value of the engine; When the first opening requirement, the second opening requirement, the third opening requirement or the fourth opening requirement are met, the switch state of the multi-state switch is set to be in an opening state, and otherwise, the switch state of the multi-state switch is set to be in a closing state.
4. The coolant ultra-high temperature fault optimization strategy according to claim 3, wherein the water temperature limit is selected based on the on-off state by, The water temperature limit comprises a first water temperature limit, a second water temperature limit, a third water temperature limit, a fourth water temperature limit, a fifth water temperature limit and a sixth water temperature limit; when the switch state of the multi-position switch is an on state, selecting the second water temperature limit value, the fourth water temperature limit value and the sixth water temperature limit value; and when the switch state of the multi-position switch is in an off state, selecting the first water temperature limit value, the third water temperature limit value and the fifth water temperature limit value.
5. The ultra-high coolant temperature fault optimization strategy of claim 2, wherein a fault alarm is triggered when the coolant temperature is greater than or equal to a fan start temperature threshold, and wherein the fault alarm is released when the coolant temperature is less than the fan start temperature threshold.

Description

Cooling liquid temperature ultra-high limit fault optimization strategy Technical Field The invention relates to a cooling liquid control technology, in particular to a cooling liquid temperature ultra-high limit fault optimization strategy. Background In the field of engine control systems, coolant temperature is a core monitoring parameter that ensures safe and stable operation of an engine. When the temperature of the cooling liquid exceeds a safety threshold, the control system needs to trigger an alarm or protection strategy to avoid serious faults of cylinder pulling, tile holding and the like of the engine due to overheating. At present, a fault diagnosis strategy with a unified temperature threshold is adopted, namely, a fixed alarm threshold and a fixed protection threshold are set for the coolant ultrahigh-limit fault, and the actual running conditions of the engine are not distinguished. Under different working conditions, the reasonable upper limit of the temperature of the cooling liquid has obvious difference that the cooling effect can be enhanced by the windward generated by the running of the vehicle during normal running, the reasonable upper limit of the temperature is lower, the cooling liquid is reversely filled by the residual heat of the cylinder body due to the stopping of the water pump during the shutdown and backheating stage, the temperature can be quickly flushed, the cooling liquid is cooled in an idle working condition without the aid of the running wind, the reasonable upper limit of the temperature is higher than that of the normal running working condition, the fuel burning heat generation amount of the engine is large under the high-load working conditions such as climbing, getting rid of the trapping and the like, the problem of insufficient air quantity of a fan possibly occurs, the reasonable upper limit of the temperature needs to be further improved, the heat dissipation capacity is greatly reduced when the fan does not work, and the temperature threshold needs to be adapted to a special scene without forced heat dissipation. With strict implementation of national six-emission regulations and improvement of requirements of users on engine operation reliability and fault diagnosis accuracy, the traditional single-threshold diagnosis strategy is difficult to meet actual application requirements. The prior art has the following disadvantages: (1) High fault misjudgment rate When the unified temperature threshold is adopted, normal temperature rise under working conditions such as shutdown backheating, idling and the like can be misjudged as a fault, so that fault alarm is frequently triggered, normal use of a user is interfered, and meanwhile, the workload of after-sale investigation is increased. (2) The risk of failure missed judgment is large Under the working conditions of climbing, getting rid of poverty, the fan does not work, and the like, the reasonable upper limit of the temperature of the cooling liquid is higher than the conventional threshold value, if the fixed standard is still used, the situation that the actual temperature is close to a dangerous value but the system does not trigger an alarm can occur, and the hidden trouble of overheat damage of the engine exists. (3) Poor diagnostic strategy flexibility The existing strategy can not dynamically adjust the threshold according to the running state of the engine, has weak suitability, and is difficult to meet the requirements of multi-scene and high-precision fault diagnosis of the national six controllers. Disclosure of Invention The technical problems to be solved by the invention are to provide a cooling liquid temperature ultra-high limit fault optimization strategy aiming at the defects of the prior art, and the prior single temperature threshold fault diagnosis strategy has the technical problems of high fault misjudgment rate, large fault missed judgment risk and poor flexibility. The cooling liquid temperature ultra-high limit fault optimization strategy comprises the steps of collecting engine operation parameters, setting triggering conditions of a multi-state switch according to the engine operation parameters, setting the switching state of the multi-state switch to be in an on state when the triggering conditions of the multi-state switch meet preset on requirements, setting the switching state of the multi-state switch to be in an off state when the triggering conditions of the multi-state switch do not meet the on requirements, and setting water temperature limit values according to the switching state of the multi-state switch. The engine operation parameters comprise the real-time load of the engine, the real-time speed of the engine, the operation state of the engine, the working state of the fan and the temperature of cooling liquid; the triggering conditions comprise a first triggering condition, a second triggering condition and a third triggering condition, wherein the first triggeri