electric scooter

Abstract

The invention relates to an electric scooter comprising a drive unit (7), a battery unit (6) that stores electrical energy and provides it to the drive unit (7), and a solar unit (4). The solar unit (4) comprises a plurality of solar cells (41), wherein the solar cells (41) are electrically connected in series in several solar cell rows (46), each solar cell row (46) being assigned a voltage regulator (48) which is designed and configured to provide a constant direct current on its output side. The voltage regulators (48) of the different solar cell rows (46) each provide the same constant direct current.Furthermore, the electric scooter includes a controller (51) which is connected on the input side to the outputs of the voltage regulators (48) and is designed to provide electrical energy from the solar unit (4) or the battery unit (6) of the drive unit (7), or to provide electrical energy from the solar unit (4) of the battery unit (6).

Description

The invention relates to an electric roller.Electric scooters have become widely used in road traffic, in particular in interior cities. Typically, an electric roller is a roller that is driven by an electric motor. Alternative designations are also E-Scooters or E-Tretrollers. The scooters are modeled on a classic scooter, wherein the electric scooter has a battery and an electric drive. To charge the battery, the entire electric roller is connected to a charging cable or the battery is removed manually from the electric roller and charged separately via a battery charger. In this case, the user must fundamentally connect the electric scooter to the power grid at home or at another location.It is known to provide an electric roller with solar cells which can charge the battery. However, conventional electric scooters with solar cells have the problem, among other things, that the solar cells provide insufficient energy for charging the battery.DE 10 2020 116 490 A1 discloses a photovoltaic device for an impeller. Photovoltaic cells are arranged on a front and / or rear wheel in each case in a plurality of radially running strings. The photovoltaic cells can have different shapes in order to adapt to the respective space on the wheel.WO 2016 / 184 925 A1 discloses a wheel which can be installed in bicycles and whose side surfaces are equipped with solar cells. The solar cells are each divided into sectors on the wheel and electrically connected to one another in a sector to form a circuit. An MPPT unit can be arranged in each sector, which provides efficient operation of the solar cells.FR 3 111 111 A1 relates to an electric vehicle, for example a scooter, which is equipped with a control unit. The control unit serves for safety of the driver and triggers a braking mechanism in the event of a risk detection. The vehicle can be equipped with a solar panel.It is an object of the invention to provide an improved electric roller provided with solar cells, in which efficient use of solar energy is made possible.This object is achieved by an electric roller having the features of claim 1. Embodiments of the invention are set forth in the dependent claims.According to this, the invention contemplates an electric scooter having a drive unit and a battery unit. The battery unit stores electrical energy and provides it to the drive unit. The electric roller further comprises a solar unit having a plurality of solar cells. The solar cells are electrically connected in series in a plurality of solar cell rows, each of which is assigned a voltage regulator. The voltage regulator is provided and designed to provide the same constant DC voltage on the output side. In addition, the electric scooter has a controller (e-scooter controller) which is connected on the input side to the outputs of the voltage regulators. The controller is configured to provide electrical energy from the solar unit or the battery unit of the drive unit or to provide electrical energy from the solar unit of the battery unit. In this sense, the controller is a control device for energy distribution.The invention is based on the concept of connecting different solar cell rows to the controller in such a way that the controller can always be supplied with a constant voltage by the solar unit. The voltage regulators serve as compensating elements by means of which voltages of different magnitude of the individual solar cell rows are equalized.The invention enables the electric scooter to be efficiently operable and can contribute to reducing the environmental effects of the traffic sector. This is achieved by effectively charging the battery with the current generated by the solar cells mounted on the electric scooter. This reduces the need to charge the electric scooter at the outlet and makes a contribution to a higher percentage of the use of renewable energies in the mobility sector.In this case, the voltage regulator is operated as a constant voltage source, which makes it possible in an efficient manner to adapt the charging process, for example.For example, a low voltage generated on a solar cell row in shadow can be amplified by the voltage regulator, and at the same time a high voltage generated on a sunny side can be reduced. Alternatively, both sides can be increased to a same superordinate voltage level.According to the invention, the electric scooter has a steering rod with a triangular, square, pentagonal or hexagonal cross-sectional area. The steering rod forms three, four, five or six side surfaces, wherein at least one of the side surfaces is provided with one of the solar cell rows. In alternative embodiments, the steering rod can also be provided with more side surfaces.It can also be provided that each side surface is provided with a solar cell row. It can be provided that one solar cell row extends over the entire side surface, as well as that a plurality of solar cell rows are formed on one side surface.The use of the voltage regulators moreover makes it possible for solar cell rows with different numbers of solar cells to also be used by adjusting the voltage. Accordingly, one embodiment of the invention provides that at least two solar cell rows have a different number of solar cells. Since a solar cell row with a large number of solar cells generates a higher voltage than a solar cell row with few cells, the use of the voltage regulators also allows smaller areas on the electric roller to be used for the generation of energy and thus to increase the efficiency of the generation of power.In a further embodiment of the invention, it is provided that a blocking diode is connected to an end of a solar cell row connected to the voltage regulator. The blocking diode is provided and configured to prevent a reverse electric current to the solar cells and provides that the electric current flows only in the direction of the controller. In this case, a bypass diode is connected in parallel with each solar cell row. If a solar cell fails and no longer conducts current, the parallel connection allows a bypass to be formed and the current can bypass the defective solar cell. In this case, the diode also prevents an unwanted reverse current. Alternatively, it can be provided that a bypass diode is connected in parallel to a defined number of solar cells. A corresponding bypass effect can also be advantageous if a solar cell is in shadow and cannot generate electrical energy.The solar cells may be secured to the various surfaces of the roller with an adhesive.In a further exemplary embodiment, the electric scooter has a running board and a central part. The top side of the running board has a solar cell row.The central part can have an upper side and at least two side surfaces, which are each provided with a solar cell row. Thus, the central part can also be used efficiently for power generation. The voltage regulators make it possible in an efficient manner in this case for, for example, a lower power generation at the side surfaces compared to other surfaces on the electric scooter to be compensated for.The central part can have a square cross-sectional area if the central part has, for example, two side surfaces, an upper side and a lower side. However, in alternative exemplary embodiments, it can also be provided that the central part is triangular in cross section by having two side faces and an upper side or a lower side.In a further exemplary embodiment, the electric scooter has a load management system for controlling the controller. The load management system is connected to sensors which are arranged on the drive unit, the solar unit, the battery unit and / or on a further component of the electric scooter. The load management system can decide on the basis of the sensor data about which the power supply of the drive unit is supplied and correspondingly regulate the controller. The load management system thereby serves an efficient use of energy, wherein the controller forms the switching center via which the electric current flows in the electric scooter. Thus, the electrical energy can be conducted through the controller from the solar unit to the battery unit or can be conducted from the solar unit and / or the battery unit via the controller to the drive unit.In a further exemplary embodiment, the electric roller can also be connected to a socket via a cable and charged by a mains voltage. In this case, the controller can conduct the mains voltage to the battery unit in order to charge the latter. This may be useful in particular when there is not sufficient solar energy available, for example at night.In a further embodiment variant, the controller has a microcontroller. The microcontroller is designed to record information for the provision of energy and to communicate it with the load management system and / or the solar unit and / or the battery and / or the drive unit. The controller is part of the load management system in this case can be connected to at least 3 elements, namely the solar unit, the battery unit and the drive unit. For example, the energy consumption may be coupled to how much energy is provided by the solar unit. Furthermore, the microcontroller can adapt the energy distribution in the electric scooter depending on external factors. External factors can represent, for example, the external temperature, which are detected, for example, by sensors and on the basis of which the microcontroller adjusts the load management system.In a further variant of the invention, the solar unit has sensors for determining the heat load, the voltage and / or the electric current. In this case, it can be provided that the sensor data are passed on to the controller.In a further variant of the invention, each solar cell row has a maximum power point module which is provided and designed to set the electrical power of the respective solar cells. The maximum power point module can form an adaptive load resistor, for example, which ensures efficient operation of the solar cells and is abbreviated below as a MPPT (maximum power point tracker). The MPPT may also serve to adjust the performance of the solar cells with respect to external conditions such as ambient temperature. For example, the MPPT can also be connected to corresponding sensors arranged on the solar cells.In a further exemplary embodiment, the battery unit has a battery management system. The battery management system is to control charge and discharge of the battery.The battery unit may have a plurality of sensors which are designed to measure the temperature, the voltage and the electrical current across the battery cells and to provide the data to the battery management system.In a further exemplary embodiment, the electric scooter has a user interface. The user interface is designed to process and display information from the load management system to the user. In this case, it can additionally be provided that the user interface also processes information from the battery management system and displays it to the user.In a further exemplary embodiment, the controller has an inverter which is designed to provide an AC voltage to the drive unit. This is particularly advantageous in the case where the drive unit has an AC motor. The controller is used to convert the DC voltage provided by the battery unit or the solar unit into an AC voltage and to make it available to the AC motor.The invention is explained in more detail below with reference to the figures of the drawing on the basis of a plurality of exemplary embodiments. The following are shown: FIG. 1 is a perspective view of an electric scooter provided with solar cells and having a handlebar, a middle part and a running board; FIG. 2 shows a schematically illustrated switching structure of the solar cells, wherein the solar cells are arranged in solar cell rows and are connected to bypass diodes and a blocking diode; FIG. 3 is a block diagram showing the connection of the solar cells to a battery and a drive unit; FIG. 4 is a diagram of the various components of the electric roller; FIG. 5 shows a perspective view of the steering rod of the electric roller of FIG. 1 ; FIG. 6 shows a perspective view of the central part of the electric roller of FIG. 1 ; and FIG. 7 shows the running board of the electric roller of FIG. 1 in a side view and a view from above.FIG. 1 shows the structure of an electric roller provided with solar cells 41 for generating electric energy. The electric scooter comprises a steering rod 1, a middle part 2 and a running board 3. The handlebar 1 connects a handlebar 11 for controlling the scooter to a front wheel 12, and a plurality of solar cells 41 are disposed on the handlebar 1. Three side surface areas 13 with solar cells 41 arranged thereon extend in the vertical direction along the steering rod 1.The running board 3 serves to allow a user to stand on the same safely while driving and connects the front wheel 12 to a rear wheel 31, which can be mechanically reinforced for this purpose. The running board 3 and the handlebar 1 are connected by the middle part 2. The central part 2 has an upper side 21 and two side surfaces 22, which are each provided with solar cells 41. The running board also has an upper side 32 with solar cells arranged thereon. For a more detailed illustration of the individual parts, reference is made to FIGS. 5-7.The solar cells 41 attached to the electric roller can be mounted to the electric roller both during the manufacturing process of the electric roller and subsequently. It can be provided here to cover most of the surface of the electric roller, i.e. for example at least 70%, preferably over 80% or 90%, of all surfaces of the electric roller with solar cells 41.The connection of the solar cells 41 to form solar cell rows 46 is illustrated in FIG. 2. The solar cells 41 are basically electrically connected in series so as to form solar cell rows 46. The solar cell rows 46 can have a different number of solar cells 41. By way of example, FIG. 2 illustrates solar cell rows 46 having two, three and four solar cells 41. Solar cell rows 46 with a significantly larger number of solar cells 41 are also possible.In a solar cell row 46, a bypass diode 42 is connected in parallel with each solar cell 41. The bypass diode 42 serves to prevent the failure of an entire solar cell row 46 in the event of failure of a solar cell 41. If, for example, a solar cell 41 fails, it can no longer conduct current. By connecting the bypass diode 42 in parallel, a bypass is formed and the current can bypass the defective solar cell 41. A corresponding bypass effect can also be advantageous if an individual solar cell 41 is in shadow and cannot generate electrical energy. In this case, the bypass diode 42 also prevents an undesired reverse current in the bypass.In this example, a bypass diode 42 is connected in parallel with each solar cell. Alternatively, it can be provided that, in order to save bypass diodes 42, a bypass diode 42 is connected in parallel in each case to a defined group of solar cells 41. Accordingly, in the event of a failure of one solar cell 41, the further solar cells 41 of the group are respectively missing, which are connected in series with the defective solar cell 41 or the solar cell 41 located in the shadow.The solar cell row 46 has a first end 44 and a second end 45. The first end 44, which is symbolized here by a plus pole, is connected to a maximum power point module (MPPT) 47 and a voltage regulator 48, as explained with reference to FIG. 3. The maximum power point module 47 forms, for example, an adaptive load resistor which ensures efficient operation of the solar cells 41 and is abbreviated below as MPPT 47 (maximum power point tracker). A blocking diode 43 is arranged at the first end 44. The blocking diode 43 is connected in series with the solar cells 41 and the bypass diodes 42 so that the current must flow through the blocking diode 42 in each case to get from the solar cells 41 to the MPPT 47 and the voltage regulator 48, respectively. The second end 45 of the solar cell row 46, represented by the negative pole, is a ground terminal.Referring to FIG. 3, a block diagram illustrates the connection of the solar cells 41 to the battery 61 and the electric motor 71. The various solar cell rows 46 are each connected to an MPPT 47 and a voltage regulator 48 and together with a solar switch 49 form the solar unit 4.The MPPT 47 serves to adjust the electric power of the respective solar cells 41 to the external conditions. Here, the MPPT 47 always adjusts a load resistance to make the power provided by the solar cells 41 as large as possible. Downstream of the MPPT 47 is a voltage regulator 48.The voltage regulator 48 ensures that a constant DC voltage is provided in each case. In this case, the voltage regulators 48 of the different solar cell rows 46 each provide a constant voltage at the solar cell rows. The voltage regulators 48 serve as compensating element, by means of which voltages of different magnitude of the individual solar cell rows 46 can be matched. Depending on the situation (for example, solar radiation, shadows or damage), different solar cell rows 46 generate different amounts of energy. The respective voltage regulator 48 compensates the different voltages of the individual solar cell rows 46 to a constant voltage level. At the same time, the use of the voltage regulators 48 allows the solar cell rows 46 to each have different numbers of individual solar cells 41. In further exemplary embodiments, which are not shown, the MPPT 47 and the voltage regulator 48 are configured in combination in one component.Behind the respective voltage regulators 48, the lines of the solar cell rows 46 are brought together and connected to a solar switch 49. If necessary, the solar switch 49 can disconnect the connection of the solar cells 41 to the rest of the electric roller. A disconnection can be useful, for example, if the battery 61 is already fully charged and no current is consumed by the electric motor 71. The solar switch 49 can have control, for example, via a microcontroller, not shown.Behind the solar switch 49, a controller 51 (e-power controller) is arranged. The controller controls the supply of the electric power. Depending on the setting of the controller 51, the electrical energy is supplied to the electric motor 71 either from the battery unit 6 and / or from the solar unit 4 via the controller 51. Alternatively, the electrical energy can also be supplied via the controller 18 from the solar unit 4 to the battery 61 (charging when parking the electric scooter) or to the drive unit. In an exemplary embodiment which is not illustrated, the electric roller can also be connected to a socket via a cable and can be charged by a mains voltage. This may be useful in particular when there is not sufficient solar energy available, for example at night.FIG. 4 shows an illustration of the energy and management system of the electric scooter. In this case, the four frames illustrated symbolise the solar unit 4, a battery unit 6, a load management system 5 and a drive unit 7.The solar unit 4 comprises the solar cells 41 connected to at least two solar cell rows 46, the solar switch 49, a plurality of sensors 411 and a solar control controller 412 connected thereto, which processes the sensor data and is designed to enable efficient and reliable energy generation of the solar cells 41. To this end, the solar control controller 412 is also connected to the solar cell array 46. In this illustration, the MPPT 47 and the voltage regulator 48 are not shown. However, it is provided that the solar control controller 412 is connected to both components. In particular, it is provided that the solar control controller 412 is connected to the MPPT 47 and, accordingly, the setting of the operation of the solar cells 41 can be controlled as a function of the sensor data. In addition to the data of the sensors installed in the solar cell rows 46, the control controller 412 receives data such as load demand and power limitation from the controller 51. Based on the data, the control controller 412 determines the optimum power output and controls the voltage of the solar cell rows 46 accordingly in combination with the MPPT 47. In addition, information on the state of the solar cells 41 can be displayed to the user by the data. For this purpose, it can be provided that the control controller 412 is directly connected to the controller 51, illustrated by a dashed line.The battery unit 6 includes the battery 61 for storing the power. The battery unit 6 further comprises a battery management system 62, which is realized, for example, by a microcontroller. The battery management system 62 is connected to a plurality of sensors 63 that measure the temperature of the battery 61, the voltage, and the charging and discharging current, respectively. In the event that no energy is generated by the solar cells 41, the battery management system 62 ensures battery power to supply power to the drive unit 7 within the safe operating limits. Moreover, the battery management system 62 is connected to a battery switch 64 disposed between the battery 61 and the controller 51. Accordingly, the discharge or charge of the battery 61 can be interrupted by the battery switch 64. In the event of imminent overheating, for example, the temperature can be determined via the sensors 63 and passed on to the battery management system 62, with the result that the battery switch 64 is opened by the battery management system 62 and the connection to the controller 51 is interrupted. In another case, the battery switch 64 may break the connection, for example, when no current is consumed by the drive unit 7 and at the same time the battery 61 has already been fully charged by the solar unit 4. In alternative embodiments, not shown, the battery management system 62 may also be directly connected to the controller 51 as shown by a dashed line.The load management system 5 comprises the controller 51, a voltage converter 52 and a user interface 55. The controller 51 is connected to the user interface 55 and sensors 72 of the drive unit 7 and controls the current distribution between the solar unit 4, the battery unit 6 and the drive unit 7 in dependence thereon.The user interface 55 is connected to the controller 51 via the voltage converter 52. Via a CAN bus system 551 (controller area network), input variables are recorded via an input 53 and information is prepared to the user via an output 54. Input variables for acceleration or braking are input via the input 53. This can be done, for example, by means of a rotary handle on the link 11 and a brake lever provided with electronics. At the same time, information about the range or the rotational speed, for example, can be presented to the user via the output 54. In this case, the user is informed about the optimum speed and the maximum range with the aid of color schemes on a user interface. In addition, the user can be warned when the battery level is low and possibly be stimulated to perform an emergency stop in order to avoid further damage to the entire system. For this purpose, it can be provided that the electric roller gradually reduces the speed until it completely stops.The drive unit 7 has the electric motor 71 as a drive, a motor control 73 assigned to the drive and a plurality of sensors 72. The sensors 72 measure mechanical quantities such as the rotation of the wheels or of the rotor on the electric motor 71 and electrical quantities such as voltage, current and electric flux.The motor controller 73 provides safe operation of the motor and controls its speed and load.FIGS. 5, 6 to 7 visualize the three main mechanical components of the electric scooter: steering bar 1, middle part 2 and running board 3. FIG. 5 shows the steering bar 1 with solar cells 41 located thereon. The solar cells 41 used for this application can be, for example, monocrystalline, polycrystalline or perovskite solar cells. In this case, they can be rigid or flexible.The upper end of the handlebar 1 is formed by a handlebar 11 and the lower end by the front wheel 12, and the handlebar 1 is provided with a plurality of solar cells 41. The solar cells 41 are arranged on three lateral surfaces 13 of the steering rod 1 which are situated at an angle to one another, wherein the surfaces 13 form a triangle in cross section, wherein in alternative exemplary embodiments further cross-sectional shapes, such as, for example, square, pentagonal or hexagonal cross-sectional shapes, are also provided. In this exemplary embodiment, a respective solar cell row 46 extends on a side surface 13.FIG. 6 shows the middle part 2, and the middle part 2 has an upper side 21 and two side surfaces 22, which are each provided with a plurality of solar cells 41. The solar cells 41 on the side surface 22 and on the top side 21 each form a solar cell row 46. the middle part 2 is square in cross section, wherein in alternative exemplary embodiments further cross-sectional shapes, such as triangular, pentagonal or hexagonal cross-sectional shapes, are also provided.In an embodiment not shown, the central part 2 is provided with a hinge. Alternatively, the middle part 2 has a hinge at the transition to the running board 3 or the steering rod 3. The hinge allows the electric roller to be folded such that the steering rod and the running board lie on top of one another.FIG. 7 shows the running board 3 and the rear wheel 31 connected thereto in a side view and a view from above. From the view from above, it can be seen that a plurality of solar cells 41 are arranged on the upper side of the running board 3. The solar cells 41 on the upper side of the running board form a solar cell row 46 in this case. In further exemplary embodiments, it can be provided that the solar cells 41 are arranged on the running board 3 in a plurality of solar cell rows 46. The battery unit 6, the controller 51 and the load management system 5 can be arranged in the running board 3 or in the middle part 2. Alternatively, the load management system 5 can be arranged on the steering arm 11.

Claims

An electric scooter, comprising: - a drive unit (7), - a battery unit (6) which stores electrical energy and provides it to the drive unit (7); - a solar unit (4) having a plurality of solar cells (41), wherein ◯ the solar cells (41) are electrically connected in series in a plurality of solar cell rows (46), and ◯ each solar cell row (46) is assigned a voltage regulator (48) which is provided and designed to provide a direct voltage on the output side, wherein the voltage regulators (48) of the different solar cell rows (46) each provide the same constant direct voltage, - a controller (51) which is connected on the input side to the outputs of the voltage regulators (48) and designed to provide electrical energy from the solar unit (4) or the battery unit (6) to the drive unit (7), or to provide electrical energy from the solar unit (4) to the battery unit (6), characterized in that, the electric roller having a steering rod (1) with a triangular, square, pentagonal or hexagonal cross-sectional area, so that the steering rod (1) forms three, four, five or six side surfaces (13), wherein at least one of the side surfaces is provided with one of the solar cell rows (46).Electric roller according to Claim 1, characterized in that at least two solar cell rows (46) have a different number of solar cells (41).Electric scooter according to claim 1 or 2, characterised in that the steering bar (1) has a triangular cross-sectional area, wherein the steering bar (1) forms three side surfaces (13) and at least one of the side surfaces (13) is provided with one of the solar cell rows (46).Electric roller according to one of the preceding claims, characterized in that each side face (13) is provided with a solar cell row (46).Electric roller according to one of the preceding claims, characterized in that a blocking diode (43) is connected in each case to an end (44) of a solar cell row (46) which end is connected to the voltage regulator (48) and is provided and designed to prevent a reverse-directed electric current to the solar cells (41), and in that a bypass diode (42) is connected in each case in parallel to each solar cell (41) of a solar cell row (46).Electric roller according to one of the preceding claims, characterized in that the electric roller has a running board (3) and a central part (2), wherein the upper side of the running board (3) has a solar cell row (46).Electric roller according to claim 6, characterised in that the central part has an upper side (21) and at least two side surfaces (22), which are each provided with a solar cell row (46).Electric scooter according to one of the preceding claims, characterized in that the electric scooter has a load management system (5), wherein the load management system (5) is connected to sensors (72) arranged on the drive unit (7) and is designed to control the current supply of the drive unit (7) by the controller (51) as a function of the sensor data.Electric scooter according to one of the preceding claims, characterized in that the controller (51) has a microcontroller which is designed to record information for the provision of energy and to communicate with the load management system (5) and / or the solar unit (4).Electric roller according to one of the preceding claims, characterized in that the solar unit has sensors (411) for determining the heat load, the voltage and / or the electric current.Electric roller according to one of the preceding claims, characterized in that each solar cell row (46) has a maximum power point module (47) which is provided and designed to set the electrical power of the respective solar cells (41).Electric scooter according to one of the preceding claims, characterized in that the battery unit (6) has a battery management system (62) which is provided and designed to control the battery charge and discharge, wherein the battery unit (6) has a plurality of sensors (63) which are designed to measure the temperature, the voltage and the electrical current of the battery (61) and to provide the data to the battery management system (62).Electric scooter according to one of the preceding claims, characterized in that the electric scooter has a user interface (55), wherein the user interface (55) is designed to work up and display information from the load management system (5) to the user.

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