Speed control method based on tsc1 rotation speed request

Abstract

The application discloses a TSC1 rotating speed request-based speed regulation control method, wherein when a whole machine controller VCU sends a TSC1 rotating speed request to an engine controller ECU through a CAN bus, a speed regulation rate (Droop) request is synchronously sent, the engine controller calculates a corresponding speed regulation target rotating speed according to the received rotating speed request information and the speed regulation rate request information and an engine working load rate in the controller in real time, so that the TSC1 speed regulation control is realized. The method solves the defect that the engine has no speed regulation rate control when the main machine factory (OEM) of engineering mechanical equipment uses the TSC1 control mode to request the engine rotating speed.

Description

Technical Field

[0001] This invention belongs to the field of energy-saving matching technology of diesel engines for engineering machinery applications, and relates to a method for speed regulation control of diesel engine operating speed, specifically a speed regulation control method based on TSC1 speed request. Background Technology

[0002] Off-road construction machinery such as excavators, rotary drilling rigs, and air compressors are characterized by fixed-gear operation. During operation, load changes frequently, resulting in significant speed fluctuations. Therefore, continuous speed control is typically required to maintain stable operating speeds. In continuous speed control, the speed regulation rate is a crucial concept. It refers to the percentage deviation of the engine's stable speed under full load from its stable speed under no-load conditions. The speed regulation rate represents the engine's ability to overcome speed fluctuations when external load changes. A higher rate allows for greater speed deviation, resulting in gentler engine speed control and lower fuel consumption and noise levels. However, an excessively high rate regulation rate can also lead to significant speed drops, impacting work efficiency. Matching an appropriate engine speed regulation rate to the speed control based on the application requirements of the construction machinery helps further reduce fuel consumption.

[0003] Currently, there are two main control methods for construction machinery vehicles to request operating speed from the engine: one is the throttle opening control method, commonly known as the throttle percentage control method, and the other is the torque speed control method, commonly known as the TSC1 control method.

[0004] Throttle opening control is the most traditional and widely used control method. It can be requested via hard wire or by sending a message via the CAN bus. Under this control method, the engine ECU will control the output engine speed corresponding to the throttle opening percentage requested by the whole machine. At the same time, the whole machine can synchronously request a suitable droop from the engine to participate in speed control, such as 6%, 8%, 12%, etc., to reduce fuel consumption. The control strategy is relatively mature.

[0005] The second control method, TSC1 control, has become increasingly widely used in recent years, especially in excavator applications, where many OEMs have chosen to use TSC1 speed control. TSC1 control sends speed requests directly through the bus, eliminating the need for OEMs to consider the correlation between speed and throttle opening, thus making the request simpler and more direct.

[0006] However, the TSC1 speed can only be requested via the CAN bus. According to publicly available information, no diesel engine manufacturer has yet provided a speed regulation control strategy and algorithm in its controller calibration software to realize TSC1 speed regulation calculation. In other words, when TSC1 requests speed, speed regulation control cannot be achieved. This is a shortcoming for engineering machinery applications that require energy-saving matching using different speed regulation rates. Summary of the Invention

[0007] To address the shortcoming of existing technologies where no diesel engine manufacturer provides a droop control strategy and algorithm in its controller calibration software to achieve TSC1 speed regulation calculation, i.e., when TSC1 requests speed, droop control cannot be implemented, this invention provides a speed regulation control method based on TSC1 speed request control, offering a new speed regulation control strategy and algorithm. When the engine control unit (VCU) sends a TSC1 speed request to the engine control unit (ECU) via the CAN bus, it simultaneously sends a droop request. Based on the received speed request information and droop request information, the engine control unit internally calculates the corresponding target speed in real time according to the engine workload, thereby achieving TSC1 speed regulation control. This method solves the problem of the lack of droop control when OEMs request engine speed using the TSC1 control method.

[0008] The objective of this invention is achieved through the following technical solution:

[0009] The speed control method based on TSC1 speed request is also a speed control strategy and algorithm for engineering machinery based on TSC1 speed request, which includes the following steps:

[0010] 1) The "TCS1 speed regulation control" function has been developed and completed in the engine ECU control calibration software. The algorithm for the TSC1 speed regulation target speed is as follows:

[0011] TSC1 speed regulation target speed = TSC1 requested speed - (TSC1 requested speed - TSC1 requested speed / (1 + requested speed regulation rate)) × engine workload rate

[0012] When the engine workload is 0%, that is, when there is no speed regulation under no-load conditions, the target speed for speed regulation is equal to the speed requested by TSC1 itself.

[0013] When the engine working load rate is 100%, that is, when the speed is adjusted at full load, the target speed is equal to the lowest deviation speed allowed under the current requested speed adjustment rate.

[0014] 2) During engine operation, the vehicle control unit (VCU) sends TSC1 speed request messages and Droop speed adjustment request messages to the engine control unit (ECU) in real time via the CAN bus according to matching requirements.

[0015] 3) The engine controller reads the current engine load rate in real time;

[0016] 4) The engine controller calculates the target speed of TSC1 in real time based on the received TSC1 request speed, request speed information and the current engine workload, and performs speed control.

[0017] Furthermore, in step 2), the TSC1 speed request message is sent to the engine controller (ECU) in real time via the CAN bus, wherein the message is in accordance with the J1939 protocol, PGN 0, SPN 898 specification.

[0018] Furthermore, in step 2), the Drop rate request message is in accordance with the J1939 protocol, PGN64971, and SPN 2881 specifications.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] The speed control method based on TSC1 speed request described in this invention enables the diesel engine of construction machinery to perform speed regulation control in TSC1 speed control mode, allowing the engine to operate in a better fuel-efficient range and meeting the optimal fuel economy requirements of construction machinery. Comparative verification shows that compared to the traditional TCS1 non-speed regulation control method, the TSC1 speed regulation control strategy provided by this invention reduces fuel consumption of tracked excavators operating in commonly used gears by 5%-7% under speed regulation control of 8%-12%, demonstrating significant effectiveness. Attached Figure Description

[0021] Figure 1 This is a comparison chart showing the reduction in working fuel consumption before and after applying the TSC1 speed control strategy provided by this invention to a certain brand of 22T crawler excavator.

[0022] Figure 2 This is a logical schematic diagram of the speed control method based on TSC1 speed request described in this invention;

[0023] Figure 3 This is a flowchart illustrating the speed control method based on TSC1 speed request described in this invention. Detailed Implementation

[0024] The specific embodiments of the present invention will be further described below with reference to examples.

[0025] Example:

[0026] Taking a certain brand of 22T tracked excavator as an example, the speed control method based on TSC1 speed request includes the following steps:

[0027] 1) The "TCS1 speed regulation control" function has been developed and completed in the engine ECU control calibration software. The algorithm for the TSC1 speed regulation target speed is as follows:

[0028] TSC1 speed regulation target speed = TSC1 requested speed - (TSC1 requested speed - TSC1 requested speed / (1 + requested speed regulation rate)) × engine workload rate

[0029] When the engine workload is 0%, that is, when there is no speed regulation under no-load conditions, the target speed for speed regulation is equal to the speed requested by TSC1 itself.

[0030] When the engine working load rate is 100%, that is, when the speed is adjusted at full load, the target speed is equal to the lowest deviation speed allowed under the current requested speed adjustment rate.

[0031] 2) During engine operation, the vehicle control unit (VCU) sends TSC1 speed request messages (messages according to J1939 protocol, PGN 0, SPN 898 specifications) and Droop speed adjustment request messages (messages according to J1939 protocol, PGN 64971, SPN 2881 specifications) to the engine control unit (ECU) in real time via the CAN bus according to matching requirements.

[0032] 3) The engine controller reads the current engine load rate in real time;

[0033] 4) The engine controller calculates the target speed of TSC1 speed regulation in real time based on the received TSC1 request speed, request regulation rate information and the current engine workload rate, and performs speed regulation control.

[0034] Figure 1 This is a comparison chart showing the reduction in working fuel consumption before and after applying the TSC1 speed control strategy provided by this invention to a certain brand of 22T crawler excavator.

[0035] from Figure 1 As can be seen, taking the E8 gear as an example, in step 2), the vehicle controller (VCU) requests a TSC1 speed of 1800 rpm and a speed adjustment rate of 12%. Meanwhile, in step 3), if the engine controller reads that the current engine load rate is 80%, according to the control algorithm of this invention, the final actual TSC1 speed adjustment target control speed is 1645 rpm. Compared with the original TSC1 requested speed of 1800 rpm, the adjusted speed of 1645 rpm falls within the engine's optimal economic speed range, reducing actual fuel consumption.

[0036] Figure 2 This is a logical schematic diagram of the speed control method based on TSC1 speed request described in the embodiment;

[0037] Figure 3 This is a flowchart illustrating the speed control method based on TSC1 speed request as described in the embodiment.

[0038] Comparative example:

[0039] The existing traditional TSC1 speed regulation control method is very simple, as follows:

[0040] During engine operation, the vehicle control unit (VCU) directly sends a TSC1 speed request message (according to J1939 protocol, PGN 0, SPN 898 specification) to the engine control unit (ECU) in real time via the CAN bus. The requested speed value is the final target value. There is no speed adjustment request or calculation, and no engine workload rate reading or calculation. The TSC1 speed request is the obtained value. For example, in the 22T excavator of a certain brand mentioned in the embodiment, before applying the control strategy of this invention, in the E8 working gear, the TSC1 requested speed was 1800 rpm, and the final controlled speed was also 1800 rpm. There was no speed adjustment control throughout the entire process.

[0041] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, any improvements and changes made without departing from the inventive concept of the present invention are within the protection scope of the present invention.

Claims

1. A speed control method based on TSC1 speed request, characterized in that: Includes the following steps: 1) The "TSC1 speed regulation control" function has been developed and completed in the engine ECU control calibration software. The control algorithm for the target speed of TSC1 speed regulation is as follows: TSC1 speed regulation target speed = TSC1 requested speed - (TSC1 requested speed - TSC1 requested speed / (1 + requested speed regulation rate)) × engine duty rate; When the engine workload is 0%, that is, when there is no speed regulation under no-load conditions, the target speed for speed regulation is equal to the speed requested by TSC1 itself. When the engine working load rate is 100%, that is, when the speed is adjusted at full load, the target speed is equal to the lowest deviation speed allowed under the current requested speed adjustment rate. 2) During engine operation, the vehicle control unit (VCU) sends TSC1 speed request messages and Droop speed adjustment request messages to the engine control unit (ECU) in real time via the CAN bus according to matching requirements. 3) The engine controller reads the current engine load rate in real time; 4) The engine controller calculates the target speed of TSC1 speed regulation in real time based on the received TSC1 request speed, request speed regulation information and the current engine workload, and performs speed regulation control.

2. The speed control method based on TSC1 speed request according to claim 1, characterized in that: In step 2), a TSC1 speed request message is sent to the engine controller in real time via the CAN bus, wherein the message is in accordance with the J1939 protocol, PGN 0, SPN 898 specification.

3. The speed control method based on TSC1 speed request according to claim 1, characterized in that: In step 2), the Drop rate request message is in accordance with the J1939 protocol, PGN 64971, SPN 2881 specifications.

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