Electrical system of unmanned aerial vehicle carburetor compatible electronic fuel injection engine test bench

Abstract

The invention discloses an electrical system of an unmanned aerial vehicle carburetor compatible electronic fuel injection engine test bench, which comprises a power supply module, a sensor module and a main control module, and is characterized in that the sensor module comprises a torque rotating speed sensor, an oil consumption sensor and a rail pressure sensor, and the main control module comprises a control unit, a data acquisition unit and a data processing and drawing unit; the data acquisition unit is in communication connection with the sensor module and a control unit of an engine to be detected, and is used for receiving detection data of the sensor module and control data transmitted by the control unit and transmitting the detection data and the control data to the data processing and drawing unit; the data processing and drawing unit calculates the power of the engine to be detected according to the received detection data and control data, calculates the oil consumption of the electronic fuel injection engine, and draws a power rotating speed curve, a torque rotating speed curve and an oil consumption rotating speed curve; the engine testing device can be used for testing a carburetor engine and also can be used for testing an electronic fuel injection engine, the engine testing efficiency can be improved, and the cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of aircraft component testing, in particular to an electrical system of a UAV carburetor-compatible electronic fuel injection engine test bench. Background Art

[0002] The rapid development of UAV technology has made UAVs increasingly widely used in many fields. As the key power component of UAVs, the performance test of the engine is crucial. At present, the oil power source of UAVs is generally divided into carburetor engines and electronic fuel injection engines according to the different engine starting methods.

[0003] Carbureted engines use carburetors to mix fuel and air, and their working principle is based on the pressure difference in fluid mechanics. Electronic fuel injection engines rely on electronically controlled fuel injection systems, which collect various operating parameters of the engine, such as air flow, crankshaft position, temperature, etc., through multiple sensors, and then the electronic control unit (ECU) accurately controls the injection time and amount of the injector according to these parameters.

[0004] The electrical systems of UAV engine test benches on the current market are mostly designed for a single type of engine and cannot meet the testing requirements of carburetor engines and electronic fuel injection engines at the same time. This means that when testing UAV engines, if the UAV is equipped with both types of engines, different test benches need to be used, which not only increases the testing cost and time, but also reduces the testing efficiency. Moreover, for some small UAV R&D companies or maintenance organizations, purchasing multiple different types of test benches is a heavy burden. Therefore, it is of great practical significance to develop an electrical system for a test bench that is compatible with UAV carburetor engines and electronic fuel injection engines. Summary of the invention

[0005] The purpose of the present invention is to provide an electrical system for a UAV carburetor-compatible electronic fuel injection engine test bench, aiming to improve the problem that the electrical system of the existing UAV engine test bench is designed for a single type of engine and cannot meet the testing requirements of both carburetor engines and electronic fuel injection engines at the same time.

[0006] The present invention is achieved in that: An electrical system of a UAV carburetor-compatible electronic fuel injection engine test bench includes a power module and also includes: The sensor module includes a torque and speed sensor, a fuel consumption sensor and a rail pressure sensor; the torque and speed sensor is used to measure the torque and speed of the output shaft of the engine to be tested, the fuel consumption sensor is used to measure the fuel consumption of the carburetor engine, and the rail pressure sensor is used to measure the pressure in the fuel rail of the electronic fuel injection engine; A main control module, comprising a control unit, a data acquisition unit, and a data processing and drawing unit; the control unit is electrically connected to the engine to be tested, and is used to control the start and stop of the engine to be tested; the data acquisition unit is communicatively connected to the sensor module and the control unit of the engine to be tested, and is used to receive the detection data of the sensor module and the control data of the control unit, and transmit them to the data processing and drawing unit; wherein the data processing and drawing unit is used to calculate the power and fuel consumption of the engine to be tested according to the received detection data and control data, and draw a speed curve; wherein the speed curve includes a power speed curve, a torque speed curve, and a fuel consumption speed curve; The display module is connected to the main control module for displaying the speed curve drawn by the data processing and drawing unit.

[0007] Furthermore, the power supply module includes an air switch and a switching power supply; the input end of the air switch is electrically connected to the external power supply, the output end of the air switch is electrically connected to the input end of the switching power supply, and the output end of the switching power supply is electrically connected to the sensor module and the main control module.

[0008] Further, it also includes a switch relay; The control unit is electrically connected to the engine to be tested via a switch relay; The switch relay includes a start relay and a flameout relay.

[0009] Furthermore, the data processing and drawing unit calculates the power of the engine to be tested by a first formula; the first formula is as follows: P = T × n ÷ 9549; Wherein, P is the power of the engine to be tested, T is the torque detected by the torque speed sensor, and n is the speed detected by the torque speed sensor.

[0010] Furthermore, the data processing and mapping unit is used to determine the fuel consumption per unit time of the electronic fuel injection engine, including: The second formula is used to obtain the single fuel mass of a single fuel injection of the electronic fuel injection engine; The fuel consumption per unit time of the electronic fuel injection engine is calculated using the third formula based on the single fuel mass; Among them, the second formula is as follows: 2ρP0=[m÷(b×A×t)] 2 ; The third formula is as follows: M = m × N; Wherein, P0 is the rail pressure detected by the rail pressure sensor, t is the injection pulse width of the electronic fuel injection engine transmitted from the control unit of the electronic fuel injection engine to the data acquisition unit, N is the number of injections of the electronic fuel injection engine per unit time, b is the flow coefficient of the fuel injection nozzle of the electronic fuel injection engine, A is the cross-sectional area of ​​the fuel injection nozzle, ρ is the fuel density, m is the single fuel mass of a single injection of the electronic fuel injection engine, and M is the fuel consumption of the electronic fuel injection engine per unit time.

[0011] Furthermore, the sensor module also includes a strain gauge torque sensor and a Hall effect speed sensor; The strain gauge torque sensor is installed on the output shaft of the engine to be tested, and is used to detect the torque of the engine to be tested; The Hall effect speed sensor is mounted on the crankshaft of the engine to be tested and is used to detect the speed of the engine to be tested.

[0012] Further, the data processing and drawing unit is communicatively connected with an alarm; Before drawing the speed curve of the engine to be tested, the data processing and drawing unit first checks the torque and speed based on the checking rules; wherein the checking rules include: When |T1-T2|÷T1×100%≤K1% and |T1-T2|÷T2×100%≤K1%, the torque check is qualified; When |n1-n2|÷n1×100%≤K2% and |n1-n2|÷n2×100%≤K2%, the speed calibration is qualified; Wherein, T1 is the torque detected by the torque speed sensor, T2 is the torque detected by the strain gauge torque sensor, n1 is the speed detected by the torque speed sensor, n2 is the speed detected by the Hall effect speed sensor, K1 and K2 are the first verification threshold and the second verification threshold, 0.5≤K1≤2, 0.5≤K2≤2; When the torque and speed are calibrated to be qualified, the data processing and drawing unit draws the speed curve of the engine to be tested; otherwise, the data processing and drawing unit sends an abnormal signal to the alarm to inform the staff that the detection data is abnormal.

[0013] Furthermore, the sensor module also includes a temperature sensor; The temperature sensors include an intake temperature sensor for detecting the intake temperature of the engine to be tested, an exhaust temperature sensor for detecting the exhaust temperature of the engine to be tested, and a coolant temperature sensor for detecting the coolant temperature of the engine to be tested.

[0014] Furthermore, it also includes: the data acquisition unit and the data processing and drawing unit are electrically connected to a coolant circulation system; the coolant circulation system includes a compressor and an electric energy meter for detecting the power consumption of the compressor; The data processing and drawing unit calculates the transferred heat during the test of the engine under test by a fourth formula; the fourth formula is as follows: Q = (W × η + c × m0 × ΔT) × b; Wherein, Q is the transferred heat during the test of the engine to be tested, W is the power consumption of the compressor detected by the electric energy meter during the test, η is the mechanical efficiency of the compressor, c is the specific heat capacity of the coolant, m0 is the total mass of the coolant in the coolant circulation system, η, c and m0 are pre-measured before the test and stored in the data acquisition unit; ΔT=T2-T1, is the temperature difference transmitted from the coolant temperature sensor to the data acquisition unit during the test, T1 is the temperature data transmitted from the coolant temperature sensor to the data acquisition unit before the start of the test, and T2 is the temperature data transmitted from the coolant temperature sensor to the data acquisition unit in real time during the test; b is the ambient temperature adjustment coefficient; When |Q-Q0|÷Q×100%>K3%, the data processing and drawing unit sends an abnormal signal to the alarm to notify the staff to detect the engine thermal load condition; among them, Q0 is the heat transfer threshold, K3 is the third verification threshold, 5≤K3≤10.

[0015] Furthermore, the sensor module also includes a pressure sensor installed on the engine intake duct for detecting intake pressure; The data acquisition unit receives the pressure data detected by the pressure sensor and transmits it to the data processing and drawing unit; The data processing and drawing unit draws a time intake pressure curve and a time speed curve according to the received pressure data and the speed of the engine to be tested; The data processing and mapping unit compares the received pressure data with the intake pressure threshold at the same time. When |F-F0|÷F×100%>K4%, the data processing and mapping unit sends an abnormal signal to the alarm to notify the staff that the engine has intake pressure distortion; wherein F is the pressure data, F0 is the intake pressure threshold, K4 is the fourth verification threshold, and 5≤K4≤20.

[0016] Compared with the prior art, the present invention has the following beneficial effects: the present invention can be used for testing both UAV carburetor engines and UAV electronic fuel injection engines, solving the problem that the electrical system of the existing UAV engine test bench cannot simultaneously meet the testing requirements of carburetor engines and electronic fuel injection engines. Other advantages of the present invention are described in the subsequent description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural block diagram of the electrical system of the UAV carburetor compatible electronic fuel injection engine test bench provided by the present invention; Figure 2 It is a structural schematic diagram of the sensor module provided by the present invention. DETAILED DESCRIPTION

[0018] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0019] The following is a further description with reference to the accompanying drawings and specific embodiments: like Figure 1 As shown, an electrical system of a UAV carburetor compatible with an electronic fuel injection engine test bench includes a power module, a sensor module, a main control module, a display module, a switch relay and an alarm. The power module includes an air switch and a switch power supply. The input end of the air switch is electrically connected to an external power supply, the output end of the air switch is electrically connected to the input end of the switch power supply, the output end of the switch power supply is electrically connected to the sensor module, the main control module and the switch relay, and the switch power supply supplies power to the sensor module, the main control module and the switch relay. The switch relay includes a start relay and a flameout relay. The main control module includes a control unit, a storage unit, an input unit, a data acquisition unit and a data processing and drawing unit. The control unit of the main control module is electrically connected to the engine to be tested through a switch relay to control the start and stop of the engine to be tested. The input unit includes a mouse, a keyboard, a touch screen, a SUB interface, etc. The alarm is connected to the data processing and drawing unit in communication and gives an alarm when an abnormal signal is received.

[0020] like Figure 1 and Figure 2As shown, the sensor module includes a torque speed sensor, a fuel consumption sensor and a rail pressure sensor. The torque speed sensor is installed between the output shaft of the engine to be tested and the load, and is used to measure the torque and speed of the output shaft of the engine to be tested. The fuel consumption sensor is used to measure the fuel consumption of the carburetor engine. The fuel consumption of the electronic fuel injection engine is calculated by an indirect measurement method. To calculate the fuel consumption of the electronic fuel injection engine, it is necessary to measure the pressure in the fuel rail of the electronic fuel injection engine, and the pressure is measured by the rail pressure sensor. The data acquisition unit of the main control module is communicatively connected to each sensor of the sensor module and the control unit of the engine to be tested, and is used to receive the detection data of the sensor module and the control data transmitted by the control unit, and transmit the received detection data and control data to the data processing and drawing unit. The data processing and drawing unit calculates the power and fuel consumption of the engine to be tested based on the received detection data and control data, and draws a speed curve, including a power speed curve, a torque speed curve and a fuel consumption speed curve. The display module can use an ordinary display screen with only a display function, or a touch display screen. The display module is communicatively connected to the main control module, and is used to display the speed curve drawn by the data processing and drawing unit for viewing by the staff.

[0021] Drawing the power-speed curve requires the speed and power of the engine to be tested. The speed can be directly measured by the torque-speed sensor, and the power is calculated, as follows: the torque-speed sensor measures the torque and speed of the output shaft of the engine to be tested, the data acquisition unit receives the torque and speed measured by the torque-speed sensor, and transmits them to the data processing and drawing unit, and the data processing and drawing unit calculates the power of the engine to be tested by the first formula. The first formula is as follows: P = T × n ÷ 9549; Wherein, P is the power of the engine to be tested, T is the torque detected by the torque speed sensor, and n is the speed detected by the torque speed sensor.

[0022] The fuel consumption speed curve requires the speed and fuel consumption of the electronic fuel injection engine. The speed can be directly measured by the torque speed sensor. For a carburetor engine, the fuel consumption data can be directly measured by the fuel consumption sensor. For an electronic fuel injection engine, the fuel consumption data is obtained by calculation. The data processing and drawing unit first uses the second formula to obtain the single fuel mass of a single injection of the electronic fuel injection engine; then, based on the single fuel mass, the third formula is used to calculate the fuel consumption per unit time of the electronic fuel injection engine.

[0023] Among them, the second formula is as follows: 2ρP0=[m÷(b×A×t)] 2 ; The third formula is as follows: M = m × N; Wherein, P0 is the rail pressure detected by the rail pressure sensor, t is the injection pulse width of the electronic fuel injection engine transmitted from the control unit of the electronic fuel injection engine to the data acquisition unit, N is the number of injections of the electronic fuel injection engine per unit time, b is the flow coefficient of the fuel injection nozzle of the electronic fuel injection engine, A is the cross-sectional area of ​​the fuel injection nozzle, ρ is the fuel density, m is the single fuel mass of a single injection of the electronic fuel injection engine, and M is the fuel consumption of the electronic fuel injection engine per unit time.

[0024] The power speed curve, torque speed curve and fuel consumption speed curve play many roles in the test of UAV carburetor engine. For example, the power speed curve can be used to evaluate the power performance of the carburetor engine and determine the effective working range of the carburetor engine. The torque speed curve can be used to evaluate the starting and acceleration performance of the carburetor engine and to perform load capacity analysis. The fuel consumption speed curve can be used to evaluate the fuel economy of the carburetor engine. By analyzing the fuel consumption speed curve, the working conditions of the carburetor engine can be optimized, such as adjusting the parameters of the carburetor to make the carburetor engine consume less fuel within the commonly used speed range.

[0025] The power speed curve, torque speed curve and fuel consumption speed curve also play many roles in the test of UAV electronic fuel injection engine. For example, the power speed curve can be used to accurately reflect the power output characteristics of the electronic fuel injection engine under various working conditions, and can also be used as a reference for the adjustment of the control unit of the electronic fuel injection engine. The torque speed curve can be used to analyze the power response characteristics of the electronic fuel injection engine and determine the efficient working range of the electronic fuel injection engine. The fuel consumption speed curve can be used to understand the fuel consumption law of the electronic fuel injection engine at different speeds, which helps to formulate energy-saving flight strategies for UAVs.

[0026] In summary, the present invention can be used for testing both carburetor engines of UAVs and electronic fuel injection engines of UAVs, thereby solving the problem that the electrical system of the existing UAV engine test bench cannot meet the testing requirements of both carburetor engines and electronic fuel injection engines.

[0027] In some exemplary embodiments, in order to avoid inaccurate test results of the engine to be tested due to inaccurate sensor measurements, Figure 2 As shown, the sensor module also includes a strain gauge torque sensor and a Hall effect speed sensor. The strain gauge torque sensor is installed on the output shaft of the engine to be tested to detect the torque of the engine to be tested; the Hall effect speed sensor is installed on the crankshaft of the engine to be tested to detect the speed of the engine to be tested. Assume that the torque detected by the torque speed sensor is T1, the torque detected by the strain gauge torque sensor is T2, the speed detected by the torque speed sensor is n1, and the speed detected by the Hall effect speed sensor is n2.

[0028] Before the data processing and drawing unit calculates the power of the engine to be tested and draws the speed curve, it first calibrates the torque and speed using the following calibration rules: When |T1-T2|÷T1×100%≤K1% and |T1-T2|÷T2×100%≤K1%, the torque verification is qualified.

[0029] When |n1-n2|÷n1×100%≤K2% and |n1-n2|÷n2×100%≤K2%, the speed calibration is qualified.

[0030] Wherein, T1 is the torque detected by the torque speed sensor, T2 is the torque detected by the strain gauge torque sensor, n1 is the speed detected by the torque speed sensor, n2 is the speed detected by the Hall effect speed sensor, K1 and K2 are the first verification threshold and the second verification threshold, 0.5≤K1≤2, 0.5≤K2≤2.

[0031] When the torque and speed are checked and qualified, the data processing and drawing unit draws the speed curve of the engine to be tested. Otherwise, the data processing and drawing unit sends an abnormal signal to the alarm to inform the staff of the abnormal detection data.

[0032] The present invention uses two sensors with different working principles to check the detection data. When the torque and speed are checked, the power of the engine to be tested is calculated and the speed curve is drawn, which effectively avoids the problem of inaccurate test results of the engine to be tested due to inaccurate sensor measurement. When the torque or speed check fails, the data processing and drawing unit sends an abnormal signal to the alarm to notify the staff that the detection data is wrong.

[0033] In some exemplary embodiments, Figure 2 As shown, the sensor module also includes a temperature sensor, which includes an intake temperature sensor for detecting the intake temperature of the engine to be tested, an exhaust temperature sensor for detecting the exhaust temperature of the engine to be tested, and a coolant temperature sensor for detecting the coolant temperature of the engine to be tested.

[0034] In the test of the engine to be tested, various temperature sensors play an important role. For example, the intake temperature sensor can monitor the intake temperature of the engine to be tested, which has a great influence on the combustion efficiency of the engine to be tested. The intake temperature sensor accurately measures the temperature of the air entering the engine to be tested, which can help engineers understand whether the intake temperature is in the appropriate range. Too high or too low intake temperature may lead to incomplete combustion, which in turn affects the power output and fuel economy of the engine to be tested. The exhaust temperature sensor is used to monitor the exhaust temperature of the engine to be tested. Exhaust temperature is a key indicator reflecting the combustion condition of the engine to be tested. By monitoring the exhaust temperature, it can be determined whether the fuel is fully burned. If the exhaust temperature rises abnormally, there may be a problem in the combustion process. The coolant temperature sensor can be used to monitor the coolant temperature.

[0035] The main control module is connected to a coolant circulation system, and the coolant circulation system is electrically connected to a data acquisition unit and a data processing and drawing unit. The coolant circulation system includes a compressor and an electric energy meter for detecting power consumption of the compressor.

[0036] The data acquisition unit and the data processing and drawing unit are both electrically connected to a coolant circulation system. The coolant circulation system includes a compressor and an electric energy meter for detecting the power consumption of the compressor. The data processing and drawing unit calculates the transferred heat during the test of the engine under test by a fourth formula. The fourth formula is as follows: Q = (W × η + c × m0 × ΔT) × b; Wherein, Q is the heat transferred during the test of the engine to be tested, W is the power consumption of the compressor detected by the electric energy meter during the test, η is the mechanical efficiency of the compressor, c is the specific heat capacity of the coolant, m0 is the total mass of the coolant in the coolant circulation system, η, c and m0 are measured in advance before the test and stored in the data acquisition unit; ΔT=T2-T1, is the temperature difference between the coolant temperature sensor and the data acquisition unit during the test, T1 is the temperature data transferred from the coolant temperature sensor to the data acquisition unit before the test starts, and T2 is the temperature data transferred from the coolant temperature sensor to the data acquisition unit in real time during the test; b is the ambient temperature adjustment coefficient; when |Q-Q0|÷Q×100%>K3%, the data processing and drawing unit sends an abnormal signal to the alarm to notify the staff to detect the engine thermal load condition. Among them, Q0 is the heat transfer threshold, K3 is the third verification threshold, 5≤K3≤10. In the embodiment of the present application, K3 cannot be too large, otherwise it will lead to the inability to accurately detect abnormal conditions. It also cannot be too small, otherwise it will easily lead to the phenomenon of misjudging normal situations as abnormal situations.

[0037] In an embodiment of the present application, the ambient temperature will affect the intake density, combustion efficiency and heat dissipation efficiency of the engine. For example, in a high temperature environment, the air density decreases and the intake volume decreases, which may lead to a decrease in engine performance. Therefore, when calculating the transfer heat Q of the engine to be tested during the test, it is necessary to take into account the change in ambient temperature and adjust the calculation results based on different ambient temperatures, so it is necessary to set the ambient temperature adjustment coefficient b. By constructing a three-dimensional physical model of the drone and setting the flow field area, the temperature field and flow field distribution of the flow field in the engine compartment of the three-dimensional physical model can be obtained, and then the ambient temperature and engine status can be monitored in real time to determine the ambient temperature adjustment coefficient b. It is also possible to establish a temperature-performance curve to calculate the ambient temperature adjustment coefficient b at different ambient temperatures. For example, if the engine power decreases by 5% for every 10°C increase in ambient temperature, the ambient temperature adjustment coefficient b can be set to a power adjustment of 5% for every 10°C change.

[0038] A series of verification experiments can also be conducted to test the engine under actual environmental conditions to verify the accuracy and effectiveness of the ambient temperature adjustment coefficient b. Based on the test results of the verification experiment, the ambient temperature adjustment coefficient b is corrected and fed back to ensure that it is applicable under different ambient temperatures, and the determined ambient temperature adjustment coefficient b is pre-input into the main control module.

[0039] For example, the ambient temperature adjustment coefficient b may be determined according to the following formula: ; Wherein, b represents the ambient temperature adjustment coefficient, T represents the current ambient temperature, P represents the performance parameter of the engine, ∆T represents the temperature change (i.e., the difference between the current ambient temperature and the reference ambient temperature), T0 represents the reference ambient temperature, and the reference ambient temperature here is an artificially set ambient temperature (e.g., 20°C). The reference performance parameters of the engine are obtained at the reference ambient temperature. This application uses the reference ambient temperature and the reference performance parameters of the engine as references to obtain other ambient temperatures and their corresponding engine performance parameters for comparative analysis, and then scientifically and reasonably determines the ambient temperature adjustment coefficient b during the test of the engine to be tested.

[0040] The main heat sources inside the drone include motors, ESCs (electronic speed regulators), controllers, sensors, communication modules, and batteries, etc. For the heat transfer threshold Q0, first, a series of laboratory experiments are conducted under the same test conditions as the actual test. The laboratory experiments use qualified engines (electronic fuel injection engines and carburetor engines). The calculated heat transfer during the test of qualified engines is the heat transfer threshold Q0, and the determined heat transfer threshold Q0 is pre-input into the main control module.

[0041] In addition, according to the relevant provisions of the engines, propellers, and parts installed on civil unmanned aircraft systems, type certificates, supplementary type certificates, parts manufacturer approvals, and technical standard project approvals are issued. These standards and regulations provide a basis for the value of the heat transfer threshold Q0. The heat transfer during UAV engine testing and the value of the heat transfer threshold Q0 involve heat transfer management, heat source identification, simulation methods, and relevant standards and regulations. Through the selection of reasonable heat sources, heat conduction paths, heat dissipation materials, etc., the heat generated by the UAV during operation can be effectively managed and eliminated. At the same time, through simulation tests and actual flight data, combined with relevant standards and regulations, the appropriate heat transfer threshold Q0 can be determined.

[0042] The data processing and drawing unit sends an abnormal signal to the alarm, notifying the staff to detect the engine thermal load condition, engine air intake condition, coolant circulation system working condition, etc.

[0043] In some exemplary embodiments, Figure 2 As shown, the sensor module also includes a pressure sensor installed on the engine intake pipe for detecting the intake pressure; the data acquisition unit receives the pressure data detected by the pressure sensor and transmits it to the data processing and drawing unit; the data processing and drawing unit draws a time intake pressure curve and a time speed curve according to the received pressure data and the speed of the engine to be tested.

[0044] During the test of the engine under test, both the time intake pressure curve and the time speed curve play an important role. The time intake pressure curve can reflect the intake process of the engine under test, and can help determine whether the intake is smooth and whether the intake volume is sufficient. For example, a sudden drop in intake pressure may mean that the intake duct is blocked or a component is damaged, affecting the intake efficiency. By monitoring the time intake pressure curve, we can also understand the response characteristics of the intake system to different working conditions, which helps to optimize the design and adjustment of the intake system.

[0045] The time-speed curve can reflect the change in the running speed of the engine under test. The starting performance, acceleration performance and idling stability of the engine under test can be seen from the time-speed curve. For example, the speed of speed increase can intuitively reflect the power response of the engine under test. In addition, combined with the time-intake pressure curve, the relationship between the two can be analyzed to study the influence of the intake volume on the speed of the engine under test, so that the engine under test can obtain the appropriate intake volume under different working conditions, ensuring the performance of the engine under test, fuel economy and reducing pollutant emissions.

[0046] The intake pressure threshold F0 and the time pressure threshold curve of the engine under test are input into the storage unit through the data input unit. The intake pressure threshold F0 refers to the maximum and minimum intake pressure values ​​set during the engine test to ensure the normal operation and stable performance of the engine. The intake pressure threshold F0 of the present application is measured by selecting qualified engines (electronic fuel injection engines and carburetor engines) in laboratory experiments under a series of test conditions, and the intake pressure threshold F0 is pre-input into the main control module.

[0047] The data processing and drawing unit compares the received intake pressure F with the intake pressure threshold F0 at the same time. When |F-F0|÷F×100%>K4%, it indicates that the intake pressure is distorted. When the causes other than the intake duct structure are eliminated, it helps engineers optimize the intake duct structure. In the formula |F-F0|÷F×100%>K4%, 5≤K4≤20. Specifically, K4 can be 5, 8, 9.5, 10, 13, 16, 18.5, 20, etc. K4 cannot be too large, otherwise the intake pressure distortion cannot be accurately detected. It cannot be too small, otherwise the normal intake pressure is easily judged as abnormal intake pressure distortion.

[0048] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. 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. An electrical system of a UAV carburetor-compatible electronic fuel injection engine test bench, comprising a power module, characterized in that: Also includes: Sensor modules, including torque and speed sensors, fuel consumption sensors, and rail pressure sensors; The torque and speed sensor is used to measure the torque and speed of the output shaft of the engine to be tested, the fuel consumption sensor is used to measure the fuel consumption of the carburetor engine, and the rail pressure sensor is used to measure the pressure in the fuel rail of the electronic fuel injection engine; A main control module, comprising a control unit, a data acquisition unit, and a data processing and drawing unit; the control unit is electrically connected to the engine to be tested, and is used to control the start and stop of the engine to be tested; the data acquisition unit is communicatively connected to the sensor module and the control unit of the engine to be tested, and is used to receive the detection data of the sensor module and the control data of the control unit, and transmit them to the data processing and drawing unit; wherein the data processing and drawing unit is used to calculate the power and fuel consumption of the engine to be tested according to the received detection data and control data, and draw a speed curve; wherein the speed curve includes a power speed curve, a torque speed curve, and a fuel consumption speed curve; The display module is connected to the main control module for displaying the speed curve drawn by the data processing and drawing unit.

2. The electrical system of the UAV carburetor compatible electronic fuel injection engine test bench according to claim 1, characterized in that: The power supply module includes an air switch and a switching power supply; the input end of the air switch is electrically connected to the external power supply, the output end of the air switch is electrically connected to the input end of the switching power supply, and the output end of the switching power supply is electrically connected to the sensor module and the main control module.

3. The electrical system of the UAV carburetor compatible electronic fuel injection engine test bench according to claim 1, characterized in that: Also includes a switching relay; The control unit is electrically connected to the engine to be tested via a switch relay; The switch relay includes a start relay and a flameout relay.

4. The electrical system of the UAV carburetor compatible electronic fuel injection engine test bench according to claim 1, characterized in that: The data processing and drawing unit calculates the power of the engine to be tested by a first formula; the first formula is as follows: P = T × n ÷ 9549; Wherein, P is the power of the engine to be tested, T is the torque detected by the torque speed sensor, and n is the speed detected by the torque speed sensor.

5. The electrical system of the UAV carburetor compatible electronic fuel injection engine test bench according to claim 1, characterized in that: The data processing and mapping unit is used to determine the fuel consumption per unit time of the electronic fuel injection engine, including: The second formula is used to obtain the single fuel mass of a single fuel injection of the electronic fuel injection engine; The fuel consumption per unit time of the electronic fuel injection engine is calculated using the third formula based on the single fuel mass; Among them, the second formula is as follows: 2ρP0=[m÷(b×A×t)] 2 ; The third formula is as follows: M = m × N; Wherein, P0 is the rail pressure detected by the rail pressure sensor, t is the injection pulse width of the electronic fuel injection engine transmitted from the control unit of the electronic fuel injection engine to the data acquisition unit, N is the number of injections of the electronic fuel injection engine per unit time, b is the flow coefficient of the fuel injection nozzle of the electronic fuel injection engine, A is the cross-sectional area of ​​the fuel injection nozzle, ρ is the fuel density, m is the single fuel mass of a single injection of the electronic fuel injection engine, and M is the fuel consumption of the electronic fuel injection engine per unit time.

6. The electrical system of the UAV carburetor compatible electronic fuel injection engine test bench according to claim 1, characterized in that: The sensor module also includes a strain gauge torque sensor and a Hall effect speed sensor; The strain gauge torque sensor is installed on the output shaft of the engine to be tested, and is used to detect the torque of the engine to be tested; The Hall effect speed sensor is mounted on the crankshaft of the engine to be tested and is used to detect the speed of the engine to be tested.

7. The electrical system of the UAV carburetor compatible electronic fuel injection engine test bench according to claim 6, characterized in that: The data processing and drawing unit is communicatively connected with an alarm; Before drawing the speed curve of the engine to be tested, the data processing and drawing unit first checks the torque and speed based on the checking rules; wherein the checking rules include: When |T1-T2|÷T1×100%≤K1% and |T1-T2|÷T2×100%≤K1%, the torque check is qualified; When |n1-n2|÷n1×100%≤K2% and |n1-n2|÷n2×100%≤K2%, the speed calibration is qualified; Wherein, T1 is the torque detected by the torque speed sensor, T2 is the torque detected by the strain gauge torque sensor, n1 is the speed detected by the torque speed sensor, n2 is the speed detected by the Hall effect speed sensor, K1 and K2 are the first verification threshold and the second verification threshold, 0.5≤K1≤2, 0.5≤K2≤2; When the torque and speed are calibrated to be qualified, the data processing and drawing unit draws the speed curve of the engine to be tested; otherwise, the data processing and drawing unit sends an abnormal signal to the alarm to inform the staff that the detection data is abnormal.

8. The electrical system of the UAV carburetor compatible electronic fuel injection engine test bench according to claim 1, characterized in that: The sensor module also includes a temperature sensor; The temperature sensors include an intake temperature sensor for detecting the intake temperature of the engine to be tested, an exhaust temperature sensor for detecting the exhaust temperature of the engine to be tested, and a coolant temperature sensor for detecting the coolant temperature of the engine to be tested.

9. The electrical system of the UAV carburetor compatible electronic fuel injection engine test bench according to claim 8, characterized in that: Also includes: The data acquisition unit and the data processing and drawing unit are electrically connected to the coolant circulation system; The coolant circulation system includes a compressor and an electric energy meter for detecting the power consumption of the compressor; The data processing and drawing unit calculates the transferred heat during the test of the engine under test by a fourth formula; the fourth formula is as follows: Q = (W × η + c × m0 × ΔT) × b; Wherein, Q is the transferred heat during the test of the engine to be tested, W is the power consumption of the compressor detected by the electric energy meter during the test, η is the mechanical efficiency of the compressor, c is the specific heat capacity of the coolant, m0 is the total mass of the coolant in the coolant circulation system, η, c and m0 are pre-measured before the test and stored in the data acquisition unit; ΔT=T2-T1, is the temperature difference transmitted from the coolant temperature sensor to the data acquisition unit during the test, T1 is the temperature data transmitted from the coolant temperature sensor to the data acquisition unit before the start of the test, and T2 is the temperature data transmitted from the coolant temperature sensor to the data acquisition unit in real time during the test; b is the ambient temperature adjustment coefficient; When |Q-Q0|÷Q×100%>K3%, the data processing and drawing unit sends an abnormal signal to the alarm to notify the staff to detect the engine thermal load condition; among them, Q0 is the heat transfer threshold, K3 is the third verification threshold, 5≤K3≤10.

10. The electrical system of the UAV carburetor compatible electronic fuel injection engine test bench according to claim 1, characterized in that: The sensor module also includes a pressure sensor mounted on the engine intake duct for detecting intake pressure; The data acquisition unit receives the pressure data detected by the pressure sensor and transmits it to the data processing and drawing unit; The data processing and drawing unit draws a time intake pressure curve and a time speed curve according to the received pressure data and the speed of the engine to be tested; The data processing and mapping unit compares the received pressure data with the intake pressure threshold at the same time. When |F-F0|÷F×100%>K4%, the data processing and mapping unit sends an abnormal signal to the alarm to notify the staff that the engine has intake pressure distortion; wherein F is the pressure data, F0 is the intake pressure threshold, K4 is the fourth verification threshold, and 5≤K4≤20.

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