DE102010020125B4 - Arrangement for contactless energy transfer - Google Patents

Abstract

Arrangement for contactless power transmission from a ground-laid primary conductor to a vehicle, the vehicle having a secondary winding on its surface area facing the ground, which can be inductively coupled to the primary conductor, in particular by approaching a vehicle position by means of the vehicle, with a sensor in one surrounded by protective means Space area is arranged between the secondary winding and the primary conductor, which can be monitored by the sensor, with a protective means being extendable so that the minimum distance between protective means and floor can be reduced, or can be retracted so that the minimum distance between protective means and floor is increased, with means of an actuator, a force can be applied to the protective means that exceeds a spring force generated by a spring element, - so that when the actuator is switched off, the protective means is extended by means of the spring force and - so that the protective means can be retracted when the actuator is switched on.

Description

The invention relates to an arrangement for contactless energy transmission.

From the DE 103 38 852 A1 a system for contactless energy transfer is known.

From the postpublished DE 10 2009 033 236 A1 a device for inductive energy transmission is known.

From the JP 2008 - 054 424 A there is known a power transmission device for a vehicle.

A wireless energy transmission system is known from US 2010/0109445 A1.

A device for contactless energy transmission is known from US 2009/015210 A1.

A bidirectional energy and data transmission with security detection is known from US 2009/0 195 237 A1.

A battery charger is known from US 2009/0153 098 A1.

From the DE 10 2007 033 654 A1 a charging station for an electric vehicle is known, a trough being provided for positioning the vehicle in the optimal position for inductive charging.

From JP H05- 336 605 A1 a system for contactless energy transmission is known, the transmission head having an E-shaped core and a forward conductor and a return conductor of the elongated primary conductor system being arranged in parallel.

From the JP 2010 - 098 807 A a system for contactless energy transfer is known.

A contactless energy transmission system is known from US 2009/0278 523 A1.

The invention is therefore based on the object of developing the safety in a device for contactless energy transmission.

According to the invention, the object is achieved with the arrangement for contactless energy transmission according to the features specified in claim 1.

Important features of the invention in the arrangement for contactless energy transmission are that it is intended for energy transmission from a primary conductor laid on the ground to a vehicle,
wherein a sensor is provided with which at least the space between the secondary winding and the primary conductor can be monitored.

The advantage here is that the room area is monitored, in particular for dangers such as the intrusion of objects into the room area, dangerous heating or the like. Thus, the security is increased. The monitoring can be carried out by a sensor that is separate from the windings or uses existing parts, such as windings. In the first-mentioned case, an independent function can be guaranteed and in the last-mentioned case, a compact, inexpensive design can be achieved.

In an advantageous embodiment, the sensor is a smoke alarm. The advantage here is that a critical condition can be detected when smoke is generated. The smoke detector is advantageously integrated with the coil comprising the secondary winding or primary winding.

In an advantageous embodiment, the sensor is an ultrasonic sensor. The advantage here is that the penetration of an object, in particular also a non-metallic object, can be detected. The calibration of the sensor can be carried out after moving to the position for the inductive transfer of energy.

In an advantageous embodiment, the sensor has a receiving coil which makes signals from a transmitting coil receivable. The advantage here is that the received signal is dependent on the material present in the transmission range. The intrusion of objects can in particular also be detected from the change in the received signal after the calibration.

In an advantageous embodiment, the primary conductor or the secondary winding is used as the transmission coil. The advantage here is that no additional transmitter coil is necessary, but rather the winding that is available for the energy transmission can be used.

In an advantageous embodiment, the primary conductor or the secondary winding is used as the receiving coil. The advantage here is that again no additional transmitter coil is necessary, but rather the winding available for the energy transmission can be used.

In an advantageous embodiment, means for generating pulse-shaped current components are provided, which are connected to the transmission coil, in particular the pulse-shaped Current components are modulated onto the current of the primary conductor or the secondary winding. The advantage here is that the response can be detected with a good signal-to-noise ratio after the pulse has decayed. In particular, the decay of the response pulse is determined and characterized by the decay of eddy currents in the objects present in the spatial area. In this way, values of physical state variables of the object can also be determined.

In an advantageous embodiment, a means for generating current components, in particular periodic current components, is provided, which are connected to the transmitter coil and have a higher frequency than the frequency of the alternating current impressed in the primary conductor, in particular these current components being applied to the current of the primary conductor or the secondary winding are modulated. The advantage here is that a method for determining the inductance can be used and thus a high level of measurement accuracy can be achieved.

In an advantageous embodiment, the protective means is made of such a material that the sensitive area of the sensor is restricted to the spatial area delimited by the protective means,
in particular where the material is impermeable or reflective for the material detectable by the sensor, such as gas or smoke, and / or radiation fields, such as magnetic fields, ultrasound, visible light, and / or infrared,
in particular wherein the sensor is arranged in the spatial area surrounded by the protective means. The advantage here is that the matter or the radiation field is concentrated in the spatial area and thus the detection can be carried out with a better signal-to-noise ratio. For example, the protective means are designed with a metallic coating. Interfering infrared sources located in the vicinity are thus better shielded and a heated infrared source located within the protective means, i.e. in the room area, for example a metallic object heated by eddy currents, also increases the smoke concentration for a smoke sensor and also enables improved detection, especially in the case of in the surrounding wind. In the case of detection of magnetic fields, protective means which are equipped with a magnetically shielding material, such as metal, reduce the stray field and thus the sensitive area is also limited to the spatial area delimited by the protective means.

In an advantageous embodiment, the output signals of the sensor are fed to a control unit which is connected to means for triggering an action, in particular the action displaying warning information, forwarding warning information via fieldbus, switching off means for energy transmission and / or reducing includes the power transmitted during energy transmission. The advantage here is that, in the event of danger, information can be displayed accordingly, the transmitted electrical power can be reduced or the transmission can be switched off.

In an advantageous embodiment, protective means are arranged on the surface area, which surround, in particular enclose, the secondary winding. The advantage here is that the security is further increased, since no foreign bodies can penetrate and therefore no dangerous heating takes place. The risk of fire is thus further reduced. Because protection by means of sensor monitoring is also supplemented by mechanical protection.

In an advantageous embodiment, a protective device can be extended so that the minimum distance between the protective device and the floor is reduced, or it can be retracted so that the minimum distance between the protective device and the floor is increased. The advantage here is that the protective device can be retracted when the vehicle is moving and thus itself is in turn protected. In addition, the friction can be reduced. In particular, the protective means can be arranged in the retracted state in such a way that the air friction of the vehicle is very low.

In an advantageous embodiment, the extension can be carried out passively, in particular brought about by the spring force of a spring element. The advantage here is that no additional actuator is required.

In an advantageous embodiment, the protective means and the spring element are made in one piece. The advantage here is that the number of parts is small and production is simple.

In an advantageous embodiment, the retraction can be carried out actively, in particular caused by the force generated by an actuator. The advantage here is that the point in time of retraction can be specified by a controller.

In an advantageous embodiment, the secondary winding is designed as a flat winding, in particular with only a single winding level. The advantage here is that simple production is possible.

In an advantageous embodiment, plate-shaped means or round means, such as bellows, are used as protective means. The advantage here is that a round spring can be integrated in the bellows and / or the plastic of the bellows can be made elastic, so that the extension can be carried out automatically and the retraction can be carried out easily. In addition, only a single bellows is sufficient as a protective means and each side does not have to be protected individually.

In an advantageous embodiment, each protective means is rotatably mounted on the vehicle. The advantage here is that the protective means can be folded down. For example, the protective means can be arranged as a polygon, in particular a triangle, square or the like, around the secondary coil. A swivel joint can be assigned to each side.

In an advantageous embodiment, a force can be applied to the protective means by means of an actuator which exceeds a spring force generated by a spring element,
in particular so that when the actuator is switched off, the protective means is extended by means of the spring force,
in particular so that the protective means can be retracted when the actuator is switched on. The advantage here is that the extension and retraction can be controlled in a simple manner.

In an advantageous embodiment, the actuator is a linear actuator. The advantage here is that a simple, inexpensive means, in particular an electrically controllable means, can be used.

In an advantageous embodiment, the primary conductor is designed as a flat winding. The advantage here is that a compact design can be achieved.

In an advantageous embodiment, the secondary winding of the vehicle has a capacitance connected in series or in parallel in such a way that the associated resonance frequency is essentially the same as the frequency of a primary current impressed in the primary conductor, in particular where the frequency is between 10 and 500 kHz, in particular where the primary current is 10 Ampere exceeds. The advantage here is that high powers can be transmitted without contact and with a high degree of efficiency.

In an advantageous embodiment, the protective means is designed as a magnetic shield, in particular so that when the protective means is extended, the spatial area generated by a primary winding of the primary conductor in the area encompassed by the protective means or the protective means, as well as the floor and surface area of the vehicle, does not escape into the environment, or only emerges in a weak manner. The advantage here is that the entry of objects is prevented and thus the risk of fire is reduced. Therefore, the security is increased.

In an advantageous embodiment, the protective means is made of plastic, in particular with an admixture of metallic particles for magnetic shielding, in particular with the metallic particles containing aluminum and / or iron. The advantage here is that a shielding of the magnetic field can be achieved and the plastic can nevertheless be used as a spring means.

In an advantageous embodiment, locking bolts are arranged on the vehicle for locking the protective means in the retracted state. The advantage here is that the safety can also be increased when the vehicle is in motion by actuating locking bolts. In this way, the retracted state of the protective means can even be provided for with double safety. Because on the one hand the linear actuator causes a fixation and on the other hand the fixation can be effected by means of the locking bolts.

Further advantages result from the subclaims. The invention is not restricted to the combination of features of the claims. For the person skilled in the art, there are further sensible possible combinations of claims and / or individual claim features and / or features of the description and / or the figures, in particular from the task and / or the task posed by comparison with the prior art.

• In der 1 ist ein Fahrzeug 1 gezeigt, welches berührungslos vom Boden aus mit Energie versorgt wird. Der Bereich der berührungslosen Energieübertragung ist mit einem Schutzmittel 3 abgegrenzt von der Umgebung.
• In der 2 ist eine zugehörige Seitenansicht gezeigt.
• In der 3 ist eine Schrägansicht von unten gezeigt, wobei der Boden ausgeblendet ist.
• In der 4 ist ein weiteres Fahrzeug gezeigt, wobei das Schutzmittel nun als runder ausgefahrener Faltenbalg 40 ausgeführt ist.
• In der 5 ist wiederum eine zur 4 gehörige Schrägansicht von unten gezeigt, wobei der Boden ausgeblendet ist.
• In der 6 ist das Fahrzeug nach 4 gezeigt, wobei der Faltenbalg eingefahren ist
• In der 7 ist eine zur 4 gehörige Schrägansicht von unten gezeigt.

The invention will now be explained in more detail with reference to figures:

• In the 1 is a vehicle 1 shown, which is supplied with energy from the ground without contact. The area of contactless energy transfer is covered with a protective means 3 separated from the surrounding area.
• In the 2 an associated side view is shown.
• In the 3 a perspective view from below is shown with the bottom hidden.
• In the 4th Another vehicle is shown, with the protective means now as a round extended bellows 40 is executed.
• In the 5 is again a for 4th Corresponding oblique view shown from below, wherein the bottom is hidden.
• In the 6th is the vehicle after 4th shown with the bellows retracted
• In the 7th is a for 4th Corresponding oblique view shown from below.

As in the first embodiment according to the 1 to 3 shown shows the vehicle 1 bikes 2 on which it is on a floor 4th is movable.
There is a secondary coil on its bottom 6th attached, which is preferably designed as a flat winding. For protection, the winding is at least surrounded by potting compound. In the vehicle 1 a capacitance is connected in series or in parallel to the coil winding in such a way that the associated resonance frequency is essentially the same as the frequency of a primary current. The frequency used is preferably a frequency between 10 and 500 kHz, particularly preferably between 15 and 30 kHz.

The primary current is fed into a primary conductor winding which can be weakly coupled to the coil winding of the vehicle and which is designed as a flat winding and in the ground 4th is inserted. This is also protected with potting compound in the floor. The weak coupling results from the large air gap for the magnetic field lines generated by the primary current.

Currents of more than 10 amperes, in particular of more than 30 amperes, are provided in the primary conductor.

This means that metallic objects that occur in the field area of the primary winding can be dangerously heated.

To protect against the penetration of objects into the room area in which high magnetic field strengths occur, protective means are arranged on the vehicle. As shown in the figures, four plate-shaped protective means are arranged on a square base area that borders the secondary winding, in particular on the underbody of the vehicle.

These means of protection 3 are folded down when the energy is transferred to the vehicle without contact. This means that the space mentioned is protected.

In a first embodiment, the folding down is achieved in that the protective means is rotatably mounted on the vehicle. A rotary movement is therefore driven to fold it down. For example, a rotary drive can be provided on the swivel joint axis. Alternatively, a spring element is used, so that after the protective means has been released, the rotary movement is brought about by the spring element. An actuator, for example a linear actuator, generates the restoring force for folding up after the energy transfer to the vehicle has ended.

In a second embodiment, the protective means is elastically deformable and folds down due to its integrated spring force. An actuator, for example a linear actuator, in turn generates the restoring force for folding up.

In the 4th to 7th Another embodiment is shown in which instead of the four plate-shaped protection means 1 to 3 a round means of protection 40 is provided, in particular that is designed as a bellows. This bellows can be extended towards the floor and thus the area around the secondary winding can be protected against the ingress of foreign bodies. The extension can be carried out by the force of weight. A spring force can be provided to accelerate the extension movement.

The retraction, that is to say the return movement, is in turn initiated and controlled by an actuator, for example a linear actuator.

In further exemplary embodiments according to the invention, the protective means ( 3 , 40 ) protected room area sensors 50 intended for monitoring the room area.

In a first variant, as sensors 50 ultrasound-sensitive sensors are used here, so that the entry of objects into the room area can be detected and a corresponding warning message can be displayed or forwarded.

After the vehicle has stopped, the sensors are activated, calibrated and thus detect the changes during the transfer.

In addition to or instead of the ultrasonic sensors, infrared sensors with a corresponding function can be attached.

A smoke detector can also be provided for monitoring the room area, so that a corresponding warning message can be triggered and / or displayed in the event of a fire hazard. In particular, the primary current can be switched off in that the vehicle transmits the warning message to an electronic control which is connected to the feed, which feeds the primary current into the primary conductor.

Furthermore, thermal sensors can also be provided which detect the heating of substances and thus make a fire hazard avoidable.

In addition, the secondary winding and / or the stationary primary winding can also be used as a sensor coil. For this purpose, high-frequency pulses are modulated so that eddy currents are induced in metallic parts that penetrate into the spatial area of the magnetic field generated by the primary winding. The eddy currents in turn cause a signal change in a receiving coil, which can be measured as a voltage immediately after switching off the transmission pulse. The receiving coil can be provided on the vehicle, in particular in the area or next to the secondary coil. Overall, the presence and / or the appearance or disappearance of metallic objects can thus be detected. The type of metals, their volume or other parameters of the metallic objects can even be detected.

In a further exemplary embodiment according to the invention, high-frequency alternating current components are also modulated on instead of the pulses mentioned. This enables continuous monitoring of the inductance. A change in inductance, for example caused by objects penetrating or exiting the space between the primary winding and the secondary winding, thus enables the space to be monitored. If a critical level of change in inductance is exceeded, a warning or other action can be triggered. In a further development, even several different frequencies are modulated and thus further information about the object that has entered the room area.

In a first exemplary embodiment, the aforementioned high-frequency current components are modulated onto the primary current of the primary winding. Here, high frequency means a respective frequency that is higher than the medium frequency impressed in the primary conductor for the transmission of energy to the vehicle. A frequency between 10 and 500 kHz can be used as the center frequency, preferably a frequency between 15 and 30 kHz. Alternatively, modulation to the current in the secondary winding is also possible. As a further alternative, separate coils can also be provided for introducing the high-frequency current components, in which case no modulation is carried out.

With the mentioned methods of the modulated pulsed and / or continuous alternating current components, the magnetic permeability and the electrical conductivity of the objects can be determined in a simple manner. Furthermore, the change in temperature can be determined by repeatedly executing the measurement at time intervals.

In a further development, a signal can be used as the high-frequency, pulsed and / or continuous alternating current component, which signal is used for the transmission of information between the stationary system part and the vehicle. In this case, a corresponding evaluation of the signal curve is carried out only for the received signal component. No additional effort is therefore necessary.

In particular, the level of the received signal can be monitored. Changes in the signal level indicate that objects have penetrated. The heating of the object and / or the type of material can even be determined.

List of reference symbols

1

vehicle

2

wheel

3

Protective agent

4th

ground

6th

Secondary coil

40

Protective means, in particular bellows

50

Sensors

Claims (13)

Arrangement for contactless energy transfer from a primary conductor laid on the ground to a vehicle, wherein the vehicle has a secondary winding on its surface area facing the ground, which can be inductively coupled to the primary conductor, in particular by approaching a vehicle position by means of the vehicle, wherein a sensor is arranged in a space between the secondary winding and the primary conductor, which is surrounded by protective means and can be monitored by the sensor, wherein a protective means can be extended so that the minimum distance between protective means and floor can be reduced, or can be retracted so that the minimum distance between protective means and floor is increased, wherein by means of an actuator, a force can be applied to the protective means which exceeds a spring force generated by a spring element, - So that when the actuator is switched off, the protective means is extended by means of the spring force and - so that the protective device can be retracted when the actuator is switched on. Arrangement according to at least one of the preceding claims, characterized in that the sensor is a smoke detector and / or that the sensor is an ultrasonic sensor. Arrangement according to at least one of the preceding claims, characterized in that the sensor has a receiving coil which makes signals from a transmitting coil receivable. Arrangement according to at least one of the preceding claims, characterized in that that the primary conductor or the secondary winding is used as the transmitting coil and / or that the primary conductor or the secondary winding is used as the receiving coil. Arrangement according to at least one of the preceding claims, characterized in that means for generating pulse-shaped current components are provided which are connected to the transmitter coil, in particular wherein the pulse-shaped current components are modulated onto the current of the primary conductor or the secondary winding, and / or that means for Generation of current components, in particular periodic current components, are provided which are connected to the transmitter coil and have a higher frequency than the frequency of the alternating current impressed in the primary conductor, in particular these current components being modulated onto the current of the primary conductor or the secondary winding. Arrangement according to at least one of the preceding claims, characterized in that the output signals of the sensor are fed to a control unit which is connected to means for triggering an action, in particular wherein the action involves displaying warning information, forwarding warning information via fieldbus, switching off Comprises means for energy transmission and / or a reduction in the power transmitted during energy transmission. Arrangement according to at least one of the preceding claims, characterized in that a protective means is made of such a material that the sensitive area of the sensor is restricted to the spatial area delimited by the protective means, in particular wherein the material is impermeable or reflective for the matter that can be detected by the sensor, such as gas or smoke, and / or radiation fields, such as magnetic fields, ultrasound, visible light, and / or infrared, in particular with the sensor being arranged in the spatial area surrounded by the protection means, in particular with the protection means having a metallic surface coating on its inside are, in particular on their surface facing the surrounding area, or wherein the protective means are made of metal. Arrangement according to at least one of the preceding claims, characterized in that protective means are arranged on the surface area which surround, in particular enclose, the secondary winding. Arrangement according to at least one of the preceding claims, characterized in that the extension can be carried out passively, in particular brought about by the spring force of a spring element. Arrangement according to at least one of the preceding claims, characterized in that the protective means and the spring element are made in one piece. Arrangement according to at least one of the preceding claims, characterized in that the retraction can be carried out actively, in particular caused by the force generated by an actuator, and / or that the secondary winding is designed as a flat winding, in particular with only a single winding level, and / or that plate-shaped means or round means, such as bellows, are used as protective means. Arrangement according to at least one of the preceding claims, characterized in that each protective means is rotatably mounted on the vehicle. Arrangement according to at least one of the preceding claims, characterized in that the actuator is a linear actuator and / or that the primary conductor is designed as a flat winding. 14. Arrangement according to at least one of the preceding claims, characterized in that the secondary winding of the vehicle has a capacitance connected in series or in parallel in such a way that the associated resonance frequency is essentially the same as the frequency of a primary current impressed in the primary conductor, in particular where the frequency is between 10 and 500 kHz, in particular with the primary current exceeding 10 amperes and / or that the protective means is designed as a magnetic shield, in particular so that when the protective means is extended, the protective means or the protective means as well as the floor and surface area of the vehicle encompass the one generated by a primary winding of the primary conductor The area of the room does not leak into the surroundings or is only weakened, and / or that the protective means is made of plastic, in particular with an admixture of metallic particles for magnetic shielding, in particular wherein the metallic particles contain aluminum and / or iron, and / or that the protective means is made of plastic that is metallically coated, and / or that Locking bolts are arranged on the vehicle for locking the protective means in the retracted state.

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