A fuel-saving test method and recording medium for an electronically controlled generator

Abstract

The present invention belongs to the technical field of engine testing, and particularly relates to a fuel-saving test method for an electronically controlled generator, including obtaining basic data of a vehicle fuel consumption cycle test working condition, inputting relevant data into an engine bench test control system, so that the engine bench test is consistent with the working condition of the vehicle fuel consumption cycle test; arranging the main electrical equipment of the vehicle on the engine test bench to simulate the power consumption state of the vehicle; measuring the fuel consumption of the electronically controlled generator working in a mechanical mode on the engine bench; then measuring the fuel consumption of the electronically controlled generator configured under various other control strategies and making a comparison, and obtaining the fuel saving rate of the electronically controlled generator under different control strategies relative to the generator in the mechanical mode during the vehicle fuel consumption cycle test process. The present invention also provides a medium storing the method program. The present invention overcomes the problem that it is difficult to accurately measure a small fuel saving rate due to human error on the bench, and is suitable for engine bench fuel saving testing.

Description

Technical Field

[0001] The invention belongs to the technical field of engine test and discloses a fuel-saving test method for an electronically controlled generator and a recording medium storing a program capable of executing the method. Background Art

[0002] The fuel consumption of a vehicle is an economic technical indicator of the vehicle. Lower fuel consumption is beneficial to environmental protection and energy conservation, and can also better reflect the competitiveness of the vehicle product. At present, electronic control of engine accessories is an important technical measure for engine fuel saving. For example, the electronically controlled water pump, electronically controlled oil pump, and electronically controlled generator attached to the engine can save more fuel and reduce consumption than conventional mechanical control components.

[0003] The fuel-saving strategy of the electronically controlled generator is to monitor the temperature, current, voltage, power and other information of the car battery at any time through the battery sensor, and transmit it to the engine control unit in real time. The engine control unit makes a comprehensive judgment based on the battery status, engine operating status and other information, and controls the electronically controlled generator regulator to increase or decrease the generator output voltage. When the battery power is low, the engine control unit controls the generator to increase the output voltage to quickly charge the battery; conversely, when the battery power is high, the generator output voltage is reduced, and the engine torque output to the generator is reduced, so as to reduce fuel consumption and CO2 emissions; the charging efficiency of the electronically controlled generator to the battery is positively correlated with the output voltage of the electronically controlled generator and the speed of the engine driving the electronically controlled generator, so the consistency of the engine speed is crucial during the test process, which is also an important reason why this patent needs to convert the vehicle fuel consumption test conditions into engine bench test conditions.

[0004] However, the fuel saving rate between different control strategies of general electronically controlled generators is only less than 3% in the NEDC cycle fuel consumption of the whole vehicle or other fuel consumption regulations cycle tests such as C-WTVC. The fuel consumption measurement equipment itself will also have certain measurement errors. In addition, there are certain differences in the fuel consumption cycle conditions of the whole vehicle and the driver's braking and driving habits during each measurement. It is difficult to accurately test the fuel saving rate in such a narrow range. For example, the method based on the NEDC road cycle of the whole vehicle in the patent of announcement number CN 104964827 A: "A method for calculating the idle fuel saving rate" converts the average fuel consumption values ​​at different engine idle speeds for a long time into the NEDC cycle fuel consumption of the whole vehicle to approximate the fuel saving rate. The reason for using this method of converting fuel consumption is mainly because the fuel consumption difference at different idle speeds is small, and the idle condition accounts for a small proportion of the time in the NEDC condition. However, this method is not suitable for the condition in cities where vehicles often stop and idle due to traffic lights. Announcement No. CN 105628392 A: The method in the patent "A method for calculating the fuel saving rate of a start-stop system" is based on the NEDC road cycle. It adopts a formula and uses the vehicle NEDC measured data, calibrated theoretical fuel volume data and empirical data (idle fuel consumption correction coefficient Φn, start-up enriched fuel consumption Fstart) to calculate the fuel saving rate of the engine start-stop system. Obviously, the correction coefficient Φn is difficult to determine, and the patent does not disclose the method for determining Φn; therefore, it is also difficult to derive the accurate fuel saving rate of the NEDC operating condition. Summary of the invention

[0005] In view of the above problems, the present invention provides a fuel saving test method for an electronically controlled generator, and the specific scheme includes the following steps:

[0006] P1. Carry out a vehicle fuel consumption cycle test to obtain basic data of the vehicle fuel consumption cycle test conditions, the basic data including engine speed, engine torque, brake chamber pressure at different times under the vehicle fuel consumption cycle conditions and their corresponding relationship;

[0007] P2. Determine the braking time point, braking duration and brake chamber pressure through the curve of the brake chamber pressure changing with time;

[0008] P3. Input the braking time point, braking duration, brake chamber pressure and the basic data into the engine bench test control system, so that the engine state and brake system gas state of the engine bench test are consistent with the engine state and brake system gas state of the vehicle fuel consumption cycle test;

[0009] P4. Place the main electrical equipment of the vehicle on the engine test bench to simulate the power consumption of the vehicle;

[0010] P5. Configure the electronically controlled generator in mechanical mode during the engine bench test and measure the fuel consumption during the entire test duration;

[0011] P6. Configure the electronically controlled generator to work under different electronic control strategies in the engine bench test and measure the fuel consumption during the entire test duration;

[0012] P7. Compare the fuel consumption data under each control strategy measured in step P6 with the fuel consumption measured in step P5 to obtain the fuel saving rate of the electronically controlled generator under each control strategy relative to the mechanical generator during the vehicle fuel consumption cycle test.

[0013] The above method can better transplant the working conditions of the vehicle fuel consumption cycle test to the engine test bench through the extraction of key basic data, which is convenient for conducting fuel saving rate tests for different control strategies of the electronically controlled generator under the condition of consistent working conditions and compliance with industry testing standards.

[0014] Preferably, step P3 includes a step of using proportional-integral-differential (PID) control to achieve the consistency of the operating conditions.

[0015] This procedure for achieving consistent operating conditions uses closed-loop control. When various sensors and servo systems are sensitive, it can accurately simulate the action of the driver stepping on the brake pedal on the laboratory engine test bench to reproduce the operating conditions of the vehicle fuel consumption cycle test.

[0016] Preferably, step P3 includes a step of achieving the consistency of the working conditions by pushing the brake pedal at a uniform speed during braking.

[0017] This procedure to achieve consistent operating conditions only considers the braking point and braking duration, simplifies the braking speed to a uniform speed, reduces possible fault defects caused by too many components, and more importantly, eliminates the lag phenomenon in the closed-loop control that may cause fuel consumption deviations due to the non-coincidence of the actual pressure curves of the brake chamber in multiple tests.

[0018] Another embodiment of the present invention is to provide a non-transitory readable recording medium for storing one or more programs including a plurality of instructions. When the instructions are executed, the processing circuit will execute the above-mentioned electronically controlled generator fuel saving test method. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a diagram showing the corresponding relationship between the vehicle speed and the engine speed under the C-WTVC working condition in an embodiment of the present invention;

[0020] Figure 2 : is a diagram showing the corresponding relationship between engine speed and torque under C-WTVC working condition in an embodiment of the present invention;

[0021] Figure 3: is a graph showing the corresponding relationship between the engine speed and the brake chamber pressure under the C-WTVC working condition in an embodiment of the present invention;

[0022] Figure 4 It is a schematic diagram of the power consumption state of the whole vehicle simulated by the main power-consuming equipment arranged on the engine test bench in an embodiment of the present invention. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be described below in conjunction with the drawings in the embodiments of the present invention. The described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making innovative efforts are within the scope of protection of the present invention.

[0024] 1. Vehicle preparation before testing

[0025] Replace the electronically controlled generator on the vehicle, install a pressure sensor on the brake air chamber of the vehicle, electrically connect the controller with the electronically controlled generator, pressure sensor, relay and vehicle battery, and ensure that the controller can normally control the operation of the electronically controlled generator and read the value of the pressure sensor.

[0026] The controller drives the relay to close normally, so that the electronically controlled generator is in the working mode of a conventional mechanical generator. Before the test, make sure that the brake system air tank is full of air.

[0027] 2. Acquisition of basic data of vehicle fuel consumption cycle and recording of test parameters

[0028] There are two ways and methods to obtain the basic data of vehicle fuel consumption cycle conditions. One is to conduct a vehicle fuel consumption regulation cycle test on a vehicle rotary test bench according to the vehicle fuel consumption regulation cycle (such as NEDC, C-WTVC and other fuel consumption regulation cycles); the other is to use the actual vehicle road to collect road spectrum parameters. The road conditions can cover 40% of urban conditions, 40% of suburban or rural conditions, and 30% of high-speed conditions. The specific distribution ratio of conditions can be determined according to the application market environment of the vehicle. Which method is selected as the basic data of the vehicle fuel consumption cycle condition as the fuel saving efficiency test of different control strategies of the electronically controlled generator depends on the company's own development purpose. Therefore, the vehicle fuel consumption cycle condition scheme can be freely selected. Which method is used for road spectrum parameter collection can be applied to the subsequent scheme description of the patent of this invention; this patent simplifies the subsequent test scheme description and is unified as the vehicle C-WTVC condition fuel consumption regulation cycle.

[0029] The relay is normally closed to ensure that the electronically controlled generator is always in working condition during the vehicle hub C-WTVC operating condition fuel consumption test, that is, the electronically controlled generator is in the working mode of a conventional mechanical generator during the test.

[0030] When the C-WTVC fuel consumption regulation cycle is carried out on the vehicle's rotating hub, when the vehicle's rotating hub dynamometer enters the C-WTVC condition, the controller is triggered through the rotating hub dynamometer control system to record the pressure value of the brake air chamber pressure sensor; by monitoring the pressure value of the pressure sensor, the driver's braking point, braking duration and brake air chamber pressure (corresponding to the braking depth of the brake pedal) in the vehicle's C-WTVC condition can be known.

[0031] At the same time, the engine speed (OBD_EngineSpeed), engine torque (OBD_RealTorque) and vehicle speed (vehicle Speed) in the vehicle ECU are read and recorded at a frequency of 1Hz through the vehicle OBD terminal interface, and the engine speed parameter and engine torque parameter table of 1800s can be obtained as the operating condition of the engine test bench C-WTVC; the pressure value of the pressure sensor on the brake air chamber is superimposed on the speed and torque list of the engine C-WTVC, and the corresponding relationship between the engine speed, torque and the pressure of the brake air chamber of the brake system can be obtained.

[0032] 3. Transplantation of vehicle-to-bench operating conditions and preparation for fuel-saving test of electronically controlled generator bench

[0033] Select an industrial computer with multiple I / O ports as the engine bench test control system, and input the basic engine data of the vehicle fuel consumption cycle test conditions obtained in the above steps as well as the braking timing, braking duration and brake chamber pressure (corresponding to the braking depth of the brake pedal) information into the engine bench test control system as the basic data for the engine bench to perform C-WTVC. Any fuel-saving efficiency comparison test of the electronically controlled generator under different control strategies is carried out on this basic data.

[0034] The components related to the vehicle braking system (air dryer assembly, four-protection valve, air reservoir, brake pedal, quick release valve assembly, front / rear axle assembly, etc.) and the pedal displacement actuator (used to push the brake pedal according to the instructions issued by the control system) are arranged in the engine test room and electrically connected to the engine bench test control system.

[0035] The engine bench test control system can control the engine operation according to the working conditions introduced above, and control the brake pedal displacement actuator to push the brake pedal according to the brake air chamber pressure value. The brake pedal displacement actuator can perform PID feedback of the brake air chamber pressure signal through the brake air chamber pressure sensor, or the brake pedal displacement actuator adopts a scheme that only considers the braking time point and braking duration and simplifies the braking speed to a uniform speed (the speed of the brake pedal displacement actuator uniform speed scheme is determined by detecting the speed at which the driver steps on the brake pedal during the vehicle fuel consumption cycle and taking the average value).

[0036] 4. Engine Bench C-WTVC Fuel Consumption Test

[0037] Since the fuel consumption test of the electronically controlled generator under different control strategies cannot be completed within one day, the factors affecting the fuel consumption results need to be checked before each test.

[0038] It includes checking engine control conditions, such as engine water temperature, oil temperature, intake temperature, intake pressure, intercooler temperature, intercooler pressure, exhaust temperature, exhaust pressure, fuel consumption at rated power and other engine operating parameters to ensure that the engine status is consistent each time the engine undergoes the C-WTVC fuel consumption test; ensuring that the air tank is full during each test; checking the zero and full points of the fuel consumption meter to ensure that the zero and full point status of the fuel consumption meter are consistent each time the engine undergoes the C-WTVC fuel consumption test.

[0039] For the engine bench test corresponding to each electronically controlled generator control strategy (including mechanical mode), the C-WTVC operating condition is run continuously for no less than 3 times. After the test, the average fuel consumption of multiple C-WTVC tests is calculated as the C-WTVC test fuel consumption under the current electronically controlled generator control strategy.

[0040] Transplant the main electrical equipment of the vehicle (headlights, air conditioners, wipers, instruments, window lifts, audio, etc.) to the engine test bench, and ensure that the electrical equipment can work normally. The vehicle battery provides power for the electrical equipment.

[0041] Electronically controlled generator control strategy check: Ensure that the battery sensor can monitor the temperature, current, voltage, power and other information of the vehicle battery at any time, and transmit it to the engine control unit in real time. The engine control unit controls the generator regulator based on comprehensive judgment based on information such as the battery status and engine operating status, and implements the control strategy of increasing or decreasing the generator output voltage.

[0042] Design of vehicle electrical appliance usage scenarios: The vehicle electrical appliance usage scenarios can be divided into the following categories: spring and autumn (daytime and nighttime), summer (daytime and nighttime), sunny and rainy days, and comprehensive scenarios; auxiliary electrical equipment such as window lifters and audio systems do not have high power and do not need to be tested during the test; the usage scenarios of other electrical equipment can be set by referring to the table below. Comprehensive scenarios simulate complex electrical usage scenarios and can be designed according to the usage scenarios of the vehicle electrical appliances.

[0043]

[0044] For the use scenarios of electrical appliances, it is necessary to compare the fuel efficiency of electronically controlled generators and traditional generators in the same use scenario. It is necessary to first conduct fuel consumption tests of traditional generators in different use scenarios, and then conduct fuel consumption tests of electronically controlled generators in different use scenarios. As shown in the following table.

[0045]

[0046]

[0047] Engine bench C-WTVC fuel consumption test and requirements: Before the test, configure the engine test conditions according to the generator and electrical appliance usage scenarios in the above table to ensure the normal operation of the electrical appliances and the consistency of the battery power of the vehicle before each test. Each engine bench C-WTVC runs continuously for no less than 3 times. After the test, the current fuel consumption of each engine bench C-WTVC test is integrated, and the average fuel consumption of multiple C-WTVC tests is calculated as the current C-WTVC test fuel consumption. That is, the current single C-WTVC test fuel consumption S'=S1'+S2'+S3'+…+S1800', as shown in the following table; the arithmetic average of multiple C-WTVC test fuel consumption values ​​is the C-WTVC test fuel consumption of the current test.

[0048] Time(s) OBD_EngineSpeed(rpm) OBD_RealTorque(Nm) Engine fuel consumption (g / s) 1 750 9.0 <![CDATA[S1’]]> 2 749 9.0 <![CDATA[S2’]]> 3 748 9.0 <![CDATA[S3’]]> 4 719 21.6 <![CDATA[S4’]]> 5 696 42.3 <![CDATA[S5’]]> 6 750 108.0 <![CDATA[S6’]]> … … … … … … … … 1797 752 0.0 <![CDATA[S 1797 ’]]> 1798 749 9.0 <![CDATA[S 1798 ’]]> 1799 750 9.0 <![CDATA[S 1799 ’]]> 1800 750 9.0 <![CDATA[S 1800 ’]]>

[0049] By comparing the fuel consumption obtained under different control strategies of the electronically controlled generator with the fuel consumption obtained under traditional mechanical control, the actual fuel saving rate excluding human factors can be calculated.

[0050] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computers, available storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer usable program codes.

[0051] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0052] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0053] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0054] Compiling the above method steps into a program and then storing it in a hard disk or other non-transitory storage medium constitutes the technical solution of "a non-transitory readable recording medium" of the present invention.

[0055] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A fuel-saving test method for an electronically controlled generator, characterized in that The following steps are involved: P1. Carry out a vehicle fuel consumption cycle test to obtain basic data of the vehicle fuel consumption cycle test conditions, the basic data including engine speed, engine torque, brake chamber pressure at different times and their corresponding relationships; P2. Determine the braking time, braking duration and braking air consumption by the change of the pressure of the brake chamber over time; P3. Input the braking time point, braking duration, braking gas consumption and the basic data into the engine bench test control system so that the engine bench test is consistent with the vehicle fuel consumption cycle test conditions; P4. Place the main electrical equipment of the vehicle on the engine test bench to simulate the power consumption of the vehicle; P5. Configure the electronically controlled generator in mechanical mode during the engine bench test and measure the fuel consumption during the entire test duration; P6. Configure the electronically controlled generator to work under different electronic control strategies in the engine bench test and measure the fuel consumption during the entire test duration; P7. Compare the fuel consumption data under each control strategy measured in step P6 with the fuel consumption measured in step P5 to obtain the fuel saving rate of the electronically controlled generator under each control strategy relative to the mechanical generator during the vehicle fuel consumption cycle test.

2. A fuel saving test method for an electronically controlled generator as claimed in claim 1, characterized in that Step P3 includes the step of controlling the brake pedal using a proportional-integral-differential (PID) control method to achieve the consistent working conditions.

3. A fuel saving test method for an electronically controlled generator as claimed in claim 1, characterized in that Step P3 includes the step of controlling the brake pedal to achieve the consistent working condition by pushing the brake pedal at a constant speed during braking.

4. A non-transitory readable recording medium for storing one or more programs including a plurality of instructions, characterized in that: When the instruction is executed, the processing circuit will be caused to execute the fuel-saving test method for an electronically controlled generator according to any one of claims 1 to 3.

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