RU2495266C2 - Method to minimise fuel consumption of automotive ice with power accumulation system and device to this end - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: invention relates to automotive industry and can be used in vehicles incorporating electromechanical transmission wherein specific ICE fuel consumption is minimised owing to application of power accumulators. Proposed device comprises controlled fuel feed component incorporating ACS with feedback channels communicated with transmission elements and controlled electric power accumulator and flywheel-type power accumulator engaged with ICE shaft by controlled electromagnetic coupling. Control system control interaction of both accumulators in motion when traction motor consumes electric power and in braking when traction motor running in generator mode outputs power to drive system.

EFFECT: control system recovers power in turns at electric and flywheel power accumulators.

2 cl, 1 dwg

Description

The invention relates to the field of use of internal combustion engines (ICE) in cars and engine assemblies for various purposes, using energy storage devices, in particular with respect to vehicles (TS) for the transport of goods and passengers.

The energy efficiency of these devices is achieved through the use of ICE in the energy circuit - the mover of buffer energy storage devices that stabilize the operation of the ICE when changing the load conditions on the drive wheels during the movement of the vehicle.

Known methods [1, 2] to minimize the specific fuel consumption of the internal combustion engine of a vehicle with an electromechanical transmission, on which chemical current sources (batteries) or capacitor banks are used as a buffer energy storage.

The known method [3, 4] load balancing on the drive shaft of the internal combustion engine due to the inertial storage of mechanical energy (flywheel drive).

Both methods have their advantages and disadvantages.

The first method (electrical energy storage)

Disadvantages:

1) expensive electrochemical current sources or supercapacitors are required; the cost of a battery of drives increases in proportion to its capacity and can be more than half the cost of an electrified vehicle;

2) insufficient reliability of energy storage devices of this type and, accordingly, significant costs for repairing vehicles in the event of failure;

3) the structurally more complex issue of restarting the internal combustion engine in the short-term on-off modes is solved.

Benefits:

1) vehicle propulsion control is ideally implemented due to the presence of an electromechanical transmission equipped with a traction controlled electric motor;

2) eliminates the need for mechanical or hydromechanical devices that regulate the gear ratio of the transmission;

3) the process of energy recovery to the drive is reliably ensured both when the vehicle is braked and when it moves downhill;

4) provides the ability to control the value of the capacity of the energy storage [2].

The second method (flywheel drive)

Disadvantages:

1) the increased mass of the mechanical part of the drive, which at a given speed increases in proportion to the moment of inertia of the flywheel;

2) there remains a need for devices that regulate the gear ratio of the transmission;

3) it is very difficult to implement the process of energy recovery by transferring it back to the flywheel during braking of the vehicle (to transmit the power flow in the opposite direction, it is necessary to install a step-up gearbox that engages strictly at the initial moment of braking); in practice, energy can be returned to the flywheel only when the vehicle is moving downhill.

Benefits:

1) low cost of construction;

2) high reliability;

3) the issue of restarting the internal combustion engine in short-time off-on modes is ideally solved.

The proposed combined system has all the positive properties characteristic of each prototype individually, and accordingly, it is free from the disadvantages of the prototypes, which determines the novelty and effectiveness of this technical solution. Methods and devices that ensure the joint operation of drives of the first and second type are not found, therefore, provide the claimed technical solution for compliance with significant differences.

The aim of the invention is to increase the energy efficiency (COP) of the internal combustion engine when it is operated on vehicles under constantly changing load conditions.

The goal is achieved by the fact that the combined system implements all the positive qualities of existing energy storage:

1) the cost of electrochemical energy storage is reduced (about two times), since about half (or even more) of the stored energy is stored in the flywheel;

2) the electromechanical transmission with a traction controlled electric motor is saved, which eliminates the need for devices that regulate the gear ratio of the transmission;

4) the process of energy recovery to the drives is reliably ensured during the braking of the vehicle and when it moves downhill;

5) it is possible to control the value of the energy storage capacity;

6) the issue of restarting the internal combustion engine in short-time off-on modes is ideally solved.

Ultimately, due to these advantages, the cost of the structure is reduced, its energy efficiency and reliability are increased.

The latter property is especially useful in conditions of extreme operation of the vehicle, since it retains the ability to move for a certain time when one (or even two) of the most important components of the system fails: the internal combustion engine, the associated motor generator, any of two energy storage devices (one of energy storage devices in case of failure of the internal combustion engine should function).

Figure 1 shows a device for implementing this method.

The device includes: ICE 1, a controlled electromagnetic coupling 2, a flywheel drive (H-1) 3, an electric motor-generator (EMG-1) 4, a chemical (or capacitor) energy drive (H-2) 5, an electric motor generator (EMG-2) 6, mechanical transmission 7, propulsion device 8, mechanical brake device 9, control system (SU) 10, control mechanism of the fuel supplying working body (TPRO) 11.

The claimed method is implemented using the presented device.

The operation of the device is characterized by three states.

State 1 - system startup.

The driver sends a signal h1 to the engine control system (SU) to start the engine 1, as a result of which the electric power from the drive 5 is supplied to the electric motor-generator 4. The latter, working in the engine mode, spins the flywheel drive 3 to the specified (minimum necessary to start the engine) ω _{0 of} rotation, upon reaching which the control system gives a command to smoothly turn on the controlled electromechanical coupling 2 and the torque from the flywheel 3 is transmitted through the coupling 2 to the engine ICE shaft 1. At the same time, the control system sends a signal to turn on the TPR 10, resulting in ICE 1 is on. ICE begins to spin the flywheel 5 and the EMG-1 4 shaft, which is rigidly connected to the last one, which at that moment switches to electric power generation mode.

State 2 - system operation during vehicle movement.

The driver sends a h2 signal to the control system to control the EMG-2 6 traction electric motor, which, through transmission 7, reports the torque to the propulsion unit (wheel) 8 and the vehicle is driven. EMG-2 has the ability to receive power from both the N-2 drive (battery) and directly from EMG-1 (operating in generator mode), the joint operation of these sources of electricity to the EMG-2 traction electric motor is also allowed.

When the vehicle moves along the horizontal section of the track at low and medium speeds, the EMG-2 receives power only from the N-2 drive, the degree of “charge” of which is determined by the voltage at the terminals: U _max - maximum and U _min minimum voltage. As soon as the voltage at the terminals of the drive N-2 decreases to the value of U _min , SU generates a signal to turn on the excitation winding EMG-1, which begins to generate electricity for two consumers: EMG-2 and N-2.

If EMG-2 does not consume energy (the vehicle stands still or moves by inertia), then all the energy from EMG-2 is transferred to H-2, which takes charge to its full capacity, that is, until the voltage reaches U _max , after which EMG -1 stops working (excitation is turned off).

When EMG-2 is operating at high loads (when the vehicle moves at elevated speeds or to lift), the traction motor receives power from both N-2 and EMG-1.

In turn, EMG-1 receives mechanical energy from the output shaft of the flywheel drive N-1. The rotation frequency of the latter (and, accordingly, EMG-1) is controlled by a control system (CS) within the specified limits: ω _max - maximum, ω _min - minimum value. The maximum frequency can be set within the limits of the frequency of operation of the internal combustion engine (the most desirable value of the rotational speed at which the internal combustion engine has the highest torque and, therefore, the highest efficiency). The minimum frequency is determined by the stability of the internal combustion engine and should not be lower than ω ₀ . In this case, the characteristics of EMG-1 are also taken into account, namely its ability to generate electricity with specified parameters, which depends on the rotor speed.

At the initial moment, EMG-1 receives mechanical energy, which was stored by the flywheel drive N-1. As consumers consume this energy, the flywheel’s speed decreases to the threshold value ω _min . At this point, the SU sends a signal to turn on the electromagnetic clutch 2, TPRO 10 as a result of the internal combustion engine, untwisted to the frequency ω _min , is turned on and starts to accelerate the flywheel up to the specified maximum frequency value ω _max . After that, the coupling 2 and TPRO 10 are again turned off and the internal combustion engine stops.

A feature of the operation of the internal combustion engine in the system under consideration is that the TPRO always provides the maximum fuel supply, i.e. the internal combustion engine works only on the external speed characteristic, where the minimum specific fuel consumption is achieved. In addition, ω _max can be selected by the driver, taking into account the speed and load conditions of the vehicle. Obviously, the greater the power consumption of the EMG-2, which depends on the road conditions and the driving style of the driver, the more the value ω _{max is set} .

State 3 - operation of the system in the mode of recovery and braking.

When the driver starts the brake system (smoothly depressing the brake pedal) in order to brake and stop the vehicle (or to slow down the vehicle moving downhill), the h3 signal arrives in the control unit, the action of which ensures that the EMG-2 enters the generator mode. The electricity generated by the latter is transferred to the N-2 drive controlled by the principle of separation (association) of elements (see [2]). When recovery to the N-2 drive becomes impossible (the maximum voltage U _{max is} reached), the electricity generated by the EMG-2 is sent to the EMG-1, while the control system ensures the latter operates in the engine mode. EMG-1 begins to spin the flywheel, disconnected from the internal combustion engine, (recovering mechanical energy into it). This can be achieved only within the limits of the flywheel speed, not exceeding ω _max . After that, the excitation of EMG-1 and EMG-2 is turned off, and this ends the electrodynamic braking of the vehicle.

If the driver continues to hold the brake pedal, a signal h4 appears, which turns on the mechanical brake device 9, and the vehicle stops.

The use of this method and device increases the efficiency of the internal combustion engine, especially when the vehicle is moving in the mode of frequent acceleration and deceleration of the vehicle (vehicle traffic in the city). This is ensured primarily due to the fact that: 1) the internal combustion engine works only on the external speed characteristic; 2) in the presence of two energy storage devices and their joint operation, the volume of the regenerated braking energy of the vehicle increases; 3) reliable start of the internal combustion engine from the flywheel eliminates the idling of the internal combustion engine in the absence of load on it (which is not typical for prototypes).

Literature

1. Patent No. 2338081 of the Russian Federation, IPC F02D 17/04, F02D 41/30. Publ. in BI No. 31 10.11.2008

2. Patent No. 2418185 of the Russian Federation, IPC F02D 41/04, B60W 10/10. Publ. in BI No. 13 05/10/2011.

3. Gulia, N.V. Energy storage / N.V. Gulia. - M .: Nauka, 1980 .-- 152 p.

4. Patent No. 2033560 of the Russian Federation, IPC F03G 3/00, F16F 15/30. Publ. 04/20/1995.

Claims (3)

1. A method of minimizing fuel consumption due to automatic regulation of the operating mode of an internal combustion engine (ICE) connected to an electric energy generator that provides power to the vehicle’s electromechanical transmission, which is adjustable based on feedbacks from the propulsion electric motor of the propulsion device and electric energy storage device, characterized in the fact that in order to increase the efficiency of the internal combustion engine, an additional flywheel drive of mechanical energy is used, connected to the internal combustion engine by m controlled electromagnetic coupling, the internal combustion engine is started from a flywheel, driven by a generator operating in the engine mode and receiving energy from the electrochemical storage device when the internal combustion engine is powered, when both storage rings are saturated with energy, and the internal combustion engine speed reaches the maximum permissible value, control system (SU ) turns off the internal combustion engine, as the vehicle moves and energy is consumed by the traction motor, the speed of the flywheel drive decreases to the minimum acceptable value, then the control system provides on The operation of the internal combustion engine, which again “pumps up” the drive system, during the braking of the vehicle, the energy generated by the traction electric motor operating in the generator mode is provided, while the internal combustion engine is switched off by means of an electromagnetic clutch, and the generated energy first saturates the fully electrochemical storage, and then goes to the generator operating in engine mode, and untwists the flywheel to the set maximum value. 2. ICE fuel consumption minimizing device comprising a controlled TPRO (fuel supplying working body) equipped with an automatic control system with feedback with elements of an electromechanical transmission and a controlled electric energy storage device, characterized in that it further comprises a flywheel energy storage device connected to the internal combustion engine by means of a controlled electromagnetic clutch , a control system that determines the interaction of both drives as when driving a vehicle, when the traction motor reblyaet electricity, and when braking vehicle, when the drive motor operating in generator mode, gives energy to the drive system, wherein the CS provides the energy recovery alternately in each power storage unit. 3. The device according to claim 2, characterized in that during the initial start-up of an unheated ICE, the automatic control system is turned off, while the standard (installed by the manufacturer) TPR control system is used up to the internal combustion engine warming up to operating temperature.

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