Method for detecting an object to be charged and associated charging device

Abstract

The invention proposes a method for detecting an object to be charged (T) by an inductive charging device (D) comprising at least one transmitting coil (B1, B2, B3), the method comprising transmitting an electrical pulse (DP) by the at least one coil (B1, B2, B3), the value of the electrical pulse (DP) being within a window (Vmin, Vmax) of predetermined values using a test receiver, and the object to be charged (T) generating a communication signal (SSP) in response, the method comprising a modulation of the value of the electrical pulse (DP) outside the window (Vmin, Vmax) of predetermined values depending on the presence and / or value of the communication signal (SSP) if charging conditions are favorable (Q, ΔR, ΔL, ΔFres) in order to detect the presence of the object to be charged (T).

Description

Technical Field

[0001] The field of this invention is the field of magnetic induction charging devices. In particular, the present invention relates to a method for detecting an object to be charged that is positioned close to a magnetic induction charging device, and an associated charging device. Background Technology

[0002] Magnetic induction charging technology is implemented in a system comprising a wireless charging device and an electrical storage battery to be charged in a mobile terminal, such as a portable item such as a mobile phone. The charging device includes a transmitting coil or a transmitting coil. The electrical storage battery includes a receiving coil to be charged. When the transmitting and receiving coils are positioned relative to each other, a change in the magnetic field generated by the transmitting coil causes a current to flow in the receiving coil, thereby charging the electrical storage battery.

[0003] Inductive charging technology meets the requirements of the standard, in this case, the Wireless Power Union's Qi® standard, also known as the WPC standard.

[0004] To detect the presence of an electrical storage battery, including a receiving coil positioned relative to the transmitting coil of a charging device, three steps are currently implemented.

[0005] In the first step, existing methods attempt to detect the presence of an object positioned relative to the charging device. For this purpose, an electrical pulse—also known as an “analog ping” or “AP”—is sent at the charging frequency via the charging device’s transmission coil to the receiving coil. An analog ping is a continuous signal that exhibits periodic oscillations with a period of, for example, 300 ms and an oscillation time of 5 to 20 ms. The voltage or impedance at the transmission coil terminals is observed. If a change in voltage at the transmission antenna terminals or in the transmission coil impedance is detected, then an object is present relative to the transmission coil.

[0006] In the second step, each transmitting coil of the charging device sends a "digital ping" or "DP" to make it possible to detect the presence of a compatible object to be charged on the charging surface of the device. A digital ping is also an electrical pulse, but it requests a response from the object to be charged. This makes it possible to identify whether an object placed on the charging surface is a compatible object to be charged, and which transmitting coil is best coupled to the receiving coil of the object to be charged.

[0007] Specifically, the detected object can be a parasitic object or a mobile device, such as a mobile phone equipped with a receiving coil for inductive charging. In this second step, an effort is then made to establish digital communication with the detected object in order to identify its characteristics. More specifically, an attempt is made to determine whether the detected object has a receiving coil for inductive charging in order to charge it. This communication is achieved by modulating the voltage amplitude across the terminals of the transmitting coil to send electrical pulses (digital pings). Next, in the event of favorable coupling between one of the transmitting coils and the receiving coil, the object to be charged returns a communication signal to the charging device, known as a “signal strength packet” or SSP signal. The SSP communication signal is the value returned by the object to the charging device and represents the coupling between its receiving coil and one of the transmitting coils of the charging device. The SSP communication signal corresponds to the ratio of the rectifier voltage to the maximum voltage allowed by the manufacturer of the object to be charged, which converts the AC (alternating current) voltage induced by receiving the digital pings in the receiving coil into a DC voltage.

[0008] If the charging device does not receive the SSP communication signal, it considers the object placed on the charging surface to be a parasitic object, i.e., an object incompatible with charging, and inductive charging is not activated.

[0009] Specifically, this occurs when the object to be charged is located in an area where the coupling between the transmitting and receiving coils on the charging surface is too weak.

[0010] To trigger the transmission of the SSP communication signal, according to the Wireless Power Union's Qi® standard—the global standard for inductive charging—the digital ping DP sent by the charging device should observe the voltage level induced in the object to be charged, as set by the manufacturer, and this should be within a predetermined duration. More precisely, the digital ping should last between 65 ms and 93 ms. During this time, the voltage induced in the object to be charged should not exceed the threshold set by the manufacturer, and the charging device should receive a single SSP communication signal from the object to be charged.

[0011] Therefore, according to the same standard, in order to obtain Qi certification, there are defined minimum and maximum levels for the rectified voltage within the object to be charged. These minimum and maximum levels should be observed when the charging device transmits a digital ping DP. These minimum and maximum rectified voltage levels are checked during the certification phase for four types of test receivers, and depending on the type of test receiver, they are generally between 3V and 9V or between 3V and 15V.

[0012] Therefore, for each test receiver placed on the charging surface of the charging device to be certified, the voltage value of the transmitted digital ping DP will be determined such that the rectified voltage Vr induced in the receiver is completely within the limits specified by the Qi standard in order to pass Qi certification.

[0013] However, this testing and certification has the following drawbacks:

[0014] a. The test receiver is perfectly centered relative to each transmitting coil.

[0015] b. The test receiver does not contain any metal parts.

[0016] Therefore, magnetic field loss is minimized, and almost all the magnetic field emitted by the transmitting coil is received by the receiving coil. Thus, the test certification is performed under optimal conditions.

[0017] Therefore, when using a digital voltage ping defined in that manner on a typical object to be charged (such as a cellular phone or tablet), a portion of the magnetic field is dissipated, and the rectified voltage of the object to be charged is thus reduced. This object may be off-center relative to the transmitting coil or may contain metal components. The value of the rectified voltage is then too low for the object to transmit SSP communication signals. This is in… Figure 1 The diagram shows the object to be charged, T, located at one end of the charging surface of the charging device D. Therefore, the receiving coil A1 is not sufficiently aligned with one of the three transmitting coils B1, B2, and B3 of the charging device D.

[0018] Because no SSP communication signal was sent, the object to be charged was considered a parasitic object, and charging did not begin.

[0019] This lack of detection effect occurs particularly when the object to be charged (or more precisely, the receiving coil) is located in the area between the transmitting coils, or in the area furthest from the transmitting coils, and more specifically in the four corners of a rectangular charging device. Now, in the case of onboard charging equipment for motor vehicles, the object to be charged is placed in an unfixed position on the charging surface, and when the vehicle moves, the object will slide across the charging surface and may terminate in one of the corners of the charging device, where charging will not begin, or if it was previously active, it will stop.

[0020] Conversely, due to the inherent construction of the device being charged, very strong coupling can occur between the transmitting and receiving coils, where each cellular phone has its own characteristics. In such a case, the rectified voltage induced by the digital ping defined during the certification phase may exceed the limits specified by the standard, triggering a protection mode in the device being charged that will not transmit SSP communication signals, and therefore charging will not begin. This strong coupling effect can occur when the receiving coil is very large and has the same geometry as the transmitting coil, or when the receiving coil has a very high quality factor, or when the distance between the receiving and transmitting coils is small, and so on.

[0021] In the third step, charging begins when digital communication is established between the transmitting and receiving coils of the detected object via receiving SSP communication signals.

[0022] Therefore, it is necessary to overcome the shortcomings of the prior art by means of a method for detecting the object to be charged, which allows charging to be initiated using any compatible object to be charged on the entire charging surface of the charging device. Summary of the Invention

[0023] The present invention proposes a method for detecting an object to be charged by an inductive charging device including at least one transmitting coil. The method includes transmitting an electrical pulse by at least one coil, the value of which is within a window of values ​​predetermined using a test receiver, and the object to be charged generating a communication signal in response. Notably, if the charging conditions are favorable, the method includes modulating the value of the electrical pulse outside the window of predetermined values ​​based on the presence and / or value of the communication signal in order to detect the presence of the object to be charged.

[0024] The charging device includes at least one transmitting coil; notably, the method includes the following steps for each coil:

[0025] a. Detect the presence of an object on the charging surface of the device;

[0026] b. Check charging conditions;

[0027] c. If charging conditions are favorable:

[0028] d. Then an electrical pulse is emitted to the object, the value of which is within a window of values ​​predetermined by the test receiver;

[0029] e. If the object emits a communication signal below its maximum value in response, then an object to be charged is detected; otherwise:

[0030] f. In the absence of a communication signal or a communication signal with a maximum value, a modified electrical pulse whose value is outside the window of a predetermined value is then transmitted to the object:

[0031] g. If the object transmits a communication signal in response, then the object to be charged is detected;

[0032] h. Otherwise, a parasitic object was detected.

[0033] In the absence of a communication signal, the modified electrical pulse has a voltage higher than the upper limit predetermined by the test receiver.

[0034] If the object transmits a communication signal at its maximum value, the modified electrical pulse has a voltage lower than a pre-determined lower limit using a test receiver.

[0035] If charging conditions are unfavorable, then the modified electrical pulse will have a voltage lower than the lower limit predetermined by the test receiver.

[0036] When charging conditions are unfavorable to the coil, the method is stopped for the coil.

[0037] The charging device includes multiple transmitting coils, and the method is repeated for each coil.

[0038] The method includes a prior step of calibrating the voltage value of the modified electrical pulse outside a window of predetermined values ​​according to various types of objects to be charged.

[0039] The check for favorable charging conditions includes measuring at least one parameter of at least one transmitting coil and comparing the measurement with a predetermined threshold of the same parameter obtained in advance for various types of objects to be charged.

[0040] This parameter can be the quality factor of the transmitting coil, and / or variations in resistance, and / or inductance, and / or variations in resonant frequency.

[0041] The present invention is also applied to a device for charging an object, comprising at least one transmitting coil, and notably, it comprises:

[0042] a. A component used to detect objects on a charging surface;

[0043] b. And, for each coil:

[0044] c. A component used to check charging conditions;

[0045] d. A component for detecting the reception of a communication signal and for comparing the value of the received communication signal with a maximum value;

[0046] e. A component for modulating the value of an electrical pulse emitted by at least one coil outside a window of values ​​predetermined using a test receiver, based on the results of the inspection and the presence and / or value of the communication signal.

[0047] The inspection component includes a component for measuring at least one parameter of the transmitting coil, and a component for comparing the measurement with a predetermined threshold of the same parameter obtained in advance for various types of objects to be charged.

[0048] This parameter can be the quality factor of the transmitting coil, and / or variations in resistance, and / or inductance, and / or variations in resonant frequency.

[0049] The present invention also relates to a computer program product comprising program code instructions which, when executed on a computer, are used to perform steps of a detection method according to any of the features given above.

[0050] Finally, the present invention is applicable to any motor vehicle including a charging device according to any of the features given above. Attached Figure Description

[0051] Other features and advantages of the invention will become more apparent from reading the following description. This description is purely illustrative and should be read with reference to the accompanying drawings, in which:

[0052] [ Figure 1 ]: Figure 1 The object T to be charged is schematically shown at one end of the charging device D;

[0053] [ Figure 2 ]: Figure 2 It is a graph showing the digital ping of the same voltage value transmitted by each transmitting coil according to the prior art;

[0054] [ Figure 3 ]: Figure 3 This is a graph showing the modified digital ping transmitted by each transmitting coil according to a first variation of the detection method according to the invention;

[0055] [ Figure 4 ]: Figure 4 This is a graph showing modified digital pings transmitted by each transmitting coil, according to a second variation of the detection method according to the invention;

[0056] [ Figure 5 ]: Figure 5 This is a flowchart illustrating the various steps of the detection method according to the present invention;

[0057] [ Figure 6a ]: Figure 6aThe detection area of ​​the object to be charged on the charging surface of a charging device according to the prior art is schematically shown.

[0058] [ Figure 6b ]: Figure 6b The detection area of ​​the object to be charged on the charging surface of the charging device according to the present invention is schematically shown. Detailed Implementation

[0059] As explained above, charging initiation or charging of an object can be disabled because the rectified voltage value Vr of the object to be charged, sensed by the digital ping emitted by the charging device, is higher or lower than the limits set by the object's manufacturer via the Qi standard. To avoid exceeding these limits, the voltage value of the digital ping is predetermined using a test receiver during the Qi standard certification phase.

[0060] The problem of charging not being initiated is primarily due to the inherent construction of the object to be charged T (the size of the receiving coil, the coil's position within the object, objects with high metal components) and / or its position on the charging surface S of the charging device D. These are actual charging conditions that differ significantly from the optimal charging conditions used during the certification phase.

[0061] This invention proposes a method for detecting an object T to be charged and a charging device D, which makes it possible to overcome the disadvantages mentioned above.

[0062] Therefore, the charging device D according to the invention includes at least one transmitting coil B1 and a component for controlling the coil, i.e., a component for generating and controlling charging, i.e., an electromagnetic field directed towards the object T to be charged. This is known from the prior art and will not be described in more detail here.

[0063] The charging device D includes a charging surface S on which the object T to be charged is placed. The object can be a smartphone, a tablet, or even any connected object that can be charged using the Qi standard (i.e., the Wireless Power Alliance standard for inductive charging).

[0064] The charging device D is intended to be installed on a motor vehicle, and for this purpose, its charging surface is sized to accommodate any type of object T to be charged, regardless of its size. In this example, the device does not include any components for fixing or holding the object T to be charged to the charging surface S. Therefore, most objects T placed on the charging surface S will be able to slide freely on the surface S depending on the movement of the vehicle. Specifically, especially with this type of charging device D, a problem arises where charging initiation is prohibited because, as the vehicle moves, the object T to be charged may move into a corner of the charging device and charging stops, as explained above.

[0065] According to the present invention, the charging device D includes components M1 for detecting that an object has been placed on the charging surface S. These detection components consist of components for transmitting electrical pulses (i.e., simulating ping) and components for measuring parameters (such as changes in the voltage, impedance, or resonant frequency of the transmitting coil). The detection components M1 may also include sensors, such as capacitive sensors, components for detecting GSM (Global System for Mobile Communications) coupling, i.e., components for detecting 2G communication with a cellular phone or NFC antenna. These detection components are known to those skilled in the art and will not be described in more detail herein.

[0066] Device D also includes a component M2 for checking the charging conditions of each coil. In this example, device D equipped with three transmitting coils B1, B2, and B3 will be considered, such as... Figure 1 As shown in the diagram.

[0067] These components M2 consist of parameter measurements of transmitting coils B1, B2, and B3, such as:

[0068] a. The quality factor Q of coils B1, B2, and B3; and / or

[0069] b. The resistance change ΔR of the coil; and / or

[0070] c. The inductance change ΔL of the coil; and / or

[0071] d. The change in the resonant frequency of the coil, ΔFres;

[0072] And components for comparing these measurements with predetermined thresholds.

[0073] The “variation” in the parameters of resistance ΔR, inductance ΔL, and resonant frequency ΔFres means, for each of these parameters, the difference between the “no-load” value of the parameter—that is, when no object is placed on the charging surface S—and the value of the same parameter when an object is placed on the charging surface S.

[0074] The predetermined thresholds are the minimum and maximum values ​​predetermined for each coil and various types of objects to be charged, such as various types of cellular phones with or without protective metal casings, phones with few or no metal parts, or phones with many metal parts, phones with small or very large receiving coils, etc.

[0075] For example, the quality factor Q1 of the first coil B1 is compared with the minimum value Q1min and the maximum value Q1max that are predetermined for the same first coil B1.

[0076] Similarly, the resistance change ΔR1 of the first coil B1 is compared with the minimum resistance change ΔR1min and the maximum resistance change ΔR1max, which are predetermined for the same first coil B1.

[0077] This similarly applies to the inductance change ΔL and resonant frequency change ΔFres for each of the three coils B1, B2, B3, as will be explained further.

[0078] The device also includes component M3 for detecting the reception of SSP communication signals and comparing the value of the received communication signal with a maximum value SSPmax. The detection and comparison component includes a demodulator for demodulating the received communication signal and a software component for comparing the value of the signal with a predetermined maximum value SSPmax.

[0079] Finally, the charging device D includes a component M4 for modulating the value of the electrical pulse or digital ping emitted by each of the coils B1, B2, B3 outside a predetermined value window, which has been predefined using a test receiver during the Qi standard certification phase. One or more coils then emit the modified electrical pulse DPm. The modulation of the electrical pulse value is performed based on the results of the advantageous checks and on the presence and / or value of the SSP communication signal. "Value" means, for example, the voltage of the electrical pulse.

[0080] The modulation component M4 may include a modified electrical pulse value DPm, which is outside a window of predetermined values, depending on the various types of objects T to be charged. Thus, the component used to check the charging conditions of M2 can indicate the type of object to be charged, and then select the voltage of the applied modified electrical pulse DPm from values ​​pre-calibrated according to the type of object T and stored in the charging device (e.g., in the modulation component M4).

[0081] The component M2 for checking favorable conditions, the component M3 for detecting the reception of SSP communication signals and for comparing the value of the received communication signals with the maximum value SSPmax, and the component M4 for modulating the electrical pulse value are preferably in the form of software and based on a microcontroller located in the device D.

[0082] Now will describe Figure 5 The diagram illustrates a method for detecting an object T to be charged.

[0083] In the preceding step (step E0), it is detected that an object has been placed on the charging surface S of the charging device D. This object can be an object to be charged—that is, an object compatible with inductive charging according to the Qi standard—but it can also be a “parasitic” object, such as a paperclip or a coin.

[0084] This detection is achieved by transmitting simulated ping-type electromagnetic pulses at a regular frequency through the transmitting coils B1, B2, and B3 of the charging device D and measuring changes in parameters such as voltage, impedance, or resonant frequency. Alternatively, this detection can be achieved using a capacitive sensor or other components for detecting the presence of an object. If a significant change in these parameters is measured, it means that the object has been detected as being placed on the charging surface S.

[0085] In the first step E1, the detection method according to the present invention proposes to check the so-called "ambient" charging conditions.

[0086] In this step, parameters are measured for each transmitting coil B1, B2, B3 in the first stage, such as:

[0087] a. The quality factor Q of coils B1, B2, and B3; and / or

[0088] b. The resistance change ΔR of the coil; and / or

[0089] c. The inductance change ΔL of the coil; and / or

[0090] d. The resonant frequency change ΔFres of the coil.

[0091] According to the present invention, charging conditions can be checked using only one parameter, or a combination of two, three, or four parameters. The number or type of parameters can vary depending on the transmitting coils B1, B2, and B3 discussed.

[0092] Next, in the second stage, the measured values ​​for each transmitting coil B1, B2, B3 are compared with predetermined thresholds.

[0093] Thresholds have been pre-determined for various types of objects T to be charged that exhibit different characteristics, namely: telephones with few metal parts, telephones with many metal parts, telephones with a large receiving antenna A1, or telephones with a small receiving coil A1.

[0094] Therefore, for each receiving coil B1, B2, B3, it is possible to check:

[0095] [Mathematics 1]

[0096] in

[0097] Qi: The quality factor of the i-th coil

[0098] Qimin: The minimum quality factor of the i-th coil.

[0099] Qimax: The maximum quality factor of the i-th coil.

[0100] Similarly, an inspection is also possible:

[0101] [Mathematics 2]

[0102] in

[0103] ΔRi: The change in resistance of the i-th coil

[0104] ΔRimin: The minimum change in resistance of the i-th coil

[0105] ΔRimax: The maximum change in resistance of the i-th coil.

[0106] Similarly, it is possible to check:

[0107] [Mathematics 3]

[0108] in

[0109] ΔLi: Change in inductance of the i-th coil

[0110] ΔLimin: The minimum change in the inductance of the i-th coil

[0111] ΔLimax: The maximum change in inductance of the i-th coil.

[0112] Finally, it's possible to check:

[0113] [Mathematics 4]

[0114] in

[0115] ΔFresi: The change in the resonant frequency of the i-th coil

[0116] ΔFresimin: The minimum change in the resonant frequency of the i-th coil.

[0117] ΔFresimax: The maximum change in the resonant frequency of the i-th coil.

[0118] As explained above, for each of the transmitting coils B1, B2, and B3, checking only one parameter is sufficient to conclude that the charging conditions are favorable. The checks on these parameters may not necessarily be combined to determine whether the charging conditions are favorable.

[0119] Charging conditions are considered favorable for the transmitting coil when at least one inspection criterion is met.

[0120] Therefore, two scenarios are possible:

[0121] a. Either the charging conditions are favorable, and the method continues to step E3, wherein at least one of the coils B1, B2, B3 of the charging device D sends a digital ping DP;

[0122] b. Either the charging conditions are unfavorable, and the method stops (step E7b) and no coil emits a digital pingDP.

[0123] In a variation of this method, if the conditions are unfavorable, the method continues and proposes that the charging device transmits a modified digital ping DPm, the value of which (here, voltage) is lower than the (voltage) lower limit predetermined in the certification phase of the Qi standard using a test receiver, as explained above.

[0124] Once the charging conditions have been checked, if they are favorable—specifically, if one or more of the four parameters listed above are indeed within a predetermined threshold for at least one transmitting coil B1, B2, or B3 (step E2)—then the charging device D transmits a digital ping DP via that transmitting coil (step E3). If all coils meet the charging conditions, then each transmitting coil sequentially transmits a digital ping DP to the target (step E2).

[0125] If the object responds to the digital ping DP by sending a communication signal called an "SSP" ("Signal Strength Packet") signal (step E4a), which includes a signal representing the voltage value Vr induced by the received signal—which has a value lower than the maximum value SSPmax (step E4b)—then inductive charging is initiated (step E7a). Specifically, the "SSP" signal is a value representing the ratio of the rectified voltage value Vr induced by receiving the electromagnetic field created by the digital ping DP across the terminals of the voltage rectifier of the receiving coil A1 to the maximum rectified voltage that the object to be charged can withstand when receiving the digital ping DP.

[0126] In a first embodiment of the method according to the invention, if the object does not send an “SSP” signal, then it is either a parasitic object or a charging object that has a rectified voltage value Vr that is too low relative to the rectified voltage limit specified by the cellular phone manufacturer to initiate charging. This insufficiently high rectified voltage does not allow it to send an “SSP” communication signal to the charging device D to initiate charging.

[0127] In this case, if the object to be charged does not return an “SSP” communication signal, then according to the method of the invention, the charging device sends a modified digital ping DPm with a value higher than the upper limit determined in the certification phase (here, voltage), which will cause the rectified voltage Vr in the test receiver to be higher than the limit specified by the Qi standard.

[0128] Once the modified digital ping DPm has been sent, two scenarios are possible: either the object returns an SSP communication signal (step E6) and charging begins (step E7a), or no SSP communication signal is sent and charging is not initiated (step E7b).

[0129] Figure 2 The diagram shows the digital ping DP transmitted by each of the transmitting coils B1, B2, and B3 according to existing technology. All of these have the same voltage equal to the upper voltage limit Vmax defined during the certification phase, ensuring that all test receivers respond to the charging device D by transmitting an SSP signal, while their rectified voltage does not exceed the maximum value specified in the standard.

[0130] Figure 3 The diagram illustrates a first example of a modified digital ping DPm transmitted by each of coils B1, B2, and B3 according to the method of the invention. The value of the modified digital ping DPm varies from coil to coil, and in this case, each has a voltage higher than the prior art voltage upper limit Vmax. The voltage of the digital ping DPm has been increased by X1%, X2%, and X3% respectively relative to the voltage Vmax of the first coil B1, the second coil B2, and the third coil B3.

[0131] In a second embodiment of the method according to the invention, if the object to be charged returns an SSP signal with a maximum value SSPmax (step E4b), which is specified by the Qi standard and equal to SSPmax = 255 (the demodulator in the microcontroller of the charging device demodulates the SSP communication signal sent by the object to be charged and compares it with the maximum value 255), then the method proposes that the charging device D send a modified digital ping DPm, this time with a value lower than the lower limit Vmin (here, voltage) determined in the certification phase, which will cause the rectified voltage Vr in the test receiver to be lower than the limit specified by the Qi standard.

[0132] Figure 4 The diagram illustrates a second example of a modified digital ping DPm transmitted by each of coils B1, B2, and B3. The modified digital ping DPm varies from coil to coil, and in this case, each has a voltage lower than the prior art lower limit Vmin. The voltage of the digital ping has been reduced by Y1%, Y2%, and Y3% respectively relative to the lower limits Vmin of the first coil B1, the second coil B2, and the third coil V3.

[0133] Of course, the method may include a prior step of calibrating the voltage value of the modified electrical pulse DPm outside a predetermined window of values, defined by an upper limit Vmax and a lower limit Vmin according to various types of objects T to be charged. Thus, the charging conditions can indicate the type of object to be charged, and the applied voltage of the modified electrical pulse DPm can then be selected from pre-calibrated values ​​stored in the charging device according to the type of object T.

[0134] As explained above, for the transmitting coils B1, B2, and B3 of the same charging device D, it is also possible to transmit a modified digital ping with a voltage lower than or higher than the lower limit Vmin or upper limit Vmax of the prior art, or even for the coils to transmit no digital ping at all.

[0135] Figure 6a The diagram illustrates a region Z1 for placing an object T to be charged on the surface of a charging device D, which allows charging to be initiated according to existing technology.

[0136] Figure 6b The diagram illustrates region Z2 for placing the object T to be charged on the surface of the charging device D, which allows charging to be initiated using the detection method according to the invention. It is clearly apparent from comparing the two figures 6a and 6b that, by means of the detection method according to the invention, region Z2, which allows charging activation, is significantly larger than the prior art region Z1.

[0137] Therefore, the detection method according to the present invention allows for overcoming the shortcomings of the prior art. Specifically, the method of the present invention allows for better identification of compatible objects to be charged relative to parasitic objects placed on the charging surface, and most importantly, it allows for an increase in the size of the charging area on the charging surface of the charging device.

Claims

1. A method for detecting an object to be charged (T) via an inductive charging device (D) including at least one transmitting coil (B1, B2, B3), the method comprising transmitting an electrical pulse (DP) through the at least one coil (B1, B2, B3), the value of the electrical pulse (DP) being within a window (Vmin, Vmax) of predetermined values ​​using a test receiver during an authentication phase, and the object to be charged (T) generating a communication signal (SSP) in response, the method being characterized in that, if the charging conditions (Q, ΔR, ΔL, ΔFres) are favorable and in the absence of a communication signal (SSP) or a communication signal returning to its maximum value (SSPmax), it includes modulating the value of the electrical pulse (DP) outside the window (Vmin, Vmax) of predetermined values ​​to detect the presence of the object to be charged (T).

2. The method for detecting an object (T) to be charged by a charging device (D) according to claim 1, comprising at least one transmitting coil (B1, B2, B3), characterized in that, for each coil, the method comprises the following steps: a) Detect the presence of an object on the charging surface (S) of the device; b) Check the charging conditions (Q, ΔR, ΔL, ΔFres); c) If charging conditions are favorable: i) An electrical pulse (DP) is emitted to the object, the value of which is within a window (Vmin, Vmax) of a value pre-determined using a test receiver during the authentication phase; ii) If, in response, the object emits a communication signal (SSP) below the maximum value (SSPmax), then the object to be charged (T) is detected; otherwise: iii) In the absence of a communication signal (SSP) or a communication signal that returns to its maximum value (SSPmax), a modified electrical pulse (DPm) is then transmitted to the object whose value is outside the window of a predetermined value: a. If, in response, the object emits a communication signal (SSP), then the object to be charged (T) is detected. b. Otherwise, a parasitic object has been detected.

3. The detection method according to claim 2, characterized in that, In the absence of a communication signal (SSP), the modified electrical pulse (DPm) has a voltage higher than the upper limit (Vmax) predetermined in advance for use with the test receiver during the certification phase.

4. The detection method according to any one of claims 2 and 3, characterized in that, If the object transmits a communication signal at its maximum value (SSPmax), the modified electrical pulse (DPm) has a voltage lower than the lower limit (Vmin) predetermined in advance when using a test receiver during the certification phase.

5. The detection method according to any one of claims 2 and 3, characterized in that, If the charging conditions (Q, ΔR, ΔL, ΔFres) are unfavorable, then the electrical pulse has a voltage lower than the lower limit (Vmin) predetermined in advance when using the test receiver during the certification phase.

6. The detection method according to any one of claims 2 and 3, characterized in that, When the charging conditions (Q, ΔR, ΔL, ΔFres) are unfavorable to the coil, the method is stopped for the coil.

7. The detection method according to any one of claims 2 and 3, characterized by, The charging device (D) includes multiple transmitting coils (B1, B2, B3), and the method is repeated for each coil.

8. The detection method according to any one of claims 2 and 3, characterized by, It includes a prior step of calibrating the voltage value of a modified electrical pulse (DPm) outside a predetermined window according to various types of objects to be charged (T).

9. The detection method according to any one of claims 2 and 3, characterized in that, The check for favorable charging conditions includes measuring at least one parameter of the at least one transmitting coil (B1, B2, B3) and comparing the measurement with a predetermined threshold of the same parameter obtained in advance for various types of objects to be charged (T).

10. The detection method according to claim 9, characterized in that, The parameters are the quality factor (Q) of the transmitting coils (B1, B2, B3), and / or the change in resistance (ΔR) and / or the change in inductance (ΔL), and / or the change in resonant frequency (ΔFres).

11. A device (D) for charging an object, comprising at least one transmitting coil (Bl, B2, B3), characterized in that, It includes: a) A component (M1) for detecting an object on the charging surface (S); Furthermore, for each coil: b) Component (M2) used to check charging conditions (Q, ΔR, ΔL, ΔFres); c) A component (M3) for detecting the reception of a communication signal (SSP) and for comparing the value of the received communication signal with a maximum value (SSPmax). d) A component (M4) for modulating the value of an electrical pulse (DP) emitted by the at least one coil (B1, B2, B3) outside a window (Vmin, Vmax) of a pre-determined value of the test receiver during the authentication phase, based on the results of the inspection and the presence and / or value of the communication signal (SSP).

12. The device for charging an object according to claim 11, characterized in that, The component (M2) for checking charging conditions (Q, ΔR, ΔL, ΔFres) includes a component for measuring at least one parameter of the transmitting coil (B1, B2, B3), and a component for comparing the measurement with predetermined thresholds of the same parameters (Qmin, Qmax, ΔRmin, ΔRmax, ΔLmin, ΔLmax, ΔFresmin, ΔFresmax) obtained in advance for various types of objects to be charged (T).

13. The charging device (D) according to claim 12, characterized in that, The parameters are the quality factor (Q) of the transmitting coils (B1, B2, B3), and / or the change in resistance (ΔR) and / or the change in inductance (ΔL), and / or the change in resonant frequency (ΔFres).

14. A computer program product comprising program code instructions, wherein when the program is executed on a computer, the program code instructions are used to perform the steps of the detection method according to any one of claims 1 to 10.

15. A motor vehicle comprising a charging device (D) according to any one of claims 11 to 13.

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