DE202022102768U1 - Electromagnetic current generator for a wheel - Google Patents

Abstract

Electromagnetic current generator (1), which has a rotatably mounted stator (3) with an eccentric center of mass (21) and a rotor (4) which can be rotated relative to the stator (3), and which is mounted on a wheel (17) in this way by means of the wheel (17) movable object can be mounted, that when the wheel (17) turns, the rotor (4) rotates relative to the stator (3) and the power generator (1) thereby generates power in a generator mode, characterized in that the power generator ( 1) includes the following:
- A first means, which is designed to detect whether the stator (3) is overturning, comprising
- a means for determining the speed of the wheel (17) and/or the rotor (4),
- a means for determining the differential speed of the rotor (4) compared to the stator (3),
- a means for comparing the determined speed of the wheel (17) and/or the rotor (4) and the determined differential speed of the rotor (4) with respect to the stator (3), and
- A means for detecting the overturning of the stator (3) from the fact that the determined speed of the wheel (17) and / or the rotor (4) by more than a user-defined first threshold value of the determined differential speed of the rotor (4) compared to the stator (3) deviates,
- and a second means which is designed to end the flashing of the stator (3) in the event that the first means detects a flashover of the stator (3) by applying current to the rotor (4) in this way is that the stator (3) is thereby accelerated.

Description

The invention relates to a power generator in the field of generating electrical energy from the rotary motion of a wheel, the rolling of which moves an object, the electromagnetic power generator being mounted on a wheel in such a way that when the wheel turns, a rotor of the power generator rotates relatively rotates to its stator and thereby the power generator generates electricity.

An electromagnetic power generator according to the invention is an electrical generator, i.e. an electrical machine that converts kinetic energy, in this case the kinetic energy (rotational energy) of the wheel or the kinetic energy of the object moved by the wheel, into electrical energy using electromagnetic induction . Such a power generator is also called a dynamo. The mechanical power is usually supplied to the generator in the form of the rotation of a mechanical shaft. Inside the generator, in an exemplary first variant, there is a concentrically mounted arrangement of a fixed stator (also called stator housing or stand) and a rotor (also called rotor) that can rotate relative to the stator and is driven by the shaft. The rotor usually has one or more permanent magnets or one or more electromagnets (also called field coils or excitation windings) in order to generate a constant magnetic field, and the stator has one or more conductor windings. When the rotor is turned relative to the stationary stator housing, an electrical voltage is induced in the conductor windings of the stator by the circulating DC magnetic field of the rotor, which means that electrical current is generated as a result.

Since only the relative rotational movement between rotor and stator is important, in embodiments with the same effect, the stator with the conductor windings can also be rotated with respect to a stationary rotor, which generates a magnetic constant field, by means of the shaft or another drive. In this case, compared to the first variant, the rotor becomes a stator that has one or more permanent magnets or one or more electromagnets (also called field coils or excitation windings) in order to generate a DC magnetic field, and the stator becomes a rotor that has one or more conductor windings and is rotated with respect to the stator. In both cases, an electrical voltage is induced in the conductor windings (of the stator or rotor) by the relative rotational movement between the rotor and stator or by the circulating DC magnetic field (of the rotor or stator), i.e. electric current is generated.

With a rotating wheel of an object moved by means of the wheel, in particular with the wheels of a motor vehicle rotating relative to a vehicle body, the provision of electrical energy in or on the rotating wheel for an electrical consumer is required for some practical applications in order to function to realize or enable that consumes electrical energy. A first example is the power supply of sensors installed in or on the rotating wheel, which measure various parameters, e.g. tire pressure, temperature or rotational speed, or send signals. Another example is an electric light attached to the wheel that lights up permanently, for example for design reasons, or lights up temporarily, for example to implement a "coming home" function, which involves illuminating the wheel after the vehicle has stopped when it reaches it of the arrival destination for a defined time when exiting the vehicle.

In other applications, an optical display or a warning signal that lights up briefly should be implemented, for example to display different driving modes of the vehicle (such as autonomous or manual driving mode) or to implement a side warning or brake light, to display the direction of travel or the engagement of reverse gear or an optical one To generate a warning signal, for example in the event of an accident of the vehicle or in an emergency vehicle. Another application can be the power supply of an electrically operated mechanical actuator, which is used, for example, to close the gaps between the spokes of a wheel with covers in order to reduce the air resistance of the wheel and/or to open them when braking to cool the brakes.

It is technically complex and disadvantageous for this purpose to transmit electrical energy from outside the rotating wheel, for example from the vehicle body, to the rotating wheel, for example by cable or sliding contacts. Systems are therefore known in the prior art that make electrical energy available in the hub of a vehicle wheel from an energy storage device without requiring structural changes to the wheel or the wheel cover and which, in terms of their basic design, fit on different wheels. In these systems, the electrical energy is provided by batteries. The disadvantage here is that the system is not maintenance-free because the battery discharges over time, so that after a certain period of use the battery is empty and has to be replaced in order to continue using the system. This means additional work for the user, no reliability and additional requirements with regard to the construction of such systems.

It was therefore proposed for such applications to generate the electrical energy in the wheel itself, specifically by means of an electromagnetic power generator arranged in the wheel, which during driving operation obtains the electrical energy from the rotary movement of the wheel. Such systems are better suited for such applications since they can be largely maintenance-free, for example if the electrical energy generated by the electromagnetic power generator is stored in a rechargeable accumulator which is arranged in the wheel.

An electromagnetic current generator arranged in or on the wheel can be implemented in different ways. A first variant requires a constructive or production-related modification of the wheel itself, which is disadvantageous and complex and severely limits the possibility of use, since corresponding systems or modules can only be used in wheels specially adapted for this purpose. In a second variant, a corresponding system or module is mounted on the wheel as an additional component, for example like a wheel cover, which completely or partially covers the axial end face of a wheel radially and circumferentially. For example, wheel covers that include energy generating modules are in the documents DE 20 2018 000 319 U1 and US 2014/0043839 A1 described. However, the implementation in the form of a wheel cover also has disadvantages, which result, for example, from the radial inclination or from the fact that the electrical and electronic components are exposed to external influences. Furthermore, they require an additional design effort for their attachment to the wheel and their possible uses on wheels are limited due to the attachment requirements and the geometric conditions.

From the document DE 20 2018 000 629 U1 a wheel-mounted electromagnetic power generator is known, which is arranged in the cylindrical cavity of the hub of the wheel and can be used on many wheels of different types without increased additional effort in terms of design, manufacture and costs. A corresponding module with such a power generator can easily be adapted to a specific wheel, ie a specific wheel can be retrofitted with a correspondingly adapted module without or without any significant modification of the wheel, which is significantly less complicated than adapting wheels. In this case, the basic structure, the basic components and various components of such systems or modules can preferably always be the same, with the exception of the housing, which can be specifically designed for a specific wheel in an uncomplicated manner. A corresponding module can meet the practical requirements in terms of strength when driving, protection against water, eg splash water and moisture, as well as low and high temperatures.

The electromagnetic power generator described in this document corresponds to the second variant described at the outset, with a rotatably mounted stator with an eccentric center of mass in the form of a pendulum with permanent magnets and a rotor with at least one coil. The rotor is rotated indirectly by the wheel, namely by virtue of the wheel hub to which it is non-rotatably connected, so that when the wheel rolls the rotor rotates together with the wheel, and the stator is arranged to rotate freely relative to the rotor. The stator is not designed to be circularly symmetrical, but has a radially projecting weight part only over part of the circumference, which results in an eccentric arrangement of the center of mass of the stator radially outside the axis of rotation of the stator. An electrical circuit with an energy controller and a chargeable accumulator is connected to the rotor in a rotationally fixed manner, the electrical circuit being connected on the one hand to the current generator and on the other hand to the chargeable accumulator. The body of the system consists of two parts and also includes an electrical load connected to the electrical circuit, the rechargeable battery and the power generator.

The advantage of this known power generator arranged in the wheel hub is that the electrical energy when the object being moved with the wheel is being driven is obtained in the rotating wheel itself and is temporarily stored there in a chargeable accumulator. The system is therefore maintenance-free and fail-safe, since no battery needs to be replaced. Furthermore, no electrical energy has to be conducted to the rotating wheel by means of cables or the like.

In the rest position, ie when the power generator is not generating any electricity, the rotatably mounted stator, designed as a pendulum, is rotated downwards by gravity into a rest position and held there due to its eccentric center of mass. In generator mode, ie when the Stromgenerator generates electricity, the stator is rotated from this rest position into a working position until the torque caused by gravity on the stator corresponds to the torque caused by electromagnetic induction of the current generator on the stator. During regular operation, the deflection of the stator from the rest position is practically static or constant and is determined by the torque generated by the electromagnetic induction of the current generator on the stator. In regular operation of the power generator, i.e. in the power-generating generator mode, the stator does not rotate or roll over while the rotor rotates together with the wheel, but is merely deflected from its rest position to a working position in which this is caused by the eccentric center of gravity of the stator given torque at the stator corresponds to the torque given by the power generation of the power generator at the stator. The stator is held by gravity in the deflected working position with a certain deflection angle compared to the vertical rest position, in which the stator applies the necessary counter-torque for the rotating rotor.

In the context of the invention, however, it was found that in real driving operation of the rolling wheel, the freely rotatably mounted stator can roll over (spin, spin), with the stator no longer being held in a certain angular range due to gravity, but an undesirable one and uncontrolled rotation takes place. It has been found that this effect can already occur on a motor vehicle wheel at a vehicle speed of approx. 60-80 km/h. The trigger for the overturning of the stator is usually an additional acceleration that acts briefly on the stator while driving, for example when driving at high speed, when braking or accelerating the vehicle, when steering abruptly or when impacts occur, for example when driving over a bump or through bumps in the roadway.

The additional acceleration acting on the stator means that it cannot maintain its intended working position, but is deflected even further. Since the stator torque generated by gravity decreases again with increasing angle from a stator deflection of 90° compared to the vertical rest position, this usually leads to the stator being deflected more than 180° compared to the rest position, i.e. overturning. Within the scope of the invention, it was also found that when the vehicle is being driven, a stator that is overturning usually does not automatically return to the working position after the additional acceleration has subsided, in which the torque on the stator due to gravity and the torque on the stator due to induction in the equilibrium, but continues to flip and rotate continuously until the wheel comes to rest or rotates very slowly and the stator has returned to its static rest or operative position.

Such a flashover of the stator has serious disadvantages. When the wheel rotates in regular operation, a relative angular velocity or rotational speed results between the rotating rotor and the statically deflected stator, which is proportional to the speed of the vehicle rolling with the wheel. In the event of a fault, i.e. when the stator overturns, this relative angular velocity is reduced abruptly. In the worst case, the speed of the stator is the same as the speed of the rotor when the wheel is rotating, i.e. the relative angular speed or the differential speed between the stator and the rotor is reduced to zero. There is then no relative movement between the stator and the rotor and no current is generated due to the absence of electromagnetic induction.

When the stator overturns, the power generator can only perform its basic function as a power supplier to a reduced extent or no longer at all. Furthermore, the mechanical stress when the stator overturns can lead to damage to the power generator. In addition, due to its eccentric center of gravity, which causes it to be held statically at a certain angle of rotation during generator operation by gravity, a tumbling stator creates an imbalance that the driver of the vehicle may feel and may be confused by.

In order to prevent the stator from overturning, one could think of designing the stator to be large and heavy so that it can maintain the working position up to a higher speed due to the greater mass and react more slowly and less sensitively to additional accelerations. However, this procedure is disadvantageous because a heavier stator increases the weight of the entire module with the power generator and the stator requires more space, leaving less space for other components such as the rotor or a rechargeable battery. However, the installation space in the wheel hub is generally very limited due to the design of the wheel, and reducing the size of components such as the accumulator or the rotor would have disadvantages. A heavier stator also has the disadvantage that after overturning it takes much longer than a lighter stator to return to the rest or working position because of its greater inertia. Furthermore, it has been shown within the scope of the invention that situations occur during driving operation in which the stator rolls over, no matter how large and heavy it is designed, for example in the case of severe bumps in the roadway like bumps. Overall, increasing the mass of the stator is therefore not a suitable measure to prevent the stator from overturning.

Based on this state of the art, the object of the present invention is to provide an electromagnetic power generator with a rotatably mounted stator with an eccentric center of gravity and a rotor, the power generator being attachable to the wheel of an object that can be moved by means of the wheel and preferably in the cylindrical cavity of the Hub of the wheel can be arranged to create, in which it is ensured by suitable means in practical application that the basic function of the power generator is better guaranteed as a power supplier.

According to the invention, this object is achieved by a power generator having the features of patent claim 1 . Configurations, developments and uses of the invention result from the dependent claims and the following description with associated drawings.

• - Ein erstes Mittel, das zum Erkennen, ob sich der Stator überschlägt, ausgebildet ist, umfassend
• - ein Mittel zum Bestimmen der Drehzahl des Rades und/oder des Rotors,
• - ein Mittel zum Bestimmen der Differenzdrehzahl des Rotors gegenüber dem Stator,
• - ein Mittel zum Vergleichen der bestimmten Drehzahl des Rades und/oder des Rotors und der bestimmten Differenzdrehzahl des Rotors gegenüber dem Stator, und
• - ein Mittel zum Erkennen des Überschlagens des Stators daraus, dass die bestimmte Drehzahl des Rades und/oder des Rotors um mehr als einen insbesondere benutzerdefinierten ersten Schwellenwert von der bestimmten Differenzdrehzahl des Rotors gegenüber dem Stator abweicht,
• - und ein zweites Mittel, das dazu ausgebildet ist, für den Fall, dass von dem ersten Mittel ein Überschlagen des Stators erkannt wird, das Überschlagen des Stators zu beenden, indem der Rotor derart mit Strom beaufschlagt wird, dass der Stator hierdurch beschleunigt wird.

The electromagnetic current generator according to the invention, which has a rotatably mounted stator with an eccentric center of mass and a rotor which can be rotated relative to the stator and which can be mounted on a wheel of an object which can be moved by means of the wheel in such a way that when the wheel is rotated, the rotor moves relative to the stator rotates and as a result the power generator generates power in a generator mode, has the special feature that the power generator includes the following:

• - A first means, which is designed to detect whether the stator is overturning, comprising
• - a means for determining the rotational speed of the wheel and/or the rotor,
• - a means for determining the differential speed of the rotor relative to the stator,
• - a means for comparing the determined speed of the wheel and/or the rotor and the determined differential speed of the rotor with respect to the stator, and
• - a means for detecting the overturning of the stator from the fact that the determined speed of the wheel and/or the rotor deviates by more than a, in particular, user-defined first threshold value from the determined differential speed of the rotor compared to the stator,
• - and a second means, which is designed to end the rollover of the stator in the event that the first means detects a rollover of the stator by applying current to the rotor in such a way that the stator is thereby accelerated.

The invention is described without loss of generality based on the determination of speeds n. Of course, it is possible in an equivalent way to determine a corresponding angular velocity ω instead of one or all of the speeds mentioned, i.e. to measure it or to calculate it from the associated speed n (ω=2πn). The same applies to speeds that can be determined from the speeds and can equivalently be used in place of the latter.

In the context of the invention, it was recognized that it is neither practically possible nor important for real operation to generally prevent the stator from rolling over while the rotating wheel is being driven, as was tried in vain with a very heavy stator, for example, but that the task is thereby is solved in that the overturning of the stator is quickly detected and effectively ended, the rotating stator is thus quasi caught and a permanent rotation of the stator is prevented. This allows the stator to roll over, but prevents the stator from rolling over for a longer period of time while the rotating wheel is in operation. This ensures the basic function of the power generator as a power supplier, which is practically not significantly affected by any occasional or brief overturning of the stator.

The invention is therefore particularly aimed at catching the rotatably mounted stator as quickly as possible in the event of it overturning, whereby it is brought back into the static state of equilibrium of the working position as quickly as possible, even when the object being moved by the wheel is in continuous operation, and the power generator can generate power. To catch the overturning stator, current is applied or driven to the rotor. As a result, the current generator is preferably switched from the generator mode, in which current is generated in the rotor, in particular in the conductor windings of the rotor, to a motor mode in which an electromagnetic rotating field is generated by the rotor, in particular by the conductor windings of the rotor to which current is applied, driven by the overturning stator and by the active intervention by means of the power supply to the rotor back into a particular stationary work position tion is brought, for example, in the original working position before the rollover, so that the power generator can then generate electrical energy again.

Accelerating the overturning stator according to the invention by supplying current to the rotor in order to recapture the overturning stator into a particularly static working position is thus in effect a negative acceleration, i.e. decelerating the overturning rotating stator into a stationary working position. According to the state of the art, such a capture or resetting of the stator has hitherto required the wheel or vehicle not to stand still for too long. With the invention, on the other hand, the overturning of the stator, which is overturning in the event of a fault, can be recognized immediately and reliably and caught during driving operation can take place automatically. The generation of energy by the power generator in particular, as well as the operation of the vehicle in general, are therefore not significantly impaired by a stator that is overturning.

In simplified form, the invention relates to an electromagnetic power generator for a wheel, in particular for a vehicle. The power generator includes a rotatably mounted stator held in an equilibrium position by its eccentric center of mass, and a rotor rotating in the stator and driven by the wheel. In order to catch an overturning, undesirably rotating stator in the event of a fault caused, for example, by shocks, it is proposed to supply current to the rotor.

According to an advantageous development, a means is proposed that is designed so that the rotor is supplied with current in motor mode in such a way that it generates a rotating magnetic field that changes with the determined speed of the wheel and/or the rotor or the determined differential speed of the Rotor rotates relative to the stator. In this case, the rotating magnetic field of the rotor, which acts as the driving motor force on the stator, accelerates the overturning stator until the stator no longer overturns. The specific speed of the wheel and/or the rotor is therefore used to apply an electric rotating field to the power generator in motor mode with this frequency and the resulting mechanical driving force accelerates the overturning, rotating stator until it comes to a standstill relative to the gravitational field. This sequence preferably takes place in a control loop in which the first and the second step are constantly repeated and the frequency with which the rotor is controlled in motor mode for driving the stator is dynamically controlled.

The point in time at which the motor mode is switched back to the generator mode can be determined in various ways. For example, it can be checked whether the stator has reached its target position again. For this purpose, according to a preferred embodiment, a means is proposed which is designed so that the rotor, in particular in motor mode, is supplied with current until the speed of the wheel and/or the rotor deviates by less than a second, in particular, user-defined threshold value from the differential speed of the Rotor differs from the stator. The second threshold can be the same as or different from the first threshold.

In other embodiments, the switch back may be time controlled. For this purpose, a means can be provided which is designed so that current is applied to the rotor, in particular when the current generator is in motor mode, for a predetermined period of time and the current generator is then switched back to generator mode. According to an advantageous development, a means can be provided that is designed to ensure that the specified time duration of the motor mode is selected as a function of the specific speed of the wheel and/or the rotor and/or the speed of the object moved by the wheel and in this case, a predefined or programmed characteristic map is used, in which the predetermined time duration of the motor mode of the current generator is defined as a function of the speed of the wheel or of the rotor or the speed of the object moving with the wheel. In this way, for example, empirical values can be taken into account or the control effort can be simplified.

According to an advantageous feature, a means can be provided which is designed so that after the rotor is supplied with current, in particular the current generator is switched to motor mode, a user-defined pause time is awaited and only after the pause time has elapsed does the current generator switch to the Switched generator mode for generating electricity and the power generator current is taken. During this pause or waiting time, the stator, which has been caught from the overturning and returned to a working position, can settle down and the power generator as a whole can stabilize in this state. During the pause time, the means can be designed so that the rotor is either not charged or charged with a low current, in particular with a lower current than the maximum possible. before The means is preferably designed such that no current is drawn from the current generator, ie from the conductor windings of the rotor, during the pause time. The pause time can be fixed, in particular between 0.1 s and 20 s, preferably between 0.2 s and 10 s and particularly preferably between 0.5 s and 5 s. The pause time can also depend on the speed of the object moved by the wheel or on the speed of the rotor and/or the wheel and can be derived from this, in particular between 0.5 and 1000, preferably between 10 and 500 and particularly preferably between 20 and 100 times the duration of one revolution of the wheel and/or rotor.

In advantageous embodiments, the basic structure of the current generator according to the invention can be designed as a synchronous machine or as an asynchronous machine in order to switch from generator mode to motor mode. A particularly advantageous embodiment is the design as a brushless, electronically commutated direct current motor (brushless DC motor, BL-DC, EC motor). An EC motor is a synchronous motor that can be controlled like a DC motor by means of converter electronics.

The overturning of the stator is detected by the fact that the determined rotational speed of the wheel and/or the rotor deviates by more than the first threshold value from the determined differential rotational speed of the rotor compared to the stator during the overturning. In this case, for example, the determined speed difference between the rotor and the stator is lower than the determined speed of the wheel and/or the rotor by more than the first threshold value, so that the current generator generates current with a frequency that is lower than the speed of the wheel and/or or the rotor (opposite the wheel axle). This is the most common case in practice when the stator overturns, which occurs when the stator, working in generator mode and deflected into the working position, is deflected even further by an additional acceleration, for example due to a shock, and then the one generated by gravity Torque on the stator is no longer sufficient to compensate for the electrical counter-torque of the power generator on the stator and to keep itself in balance. In this case, the stator overturns in the opposite direction to the rotation of the wheel and/or the rotor of the rotor, i.e. the speed of the wheel and/or the rotor is greater than the differential speed of the rotor compared to the stator. If current is then applied to the rotor in such a way that the stator is thereby accelerated, the overturning stator is accelerated in the opposite direction to its direction of rotation in order to bring it into a static working position.

However, it can also happen that the stator, which is working in generator mode and has been deflected into the working position, overturns in the direction opposite to the direction in which it moves from the rest position to the working position due to the additional acceleration, for example due to a shock was deflected. In this case, the stator overturns in the same direction of rotation in which the wheel and/or the rotor rotates, i.e. the speed of the wheel and/or the rotor is less than the speed difference between the rotor and the stator. If current is then applied to the rotor in such a way that the stator is thereby accelerated, the overturning stator is accelerated in the opposite direction to its direction of rotation in order to bring it into a static working position.

In the practical application of the invention, both cases can be taken into account, for example, by using the absolute value of this comparison value when comparing the determined speed of the wheel and/or the rotor or the rotor with the determined speed difference between the rotor and the stator. However, the sign of the comparison value can also be taken into account in order to set the first threshold value with a sign that corresponds to this in the case of a positive or negative comparison value.

In the theoretical ideal case, the first threshold value, when it is exceeded in the first step of the method according to the invention, it is concluded that the stator is overturning and the second step of capturing is initiated by energizing the rotor, is zero, i.e. already when the smallest deviation of the specific speed of the rotor is determined Wheel and/or the rotor from the determined speed difference between the rotor and the stator, it is concluded that the stator is overturning. In practical application, however, a certain tolerance must be allowed. This is based, for example, on tolerances in the measurement accuracy of the methods or sensors used to determine the speeds or on the fact that the stator in the working position makes slight movements around its static equilibrium position or out of it into another equilibrium position, which are caused, for example, by vibrations or load changes and usually do not lead to a rollover.

The same applies to the second threshold below which it is detected that the overturning of the stator is over, after which the rotor is no longer energized to accelerate the stator and the power generator returns from motor mode to generator mode. The second threshold may or may not be the same as the first threshold.

In advantageous embodiments, a means can therefore be provided which is designed so that at least one of the threshold values has a fixed value that differs from zero, in particular between 0.1/s and 20/s, preferably between 0.2/s and 10/s and more preferably between 0.5/s and 5/s.

In other advantageous embodiments, a means can be provided which is designed so that at least one of the threshold values has a non-zero value which depends on the speed of the object moved with the wheel or on the rotational speed of the rotor and/or the wheel and off this is derived, in particular corresponds to a percentage of the speed of the wheel and / or the rotor.

• - Verwendung eines Drehzahlsensors, der die Drehzahl misst,
• - Verwendung eines Beschleunigungssensors, der die Größe der Zentrifugalbeschleunigung oder die Frequenz der Richtungsänderung gegenüber der Schwerkraft misst,
• - Verwendung eines Magnetfeldsensors, der die Frequenz der Richtungsänderung gegenüber dem Erdmagnetfeld oder gegenüber einem Referenzmagneten misst,
• - Verwendung eines induktiven Sensors,
• - Verwendung eines Ultraschallsensors,
• - Verwendung eines optischen Sensors,
• - Verwendung eines exzentrisch ausgerichteten Mikrofons zum Erfassen von Abrollgeräuschen des Rades.

The current generator according to the invention can be mounted on a wheel in such a way that the rotor rotates relative to the stator when the wheel rotates. The rotor is therefore firmly connected to the wheel, for example to the hub of the wheel, so in this case the speed of the rotor is equal to the speed of the wheel or the speed of the rim of the wheel. The speed of the rotor can thus not only be measured directly on the rotor itself, but also determined via the speed of the wheel or rim. In advantageous embodiments, a means can be provided which is designed to determine the speed of the wheel or rotor in at least one of the following ways:

• - Use of a speed sensor that measures the speed,
• - use of an accelerometer that measures the magnitude of centrifugal acceleration or the frequency of change of direction versus gravity,
• - Use of a magnetic field sensor that measures the frequency of the change in direction in relation to the earth's magnetic field or in relation to a reference magnet,
• - use of an inductive sensor,
• - use of an ultrasonic sensor,
• - use of an optical sensor,
• - Use of an off-centre microphone to capture wheel noise.

• - Bestimmung des zeitlichen Abstandes der Nulldurchgänge des von dem Rotor erzeugten Stromes oder mindestens einer Phase des Stromes,
• - Verwendung eines Drehzahlsensors, beispielsweise eines Hallsensors, der die Differenzdrehzahl misst.

In preferred embodiments, a means can be provided which is designed to determine the speed difference between the rotor and the stator in at least one of the following ways:

• - Determination of the time interval between the zero crossings of the current generated by the rotor or at least one phase of the current,
• - Use of a speed sensor, for example a Hall sensor, which measures the differential speed.

The current generated by the conductor windings of the rotor in generator mode has a sinusoidal shape, the frequency of which is given by the speed difference between the rotor and the stator. In a preferred embodiment, the rotor has, for example, three pairs of coils, each of which generates a phase. In order to determine the speed difference between the rotor and the stator, a means can be provided which is designed to determine the zero crossings of the sinusoidal voltage of a phase of the current generator and to record their time interval. The frequency of the phase and thus the speed difference between the rotor and the stator can be determined from the time interval between the zero crossings and the frequency of the zero crossings.

In principle, the invention is suitable for use with any type of wheel with which an object is moved. It does not matter whether it is a wheel that is motor-driven to move the object or that runs passively when the object is moved, i.e. is set in rotation by the moving of the object. There are also generally no restrictions with regard to the moving object. For example, it can be a wheel of an object moving on or along a rail, e.g. a rail vehicle (e.g. locomotive, wagon, roller coaster) or a rail-bound transport device (e.g. an electric monorail), or in particular a road vehicle (e.g. car, motorcycle, bicycle), or a another wheel, e.g. a transport cart. A preferred area of application is use in a motor vehicle wheel, in particular a light-alloy wheel. The object moved by means of the wheel is preferably a vehicle.

A second aspect of the invention, which can be used in combination with or also independently of the above-explained first aspect of the invention of catching a continuous stator, is aimed at reducing the frequency of occurrence of the overturning of the stator by suitable measures gladly. For this purpose, in an electromagnetic power generator, which has a rotatably mounted stator with an eccentric center of mass and a rotor that can be rotated relative to the stator and which can be mounted on a wheel of an object that can be moved by means of the wheel in such a way that when the wheel is rotated, the rotor rotates relative to rotates the stator and the current generator thereby generates current, according to the second aspect of the invention it is proposed in particular that a means is provided which is designed so that the current delivered by the current generator in a generator mode is regulated by means of load control in such a way that it is below a specified limit remains.

In regular operation of the power generator, i.e. in the power-generating generator mode, the stator, as already mentioned, does not rotate or roll over while the rotor rotates together with the wheel, but is merely deflected from its rest position into an almost static working position in which the torque at the stator given by the eccentric center of gravity of the stator corresponds to the torque at the stator given by the current generation of the current generator. The second aspect of the invention is based on the finding that the power generator is less sensitive to influences that trigger a rollover if, in the generator mode of the power generator, the deflection of the stator from its vertical rest position to the working position is less than 90°, preferably less than 60°, in particular between 30 ° to 60°.

The second aspect according to the invention is thus aimed at the activation or regulation of the current generator in normal generator operation in such a way that the stator is deflected by no more than approximately 90° with respect to the vertical. Without load control, the deflection of the stator would increase with increasing speed of the object moved by the wheel, ie with increasing driving speed, and at some point the stator would roll over. However, the current draw is reduced by the load control in such a way that the deflection of the stator is limited even at a high speed of the wheel, without it increasing as the speed of the wheel increases.

• - Einen ersten Schritt zum Bestimmen einer für eine momentane Geschwindigkeit des mit dem Rad bewegten Objektes charakteristischen Drehzahl, aus der abgeleitet werden kann, wie groß die momentan maximal von dem Stromgenerator ohne Lastregelung erzeugbare elektrische Leistung ist,
• - einen zweiten Schritt, in dem geprüft wird, ob die bestimmte charakteristische Drehzahl größer als eine, insbesondere benutzerdefinierte, Einschaltschwelle ist,
• - falls der zweite Schritt positiv beantwortet wird, einen dritten Schritt, in dem dem Stromgenerator eine insbesondere benutzerdefinierte elektrische Last entnommen wird, und einen vierten Schritt, in dem die charakteristische Drehzahl wieder bestimmt wird, sowie einen fünften Schritt, in dem geprüft wird, ob diese charakteristische Drehzahl kleiner als eine insbesondere benutzerdefinierte Ausschaltschwelle ist,
• - falls der fünfte Schritt negativ beantwortet wird, einen sechsten Schritt, in dem die Generatorlast, d.h. der von dem Stromgenerator abgegebene Strom, in Abhängigkeit von der charakteristischen Drehzahl geregelt wird,
• - falls der fünfte Schritt positiv beantwortet wird, einen alternativen sechsten Schritt, in dem die Generatorlast abgeschaltet wird.

In an advantageous embodiment, the load control includes a means that is designed in particular to carry out the following steps:

• - A first step for determining a speed that is characteristic of a current speed of the object moving with the wheel, from which it can be derived how large the current maximum electrical power that can be generated by the current generator without load control is,
• - a second step in which it is checked whether the determined characteristic speed is greater than a switch-on threshold, in particular a user-defined one,
• - if the answer to the second step is affirmative, a third step in which an electrical load, in particular a user-defined one, is taken from the current generator, and a fourth step in which the characteristic speed is determined again, and a fifth step in which it is checked whether this characteristic speed is lower than a, in particular, user-defined switch-off threshold,
• - if the fifth step is answered in the negative, a sixth step in which the generator load, ie the current delivered by the current generator, is controlled as a function of the characteristic speed,
• - if the fifth step is answered in the affirmative, an alternative sixth step in which the generator load is switched off.

This flowchart is preferably executed in a control duration loop, with the control preferably only starting when the electrical load delivered by the current generator exceeds the switch-on threshold and does not fall below the switch-off threshold. The use of the switch-on threshold prevents the load control from interfering even with small electrical loads, and the use of the switch-off threshold prevents the load control from switching on and off alternately with a high frequency. In preferred embodiments, the switch-off threshold is lower than the switch-on threshold.

In an advantageous embodiment, the means can preferably be designed such that the load drawn from the power generator in the third step is adjusted in such a way that it is only a small electrical load. A low electrical load in this sense can preferably be an electrical load that is considerably smaller than the maximum electrical power that can be generated by the power generator, for example 0.5% to 20%, preferably 1% to 10% and particularly preferably 2% to 5% % of the maximum power is, or which is considerably smaller than the electrical power that can be generated in the current operating state of the power generator, for example 0.5% to 20%, preferably 1% to 10% and particularly preferably 2% to 5% of this power.

In a further advantageous embodiment, the means can be designed so that the speed of the wheel and / or as a characteristic speed of the rotor or the speed difference between the rotor and the stator is determined. Since in generator mode the speed of the wheel corresponds approximately to the speed difference between the rotor and the stator when the stator is not overturning, the means can be designed so that the current output by the current generator is, in advantageous embodiments, dependent on the speed of the wheel and/or of the rotor or the speed difference between the rotor and the stator. From both variables it can be derived how large the current maximum electrical power that can be generated by the current generator without load regulation is.

Determining the rotational speed of the wheel and/or the rotor and/or the differential rotational speed of the rotor with respect to the stator can be carried out in the same way, i.e. using the same methods and/or sensors, as in the case of stator capture. In preferred embodiments, the speed of the wheel and/or the rotor and/or the differential speed of the rotor relative to the stator is carried out in exactly the same way as when the stator is caught in the load control, so that no additional structural effort is required for the load control.

In advantageous embodiments, the means can be designed so that in the sixth step, in which the generator load, i.e. the current delivered by the power generator, is controlled by means of the load control, the load control is carried out according to a predetermined characteristic of the power generator and a predefined or programmed one Map is used in which the electrical power of the current generator in generator mode is set depending on the characteristic size or the speed of the moving object with the wheel.

In advantageous embodiments, the power generator has a housing with which it can be mounted on a wheel, the housing preferably being able to be inserted into a cylindrical cavity in the hub of the wheel and/or the housing being adapted to the wheel. The stator is preferably arranged concentrically to the rotor.

A preferred embodiment of the invention is a wheel, in particular for a vehicle, in particular a light metal wheel, with a hub that has a cylindrical cavity, with an electromagnetic current generator according to the invention being arranged in the cylindrical cavity of the hub.

Further advantages and features of the invention result from the claims and the following description, in which exemplary embodiments of the invention are explained in detail with reference to the drawings.

• 1 eine Explosionsdarstellung eines Ausführungsbeispiels eines erfindungsgemäßen Stromgenerators,
• 2 eine perspektivische Ansicht zu 1,
• 3 einen Vollschnitt zu 2 in isometrischer Darstellung,
• 4 den Vollschnitt der 2 in Seitenansicht,
• 5 eine perspektivische Ansicht eines Rades mit dem Stromgenerator gemäß 1f,
• 6 einen radialen Vollschnitt zu 5,
• 7 eine schematische Darstellung der Auslenkung des Stators im Generatormodus des Stromgenerators gemäß 1,
• 8 ein beispielhaftes Ablaufschema einer Steuerung des Stromgenerators beim Wiedereinfangen eines sich überschlagenden Stators,
• 9 ein Diagramm im Generatormodus des Stromgenerators,
• 10 ein beispielhaftes Ablaufschema der Regelung des Stromgenerators mit einer Lastregelung im Generatormodus,
• 11 eine Kennlinie zum Realisieren einer Lastregelung des Stromgenerators und
• 12 ein Blockschaltbild des Stromgenerators.

The special features described therein can be used individually or in combination with one another in order to create preferred embodiments of the invention. Parts that are the same or have the same effect are denoted by the same reference symbols in the various figures and are usually only described once, even if they can be used to advantage in other embodiments. Show it:

• 1 an exploded view of an embodiment of a power generator according to the invention,
• 2 a perspective view 1 ,
• 3 a full cut 2 in isometric view,
• 4 the full cut of 2 in side view,
• 5 a perspective view of a wheel with the power generator according to 1f ,
• 6 a radial full cut 5 ,
• 7 a schematic representation of the deflection of the stator in the generator mode of the current generator according to FIG 1 ,
• 8th an exemplary flow chart of a control of the power generator when recapturing an overturning stator,
• 9 a diagram in generator mode of the power generator,
• 10 an exemplary flow chart of the control of the power generator with a load control in generator mode,
• 11 a characteristic for realizing a load control of the power generator and
• 12 a block diagram of the power generator.

the 1 Fig. 13 illustrates in an exploded view an embodiment of a power generator 1 according to the invention comprising a housing 2 and all the associated components to form a complete module which can be inserted into the cylindrical cavity of a hub 19 of a wheel 17, for example. The structure of the power generator 1 according to 1 largely corresponds to that of the document DE 20 2018 000 629 U1 known power generator 1 and also has the special feature that it comprises a further development of the known power generator 1 means to capture the rotatably mounted stator 3 in the event of its overturning and to regulate the current delivered by the current generator 1 by means of load control.

The core of the power generator 1 is formed by a rotatably mounted stator 3 with an eccentric center of mass and a rotor 4 that can rotate relative to the stator 3 and is arranged concentrically to the stator 3 . The stator 3 consists of ferromagnetic material or is equipped with permanent magnets over its circumference. The stator 3 is arranged to be freely rotatable relative to the rotor 4 by means of a ball bearing 5 and has a radially protruding weight part 6 over a partial circumference, which results in an eccentric center of mass of the stator 3, so that the stator 3 normally does not move with the rotating wheel 17 in which the power generator 1 is mounted, but remains oriented substantially vertically downwards due to gravity. The rotor 4 is equipped with conductor windings, for example in 1 with three pairs of coils. When the conductor windings of the rotor 4 are rotated with the rotor 4 in the stator 3, a voltage is induced in them and the power generator 1 generates power.

The stator 3 and the rotor 4 are arranged in a housing 2 of the power generator 1, which comprises a retaining ring which is mounted on an axially lower, in 1 rear side with a rear housing cover 7 and on an axially upper, in 1 front side is closed with a front cover 8 housing. The rear housing cover 7 carries a central axial bearing axis 9 which rotates in the same way when the housing 2 or the rear housing cover 7 is rotated. The ball bearing 5 for the stator 3 and the rotor 4 are arranged on the bearing axis 9 . The stator 3 can rotate on the bearing axle 9 by means of the ball bearing 5 and thereby remain in a fixed position in space when the housing 2 rotates. In contrast, the rotor 4 is arranged in a non-rotatable manner on the bearing axis 9, so that when the housing 2 rotates, it rotates with the latter.

A coil circuit board 10 with a contact piece 11 is used to electrically contact the coils of the rotor 4, which produces the electrical connection to an electronic circuit board 12, which is arranged on a plate 13, which serves as a base support or an electrical energy storage device that can be recharged by means of the current generator 1. for example, an accumulator (a lithium-ion accumulator or another type) or a capacitor, with which the electrical energy generated by the power generator 1 for powering a consumer is temporarily stored. A decorative cover 14 is attached to the housing front cover 8 and all parts are held together by an axial screw 15 with the associated counterpart 16 .

If the housing 2 is non-rotatably connected to the wheel 17, for example inserted into the cavity of the hub 19 of the wheel 17, the current generator 1 arranged in the housing 2 can generate and provide electric power when the wheel 17 rotates, without a structural change on the wheel 17 is required. When the wheel 17 turns, the rotor 4 turns with the wheel 17 so that when the wheel 17 turns, the rotor 4 turns relative to the stator 3 and the power generator 1 thereby generates power. The stator 3 is stationary deflected from its rest position into a working position and the power generator 1 generates electrical energy that is directly available in the wheel 17 from the rotation of the wheel 17 .

The stator 3 is freely rotatable due to the bearing by the ball bearing 5, which is necessary so that it does not rotate with the rotating wheel 17, but remains in a stationary working position. However, external influences, for example vibrations, can result in the stator 3 overturning, ie being set in undesired rotation. The invention is aimed at catching the rotatably mounted stator 3 in the event of it overturning and, in particular, in a further embodiment, at regulating the current delivered by the power generator 1 by means of load control in order to make the power generator 1 less sensitive to the influences that trigger the overturning. The invention is essentially implemented by functions that are provided by the electronics board 12 . These relate in particular to the capture of the rotatably mounted stator 3 in the event of it overturning or the regulation of the current delivered by the current generator 1 by means of load regulation.

• - Ein Mittel, das zum Erkennen, ob sich der Stator 3 überschlägt, ausgebildet ist,
• - ein Mittel zum Bestimmen der Drehzahl des Rades und/oder des Rotors,
• - ein Mittel zum Bestimmen der Differenzdrehzahl des Rotors 4 gegenüber dem Stator 3,
• - ein Mittel zum Vergleichen der bestimmten Drehzahl des Rades und/oder des Rotors und der bestimmten Differenzdrehzahl des Rotors 4 gegenüber dem Stator 3,
• - ein Mittel, das zum Erkennen des Überschlagens des Stators 3 daraus ausgestaltet ist, dass die bestimmte Drehzahl des Rades und/oder des Rotors um mehr als einen insbesondere benutzerdefinierten ersten Schwellenwert von der bestimmten Differenzdrehzahl des Rotors 4 gegenüber dem Stator 3 abweicht,
• - ein Mittel, das dazu ausgebildet ist, für den Fall, dass von dem ersten Mittel ein Überschlagen des Stators 3 erkannt wird, das Überschlagen des Stators 3 zu beenden, indem der Rotor 4 derart mit Strom beaufschlagt wird, dass der Stator 3 hierdurch beschleunigt wird, beispielsweise während einer vorgegebenen Zeitdauer oder bis die Drehzahl des Rades und/oder des Rotors um weniger als einen insbesondere benutzerdefinierten zweiten Schwellenwert von der Differenzdrehzahl des Rotors 4 gegenüber dem Stator 3 abweicht,
• - ein Mittel, mit dem der Stromgenerator 1 aus dem Generatormodus, in dem in den Leiterwicklungen des Rotors 4 Strom erzeugt wird, in einen Motormodus umgeschaltet wird, in dem von den mit Strom beaufschlagten Leiterwicklungen des Rotors 4 ein elektromagnetisches Drehfeld erzeugt wird, durch das der sich überschlagende, drehende Stator 3 angetrieben und mittels der Stromzuführung zu dem Rotor 4 wieder in eine stationäre Arbeitsstellung gebracht wird, wobei vorzugsweise der Rotor 4 im Motormodus derart mit Strom beaufschlagt wird, dass er ein magnetisches Drehfeld erzeugt, das sich mit der bestimmten Drehzahl des Rades bzw. des Rotors oder der bestimmten Differenzdrehzahl des Rotors 4 gegenüber dem Stator 1 dreht,
• - ein Mittel zum Bestimmen einer für eine momentane Geschwindigkeit des mit dem Rad bewegten Objektes charakteristischen Drehzahl, aus der abgeleitet werden kann, wie groß die momentan maximal von dem Stromgenerator 1 ohne Lastregelung erzeugbare elektrische Leistung ist,
• - ein Mittel zum Prüfen, ob die bestimmte charakteristische Drehzahl größer als eine insbesondere benutzerdefinierte Einschaltschwelle ist,
• - ein Mittel zum Entnehmen einer elektrischen Last aus dem Stromgenerator 1,
• - ein Mittel zum Prüfen, ob die bestimmte charakteristische Drehzahl kleiner als eine, insbesondere benutzerdefinierte, Ausschaltschwelle ist,
• - ein Mittel zum Regeln des von dem Stromgenerator 1 abgegebenen Stromes in Abhängigkeit von der charakteristischen Drehzahl,
• - ein Mittel zum Abschalten der Generatorlast,
• - ein Mittel zum Stabilisieren oder Regeln der von dem Stromgenerator 1 erzeugten elektrischen Spannung,
• - ein Mittel zum Speichern der von dem Stromgenerator erzeugten elektrischen Energie,
• - ein Mittel zum Ansteuern des Stromgenerators 1 im Generatormodus und
• - ein Mittel zum Ansteuern des Stromgenerators 1 im Motormodus.

The electronic circuit board 12 or other components of the power generator 1 can in particular include one or more of the following components:

• - A means designed to detect whether the stator 3 rolls over,
• - a means for determining the rotational speed of the wheel and/or the rotor,
• - a means for determining the differential speed of the rotor 4 compared to the stator 3,
• - a means for comparing the determined speed of the wheel and/or the rotor and the determined differential speed of the rotor 4 with respect to the stator 3,
• - A means that is designed to detect the overturning of the stator 3 from the fact that the specific speed of the wheel and / or the rotor by more than a particular user-defined first threshold value of the determined speed difference between the rotor 4 and the stator 3 differs,
• - a means which is designed to stop the rollover of the stator 3 in the event that the first means detects a rollover of the stator 3 by applying current to the rotor 4 in such a way that the stator 3 thereby accelerates is, for example during a predetermined period of time or until the speed of the wheel and/or the rotor deviates by less than a second threshold value, which is in particular user-defined, from the speed difference between the rotor 4 and the stator 3,
• - a means by which the current generator 1 is switched from the generator mode, in which current is generated in the conductor windings of the rotor 4, to a motor mode, in which a rotating electromagnetic field is generated from the conductor windings of the rotor 4 to which current is applied, through which the overturning, rotating stator 3 is driven and brought back into a stationary working position by means of the power supply to the rotor 4, with the rotor 4 preferably being supplied with current in motor mode in such a way that it generates a rotating magnetic field that moves at the specific speed of the wheel or the rotor or the determined differential speed of the rotor 4 rotates in relation to the stator 1,
• - a means for determining a speed that is characteristic of a current speed of the object moving with the wheel, from which it can be derived how large the current maximum electrical power that can be generated by the current generator 1 without load control is,
• - a means for checking whether the determined characteristic speed is greater than a particular user-defined switch-on threshold,
• - a means for extracting an electrical load from the power generator 1,
• - a means for checking whether the determined characteristic speed is less than a, in particular user-defined, switch-off threshold,
• - a means for controlling the current delivered by the current generator 1 as a function of the characteristic speed,
• - a means of shutting down the generator load,
• - a means for stabilizing or regulating the electrical voltage generated by the power generator 1,
• - a means for storing the electrical energy generated by the power generator,
• - a means for driving the current generator 1 in generator mode and
• - a means for driving the power generator 1 in motor mode.

the 2 shows a perspective view of the power generator 1 of FIG 1 , the 3 a full cut 2 in isometric representation and the 4 a full cut 2 in side view.

the 5 shows a perspective view of the wheel 17 with a power generator 1 according to the invention. The wheel 17 shown by way of example is a conventional alloy wheel of a motor vehicle with a rim 18 onto which a tire (not shown) can be fitted. The wheel 17 comprises a radially centered hub 19 , the rim 18 coaxial thereto and a radial part extending between the rim 18 and the hub 19 . The radial part can, for example, be a wheel disc, also with interruptions, or consist of several wheel spokes 20 distributed over the circumference of the wheel, which extend radially from the hub 19 to the rim 18, for example five or seven wheel spokes 20, which are preferably evenly spaced in the circumferential direction are distributed.

The hub 19 is designed as a hollow cylinder. When the wheel 17 is mounted on the axle of a vehicle, the vehicle shaft protrudes into the cavity of the hub 19, the wheel 17 being connected to a fastening disc firmly connected to the axle of the vehicle by means of connecting screws inserted through openings surrounding the hub 19, so that when the shaft of the vehicle is rotated, the wheel 17 is also set in rotation or, in the case of a non-driven wheel 17, the wheel 17 can rotate on the axle when the vehicle is moving.

The power generator 1 has according to 5 a housing 2 with which it is mounted on the wheel 17, the housing 2 being inserted in a cylindrical cavity of the hub 19 of the wheel 17 and fitted to the wheel 17. The adaptation of the housing 2 to the wheel 17 can concern the design and/or the construction or the dimensions of the wheel 17, the hub 19 or the cavity. The power generator 1 forms an autonomous unit or a module, ie one that is independent of an external energy supply, and is suitable for use on many different rims 18 or wheels 17 .

The power generator 1 can also be used with any direction of rotation of the wheel 17 be formed, for example, for the wheels 17 of a vehicle both on the left and on the right side of the vehicle. Provision can be made for the direction of rotation of the wheel 17 to be automatically detected and evaluated by means of the electronic circuit board 12 or a sensor, in particular when the object being moved with it is traveling forwards. For example, it can be provided that the power generator 1 is designed for use in two different directions of rotation and thus for use on the left and right side of the vehicle. In a preferred embodiment, four-quadrant operation can be implemented that takes into account the parameters generator mode, motor mode, counterclockwise rotation and clockwise rotation and in which the direction of rotation is thus automatically recognized.

In the case of the example in 5 wheel 17 shown, the electromagnetic power generator 1 is arranged in the cylindrical cavity of the hub 19. As already mentioned, it includes the decorative cover 14, which serves as a hub cap, occupies a small part of the outer height of the cavity and with which it is inserted in the axially outer region of the cavity in the center of the hub 19 in a rotationally fixed manner. When the wheel 17 rotates, the decorative cover 14, the housing 2 with the front cover 8 and the rear cover 7, the electronic circuit board 12, the plate 13, the coil circuit board 10 and the rotor 4 with the conductor windings or Pairs of coils, while the stator 3, which is freely rotatable relative to the rotor 4, remains in a fixed static position relative to the orientation of the gravitational force due to its eccentrically arranged center of gravity due to the weight part 6.

By turning the rotor 4 in the stator 3 when the wheel 17 turns, electric current is generated in the rotor 4, which can be controlled via the electronic circuit board 12 in the wheel 17 and supplied to an electrical consumer or a rechargeable electrical energy store. In this way, electrical energy can be made available on or in the wheel 17, which turns on a vehicle, without the need to change the wheel 17 and without great effort, which energy is obtained solely from the turning of the wheel 17. The power generator 1 thus represents an energy harvester, i.e. a component that harnesses energy that is available in the environment in which the component is used.

the 6 shows a full radial section of the in 5 shown wheel 17 with power generator 1.

the 7 shows a schematic representation of the deflection of the stator 3 in the generator mode of the power generator 1, ie when generating power in a rotating wheel 17. If the object moving with the wheel 17 moves at the speed v, the wheel 17 rotates with the associated Speed n.Rad or the angular velocity ω.Rad. The rotor 4 of the current generator 1 with the coil pairs also rotates at the same speed n.Rotor = n.Rad. The stator 3 has an eccentric center of mass 21 and is freely rotatably mounted. When the stator 3 is rotated, the deflection angle β of its center of mass 21 changes 7 illustrated as swinging pendulum 22.

mit

• M.Stator = Gegendrehmoment des Stators
• M.Gen = Drehmoment des Generators

In the rest position, i.e. when the wheel 17 and the rotor 4 are stationary and the power generator 1 is not generating any electricity, the rotatably mounted stator 3, designed as a pendulum 22, is rotated downwards by gravity into a vertical rest position due to its eccentric center of mass 21 and held there. The deflection angle β is then 0°. In the generator mode, ie when the wheel 17 and the rotor 4 rotate, the power generator 1 generates electrical current or electrical power. The rotor 4 causes a corresponding torque M.Gen of the power generator 1 on the stator 3, through which the stator 3 is rotated from the rest position by the deflection angle β into a working position until the torque M.Stator caused by the weight force of the Stators 3 corresponds to the torque M.Gen of the power generator 1 caused by the induction, that is, the force of gravity acting on the stator 3 or pendulum 22 provides the counter-torque to the torque M.Gen of the power generator 1 . So in the working position $$\text{M}\text{.Stator}=\text{M}\text{.Gene}$$

With

• M.Stator = counter torque of the stator
• M.Gen = Torque of the generator

mit

• r = Abstand des exzentrischen Massenschwerpunkts des Stators von seiner Drehachse
• m.Stator = Masse des Stators (des Pendels)
• g = Erdbeschleunigung
• β = Auslenkungswinkel des Stators aus der Ruhestellung
• U = elektrische Spannung des Stromgenerators
• I = elektrischer Strom des Stromgenerators
• ω.Rad = Winkelgeschwindigkeit des Rades bzw. des Rotors

It follows from this equation that the deflection angle β of the stator 3 is set in equilibrium in such a way that the following relationship applies: $$\text{right}\times \text{m}\text{.Stator}\times \text{G}\times \text{sin}\mathrm{\beta =}\left(\text{u}\times \text{I}\right)/\mathrm{\omega }\mathrm{.}\text{wheel}$$

With

• r = distance of the eccentric center of mass of the stator from its axis of rotation
• m.Stator = mass of the stator (of the pendulum)
• g = acceleration due to gravity
• β = deflection angle of the stator from the rest position
• U = electrical voltage of the power generator
• I = electric current of the power generator
• ω.Rad = angular velocity of the wheel or rotor

In regular operation, the deflection of the stator 3 from the rest position is almost static or constant and is determined by the torque M.Gen of the current generator 1 caused by the induction. However, disturbances occurring during driving operation can result in the stator 3 being deflected from the working position in such a way that it rolls over, ie begins to rotate unintentionally and in an uncontrolled manner. As a result of the stator 3 being caught according to the invention, the occurrence of this flashover in the event of a fault is detected and the flashover is ended.

the 8th shows an exemplary flowchart of a method for operating the power generator 1 when recapturing the overturning stator 3. After the initialization 23 of the controller, the speed n.Rad of the wheel 17 and/or the rotor 4 relative to the fixed wheel axle is determined in a first step S1 . This is done with a means S1.M for determining the system status in the generator mode, for example by reading out and evaluating data from a speed or acceleration sensor installed for this purpose, or from an alternative component.

In the next step, a query A1 is used to check whether the wheel 17 is rotating, i.e. whether the speed n.Rad of the wheel 17 or the corresponding speed n.Rotor of the rotor 4 is greater than zero. If the answer is yes, the speed difference n.Diff of the rotor 4 in relation to the stator 3 is determined in the subsequent step S2. This is done with a means S2.M for determining the system status in generator mode, for example by determining the time interval between the zero crossings of the sinusoidal voltage of a current phase of rotor 4, from which differential speed n.Diff can be determined. Alternatively, signals from a Hall sensor installed in the wheel 17 can also be used.

In the next step, in a query A2, the specific speed n.Rad of the wheel 17 and/or the specific speed n.Rotor of the rotor 4 is compared with the specific speed difference n.Diff of the rotor 4 compared to the stator 3 and it is checked whether both values match or differ by more than a first threshold. In particular, the first threshold value can be defined in a user-defined manner. If the two values are the same within the tolerance specified by the first threshold value, there is no fault and the stator 3 has not rolled over. The current generator 1 then remains in generator mode GM. In this, a generator load GL can be supplied with electricity by the electricity generator 1 and, optionally, load regulation GLR of the electricity generator 1, which is explained further below, can be carried out. The method for detecting and ending the overturning of the stator 3 is continuously repeated in a loop, which is illustrated in the flow chart by a return to the first step S1.

If, on the other hand, it is determined in query A2 that the two values deviate from one another by more than the tolerance specified by the first threshold value, i.e. for example if the differential speed n.Diff of the rotor 4 compared to the stator 3 is less than the speed of the wheel 17 and/or or the rotor 4, it is concluded that there is a fault and the stator 3 is overturning, and the steps of stopping the overturning of the stator 3 and recapturing the stator 3 are initiated. To end the overturning of the stator 3, the current generator 1 is then switched over from the generator mode GM to the motor mode in the switching step S3, for which purpose the means S3.M initially switch off the generator load GL. In the following acceleration step S4, the rotor 4 is energized in such a way that the stator 3 is thereby accelerated. This is preferably done in such a way that the rotor 4 is supplied with current in such a way that it generates a rotating magnetic field that changes with the specific speed n.Rad of the wheel 17 and/or the rotor 4 or the specific differential speed n.Diff of the rotor 4 relative to the stator 3 rotates. The rotor 4 is energized until the position of the stator 3 is stationary again, i.e. it no longer rotates relative to the wheel axle but stands still relative to the wheel axle, and thus the relative speed n.Diff between the stator 3 and rotor 4 again the speed n.Rad of the wheel 17 and/or the rotor 4 is consistent. The means S4.M in the acceleration step S4 is therefore used to increase the speed of the stator 3 via the predefined characteristic of the current generator 1.

Following the acceleration step S4, a waiting step S5 is carried out, in which the current generator 1 is not supplied with current during a waiting time of, for example, 5 s so that the stator 3 can settle down. Switching off the current supply to the current generator 1 in the motor mode serves as the associated means S5.M. As an alternative or in addition to the waiting step S5, a query can also be carried out as to whether the speed of the wheel 17 and/or the rotor 4 deviates by less than a second threshold value from the determined speed difference n.Diff of the rotor 4 in relation to the stator 3. The second threshold may also be user-definable and the first and second thresholds may be the same or different. After the stator 3 has been successfully recaptured, automatic switching from the motor mode to the generator mode GM takes place in switching step S6, and the regular, error-free operation of the power generator 1 is continued. In this case, too, the individual steps are repeated, ie the flowchart continues to run through in loops.

This in 9 in addition to the 7 The diagram shown represents the torque M.Gen of the current generator 1 occurring between the rotor 4 and the stator 3 during generator operation GM and the corresponding position of the stator 3, i.e. the deflection angle β of the stator 3 from the rest position, each as a function of the speed v des Vehicle qualitatively. The solid horizontal line in the diagram shows the maximum permissible torque M.Gen.max of the power generator 1. The dashed line shows the torque M.Gen.o of the power generator 1 as it would result without intervention, control or regulation . The double line shows the deflection angle β.o of the stator 3 as it would occur without intervention, open-loop or closed-loop control. When the limit speed v.max is reached, the deflection angle is β=90°, ie the pendulum 22 is in the horizontal position. In this position, the counter-torque M.Stator of the stator 3 reaches its maximum and becomes smaller again as the deflection angle β continues to increase. Without further control, an increase in the vehicle speed v above the limit speed v.max would therefore result in the stator 3 overturning, with the stator 3 starting to rotate about its axis of rotation in an uncontrolled manner.

As a result, from a certain speed v of the vehicle or the corresponding speed n.Rad of the wheel 17, the electrical power output by the power generator 1, i.e. the current of the power generator 1, should no longer increase so that the stator 3 is not deflected so far that it can no longer provide the required counter-torque. The triple line shows the profile of the torque M.Gen.m of the current generator 1, which is controlled accordingly by means of a load control, for the limit case in which the limit value of 90° is assumed for the maximum permissible deflection angle β. The load control is preferably carried out in such a way that when the wheel 17 is in motion, the maximum deflection of the stator 3 by the deflection angle β from its vertical rest position to the working position is a maximum of 90°.

the 10 shows an exemplary flow chart of the load control of the power generator 1, which is used to limit the frequency of overturning of the stator 3.

After the initialization 23 of the controller, in a first step T1, a rotational speed characteristic of the instantaneous speed v of the object moving with the wheel 17 is determined, from which it can be derived how large the instantaneous maximum electrical power that can be generated by the current generator 1 without load control is . This specific characteristic speed can in particular be the speed n.Rad of the wheel and/or the rotor 4 relative to the stationary wheel axle or the differential speed n.Diff of the rotor 4 in relation to the stator 3 . The determination is made with a means T1.M for determining the system status, for example by determining the time interval between the zero crossings of the sinusoidal voltage of a phase of the rotor 4, from which the differential speed n.Diff can be determined. Alternatively, the use of signals from a Hall sensor installed in the wheel 17 can also be considered.

In the next step, a query B1 checks whether the determined characteristic speed is greater than a user-defined switch-on threshold. If the answer is yes, an electrical load is taken from the power generator 1 in the subsequent step T2. This load is preferably low, i.e. significantly smaller than the maximum electrical power that can be generated by the power generator than the electrical power that can be generated in the current operating state of the power generator. A current generator load control, which sets a minimum current draw, serves as a means T2.M for this purpose. In the subsequent step T3, the characteristic speed is determined again. The determination is made with a means T3.M for determining the load control system status, for example by determining the time interval between the zero crossings of the sinusoidal voltage of a phase of the rotor 4. In the subsequent query B2, it is then checked whether this characteristic speed is lower than a turn-off threshold.

If the answer to query B2 is yes, the generator load is switched off in a step T4 and the method returns to step T1. If, on the other hand, the answer to query B2 is no, in a step T5 the generator load, ie the current delivered by the current generator 1, is regulated as a function of the characteristic speed. The load regulation thus takes place in accordance with the predefined characteristics of the current generator 1 in the generator mode. A power generator load control is used as a means T5.M for this purpose, preferably using a predefined or programmed characteristic diagram with the characteristics of the power generator 1. By means of the load control, in Genera Tormodus the current of the power generator 1 and thus the torque of the power generator 1 are regulated. The method then returns to step T3 in a control loop.

An impermissibly high generator torque between the rotor 4 and the stator 3 can thus be avoided by means of the load control, which would lead to a rollover of the stator 3 without load control, as shown in FIG 9 was explained. The load regulation takes place in such a way that the deflection angle of the stator 3 is limited to a limit value of less than 90° in the generator mode. From a certain speed v of the vehicle or from the corresponding speed of the wheel 17 or the rotor 3, the load control limits the electrical power of the current generator 1 in order to limit the maximum deflection of the stator 3 in generator mode.

It was found within the scope of the invention that the load control preferably takes place in such a way that when the wheel 17 is in motion, the maximum deflection of the stator 3 by the deflection angle β from its vertical rest position to the working position is a maximum of 90°. The power generator 1 is then less sensitive to influences that trigger overturning, without the torque between the rotor 4 and the stator 3 and thus the electrical power generated by the power generator 1 being restricted too severely by the load control.

The load control of the power generator 1 described can also be used without the method for recapturing a stator 3 that has overturned. However, in preferred embodiments, the load regulation is used in combination with the recapture of the stator 3 in the event of its overturning. This is because the load regulation basically limits the electrical power generated by the power generator 1 . In order to achieve the highest possible energy yield, this power limitation should be as small as possible. If the load control is performed without the flashover detection and termination method, the electric power of the power generator 1 must be restricted to a large extent in order to prevent the stator 3 from flashover as much as possible. On the other hand, when the load control is used in combination with the rollover detecting and stopping method, the electric power of the power generator 1 needs to be restricted to a much lesser extent. In this case, an occasional overturning of the stator 3 can be accepted since the overturning does not continue, but the stator 3 is immediately caught again. With a combination of load regulation with recapture, the current generator 1 can thus work in an optimized range in which a higher energy yield is achieved than with sole load regulation.

the 11 shows as an exemplary embodiment of a map that is used in the in 10 illustrated load regulation is used, a characteristic curve 24 used for realizing the load regulation of the current generator 1 in the generator mode, which is programmed or stored. The diagram qualitatively shows the controlled electrical output power P of the power generator 1 as a function of the vehicle speed v. The charging current for an electrical energy store, for example an accumulator, is set proportionally to the output power P of the current generator 1 by means of a charge controller for the linear range of the curve of the characteristics map. The power consumed by the charge controller corresponds to the output power of the generator P. The voltage at the charge controller is kept constant throughout the vehicle's speed range, while the output voltage of the current generator increases with increasing vehicle speed v. As a result, different values result for the current of the current generator 1 and the charging current delivered by the charge controller.

the 12 shows a block diagram-like basic representation of the electrical, electronic or electrotechnical structure of the overall system in a power generator 1. It shows the energy flow and the data flow between the individual subsystems and components. The core and node is a controller 30 in which all system data are brought together and processed and which controls the system components. It preferably includes a microprocessor or microcontroller 31. The controller 30 receives data from the determination 32 of the speed of the wheel 17 and/or the rotor 4, for example from an acceleration sensor 33, and from the determination 34 of the speed difference between the rotor 4 and the stator 3, for example by evaluating 35 zero crossings of a current phase of the generator voltage. With this data, the recovery of the overturning stator 3 or the load control can be performed. The motor control 36 of the power generator 1, for example an EC motor driver 37, can be used to control the rotor 4 of the power generator 1. The output-side voltage stabilizer 38 of the power generator 1 serves to rectify and stabilize the preferably three-phase output voltage of the power generator 1. It includes, for example, a B6 rectifier 39 and a step-up/step-down converter 40.

The controller 30 uses the power generator control 36 (eg an EC motor driver 37) to drive the rotor 4 or the power generator 1 by motor and influence the charging current of an energy storage device 41 . The energy storage 41 includes, for example, a battery management system 42 and an electrical energy store 43, such as a lithium-ion battery. An electrical load 44 supplied with power by the power generator 1, for example LED lighting 45, is connected to the energy storage device 41.

All of the components shown or a selection thereof can be arranged on a common electronic circuit board.

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• DE 202018000319 U1 [0008]
• US 2014/0043839 A1 [0008]
• DE 202018000629 U1 [0009, 0055]

Claims (18)

Electromagnetic current generator (1), which has a rotatably mounted stator (3) with an eccentric center of mass (21) and a rotor (4) which can be rotated relative to the stator (3), and which is mounted on a wheel (17) in this way by means of the wheel (17) movable object can be mounted, that when the wheel (17) turns, the rotor (4) rotates relative to the stator (3) and the power generator (1) thereby generates power in a generator mode, characterized in that the power generator ( 1) comprises: - a first means adapted to detect whether the stator (3) is overturning, comprising - means for determining the rotational speed of the wheel (17) and/or the rotor (4), - a Means for determining the differential speed of the rotor (4) compared to the stator (3), - a means for comparing the determined speed of the wheel (17) and/or the rotor (4) and the determined differential speed of the rotor (4) compared to the stator (3), and - a means of recognizing the over striking the stator (3) because the determined speed of the wheel (17) and/or the rotor (4) deviates by more than a, in particular, user-defined first threshold value from the determined differential speed of the rotor (4) compared to the stator (3), - and a second means which is designed to end the flashing of the stator (3) in the event that the first means detects a flashover of the stator (3) by applying current to the rotor (4) in this way is that the stator (3) is thereby accelerated. power generator after claim 1 , characterized by a means which is designed to switch the current generator (1) from the generator mode, in which current is generated in the rotor (4), in particular in conductor windings of the rotor (4), to a motor mode in which a rotating electromagnetic field is generated by the rotor (4), in particular by the conductor windings of the rotor (4) to which current is applied, by means of which the overturning stator (3) is driven and, by means of the power supply to the rotor (4), again in a particularly stationary position working position is brought. power generator after claim 2 , characterized by a means which is designed to apply current to the rotor (4) in motor mode in such a way that it generates a rotary magnetic field which changes with the specific speed of the wheel (17) and/or the rotor (4 ) or the specific speed difference between the rotor (4) and the stator (3) rotates. Current generator according to one of the preceding claims, characterized by a means which is designed so that the rotor (4), in particular in motor mode, is supplied with current until the speed of the wheel (17) and/or the rotor (4) is less than a particular user-defined second threshold value of the differential speed of the rotor (4) compared to the stator (3). Power generator according to one of Claims 1 until 3 , characterized by a means which is designed so that the rotor (4), in particular in the motor mode, is supplied with current for a predetermined period of time and the current generator (1) is then switched back to the generator mode. power generator after claim 5 , characterized by a means which is designed so that the predetermined time duration of the motor mode depending on the determined speed of the wheel (17) and / or the rotor (4) and / or the speed (v) of the wheel ( 17) moving object is selected and a predefined or programmed characteristic map is used in which the specified time duration of the motor mode depending on the speed of the wheel (17) and/or the rotor (4) and/or the speed (v) of the wheel (17) moving object is fixed. Power generator according to one of the preceding claims, characterized by a means which is designed so that after the rotor (4) is supplied with current, in particular the power generator (1) is switched to the motor mode, a user-defined pause time is awaited and only after the elapse of the pause time, the power generator (1) is switched to generator mode and power is drawn from the power generator (1). Current generator according to one of the preceding claims, characterized by a means which is designed so that at least one of the threshold values has a fixed predetermined value deviating from zero, in particular between 0.1/s and 20/s, preferably between 0.2/s s and 10/s and more preferably between 0.5/s and 5/s. Current generator according to one of the preceding claims, characterized by a means which is designed to ensure that at least one of the threshold values has a non-zero value which depends on the speed (v) of the object moved by the wheel (17) and/or on the Speed of the rotor (4) and / or wheel (17) depends and is derived from this. Power generator according to one of the preceding claims, characterized by a means designed to determine the speed of the wheel (17) and/or the rotor (4) in at least one of the following ways: - Use of a speed sensor that detects the speed - using an accelerometer, which measures the magnitude of centrifugal acceleration or the frequency of change of direction with respect to gravity, - using a magnetic field sensor, which measures the frequency of change of direction with respect to the earth's magnetic field or with respect to a reference magnet, - using an inductive sensor, - using a Ultrasonic sensor, - use of an optical sensor, - use of an eccentrically aligned microphone for detecting rolling noise of the wheel (17). Current generator according to one of the preceding claims, characterized by a means which is designed to determine the differential speed of the rotor (4) relative to the stator (3) in at least one of the following ways: - Determination of the time interval between the zero crossings of the Rotor (4) generated current or at least one phase of the current, - Use of a speed sensor, such as a Hall sensor, which measures the differential speed. Current generator according to one of the preceding claims, characterized by a means which is designed to regulate the current delivered by the current generator (1) by means of load regulation in such a way that it remains below a predetermined limit value. power generator after claim 12 , characterized by means that are designed to specify the limit value in such a way that, in the generator mode of the current generator (1), the deflection of the stator (3) from its vertical rest position into the working position is less than 90°, in particular less than 60° amounts to. power generator after claim 12 or 13 , characterized by a means that is designed to carry out the following steps: - A first step for determining a for a momentary speed (v) of the wheel (17) moving object characteristic rotational speed, from which it can be derived how large the is currently the maximum electrical power that can be generated by the power generator (1) without load control, - a second step in which it is checked whether the determined characteristic speed is greater than a particularly user-defined switch-on threshold, - if the answer to the second step is positive, a third step , in which an electrical load is taken from the power generator (1), and a fourth step, in which the characteristic speed is determined again, and a fifth step, in which it is checked whether this characteristic speed is lower than a particularly user-defined switch-off threshold, - if the fifth step is answered negatively, a s next step, in which the generator load, ie the current output by the current generator (1), is controlled as a function of the characteristic speed, - if the fifth step is answered positively, an alternative sixth step, in which the generator load is switched off. power generator after Claim 14 , characterized by means which are designed to determine the speed of the wheel (17) and/or the rotor (4) or the speed difference between the rotor (4) and the stator (1) as the characteristic speed. Power generator according to one of Claims 14 or 15 , characterized by a means which is designed so that in the sixth step, in which the generator load, ie the current supplied by the power generator (1), is controlled by means of the load control, the load control is carried out according to a predetermined characteristic of the power generator (1) carried out and a predefined or programmed characteristic map is used, in which the electrical power of the current generator (1) in the generator mode is defined as a function of the characteristic variable or the speed (v) of the wheel (17) moving object. Power generator (1) according to any one of the preceding claims, characterized in that the power generator (1) has a housing (6) with which it can be mounted on a wheel (17), the housing (6) preferably in a cylindrical cavity of the Hub (19) of the wheel (17) can be used and/or the housing (6) is adapted to the wheel (17). Wheel (17), in particular for a vehicle, in particular a light metal wheel, with a hub (19) which has a cylindrical cavity, characterized in that in the cylindrical cavity of the hub (19) an electromagnetic current generator (1) is arranged according to one of the preceding claims.

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