Motor-detachable low-speed electromechanical auxiliary boost test bench

Abstract

The purpose of the present invention is to provide a motor-detachable low-speed electromechanical auxiliary supercharging test bench, including a combustion chamber, a compressor, a turbine, a DC brushless motor, and a new clutch. The compressor is connected to the DC brushless motor through a new clutch, and the DC brushless motor is connected to a motor controller. An EGR pipeline is installed between the intake pipeline and the exhaust pipeline, and a bypass pipeline is provided on the exhaust pipeline; the new clutch includes a housing, an outer ring, an inner ring, and a resistance ring. The outer ring, the inner ring, and the resistance ring are located in the housing. The inner ring is connected to the motor shaft of the DC brushless motor. The outer ring slides in the housing and is restricted by the upper part of the inner ring. The resistance ring is embedded in the outer end of the outer ring. The present invention adds a new clutch structure, which can quickly realize the separation and closing of the motor and the supercharger shaft, so as to achieve a better driving effect on the supercharger under low-load conditions and reduce the influence of the DC brushless motor that is separated under high-load conditions on the engine.

Description

Technical Field

[0001] The invention relates to an internal combustion engine supercharging test bench, in particular to a marine low-speed engine supercharging test bench. Background Art

[0002] Traditional exhaust gas turbocharged diesel engines use the exhaust heat of the internal combustion engine to drive the compressor through the turbine to increase the intake density of the diesel engine and make the combustion in the cylinder more complete. However, the process of accelerating the rotation of the compressor to convert the exhaust gas energy into the boost pressure takes a certain amount of time, and the "turbo lag" phenomenon is inevitable. In marine diesel engines, the turbocharger has a large moment of inertia, and this phenomenon is more obvious, resulting in insufficient intake, poor output torque, and deteriorated emissions under low-speed conditions. At the same time, under high-load conditions, problems such as accelerated wear and deterioration of the diesel engine caused by excessive boosting will occur, which greatly affects the energy efficiency of the ship. In order to improve the improvement effect of boosting on diesel engine performance, many studies have turned to turbocharging systems that improve the performance of marine exhaust gas turbocharged diesel engines. Currently, two-stage boosting, sequential boosting (STC), variable geometry turbine turbocharging (VGT) and electric assisted boosting technology (EAT) are widely studied.

[0003] There are various technical means for improving exhaust gas turbochargers. Two-stage turbocharging technology can increase the average effective pressure of diesel engines, improve the working performance of diesel engines under low loads, and expand the operating range of diesel engines by adjusting the pressure ratio distribution of high and low pressure stages through control valves. However, the inertia of the turbocharger impeller still exists, and the turbo hysteresis phenomenon has not been solved; the sequential turbocharging system is relatively complex, and it is difficult to avoid problems such as surging, large speed fluctuations, and black smoke during the switching process; variable geometry turbocharging technology controls the turbine blades according to the speed, has high supercharging efficiency and better solves the turbo hysteresis problem, but the structure is complex, and additional measurement and control of the blade angle are required. Strict requirements are placed on the turbine design to ensure aerodynamic efficiency and regulation performance under various working conditions; compared with various supercharging topologies, the electric-assisted turbocharging technology links the motor with the turbocharger, and the motor outputs power during the engine startup phase or low-load conditions, which can effectively increase the intake density, eliminate the turbo lag problem and speed up the system response speed, improve fuel economy, and enable ship engines to further develop towards electrification.

[0004] The brushless DC motor has the advantages of traditional DC motors, while eliminating the carbon brushes and slip ring structure, and can achieve low-speed, high-power operation. It is small in size and light in weight, so it has better stability and higher efficiency when used in ship auxiliary motors. It has excellent torque characteristics, good torque performance at medium and low speeds, large starting torque, can quickly drive the turbocharger to rotate, and has a small starting current. It is resistant to bumps and vibrations, runs smoothly and has a long service life. Summary of the invention

[0005] The object of the present invention is to provide a motor-detachable low-speed electromechanical auxiliary supercharging test bench capable of realizing rapid connection and disconnection between a DC brushless motor and a turbocharger rotor.

[0006] The object of the present invention is achieved in that:

[0007] The motor-detachable low-speed electromechanical auxiliary supercharging test bench of the present invention is characterized in that it includes a combustion chamber, a compressor, a turbine, a DC brushless motor, and a new clutch. The combustion chamber is connected to the compressor through an intake pipeline, the combustion chamber is connected to the turbine through an exhaust pipeline, the compressor and the turbine coaxially form a turbocharger, the compressor is connected to the DC brushless motor through a new clutch, the DC brushless motor is connected to a motor controller, an EGR pipeline is installed between the intake pipeline and the exhaust pipeline, an EGR valve is installed on the EGR pipeline, a bypass pipeline is extended on the exhaust pipeline, and an exhaust gas bypass valve is installed on the bypass pipeline; the new clutch includes a housing, an outer ring, an inner ring and a resistance ring, the outer ring, the inner ring and the resistance ring are located in the housing, the inner ring is connected to the motor shaft of the DC brushless motor, the outer ring slides in the housing, and is restricted by the upper part of the inner ring, the resistance ring is embedded in the outer end of the outer ring, and after the new clutch is engaged, the resistance ring transmits the power of the DC brushless motor to the shaft of the turbocharger.

[0008] The present invention may also include:

[0009] 1. When the speed of the brushless DC motor is lower than the speed of the turbocharger, under the action of the new clutch resistance ring, the new clutch outer ring rotates clockwise relative to the new clutch inner ring and moves away from the turbocharger shaft to achieve separation; when the brushless DC motor outputs torque to the turbocharger shaft, the speed of the brushless DC motor is higher than the speed of the turbocharger, the new clutch outer ring rotates counterclockwise relative to the new clutch inner ring and moves toward the turbocharger shaft, so that the new clutch outer ring engages with the turbocharger shaft end to achieve torque transmission.

[0010] 2. The motor controller includes a three-phase inverter module and a speed and temperature detection module, which convert the input DC power into AC power. When the ship is sailing at a low speed or in the starting stage, the motor controller receives the engine speed command and adjusts the SVPWM generation module in the motor controller according to the control strategy, that is, adjusts the position and speed of the DC brushless motor; the speed and temperature detection module detects the changes in the speed and temperature of the DC brushless motor in real time; and the compressor speed is increased by the DC brushless motor.

[0011] The advantages of the present invention are:

[0012] (1) The acceleration and speed control of the motor depend on the motor controller, which includes a monitoring module for the motor current, voltage, speed, temperature and other conditions, as well as a hardware protection module.

[0013] (2) The problem of poor acceleration performance of marine low-speed engines under low-load conditions or during the startup phase has been improved.

[0014] (3) Increasing the intake pressure effectively improves combustion in the combustion chamber.

[0015] (4) The selected brushless DC motor can achieve low-speed and high-power operation, is small in size and light in weight, and has better stability and higher efficiency when used in ship auxiliary motors.

[0016] (5) The new clutch has an external lubrication and cooling system to prevent overheating and require shutdown protection.

[0017] (6) Resistant to bumps and vibrations, smooth operation and long service life.

[0018] (7) The test bench can realize full-range automatic control over a long distance. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the present invention;

[0020] Figure 2 It is a structural schematic diagram of the novel clutch of the present invention. DETAILED DESCRIPTION

[0021] The present invention is described in more detail below with reference to the accompanying drawings:

[0022] Combination Figure 1-2 The present invention includes: an air filter 1, a brushless DC motor 2, a lubrication and cooling system 3, a new clutch 4, a compressor 5, an intercooler 6, an intake pipe 7, a combustion chamber 8, an exhaust pipe 9, an exhaust gas bypass valve 10, a turbine 11, a power battery 12, a motor controller 13, an EGR intercooler 14, and an EGR valve 15. Air enters the compressor 5 through the air filter 1 for air compression, and the controller controls the speed and voltage of the brushless DC motor 2 by receiving engine signals. The brushless DC motor 2 is engaged with the shaft end of the compressor 5 through the new clutch 4 to transmit torque, and the speed of the compressor 5 is rapidly increased. The exhaust gas enters the turbine 11 through the exhaust pipe 9. When the supercharger reaches the target speed, the new clutch 4 disconnects the motor 2 from the supercharger shaft system.

[0023] The test circuits of the test bench are all connected to the atmosphere. Figure 1 The arrow direction is the direction of gas flow, and the dotted line is the direction of signal and electrical energy flow.

[0024] The brushless DC motor 2 is placed on one side of the compressor 5, and the new clutch 4 designed is used to quickly connect and disconnect with the turbocharger shaft system. The motor controller 13 has a three-phase inverter module, which converts the input DC power into AC power, and belongs to the control main circuit part; the motor controller 13 also belongs to the control execution part. When the marine low-speed engine is at a low speed or the starting stage, the motor controller 13 will receive the corresponding acquisition signal, adjust and output SVPWM, control the brushless DC motor 2 to start, and drive the supercharger to accelerate through the new clutch 4. When engaged, the speed of the brushless DC motor 2 is greater than the speed of the supercharger, and the outer ring of the new clutch 4 rotates counterclockwise relative to the inner ring and moves toward the turbocharger shaft end at the same time, so that the resistance ring embedded in the outer shell of the new clutch 4 is connected with the turbocharger shaft end structure to achieve the function of transmitting torque. The motor controller 13 is equipped with a speed and temperature detection module, which can detect the changes in the speed and temperature of the motor 2 in real time; the compressor speed is increased by the brushless DC motor 2, the intake pressure is increased, and the problems such as insufficient power and black smoke caused by the deterioration of combustion in the engine combustion chamber are prevented.

[0025] The brushless DC motor 2 can achieve rapid separation and closing with the supercharger rotor through the novel clutch 4; the newly designed clutch 4 has a small mass and volume, and the entire switching process is short, thereby improving the rapid response of the electrically assisted turbocharger and the balance of the entire shaft system.

[0026] In order to realize the clutch of the brushless DC motor 2 and the turbocharger, the new clutch 4 is divided into an outer ring, an inner ring and a resistance ring. The motor shaft is rigidly connected to the inner ring of the clutch 4; the outer ring can slide within a certain range and is restricted by the components on the inner ring; the resistance ring is embedded in the end of the outer ring, and after engagement, the resistance ring can transmit the power output by the motor 2 to the turbocharger shaft; the turbocharger shaft end is designed for engagement with the resistance ring.

[0027] When the electrically assisted turbocharger is working, the order of torque transmission is motor shaft (new clutch inner ring) - new clutch outer ring - resistance ring - turbocharger shaft system; when working, when the engine is under low load or started, the motor controller 13 receives a signal, adjusts the voltage and speed of the DC brushless motor 2, the DC brushless motor 2 starts and drives the supercharger to accelerate, the speed of the motor 2 is greater than the speed of the turbocharger, the outer ring of the clutch 4 rotates counterclockwise relative to the inner ring and moves toward the designed shaft end structure of the compressor 5, so that the resistance ring embedded in the outer ring of the clutch 4 is engaged with the designed structure of the shaft end of the compressor 5, realizing the function of transmitting torque, driving the supercharger to accelerate rotation, the system responds quickly, can quickly increase the speed of the turbocharger, and effectively prevents the engine from insufficient air intake, poor output torque and deterioration of emissions under low working conditions.

[0028] When the speed of the brushless DC motor 2 is lower than the speed of the turbocharger, that is, the diesel engine is already under medium to high load conditions, the outer ring of the clutch 4 rotates clockwise relative to the inner ring under the action of the resistance circle, and moves away from the turbocharger shaft end, causing the outer ring resistance circle of the new clutch 4 and the shaft end to be disconnected, thereby achieving the purpose of disengagement. The DC brushless motor 2 is disconnected from the turbocharger shaft end design structure through the new clutch 4 at high speed of the entire supercharger, and the process is fast and reliable.

Claims

1. The motor-detachable low-speed electromechanical auxiliary boost test bench is characterized by: Including combustion chamber , compressor, turbine, DC brushless motor, new clutch, the combustion chamber is connected to the compressor through an intake pipe, the combustion chamber is connected to the turbine through an exhaust pipe, the compressor and the turbine are coaxial to form a turbocharger, the compressor is connected to the DC brushless motor through a new clutch, the DC brushless motor is connected to a motor controller, an EGR pipe is installed between the intake pipe and the exhaust pipe, an EGR valve is installed on the EGR pipe, a bypass pipe is extended on the exhaust pipe, and an exhaust gas bypass valve is installed on the bypass pipe; the new clutch includes a housing, an outer ring, an inner ring and a resistance ring, the outer ring, the inner ring and the resistance ring are located in the housing, the inner ring is connected to the motor shaft of the DC brushless motor, the outer ring slides in the housing, and is restricted by the upper part of the inner ring, the resistance ring is embedded in the outer end of the outer ring, after the new clutch is engaged, the resistance ring transfers the power of the DC brushless motor to the shaft of the turbocharger.

2. The motor-detachable low-speed electromechanical auxiliary boost test bench according to claim 1 is characterized in that: When the speed of the brushless DC motor is lower than the speed of the turbocharger, under the action of the new clutch resistance ring, the new clutch outer ring rotates clockwise relative to the new clutch inner ring and moves away from the turbocharger shaft to achieve separation; when the brushless DC motor outputs torque to the turbocharger shaft, the speed of the brushless DC motor is greater than the speed of the turbocharger, the new clutch outer ring rotates counterclockwise relative to the new clutch inner ring and moves toward the turbocharger shaft, so that the new clutch outer ring engages with the turbocharger shaft end to achieve torque transmission.

3. The motor-detachable low-speed electromechanical auxiliary boost test bench according to claim 1 is characterized by: The motor controller includes a three-phase inverter module and a speed and temperature detection module, which convert the input DC power into AC power. When the ship is sailing at a low speed or in the startup phase, the motor controller receives the engine speed command and adjusts the SVPWM generation module in the motor controller according to the control strategy, that is, adjusts the position and speed of the DC brushless motor; the speed and temperature detection module detects the changes in the speed and temperature of the DC brushless motor in real time; and the compressor speed is increased by the DC brushless motor.

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