CN113250954A - Micro-flow supply method of electric gear pump based on electromagnetic valve time domain opening control - Google Patents
Micro-flow supply method of electric gear pump based on electromagnetic valve time domain opening control Download PDFInfo
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- CN113250954A CN113250954A CN202110536991.5A CN202110536991A CN113250954A CN 113250954 A CN113250954 A CN 113250954A CN 202110536991 A CN202110536991 A CN 202110536991A CN 113250954 A CN113250954 A CN 113250954A
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- Prior art keywords
- flow
- gear pump
- electromagnetic switch
- supply
- switch valve
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C11/00—Combinations of two or more machines or pumps, each being of rotary-piston or oscillating-piston type; Pumping installations
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
- F02C7/00—Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
- F02C7/22—Fuel supply systems
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
- F02C7/00—Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
- F02C7/22—Fuel supply systems
- F02C7/232—Fuel valves; Draining valves or systems
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
- F02C9/00—Controlling gas-turbine plants; Controlling fuel supply in air- breathing jet-propulsion plants
- F02C9/26—Control of fuel supply
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C14/00—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations
- F04C14/08—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations characterised by varying the rotational speed
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C14/00—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations
- F04C14/24—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations characterised by using valves controlling pressure or flow rate, e.g. discharge valves or unloading valves
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P6/00—Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor
- H02P6/08—Arrangements for controlling the speed or torque of a single motor
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Rotary Pumps (AREA)
Abstract
The invention discloses a micro-flow supply method of an electric gear pump based on electromagnetic valve time domain opening control. Aiming at the problem that the flow supply of a gear pump driven by a brushless direct current motor without a sensor exceeds the actual requirement under the lowest controllable stable rotating speed, 2 high-speed electromagnetic switch valves with the same characteristics are connected in parallel at the outlet of the oil pump and are controlled by an electromagnetic valve controller, wherein one high-speed electromagnetic switch valve controls the supply flow with a certain time domain opening degree, the other high-speed electromagnetic switch valve controls the backflow with the opposite action, the frequency of the switching action is as fast as possible on the premise of ensuring that the switch valve can be reliably opened and closed, the stability of the supply flow is met, and the flow can be adjusted by controlling the time domain opening degree. The invention can overcome the difficulty of stable control of micro flow of the gear pump driven by the brushless direct current motor without a sensor, and simultaneously avoid the damage to the motor, the gear pump and a pipeline caused by high pressure at the outlet of the gear pump due to instantaneous shutoff of the valve when a single electromagnetic valve switch is adopted for supply.
Description
Technical Field
The invention belongs to the field of fluid control, and particularly relates to a tiny fuel flow oil supply system of an aircraft engine and a control method thereof.
Background
The novel micro turbojet engine generally adopts a starting mode of aviation kerosene direct ignition, an electric fuel pump is needed to provide small fuel quantity during ignition, the fuel quantity is about 25ml/min, and the fuel quantity far greater than the fuel quantity during ignition needs to be provided after ignition is successful. At present, the fuel supply of the fuel pump is reduced mainly by reducing the rotating speed of the electric fuel pump and adopting a proportional valve for throttling. The control difficulty of the brushless direct current motor is low rotating speed control, the non-inductive direct current brushless motor generally depends on back electromotive force detection to judge the phase change time, however, the back electromotive force is extremely low at low rotating speed and is difficult to detect, so that the low rotating speed is difficult to control and is difficult to stabilize. The proportional valve has the problems of untimely response, no dead zone for separation under extremely low flow, complex structure, high price and the like. How to realize the tiny fuel quantity oil supply of the electric fuel pump by a simple and economic method becomes the key for the successful ignition of the micro turbojet engine.
In order to solve the problem of how to reduce the oil supply amount of the fuel pump, chinese patent publication No. CN108488604A discloses an oil pump with adjustable flow rate, which adjusts the oil discharge amount of a gear pump by adjusting the meshing length between a driving gear and a driven gear through the cooperation of a hydraulic cylinder and a driving device of a spring. However, the oil pump disclosed in this patent has a problem that the mechanism is complicated and the cost is high, and the oil pump passively adjusts the meshing length between the drive gear and the driven gear in order to improve the operating efficiency of the oil pump and cannot actively control the amount of discharged oil.
In order to solve the problem of fuel flow regulation in an engine starting test, publication number CN109519285B discloses a fuel flow control system for an aircraft engine, which measures, regulates and controls the fuel flow according to the rate of increase of the engine speed in the engine starting stage. The control structure disclosed in this patent is not the same as the present patent and is difficult to adapt to the small flow control regulation requirements of a micro turbine engine.
In order to solve the problem of fuel temperature regulation in an engine starting test, publication No. CN112709638A discloses a fuel temperature regulation system and a fuel temperature regulation method for the engine high-low temperature starting test. Although the structure of the control system disclosed in the patent has certain similarities with that of the patent, the purpose of the control system is mainly to regulate the temperature of the fuel, and active control of the fuel flow and a control method of the electromagnetic valve on the time domain opening degree are not involved.
Disclosure of Invention
The invention provides a micro-flow supply method of an electric gear pump based on electromagnetic valve time domain opening control, which aims to solve the problem that the existing small gear pump is difficult to realize micro-flow supply and realize the micro-flow supply of the electric gear pump on the premise of ensuring simple structure and low cost.
The technical solution of the invention is as follows: the invention relates to a micro-flow supply method of an electric gear pump based on electromagnetic valve time domain opening control, which comprises the following control structures: the device comprises an electric gear pump, a brushless motor controller, a high-frequency electromagnetic switch valve and an electromagnetic valve controller. Wherein:
the brushless motor controller controls the rotating speed of the electric gear pump; a main pipeline is arranged on an outlet pipeline of the electric gear pump and connected with a supply electromagnetic switch valve to supply micro flow, a branch is arranged to be connected with a return electromagnetic switch valve and used for actively recycling residual flow after throttling, and an electromagnetic valve controller controls the opening and closing of the electromagnetic switch valve.
Further, the electric gear pump adopts a brushless direct current motor to drive the gear pump, and the brushless motor driver controls the rotating speed of the gear pump by controlling the rotating speed of the brushless direct current motor.
Further, the brushless motor driver should set the electric gear pump at a low rotation speed that can be accurately and stably controlled, and at this time, the outlet flow rate of the gear pump should be equal to or greater than the minute flow rate that needs to be supplied.
Furthermore, an outlet of the electric gear pump is connected with a supply electromagnetic valve on the main pipeline, the supply electromagnetic switch valve realizes a throttling effect in a time domain, and the outlet flow of the supply electromagnetic switch valve is the micro flow required to be provided.
Further, an outlet of the electric gear pump is connected with a backflow electromagnetic switch valve, and the backflow electromagnetic switch valve is opened and closed in a time domain and used for actively recovering residual flow.
Furthermore, the two electromagnetic switch valves have the same structure and characteristics, the excitation time is short, and the frequency of the switching action is as fast as possible on the premise of ensuring that the valves can be reliably opened and closed so as to meet the requirement of the stability of the supply flow.
Further, the working frequencies of the two electromagnetic switch valves are consistent, and the switching actions are opposite. At the moment that the main pipeline supply electromagnetic valve is opened, the branch return electromagnetic valve is closed to ensure the pressure and the stability of the supply flow; and at the moment that the main pipeline supply electromagnetic valve is closed, the branch return electromagnetic valve is opened, so that redundant flow can be released.
Has the advantages that: the invention discloses a micro-flow supply method of an electric gear pump based on electromagnetic valve time domain opening control, which can be applied to the starting oil supply process of a micro turbojet engine. Because the flow of the gear pump driven by the sensorless brushless direct current motor exceeds the actual flow demand at low rotating speed, the method can realize the accurate adjustment of micro flow and has small flow pulsation; meanwhile, abnormal high pressure at the outlet of the gear pump caused by instantaneous cut-off of the valve when output is supplied by adopting a single electromagnetic valve switch is avoided, and further the damage to the motor, the gear pump and the pipeline can be possibly caused. The invention has the advantages of simple structure and low cost.
Drawings
FIG. 1 is a diagram of a micro flow supply system for an electric gear pump based on time domain opening control of an electromagnetic valve;
FIG. 2 is a response diagram of a high-speed electromagnetic switch valve based on time-domain opening control according to an embodiment of the present invention;
FIG. 3 is a graph showing the relationship between the fuel flow and the rotational speed of the electric fuel pump and the time domain opening of the supply solenoid valve obtained in the experiment of the present example;
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples.
As shown in fig. 1, a schematic diagram of a gear pump micro flow supply method based on electromagnetic valve time domain opening degree control according to an embodiment of the present invention includes an electric gear pump 1, a brushless motor controller 2, a supply electromagnetic switch valve 3, a return electromagnetic switch valve 4, and an electromagnetic valve controller 5. The electric gear pump 1 is driven by a brushless direct current motor, and the brushless motor controller 2 controls the electric gear pump 1 to maintain a lower rotating speed which can be stably controlled. And fuel oil is sucked from an oil inlet of the electric gear pump 1, and an oil outlet of the electric gear pump 1 is connected with the supply electromagnetic switch valve 3 and the backflow electromagnetic switch valve 4.
The electromagnetic valve controller 5 controls the opening and closing of the electromagnetic opening/closing valve 3 and the return electromagnetic opening/closing valve 4 by electric signals. The excitation time of the supply electromagnetic switch valve 3 and the return electromagnetic switch valve 4 is as fast as possible on the premise of ensuring the normal opening and closing of the valves, and the faster the working frequency is, the smaller the fuel flow pulsation is.
When the brushless motor controller 2 works, the electric gear pump 1 is controlled to be in a lower rotating speed which can be stably controlled, fuel oil is sucked from an oil inlet of the electric gear pump 1 and then is discharged from an oil outlet of the electric gear pump 1 to input ports of the supply electromagnetic switch valve 3 and the backflow electromagnetic switch valve 4. The electromagnetic valve controller 5 adjusts the control signal to adjust the opening degree of the supply electromagnetic switch valve 3 and the return electromagnetic switch valve 4 in the time domain, thereby adjusting the output fuel flow rate of the supply electromagnetic switch valve 3 and realizing the micro flow fuel supply.
Fig. 2 is a response curve of the supply solenoid opening/closing valve 3 and the return solenoid opening/closing valve 4 based on time-domain opening control, and by controlling the opening of the solenoid opening/closing valves in the time domain, the adjustment of the supply flow rate from 0 to 100% can be achieved; meanwhile, when the supply electromagnetic switch valve 3 executes a transition process of opening the supply flow, the backflow electromagnetic switch valve 4 performs backflow in an opposite action, so that flow complementation and accurate control are realized. The frequency of the switching action is as fast as possible on the premise of ensuring that the switching valve can be reliably opened and closed so as to meet the requirement of stability of supply flow.
The sensorless brushless motor controller 2 selected in the embodiment of the invention adopts the FOC brushless motor driving technology of TI company, the maximum flow of the selected electric gear pump 1 is 2L/min, and the working frequency of the selected supply electromagnetic switch valve 3 and the selected throttling electromagnetic switch valve 4 is set to be 11 Hz. In the test, the rotation speeds of the electric gear pump 1 were set to 200rpm, 300rpm, 400rpm, and 500rpm, respectively. The opening degrees of the supply solenoid valve 3 in the time domain were set to 10%, 20%, 50%, and 100% at different rotational speeds, respectively, and the opening degrees of the corresponding return solenoid valve 4 in the time domain were set to 90%, 80%, 50%, and 0%, respectively, and the supply flow rates under these conditions were tested, respectively.
Fig. 3 is a graph plotted based on experimental data, and it can be seen that the opening degree of the supply solenoid valve 3 in the time domain is reduced, and the output of the minute flow rate can be realized at a high rotation speed of the electric gear pump 1. For example, when the rotation speed of the electric gear pump 1 is 500rpm, the opening degree of the supply electromagnetic switch valve 3 is 20%, and the corresponding opening degree of the return electromagnetic valve 4 is 80%, at this time, the fuel supply flow rate is about 18ml/min, and the supply requirement of small flow rate in the starting process of the micro turbojet engine is met.
The above description is only a preferred embodiment of the present invention, and is only used to illustrate the technical solution of the present invention, but not to limit the present invention, and it should be noted that: it will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the principles of the invention and these are intended to be within the scope of the invention.
Claims (3)
1. A micro flow supply method of an electric gear pump based on electromagnetic valve time domain opening control is characterized by comprising the following steps:
(1) the realization components comprise an electric gear pump 1, a sensorless brushless direct current motor controller 2, a supply electromagnetic switch valve 3, a backflow electromagnetic switch valve 4 and an electromagnetic valve controller 5;
(2) the sensorless brushless direct current motor controller 2 realizes the rotation speed control of the electric gear pump 1, and the flow of the electric gear pump 1 exceeds the actual required flow under the lowest controllable stable rotation speed;
(3) a main pipeline is arranged on an outlet pipeline of the electric gear pump 1 and connected with a supply electromagnetic switch valve 3 for supplying micro flow; a branch is arranged to be connected with a backflow electromagnetic switch valve 4 and used for actively recycling the surplus flow which is supplied to the electromagnetic switch valve 3 after throttling;
(4) the switching action frequency of the supply electromagnetic switch valve 3 and the backflow electromagnetic switch valve 4 is as fast as possible on the premise of ensuring that the valves can be opened in place and closed in place in each period;
(5) the two supply electromagnetic switch valves 3 and the return electromagnetic switch valve 4 with the same characteristics have the same working frequency and opposite switching actions, so that the supply of micro flow and the active recovery of redundant flow are realized.
2. The method for supplying the micro flow of the electric gear pump based on the time domain opening control of the electromagnetic valve as claimed in claim 1, wherein (4) the structure and performance of the supply electromagnetic switch valve 3 and the return electromagnetic switch valve 4 are completely consistent, the short excitation time is provided, and the control pipeline is opened and closed at a high speed to output on and off on the premise of ensuring the reliable opening and closing of the valves, so as to realize the effect of approximate continuous supply of the flow and the small flow pulsation.
3. The method for supplying the micro flow of the electric gear pump based on the time domain opening control of the electromagnetic valve according to claim 1, wherein (5) the two electromagnetic valve controllers realize the continuous regulation of the flow by outputting control signals with the same frequency and opposite switching actions, and the return electromagnetic switch valve of the branch is closed to realize the regulation and the supply of the flow while the main supply electromagnetic switch valve is opened; when the main pipeline supplies the electromagnetic switch valve to close, the branch return electromagnetic switch valve is opened to release redundant flow, and the switching actions of the two high-speed electromagnetic switch valves are complementary, so that abnormal high pressure at the outlet of the gear pump caused by instantaneous turn-off of the valve when a single electromagnetic switch is adopted for supply can be avoided, and further the damage to a motor, the gear pump and the pipeline possibly caused can be avoided.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110536991.5A CN113250954A (en) | 2021-05-17 | 2021-05-17 | Micro-flow supply method of electric gear pump based on electromagnetic valve time domain opening control |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110536991.5A CN113250954A (en) | 2021-05-17 | 2021-05-17 | Micro-flow supply method of electric gear pump based on electromagnetic valve time domain opening control |
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| CN113250954A true CN113250954A (en) | 2021-08-13 |
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| CN202110536991.5A Pending CN113250954A (en) | 2021-05-17 | 2021-05-17 | Micro-flow supply method of electric gear pump based on electromagnetic valve time domain opening control |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101169079A (en) * | 2006-10-26 | 2008-04-30 | 陶成 | Power machine fuel-economizing control device |
| CN102667061A (en) * | 2009-10-14 | 2012-09-12 | 克雷格·N·海山 | Internal combustion engine and supercharger |
| CN103557082A (en) * | 2013-10-25 | 2014-02-05 | 中国航空动力机械研究所 | Engine fuel supply device and control method thereof |
| CN204083744U (en) * | 2014-08-22 | 2015-01-07 | 珠海格力电器股份有限公司 | Oil supply unit of lubricating oil and centrifugal compressor |
| CN105443276A (en) * | 2014-09-02 | 2016-03-30 | 王淼 | Efficient mass transfer device of fuel engine |
| CN209637987U (en) * | 2019-02-15 | 2019-11-15 | 淮安淮液液压机械有限公司 | New structure compact gear pump |
| CN112304836A (en) * | 2019-08-02 | 2021-02-02 | 长江水利委员会长江科学院 | Portable small-flow constant-pressure test water supply device |
-
2021
- 2021-05-17 CN CN202110536991.5A patent/CN113250954A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101169079A (en) * | 2006-10-26 | 2008-04-30 | 陶成 | Power machine fuel-economizing control device |
| CN102667061A (en) * | 2009-10-14 | 2012-09-12 | 克雷格·N·海山 | Internal combustion engine and supercharger |
| CN103557082A (en) * | 2013-10-25 | 2014-02-05 | 中国航空动力机械研究所 | Engine fuel supply device and control method thereof |
| CN204083744U (en) * | 2014-08-22 | 2015-01-07 | 珠海格力电器股份有限公司 | Oil supply unit of lubricating oil and centrifugal compressor |
| CN105443276A (en) * | 2014-09-02 | 2016-03-30 | 王淼 | Efficient mass transfer device of fuel engine |
| CN209637987U (en) * | 2019-02-15 | 2019-11-15 | 淮安淮液液压机械有限公司 | New structure compact gear pump |
| CN112304836A (en) * | 2019-08-02 | 2021-02-02 | 长江水利委员会长江科学院 | Portable small-flow constant-pressure test water supply device |
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Application publication date: 20210813 |