Device for controlling at least one electric motor of a vehicle

Abstract

The invention relates to a device for controlling an electric motor (7) of a vehicle (1), comprising: a pedal assembly (14); means (23) for estimating state variables (Xi) each making it possible to estimate the value of one force from a set of forces (Fload) opposing or contributing to the progress of the vehicle (1); wherein the control means (25) comprise a memory storing a set of steady states (SSmap) of the pedal assembly (14) defining the instantaneous power (Pssp user) for keeping the speed (v) of the vehicle (1) constant according to the values of the state variables (Xi); the control means (25) being configured to accelerate or decelerate the vehicle (1) if the power applied by the user (Puser) is higher or lower, respectively, than the instantaneous power for keeping the speed of the vehicle constant (Pssp user).

Description

DEVICE FOR CONTROLLING AT LEAST ONE ELECTRIC MOTOR OF A VEHICLE DOMAINE TECHNIQUEThe present invention relates to a vehicle comprising a pedal assembly used to control the movement of the vehicle at least in part by means of an electric motor. Thus, the invention can be applied to electrically assisted vehicles and vehicles with exclusively electric propulsion. Preferably, the invention relates to a series hybrid vehicle comprising a pedal assembly, that is to say a pedal vehicle without mechanical transmission between the pedal assembly and the drive wheel(s), providing traction or propulsion by means of an electric motor. These vehicles are called “series hybrid” in certain classifications to show that the vehicles comprise two electric motors mounted in “series”: a motor operating mainly as a generator at the pedal assembly and a motor associated with the drive wheel.The term “hybrid” reveals that the energy used to move the vehicles comes from both the mechanical energy applied to the pedal assembly and the electrical energy contained in a battery. Thus, the invention relates to the technical field of land transport and can be implemented for leisure, sports or utility vehicles, for example for delivery vehicles. PRIOR ART Pedal vehicles are currently experiencing significant growth with the development of electrical assistance solutions. Electrically assisted vehicles are generally composed of a pedal assembly, a drive wheel providing traction or propulsion of the vehicle, a mechanical transmission connecting the pedal assembly to the drive wheel, an electric motor and a battery powering the electric motor.Thus, within the meaning of the invention, an electrically assisted vehicle always incorporates a mechanical transmission connecting the pedal assembly to the drive wheel, for example a chain or a belt. Electrical assistance can be used to limit the efforts required to rotate the drive wheel or the pedal assembly. With electrical assistance, it is possible to obtain cycles or velomobiles of low weight and volume that can weigh less than 50 kg, typically between 30 and 50 kg. For these vehicles, the power of the electrical assistance amounts to a few hundred Watts, typically 200 to 300 W. Their speed is relatively low, less than or close to 25 km / h. These vehicles are designed to use tracks and paths reserved for cycles. There are also series hybrid vehicles, often produced in the form of velomobiles.These vehicles do not incorporate a mechanical transmission connecting the pedal assembly to the drive wheel and at least one electric motor provides traction. The pedal assembly is used as a generator to recharge a battery supplying the electric motor. In addition, the pedal assembly is also used to control the vehicle's speed. These series hybrid vehicles have significant weights and volumes and generally weigh several hundred kilograms. The propulsion of these vehicles is therefore done exclusively by electric energy, their pedal assembly being then only present for the control of acceleration and possibly for the recharging of a battery supplying the electric motor of the velomobile. Electric propulsion is done by means of one or more motors with a total power of several kilowatts. Their speed is relatively high, most models being designed to travel at 80-120 km / h.These velomobiles travel on motorways, like a conventional car. Document EP3154815 describes such a vehicle, for example. The lightness of these velomobiles allows them, with the same battery carrying weight, to have a greater autonomy compared to an electric car. Speed control can be carried out by the driver using the pedals. The instruction applied to the propulsion motor is, for example, a function of the rotation rate of the pedals, and is determined so that the motor accelerates the rotation of the wheel by the engine torque that it generates. The power applied by the motor to the wheels can reach several thousand watts, and up to 10 or 12 kilowatts in particular, to allow circulation on the roadway normally reserved for cars. The pedal user can only reach a power of a few hundred watts, and an average user will have difficulty maintaining a power greater than 250 watts over time.A simple proportionality between the two powers, of the engine and the pedals, does not allow comfortable and precise driving. At low powers, speed control is not precise, and at high speeds the significant power developed cannot be maintained by the user. In addition, the natural variations in the power developed by the user on the pedals lead to significant power variations at the engine level and therefore a non-uniform speed which is detrimental to the comfort and perceived quality of the vehicle. Document EP3978345 discloses a variable proportionality control device and method, the proportionality coefficient varying with the selection of a gear ratio from a selection, thus emulating a cycle with different chainrings and sprockets for example. The user must however manually select the ratio, and the change is discrete and is accompanied by a power discontinuity.This same problem can be posed for an electrically assisted vehicle which uses a very high electric assistance ratio, typically greater than. 50%.There is therefore a need for a method for controlling the propulsion of an electric vehicle, with electrical assistance or series hybrid, by means of a pedal assembly making it possible: to precisely control the power of the motor, to reduce power variations at the motor level, and to maintain a high speed over a significant period without excessive effort from the user. STATEMENT OF THE INVENTION In order to meet this need, the invention proposes a device for controlling at least one electric motor of an electric vehicle with electric propulsion or traction controlled by a pedal assembly. More specifically, the invention proposes implementing an acceleration power control with a comparison between the power applied by the user and an expected power, obtained from a set of stationary pedal assembly speeds defining the instantaneous power applied by the user to the pedal assembly necessary to maintain the speed of the vehicle.To this end, the vehicle comprises:- at least one pedal assembly associated with means for estimating the instantaneous power applied by the user to the pedal assembly;- means for estimating state variables, typically but not necessarily or exclusively speed and slope, each making it possible to estimate the value of a force of a set of forces opposing or contributing to the forward movement of the vehicle, and- means for controlling the power applied to the at least one electric motor.The vehicle according to the invention is characterized in that said control means comprise an electronic memory in which is stored a set of stationary speeds of the pedal assembly defining the instantaneous power applied by the user to the pedal assembly necessary to maintain the speed of the vehicle constant as a function of the values of the state variables.The control means are then configured to: estimate the state variables and deduce therefrom the instantaneous power to be applied by the user to the pedals to maintain the speed of the vehicle, accelerate the vehicle if the instantaneous power applied by the user to the pedals is greater than the instantaneous power required to maintain the speed of the vehicle constant at the pedals; and decelerate the vehicle if the instantaneous power applied by the user to the pedals is less than the instantaneous power required to maintain the speed of the vehicle constant at the pedals. The motor controlled by means of the control module as described can then be controlled in acceleration by means of the pedals over a wide range of vehicle speeds, and therefore of motor powers, without exceeding the pedaling capabilities of the user.The invention therefore proposes to improve the control of the electric motor by a pedal assembly of a vehicle with electric assistance or series hybrid. The control device may also have one or more of the following characteristics. The set of stationary regimes may be such that for the sets of state variables for which the power to be applied by the user to the pedal assembly to maintain the speed of the vehicle is zero, the power required by the motor to maintain the speed of the vehicle is also zero. This equality makes it possible to model the natural behavior of a cycle in freewheel mode without direct haptic feedback between the electric motor and the pedal assembly. The acceleration or deceleration of the vehicle may be done simply by imposing a respectively positive or negative acceleration power setpoint.The device may further comprise means for estimating a load power corresponding to the power exerted by a set of forces opposing or contributing to the forward movement of the vehicle, and when the measured load power is estimated to be positive and the instantaneous power applied by the user is greater than the instantaneous power necessary to maintain the speed of the vehicle, the acceleration power setpoint is the product of an acceleration coefficient and the difference between the power applied by the user and the power to be applied by the user to the pedals to maintain the speed of the vehicle constant. This operation allows power steering without gear changes and with a continuous effort that feels natural.When the measured power of the set of forces opposing or contributing to the vehicle's forward motion is estimated to be positive, the instantaneous power required to maintain the vehicle's speed constant is positive, and the instantaneous power applied by the user to the pedals is strictly less than the instantaneous power required to maintain the vehicle's speed v, the acceleration power setpoint is equal to the product of the measured power of the set of forces opposing or contributing to the vehicle's forward motion multiplied by the difference between the instantaneous power applied by the user and the instantaneous power required to maintain the vehicle's speed constant, divided by the instantaneous power required to maintain the vehicle's speed constant. When decelerating by reducing pedaling power, the user then feels the forces opposing the vehicle's forward motion at the pedals.When the measured charging power and / or the instantaneous power required to maintain the vehicle speed constant is negative, the acceleration power setpoint is equal to the difference between, on the one hand, the product of the acceleration coefficient and the power developed by the user and the charging power. mesurée.The user then feels the driving effect of the forces. The three formulas applied under the conditions given in the preceding paragraphs, when used in combination, form a continuous effort control during progression with variation of the state variables, and give a natural and pleasant feeling at the pedal level for the user. The acceleration coefficient can in particular be equal to the quotient between on the one hand the difference between a maximum power of the vehicle engine and the instantaneous power of the engine necessary to maintain a constant speed of the vehicle, and on the other hand the difference between a maximum power developed by the user and the instantaneous power necessary to maintain a constant speed of the vehicle. The accessible range of engine powers is then indexed on the range of powers developable by the user.The state variables may further comprise at least one parameter from among the slope and the speed of the vehicle. With these two state variables alone, satisfactory behavior is obtained, allowing pleasant driving with realistic pedaling sensations. The state variables may, furthermore, comprise at least one parameter from among: the total weight of the vehicle, the type of road on which the vehicle is moving, the speed of the belly relative to the vehicle, etc. The behavior of the vehicle can then be modeled and rendered with greater precision. The invention also relates to the velomobile type vehicle, comprising a control device as described and at least one electric motor controlled by said control device.BRIEF DESCRIPTION OF THE FIGURESThe invention will be clearly understood upon reading the following description, the details of which are given solely by way of example, and developed in relation to the appended figures, in which identical references refer to identical elements:- Figure 1 is a side view of a vehicle according to a particular embodiment of the invention;- Figure 2 is a sectional view of the vehicle of Figure 1,- Figure 3 is a flowchart representation of the main components of the vehicle control device of the preceding figures,- Figure 4 is a graph of isometric lines of powers to be supplied to the engine to maintain a stationary regime as a function of the slope and the speed of the vehicle,- Figure 5 is a graph of isometric lines of powers to be supplied by the user to maintain a stationary regime as a function of the slope and the speed of the vehicle constructed from the graph of Figure 4.The embodiments of the figures are given for illustrative and non-limiting purposes, other embodiments are easily deducible from those represented by combination and variations. Other advantages and characteristics of the invention, as well as different embodiments are in the detailed description below. DETAILED DESCRIPTION OF THE INVENTION Figure 1 is a side view of a vehicle 1 of the velomobile type according to the invention. The vehicle 1 comprises a passenger compartment 10, comprising a bodywork closing the passenger compartment 10. The passenger compartment 10 has a general shape similar to that of a single-seater car, with side doors 11 and windows 12 comprising a windshield at the front of the vehicle 1. The windows 12 and the windshield are cut out of panels carrying them, and possibly closed with glass.The driver benefits, through these windows 12 and through the windshield, from a field of vision depending in particular on the external contour of the windows 12 and the windshield, as well as on the relative position of his head with respect to the windows or the windshield. The vehicle 1 has three wheels 31, 33, preferably with a rear driven wheel 31 and two front steered wheels 33 (only one of the two front wheels 33 is visible). Other embodiments may use two or four wheels. In addition, one or two front wheels may be driven in addition to or as an alternative to the drive of one or more rear wheels. Figure 2 is a sectional view of the vehicle of Figure 1. Figure 2 shows in particular the interior of the passenger compartment 10. The rear wheel 31 is connected to a drive device 5 such as a belt, a chain or a gear.The drive device 5 is in turn connected to an electric motor 7 which sets the rear wheel 31 in motion, using electrical energy stored in batteries 9, here located in a floor of the passenger compartment 10. The electric motor 7, and therefore the setting in motion of the wheels 31, 33, is controlled by means of a pedal assembly 14. A control unit (not shown) controls the electric motor 7, for example by increasing its speed and therefore the speed of the wheels 31, 33 and of the vehicle 1 in an increasing manner with the pedaling power at the pedal assembly. 14.According to a variant, in the absence of an electric motor 7 or in addition to it, part of the mechanical energy applied to the pedal assembly 14 is directly transmitted to the wheels 31, 33. The electric motor 7 can then be a simple electric assistance, exerting an assistance torque to that which the driver exerts directly by means of the pedal assembly 14. The pedal assembly 14 can in addition or as an alternative comprise a generator or an operation in generator mode, in which the torque applied by the driver is transmitted to the battery 9 to be restored later in the form of acceleration of the wheels 31, 33. An operation in generator mode is encountered in the pedal assembly 14 or induction motors. In this mode of operation, the pedal assembly 14 is connected to the battery 9, and provides a resistive torque. By overcoming this resistive torque, the driver induces an electric current charging the battery 9.The pedal assembly 14 is located at the front of the passenger compartment 10, in front of a seat, and above a seat base. The pedal assembly 14 is located at a distance of between 60 and 100 cm from the seat, corresponding to the expected length of the driver's legs. The seat rests on a rail or on an equivalent translational guide means. The rail in turn rests on a seat base which is integral with the floor of the passenger compartment 10 of the vehicle 1. The seat base is substantially flat, and oriented towards the axis of the pedal assembly 14. By thus orienting the plane of the seat base, the latter does not interfere during pedaling, in that it does not form a stop. In addition, the pedaling angle, that is to say the inclination of the axis going from the hip joint to the axis of rotation of the pedal assembly 14, remains constant regardless of the longitudinal position of the seat.A handlebar is positioned between the seat, with a U-shape, the bottom of which is located below the expected position of the driver's legs and comprising side handles located above the driver's legs or at the height thereof. The handlebar allows the wheels 31, 33 to be turned, at least at the front, in order to turn when driving. The handlebar is in particular integral in translation and movable in rotation relative to a pivot, which is itself integral with the seat or with means for positioning the handlebar. dédiés.The handlebar can in particular be pivoted in the transverse plane by action on the handles with a rotation comprised between two extreme steering angles of the order of plus or minus 20 to 30° relative to a rest position in which the rear wheel 31 is straight. According to a variant, the rear wheel 31 can be inclined by actuation of the handlebar, and the front wheels 33 are set in motion by the electric motor 7. The electric motor 7 is controlled by the driver by means of a control device 100, the main components of which are represented in the form of a flowchart in Figure 3. In Figure 3, the pedal assembly 14 receives an instantaneous power Puser from the driver, and the control means exert an acceleration a by applying a motor reference power Ptot sp to the electric motor 7 to modify the speed v of the vehicle 1.The speed v can in particular be deduced from the rotation speed of the wheels 31, 33, measured for example by means of angular position sensors of said wheels 31, 33. The instantaneous power Puser developed by the user is estimated by appropriate power estimation means located at the level of the crankset 14, for example a means of estimating the resistive torque exerted by the crankset 14 cooperating with means 21 of measuring the pedaling cadence applied by the user to the crankset. 14.The control device 100 comprises means 23 for estimating or measuring the value of state variables Xi making it possible to trace back to the value of each of the forces of a set of forces Fload opposing or contributing to the advance of the vehicle 1. Said estimation means 23 may in particular comprise means for estimating the state variable Xi, which is the speed v of the vehicle, to trace back to the drag in the air or even an anemometer, for the direct measurement of the speed of the air flow at the level of the vehicle, and making it possible to take into account the wind in addition to the speed v of the vehicle 1, and means for estimating the slope Slo on which the vehicle 1 is moving, to trace back to the force exerted by gravity, measured for example by means of accelerometers. The applicant has in particular noted that these two state variables Xi (slope Slo and speed v) alone make it possible to obtain a natural driving sensation, but other state variables X imeasured by means of the corresponding sensors can also be taken into account: weight of the vehicle 1, type of road surface, tire pressure of the wheels 31, 33, atmospheric pressure, type of wheels 31, 33 etc. The total power Ptot delivered by engine 7 is the sum of the power Pacc used to accelerate vehicle 1 and the load power Pload exerted by the set of forces Fload which must be supplied to maintain the constant speed:^ ^ ^^ ^^ ^^ = ^^ ^^ ^^ ^^ + ^^^^ ^^ ^^ ^^The device also includes a means for estimating the actual or measured load power Pload(t) corresponding to the power exerted by the set of forces Fload. For example, the actual load power Pload(t) can be deduced from the total power Ptot exerted by the engine 7, from which is subtracted the acceleration power Paccconverted into kinetic energy, product of the mass of the vehicle m, the speed v and the acceleration a: A positive power is considered driving while a negative power results in braking and then acceleration by moving the vehicle 1 backwards. The acceleration power Pacc corresponds to a variation in the total power of the motor7 transmitted to the wheel 31, 33. A control unit UC is connected to the estimation means 21, 23, as well as to a power variator Var, which controls the power Ptot delivered by the electric motor7 via the current i from the battery 9. The control unit UC and the variator Var form means for controlling the electrical power 25 supplied to the electric motor 7, i.e. the total power Ptot, and therefore the acceleration a.The control unit UC comprises in particular an electronic memory in which is stored a set of stationary regimes SSmap of the pedal assembly 14 defining, for each set of values of the state variables Xi from the sensors 23, an instantaneous power applied by the user Pssp user on the pedal assembly 14, defined as the power Pssp user necessary to maintain constant the speed v of the vehicle 1. Figure 4 is an example of the graph of the power value necessary for the motor 7 to maintain constant the speed of the vehicle Pssp mot which corresponds to the theoretical load power Pload(Xi) as a function of only the forces corresponding to the state variables Xi retained representative of the set of forces Fload: the slope Slo and the speed v. The power necessary for the motor 7 to maintain constant the speed of the vehicle Pload(Xi) is in particular calculable and calculated from the estimated values of the measured state variables Xi.The Applicant has notably noted that the choice of only the slope Slo and speed v, corresponding to the loads of gravity and drag in the air, makes it possible to obtain a pleasant and realistic behavior of the vehicle 1. Figure 4 shows isometric lines of the value of said power Pload(Xi) necessary to maintain constant the speed v of the vehicle 1 in the plane indexed by the speed v on the abscissa and the slope Slo on the ordinate. Several lines are represented, corresponding to different power values P1, P2, P3, P4. Along one of these isometric lines, the power necessary for the engine 7 to maintain constant the speed of the vehicle Pload(Xi) is equal to the value noted on the line: P1, P2, P=0, P3, P4. The power necessary for the engine 7 to maintain the speed Pload(Xi) is notably increasing with the slope Slo and the speed v.The isometric lines closest to the upper right corner therefore correspond to the high powers, the lines closest to the lower left corner correspond to the low powers. We therefore have P1 > P2 > 0 > P3 >. P4.One of the lines is the freewheeling line FW (Pacc = 0). It starts, at zero speed, at a slope value Slo slightly lower than 0 (line Slo = 0 shown in dotted lines), and descends towards negative slope values Slo as the speed v increases. This freewheeling line FW corresponds to the states where the vehicle 1 maintains its speed v constant in the absence of power supplied by the motor 7 (Pload(Xi) = 0). The freewheel FW starts, for a speed v of zero, at a slope Slo slightly negative and sufficient to overcome the resistive torques linked to mechanical friction. The freewheeling line FW descends as the speed v increases, due to the drag in the air which increases with said speed v and must be compensated.This power mapping is associated with a mapping of the pedaling power Pssp user to be applied to the crankset 14 to maintain the speed v of vehicle 1 constant as a function of the same state variables Xi, here the slope Slo and the speed v of vehicle 1. Several lines are represented, corresponding to different power values PU1, PU2, PU3, PU4. Along one of these isometric lines, the power required by the crankset 14 to maintain the power Pssp user is equal to the value noted on the line: PU1, PU2, P=0 PU3, PU4. The power required by the crankset 14 to maintain the speed of the vehicle Pssp user constant is notably increasing with the slope Slo and the speed v as in the case of the power of engine 7. The isometric lines closest to the upper right corner therefore correspond to high powers, the lines closest to the lower left corner correspond to low powers. So we have: PU1 > PU2 > 0 > PU3 > PU4.Negative power corresponds to braking power, braking triggered for example by backpedaling or by actuation of a dedicated brake control, the braking power being proportional to the level of actuation of the control. de frein.According to a specific embodiment, braking is done by actuation in the opposite direction of the pedals of the crankset 14, the braking power being proportional to the angle in the opposite direction adopted by the pedals of the crankset 14. A so-called "Dutch" bicycle is thus simulated. Figure 5 shows the isometric lines of pedaling power Pssp user required to maintain constant the speed v of the vehicle 1, in the plane indexed by the speed v on the abscissa and the slope Slo on the ordinate. The isometric lines of pedaling power Pssp user required to maintain the speed v are generally of the same shape as the isometric lines of power Pssp of the motor 7, with a value increasing with the slope Slo and the speed v. One of the isometric lines of pedaling power corresponds to a zero effort of the user (Pssp user = 0), and is therefore the freewheel line FW of the crankset 14.By matching the two freewheel lines FW, of the motor 7 and the crankset 14, a behavior close to that of a real muscle-powered cycle is emulated at low power P. user . Said isometric lines of pedaling power Pssp user may in particular be identical in shape to the isometric lines of power of the motor Pssp mot =Pload(Xi). Conversely, it is possible to adjust the behavior of the motor 7 as a function of the pedaling power Puser. For example, in the area around the freewheel line FW, the gradient of pedaling power Pssp-user may be greater, with isometric lines closer together (“pinch” in the direction of the line FW) in the power graph of the pedaling power P ssp usernecessary to maintain the speed v. Thus, in the range of powers supplied by the user Puser and by the motor 7, the range of powers supplied by the user Puser being relatively more spread out than the corresponding range of powers of the motor 7, a great precision in the piloting in speed v is possible: a large variation in pedaling power Puser then corresponds to a small variation in power Ptot at the level of the motor 7. Conversely, in the range of large powers supplied by the user Puser and the motor 7, the power control can be less precise: a small variation in pedaling power Puser then corresponds to a large variation in power Ptot delivered at the level of the motor 7. Thus, the sensitivity of the effort required of the driver as a function of the speed v or the slope Slo varies greatly between low and high speeds.As a result, for maneuvers and traffic at low speed v, the control of speed v by means of the power applied to the pedal Puser is more precise. Conversely, at high speed v, when the precision of the speed control θ' is less important, the control is less precise but nevertheless allows a large range of speeds v to be reached. The pedaling power P. userspreads over a range of values lower than that of the power of the motor 7, the motor 7 being able to provide a power of the order of a few thousand watts, while the user can only provide a maximum power of a few hundred watts. The control means 25 are configured to accelerate the vehicle 1, by imposing an acceleration power setpoint Ptot sp greater than the previous setpoint, if the instantaneous power applied by the user Puser on the pedals is greater than the instantaneous power Pssp user necessary to maintain the speed v of the vehicle 1 constant. Conversely, the control means 25 are configured to decelerate the vehicle, by imposing an acceleration power setpoint Ptot sp lower than the previous setpoint, if the instantaneous power applied by the user Puser on the pedals is lower than the instantaneous power necessary to maintain the speed of the vehicle P constant ssp user.According to a particular embodiment, when the measured power of the set of forces Pload(t) opposing or contributing to the advance of the vehicle is positive, the instantaneous power required to maintain the vehicle speed Pssp user constant is positive, and the instantaneous power applied by the user Puser is greater than the instantaneous power required to maintain the vehicle speed P constant. ssp user ^^ ^^ ^^ ^^ ^^ ≥ ^^ ^^ ^^ ^^ ^^ ^^ ^^ ^^the acceleration power setpoint Pacc sp follows the following relationship, in which the acceleration power setpoint Pacc, sp is the product of an acceleration coefficient A and the difference between the power applied by the user Puse and the power Pssp user to be applied by the user on the pedals 14 to maintain the speed v of the vehicle 1 constant: To maintain the speed v constant, the user must apply a pedaling power Puser strictly equal to the power value of the set SSmap of stationary speeds. In this embodiment, if the user stops pedaling (Puser = 0), the motor 7 will decelerate the vehicle 1 with a negative acceleration power setpoint proportional to the pedaling power Pssp user necessary to maintain the speed of the vehicle 1. The acceleration coefficient A is advantageously equal to the quotient between, on the one hand, the difference between a maximum power of the vehicle engine Pmax vehicle and the instantaneous power of the motor 7 necessary to maintain the speed of the vehicle Pload(t) constant, and on the other hand, the difference between a maximum power developed by the user Pmax user and the instantaneous power necessary to maintain the speed of the vehicle Pssp user constant: With this formula, the acceleration coefficient A is increasingly important when the power to be developed by the user to maintain constant speed P ssp user approaches the maximum power developable by the user P max user and becomes low conversely when the power of the engine 7 to maintain constant the speed Pload(Xi) approaches the maximum power developable by the engine Pmax vehicle. According to an alternative embodiment, the acceleration coefficient can be fixed, and be worth for example the quotient between the maximum power developable by the engine P max vehicle and the maximum power developable by the user P max user : The maximum power developable by the engine Pmax vehicle is given by the manufacturer of the engine 7, and corresponds in particular to a power value that the engine 7 can maintain safely without damage. The maximum power developable by the user Pmax user is on the other hand to be evaluated and / or configured. For example, when a user uses the vehicle 1 for the first time, he can either enter an estimate of his sporting level, mainly in cycling, in particular by placing his abilities on a scale of 1 to 10 for example, where 10 would be an experienced sportsman and 1 a beginner, as well as other data such as his height, age etc. The maximum power developable by the user Pmax user is then deduced from a table based on the values given by the user. Alternatively, the maximum power developable by the user P max usercan be determined during a preliminary calibration step, vehicle 1 stationary. During this calibration, the user must maintain a fixed cadence while an increasing resistive torque is applied to the pedal assembly 14. The control unit UC then records the power at which the cadence decreases and deduces therefrom a maximum power value that can be developed by the user. When the measured power of the set of forces Pload(t) opposing or contributing to the advance of the vehicle is positive, the instantaneous power necessary to maintain the vehicle speed Pssp user constant is positive, the measured load power Pload(t) is positive, and the instantaneous power applied by the user to the pedal assembly 14 is strictly less than the instantaneous power Pssp user necessary to maintain the speed v of the vehicle 1,^ ^ ^^ ^^ ^^ ^^ < ^^^^ ^^ ^^ ^^ ^^ ^^ ^^The acceleration power setpoint Pacc sp is equal to the product of the measured power Pload(t) of the set of forces Fload opposing or contributing to the vehicle's forward motion multiplied by the difference between the instantaneous power applied by the user Puser and the instantaneous power required to maintain the vehicle's speed Pssp user constant, divided by the instantaneous power required to maintain the vehicle's speed Pssp constant: Thus, when the power developed by the user is equal to the power required to maintain the vehicle speed Puser = Pssp constant, we have a zero power acceleration setpoint, in line with the previous formula. When the power Puser developed by the user is zero (pedaling stops), the power setpoint is equal to the opposite of the load power Pload(t) and the speed v of vehicle 1 is maintained. In this embodiment, when the measured load power Pload(t) and / or the instantaneous power required to maintain the vehicle speed Pssp user constant is negative, the acceleration power setpoint Pacc sp is equal to the difference between, on the one hand, the product of the acceleration coefficient A and the power developed by the user Puser and the measured load power Pload(t): With these three formulas, the acceleration is continuous over all the values of the state variables Xi with a behavior close to that of a classic invoice cycle, without gear changes, and the user feels the forces F load opposing or contributing to the advance of the vehicle 1. The powers achievable by the engine 7 are further indexed to the powers developable by the user at the pedal assembly 14. The control device 100 according to the invention allows continuous control of the speed v of the vehicle 1, in particular with control without any perceived change in gears, over a wide range of speeds v. Notations[1] Ptot total power exerted by motor 7 on the wheels (known via current i)[2] Pacc part of the power devoted to the acceleration of the vehicle[3] Ptot sp total power setpoint[4] Pacc sp acceleration power setpoint[5] Pload(t) load power, exerted by Fload the set of forces on motor 7 (given by Ptot - mva)[6] Pssp mot = Pload(Xi) theoretical power of motor 7 to be applied to maintain speed v at a given set of state variables Xi[7] Pssp user pedaling power on pedal 14 to be applied by the user to maintain speed v[8] Pacc sp acceleration power of the setpoint motor[9] Puser power exerted by the user on pedal 14

[0010] Pmax vehicle maximum engine power 7

[0011] Pmax user maximum pedaling power of the user

[0012] Xi state variables representing the Fload

[0013] v speed (element of Xi), represents the drag in the air

[0014] Slo slope (element of Xi), represents changes in gravitational potential

[0015] a acceleration (dv / dt), m mass of the vehicle, mva = Pacc part of power Ptotconverted into kinetic energy (d(½ mv²) / dt)

[0016] FW line, i.e. a continuous set of state variable sets Xi, freewheeling where Pssp user=0 and / or Pload(Xi)=0

[0017] P1; P2; P3; P4 power values Pload(Xi) to be applied by motor 7 to maintain speed v for the isometric lines of Fig. 4

[0018] PU1; PU2; PU3; PU4 Pssp user power values to be applied by the user to the pedal 14 to maintain speed v for the isometric lines of Fig. 5

Claims

CLAIMS1. Device for controlling at least one electric motor (7) of a vehicle (1), the vehicle (1) comprising:- at least one pedal assembly (14) associated with means for estimating the instantaneous power (Puser) applied by a user (U) to the pedal assembly (14);- means for estimating (23) state variables (Xi) representative of the value of forces opposing or contributing to the forward movement of the vehicle (1) and- means for controlling (25) the power applied to the at least one electric motor (7);characterized in that the control means (25) comprise an electronic memory in which is stored a set of stationary regimes (SSmap) of the pedal assembly 14 defining the instantaneous power (Pssp user) to be applied by the user to the pedal assembly (14) to maintain the speed (v) of the vehicle (1) constant as a function of the values ​​of the state variables (Xi);and in that the control means (25) are configured to:* estimate the state variables (Xi) and deduce therefrom the instantaneous power (Pssp user) to be applied by the user to the pedal assembly (14) to maintain the speed (v) of the vehicle; (1),* accelerate the vehicle (1) if the instantaneous power applied by the user (Puser) to the pedals (14) is greater than the instantaneous power required to maintain the vehicle speed constant (Pssp user) at the pedals (14); and* decelerate the vehicle (1) if the instantaneous power applied by the user (Puser) to the pedals (14) is less than the instantaneous power required to maintain the vehicle speed constant (Pssp user) at the pedals (14).

2. Device for controlling at least one electric motor of a vehicle according to claim 1, characterized in that the set of stationary regimes (SSmap) is such that for the sets of state variables (Xi) for which the power (Pssp user) to be applied by the user to the pedal assembly (14) to maintain the speed of the vehicle (1) is zero (FW), the power (Pload(Xi)) necessary for the motor (7) to maintain the speed (v) of the vehicle (1) constant is also zero.

3. Device for controlling at least one electric motor of a vehicle according to claim 1, in which the acceleration or deceleration of the vehicle (1) is carried out by imposing an acceleration power setpoint (Pacc sp) respectively positive or négative.

4. Device for controlling at least one electric motor of a vehicle according to claim 3, characterized in that it further comprises means for estimating a load power (Pload(t)) corresponding to the power exerted by a set of forces (Fload) opposing or contributing to the advance of the vehicle (1) and in lequelwhen the load power (Pload(t)) is estimated to be positive and the instantaneous power applied by the user (Puser) is greater than the instantaneous power required to maintain the vehicle speed (Pssp), the acceleration power setpoint (Pacc, sp) is the product of an acceleration coefficient (A) and the difference between the power applied by the user (Puser) and the power (Pssp user) to be applied by the user to the pedals (14) to maintain the speed (v) of the vehicle (1) constant.5.Device according to claim 4, in which, when the measured power of the set of forces (Pload(t)) opposing or contributing to the advance of the vehicle is estimated to be positive, that the instantaneous power necessary to maintain the speed of the vehicle constant (Pssp user) is positive, and that the instantaneous power applied by the user (U) to the pedal assembly (14) is strictly less than the instantaneous power (Pssp user) necessary to maintain the speed v of the vehicle (1), the acceleration power setpoint (Pacc sp) is equal to the product of the measured power (Pload(t)) of the set of forces (Fload) opposing or contributing to the advance of the vehicle multiplied by the difference between the instantaneous power applied by the user (Puser) and the instantaneous power necessary to maintain the speed of the vehicle constant (Pssp user), divided by the instantaneous power necessary to maintain the speed of the vehicle constant (Pssp).

6. Control device according to one of claims 4 or 5, wherein when the measured load power (Pload(t)) and / or the instantaneous power necessary to maintain the vehicle speed (Pssp user) constant is negative, the acceleration power setpoint (Pacc sp) is equal to the difference between, on the one hand, the product of the acceleration coefficient (A) and the power developed by the user (Puser) and the measured load power (Pload(t)).

7. Control device according to one of claims 4 to 6, wherein the acceleration coefficient (A) is equal to the quotient between, on the one hand, the difference between a maximum power of the vehicle engine (Pmax vehicle) and the load power (Pload(t)), and on the other hand, the difference between a maximum power developed by the user (Pmax user) and the instantaneous power necessary to maintain the vehicle speed (Psspuser) constant at the pedal assembly (14).8.Control device according to one of the preceding claims, in which the state variables (Xi) comprise at least one parameter from among the slope (Slo) and the speed (v) of the vehicle (1).

9. Control device according to the preceding claim, in which the state variables (Xi) further comprise at least one parameter from among: the total weight of the vehicle (1), the type of road on which the vehicle (1) is moving, and the relative wind speed with respect to the vehicle (1).

10. Vehicle of the velomobile type, characterized in that it comprises a control device (100) according to one of the preceding claims and at least one electric motor (7) controlled by said control device (100).

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