WO2021224528A1

WO2021224528A1 - Traction control system for a two-wheel electric vehicle

Info

Publication number: WO2021224528A1
Application number: PCT/ES2021/070306
Authority: WO
Inventors: César ORTS ÁVILA; José ORTS ÁVILA
Original assignee: Cecotec Research And Development, S.L.
Priority date: 2020-05-04
Filing date: 2021-05-04
Publication date: 2021-11-11
Also published as: ES2875223A1

Abstract

Disclosed is a traction control system for a two-wheel electric vehicle, comprising a controller which takes readings of operating parameters of the motors, such as temperature and rotation speed, and of the rest of the components, such as the measurement of the intensity and the voltage of the battery, and regulates the torque that must be applied to each wheel to maintain optimal traction in response to the power demand of the user or driver of the vehicle.

Description

TRACTION CONTROL SYSTEM FOR TWO-WHEEL ELECTRIC VEHICLE

DESCRIPTION

TECHNICAL SECTOR

The present invention falls within the technical field of transport vehicles, more specifically transport vehicles with electrically powered traction means, and more specifically two-wheeled electric transport vehicles.

BACKGROUND OF THE INVENTION At present, people transport vehicles that use electrical energy to drive the means of movement are widely known, and more specifically, two-wheeled electric vehicles.

Additionally, in recent years, the use of this type of vehicle has expanded to a great extent, since the appearance of personal mobility vehicles, widely used in journeys that occur within urban centers, has multiplied exponentially. .

This type of personal mobility vehicle commonly has a traction wheel, in which an electric motor with a rotor and a stator is installed, which drives the vehicle during its movements. This motor is powered by batteries, and is driven by a controller, which is in charge of regulating the power that the battery delivers to the motor. In this way, the engine power is transformed into wheel movement thanks to the transmission, which can be belt, chain or direct.

Document ES2374232 belongs to the state of the art, which describes a slip control method, which acts on the traction torque of an electric motor that transmits the movement to a drive shaft associated with the wheels of the vehicle, performing the action in two phases, a first exponential reduction of the torque, during a reduction time; and a second of linear torque recovery. It also belongs to the state of the art e! Document EP0823348B1, which describes a controller that uses the speed of a rotor to control the output torsional force of an electric vehicle motor that monitors the rates of change of the signals, in such a way that the controller itself knows at all moment if the drive wheels are spinning. In this case, reduce the torsional force until traction is regained.

Document ES2336614 also belongs to the state of the art, in which a two-wheeled vehicle with integral electric traction is described comprising two electric drive motors, one on each wheel, with a selector by means of which the traction is set alternately in each wheel, which includes a torsion movement sensor that allows assisted pedaling to operate.

Finally, document WO2011067423 also belongs to the state of the art, in which a traction system for a direct drive electric vehicle is described, comprising a right electric motor with a first shaft, and a left electric motor with a second shaft. , and a traction control circuit with sensing means that transmits additional power to one of the wheels when it detects a loss of traction in the other.

As can be seen, electric vehicles that comprise wheel traction management systems belong to the state of the art, however, the systems do not apply to two-wheeled electric vehicles.

EXPLANATION OF THE INVENTION

The present invention aims to overcome the drawbacks of the state of the art detailed above, by means of a traction control system for a two-wheeled electric vehicle in the face of a power demand by the user, which allows individual control of each wheel. , optimizing the delivery of power from the battery to any of the two motors of an electric vehicle with two wheels, based on the measured parameters of the different components.

For this, the present invention proposes a power demand system, such as an accelerator, and a control system operatively connected to the control means. operation of the vehicle, which will take operating data from the device itself and will regulate the electric current from the battery to the drive motors, constantly adjusting the torque generated, so that traction losses are avoided.

The traction control system for two-wheelers comprises a front motor, installed on a front wheel, a rear motor installed on a rear wheel, at least one battery, at least one accelerator, braking means, and a control system. operatively connected to the above elements.

The system will also comprise different temperature sensors connected to the control system, to the electric motors and to the battery. It will also comprise current and voltage measuring means connected to the battery.

Finally, both motors, integrally connected to the wheels, will contain sensors for measuring the speed of rotation.

Following the previous reasoning, according to the user's power demand, the control system manages the torque delivered to each motor, using a specific algorithm, so that the torque demand is distributed between the two wheels, in such a way that so that none of the motors work in extreme conditions and preventing them from losing traction.

When engines are operating in extreme conditions, performance suffers, so the control system can redistribute power demand so that the prime mover returns to optimal operating conditions without affecting vehicle performance.

Additionally, the system can function as a traction control in case it detects that one of the wheels has lost traction, either due to environmental conditions or a high demand for acceleration. This is achieved by measuring the speed of rotation of the motors and, therefore, of the wheels.

The system could also be used in the event that it is capable of recognizing the inclination of the terrain on which it is circulating, which could be done thanks to a sensor. In this application, the vehicle control system would be able to apply a factor of correction for a higher demand for torque to the rear wheel which, in case of positive camber, would have better conditions for traction due to the distribution of weights.

In this way, a traction management system for a two-wheeled electric vehicle is achieved, which optimizes the operation of the motors installed in the wheels, obtaining an adequate response to any power demand by the driver; at the same time, it manages to avoid possible slipping due to loss of traction.

BRIEF DESCRIPTION OF THE DRAWINGS

To complement the description that is being made and in order to help a better understanding of the characteristics of the invention, a set of drawings is attached as an integral part of said description, in which, with an illustrative and non-limiting nature, the following has been represented. following:

Figure 1.- Diagram of the elements that make up the invention

Figure 2.- Algorithm for calculating the torque demand for each of the motors.

PREFERRED EMBODIMENT OF THE INVENTION

In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings that form a part of this specification, and in which specific preferred embodiments in which the invention may be carried out are shown by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to carry out the invention, and it is understood that other embodiments may be used and that structural, mechanical, electrical, and / or chemical logical changes may be made without departing from the scope of the invention. of the invention. To avoid details not necessary to enable those skilled in the art to carry out the detailed description, it should not, therefore, be taken in a limiting sense.

Specifically, the present invention proposes a traction control system of a two-wheeled electric vehicle that comprises at least: a front motor connected to a front wheel, a rear motor connected to a rear wheel, electrical supply means, power demand means, such as an accelerator, braking means, memory storage means, a power control module, and a control system operatively connected to the above means; where:

- the front rotor is integrally coupled to the front wheel;

- the rear rotor is integrally coupled to the rear wheel;

- the front engine comprises at least one temperature sensor and a rotational speed measurement sensor;

- the rear engine comprises at least one temperature sensor and a rotational speed measurement sensor;

- the supply means comprise a temperature sensor, electrical intensity measurement means, and voltage measurement means;

- the control system receives measurements from the previous sensors;

- the memory storage means comprise the limits for the values measured by the sensors; characterized in that when the power demand means are actuated, the control system uses the following operating algorithm:

- it first receives temperature data from the front engine (PM_T), the rear engine (SM_T), the power control module (PCM_T) and the power supply means (B_T), as well as the battery voltage (B_T) ;

- compares the measured data (PCM_T, PM_T, SM_T, B_T, B_V) with those stored in memory, to ensure that none of the limits established for each parameter are exceeded (PCM_MaxT, PM-MaxT, SMJVIaxT, B_MaxT, BJVIaxV) ;

- secondly, the control system receives the data of the rotational speed of the front engine (PM_Speed) and rear engine (SM_Speed);

- compares the speed data with each other, to ensure that both are rotating at the same or substantially the same speed, so as to ensure that neither of them is sliding;

- thirdly, and using the above measured parameters, in combination with the input value of the power demand means, calculate the necessary torque at the front engine (Determine PM_Torque) and / or rear engine (Determine SM_Torque);

- compares the calculated values with the limits established in memory to ensure that the maximum torque applicable to each motor (PM_MaxTorque, SM_MaxTorque) is not exceeded;

- finally, it applies the calculated torque values to the front engine (Output PM Jorque) and / or rear engine (Output SM_Torque)

According to this embodiment, the traction control system for two-wheeled electric vehicles would achieve a perfect distribution of the torque applied to each wheel, provided that the user actuates the power demand means.

In other words, when the vehicle's accelerator is actuated, the operating parameters of the front and rear motors, as well as the battery, would be checked, ensuring that none exceeded a limit value stored in memory.

In the event of an eventual exceeding of one of these limits, the control system would manage the operation of the vehicle to adjust the parameter within the established limits.

Once this check has been carried out, the control system would receive data on the speed of rotation of the front and rear motors, making a comparison of the two values, so that if they are not the same, it means that one of the wheels is turning at a lower speed and, consequently, that one of the wheels is skidding on the pavement, which makes it necessary to regulate the torque transmitted to the wheels through the motors.

Once the operating values have been read and it has been ensured that nothing exceeds the established limits, the control system calculates the torque required for each motor, so that the driver and / or user requirement of the vehicle can be optimally satisfied. vehicle.

These calculated values are again compared with the limits stored in the system memory, ensuring that none are outside the established range. and, if everything is correct, the torque values are applied to the motors.

In this way, a system of self-regulation of the torque applied to the wheels of the vehicle through the motors is achieved so that the operation is optimal according to the needs of the user.

In addition to controlling the complete system, measuring the operating parameters of all the components involved in the vehicle to ensure that none is operating outside the established limits that can lead to malfunctions or even deterioration and breakage of any of these components. .

In a preferred embodiment, the traction control system of a two-wheeled electric vehicle comprises a tilt measurement sensor, so that the control system uses a correction factor for the torque applied to the rear engine.

This modification of the torque balance applied between the two wheels is due to the fact that on sloping terrain where the vehicle must climb a steep slope, the rear engine is the one that has the greatest traction due to the weight distribution of the vehicle plus driver unit itself. .

It happens in the opposite way when you are facing an inclined terrain and you are descending a hill, with the front wheel being the one with the greatest traction thanks to the distribution of weights.

In a preferred embodiment, the speed measurement sensors will be Hall Effect sensors, since they are the most widely used in the field of measurement of rotational speeds of electric motors.

The industrial application of the present invention is clear, since it allows us to obtain a traction management system in a two-wheeled electric vehicle in such a way that an adequate torque is always guaranteed on each of the wheels, optimizing traction, and keeping the vehicle components operating within a safe range that prevents damage to them.

Claims

1. Traction control system of a two-wheeled electric vehicle comprising at least: - a front motor connected to a front wheel,

- a rear motor connected to a rear wheel,

- means of electrical supply,

- means of power demand,

- braking means, - memory storage means,

- a power control module,

- and a control system operatively connected to the above means where:

- the rotor of the front motor is integrally coupled to the front wheel; - the rear motor rotor is integrally coupled to the rear wheel;

- the rear engine comprises at least one temperature sensor and a rotational speed measurement sensor; - the supply means comprise a temperature sensor, electrical intensity measurement means, and voltage measurement means;

- the control system receives measurements from the previous sensors;

- the memory storage means include the limits for

- the values measured by the sensors; characterized in that when the power demand means are actuated, the control system uses the following operating algorithm:

- the control system receives temperature data from the power control module, from the front engine and from the rear engine, and temperature and voltage from the electrical supply means; - compares the received values with the limits stored in memory;

- the control system receives data on the rotational speed of the front engine and rear engine;

- compares the values received for the front motor's rotational speed and the rear motor's rotational speed; - using the above data, in combination with the input value of the power demand means, calculate the necessary torque on the front engine and the engine rear;

- compares the calculated values with the limits established in memory;

- applies the calculated torque values to! front engine and rear engine.

2. Traction control system of a two-wheeled electric vehicle according to the preceding claim, characterized in that it comprises a sensor for measuring inclination so that the control system uses a correction factor for the torque calculated and applied to the rear engine.

Traction control system of a two-wheeled electric vehicle according to any of the preceding claims, characterized in that the turning speed measurement sensors are Hall Effect sensors.