Method for estimating power loss

Abstract

According to one aspect of the present invention, provided is a method for estimating power loss, comprising the steps of: obtaining information on at least one of an interval between a wireless power transmitter and a wireless power receiver and a rectified voltage of the wireless power receiver; and a step of estimating the power loss caused by the friendly metal with reference to the obtained information.

Description

Technical Field

[0001] The present invention relates to a method for estimating power loss. Background Art

[0002] The Wireless Power Consortium (WPC) is an international standardization organization for wireless power transmission. It developed the Qi standard, which is related to magnetic induction wireless charging. The Qi standard primarily defines the Baseline Power Profile (BPP) and the Extended Power Profile (EPP), and recently added the Magnetic Power Profile (MPP).

[0003] Magnetic induction wireless charging essentially requires a wireless power transmitter and a wireless power receiver, and there must be no foreign objects (FO) between them. The presence of FO between the two can not only degrade wireless charging performance but also pose significant safety risks.

[0004] The Qi standard specifies various methods for detecting foreign objects (FOD (Foreign Object Detection) methods) based on BPP and EPP. Regarding the FOD method based on MPP, the MPL A (MPP Power Loss Accounting) method is currently under discussion.

[0005] If the MPLA method discussed so far is referred to as the existing MPLA method, it requires an estimate of the power loss due to friendly metals (FM) in order to estimate (or infer) the power loss due to foreign matter. However, the linear model (i.e., linear fit curve) for the power loss due to friendly metals derived using the existing MPLA method exhibits significant deviations from actual results. This results in significant errors in the estimation of power loss due to friendly metals in practical applications, which directly degrades the performance of the FOD method. Summary of the Invention Technical issues to be solved by the invention

[0006] An object of the present invention is to solve all the problems of the above-mentioned conventional technologies.

[0007] Furthermore, another object of the present invention is to propose an improved MPLA method based on an analysis of the physical causes of errors in estimating (or inferring) the power loss caused by the friendly metal using the existing MPLA method. Means for solving technical problems

[0008] The representative configuration of the present invention for achieving the above-mentioned object is as follows.

[0009] According to one embodiment of the present invention, a method for estimating power loss is provided, comprising the steps of: obtaining information related to at least one of a distance between a wireless power transmitter and a wireless power receiver and a rectified voltage of the wireless power receiver; and estimating power loss caused by a friendly metal with reference to the obtained information.

[0010] According to another embodiment of the present invention, a wireless power transmitter is provided, comprising: an obtaining unit for obtaining information related to at least one of a distance between the wireless power transmitter and a wireless power receiver and a rectified voltage of the wireless power receiver; and an estimation management unit for estimating power loss caused by a friendly metal with reference to the obtained information.

[0011] According to another embodiment of the present invention, a method for estimating power loss is provided, comprising the steps of: obtaining information related to at least one of a distance between a wireless power transmitter and a wireless power receiver and a rectified voltage of the wireless power receiver; and estimating power loss caused by a friendly metal with reference to the obtained information.

[0012] According to another embodiment of the present invention, a wireless power receiver is provided, comprising: an obtaining unit for obtaining information related to at least one of a distance between a wireless power transmitter and a wireless power receiver and a rectified voltage of the wireless power receiver; and an estimation management unit for estimating power loss caused by a friendly metal with reference to the obtained information.

[0013] In addition, other methods, other wireless power transmitters, and other wireless power receivers for implementing the present invention are also provided. Effects of the Invention

[0014] According to the present invention, compared with the existing MPLA method, the improved MPLA method can demonstrate performance advantages from the perspective of RMSE (Root Mean Squared Error), and can be implemented in wireless power transmitters and wireless power receivers applicable to MPP to improve the performance of foreign object detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1is a diagram illustrating a loss split model (loss-split model) regarding a wireless power transmitter and a wireless power receiver.

[0016] Figure 2 is a diagram showing a linear model derived by the conventional MPLA method.

[0017] Figure 3 is a graph showing deviations present in a linear model of power loss due to friendly metals derived by the existing MPLA method.

[0018] Figures 4 to 7 This is a diagram schematically showing the components of a wireless power transmitter and a wireless power receiver.

[0019] Figure 8 is a diagram illustrating a process of deriving a linear model of power loss due to a friendly metal in the conventional MPLA method.

[0020] Figure 9 is a diagram showing a process of deriving a linear model of power loss caused by a friendly metal in the improved MPLA method.

[0021] Figure 10 is a diagram showing a linear model of power loss due to friendly metals derived by the improved MPLA method.

[0022] Figure 11 It is a diagram showing a linear model derived by the conventional MPLA method under GG conditions, TG conditions, and GR conditions.

[0023] Figure 12 is a diagram showing a linear model of power loss due to friendly metals derived by the existing MPLA method under TR conditions.

[0024] Figure 13 Graph showing a linear model of power loss due to friendly metals derived by the improved MPLA method under GG conditions, TG conditions, and GR conditions.

[0025] Figure 14 is a diagram showing a linear model of power loss due to friendly metals derived by the improved MPLA method under TR conditions. DETAILED DESCRIPTION

[0026] In the detailed description of the present invention described later, reference will be made to the accompanying drawings which illustrate specific embodiments in which the present invention may be implemented. Such embodiments are described in sufficient detail so that those skilled in the art can implement the present invention. The various embodiments of the present invention are different from each other, but it should be understood that the various embodiments do not necessarily exclude each other. For example, the specific shapes, structures and characteristics described in this specification may be implemented by changing from one embodiment to another embodiment without departing from the spirit and scope of the present invention. Furthermore, it should be understood that the position or configuration of the individual constituent elements in each embodiment may also be changed without departing from the spirit and scope of the present invention. Therefore, the detailed description described later is not intended to be limiting, but should be accepted as the scope of the present invention including the scope requested by the claims of the claims and all equivalents thereto. Similar reference symbols in the figures represent identical or similar constituent elements in various aspects.

[0027] In this specification, it should be noted that the term "estimate" can be used interchangeably with the terms "calculate," "calculate," or "measure," and vice versa, depending on the circumstances.

[0028] Hereinafter, in order to enable a person having ordinary knowledge in the technical field to which the present invention belongs to implement the present invention easily, several preferred embodiments of the present invention are described in detail with reference to the accompanying drawings.

[0029] Background of the Improved MPLA Method

[0030] MPP is a new power profile introduced in the Qi2 standard, based on discussions with Apple's MagSafe. Compared to existing BPP and EPP standards, MPP features the addition of magnets to align and secure the wireless power transmitter (hereinafter referred to as "transmitter" or "PTx") and wireless power receiver (hereinafter referred to as "receiver" or "PRx").

[0031] As explained in the technical section of the background of the invention, it is very important to establish a FOD method for MPP, just like for BPP and EPP. The existing MPLA method is being discussed as a FOD method for MPP, and its implementation plan is as follows.

[0032] In the existing MPLA method, the power loss P caused by foreign matter FO Estimated as the transmit power P PT and the received power P PR That is, P FO =P PT -P PR Here, P PT The transmitter is P PT =V INI IN -(P circuit loss，Tx +P coil loss，Tx +P FM ) is estimated by the relationship PR The receiver uses P PR =V RECT I RECT +P circuit loss，Rx +P coil loss，Rx That is, in order to estimate P FO , the transmitter needs to estimate the input voltage V IN 、Input current I IN , transmitter side circuit power loss P circuit loss，Tx , Transmitter side coil power loss P coil loss，Tx and the power loss P caused by the friendly metal FM Furthermore, the receiver needs to estimate the rectified voltage V RECT , rectified current I RECT , receiver side circuit power loss P circuit loss,Rx and the receiver side coil power loss P coil loss,Rx Under TR conditions (the details of TR conditions will be described later), P coil loss,Tx 、P coil loss，Rx and P FM Respectively Here, b coil 、m coil , α FM and α FM，DC It can be called MPLA coefficient or PLA coefficient, g coil,Tx 、g coil，Rx 、g FM and g FM，DC It can be called a scaling factor or an ecosystem scaling factor.

[0033] The MPLA coefficients are obtained by using Figure 1 The loss partitioning model for the transmitter and receiver shown is derived as Figure 2 The linear model (i.e., linear fit curve) shown is then calculated from its slope and intercept.

[0034] The scaling factors are defined as and Here, the superscripts GG, TG, GR, and TR are used to distinguish between various transmitter-receiver pairs. Specifically, GG indicates that the transmitter is the reference transmitter (Ref.PTx(TPT)) specified in the Qi standard, and the receiver is also the reference receiver (Ref.PRx(TPR)) specified in the Qi standard. TG also indicates that the transmitter is a general (or unknown) transmitter (General PTx) and the receiver is a reference receiver (Ref.PRx(TPR)) specified in the Qi standard. GR also indicates that the transmitter is the reference transmitter (Ref.PTx(TPT)) specified in the Qi standard and the receiver is a general (or unknown) receiver (General PRx). Furthermore, TR indicates that the transmitter is a general (or unknown) transmitter (General PTx) and the receiver is also a general (or unknown) receiver (General PRx). The ultimate goal of the existing MPLA method is to derive results under TR conditions. The same applies to the improved MPLA method described below.

[0035] In the existing MPLA method, coil loss,Tx The linear model (refer to Figure 2 (a)) or P coil loss,Rx The linear model (refer to Figure 2 (b)) Compared with P FM The linear model (refer to Figure 2 (c)) shows a large deviation. Figure 3 This deviation is specifically shown. This is estimated in practical application FM This will lead to a large error, which directly leads to the performance degradation of the FOD method.

[0036] In the existing MPLA method, as mentioned above, the power loss P caused by the friendly metal FM by Here, the friendly metal may refer to the metal component contained in the receiver. According to the above relationship, in the existing MPLA method, P FM Only as function to estimate (here, I Tx is the transmitter side coil current), which is considered to be the cause of the deviation.

[0037] In the improved MPLA method proposed in the present invention, in addition to (or I Tx), the distance between the transmitter and receiver (z or z-distance) and the rectified voltage of the receiver (V RECT ) can also be used as a method for estimating P FM variables come into play.

[0038] First, let's examine the effect of z-distance on P FM The effect is that as the z-distance increases, the leakage flux increases and interacts with a larger area of friendly metal. In this phenomenon, at the same I Tx Under these conditions, z-distance will inevitably lead to P FM changes.

[0039] Next, let’s examine V RECT P FM The impact of V RECT in I RECT A certain range of I may change instantaneously (for example, from 12V to 14V), which will cause I M discontinuity. M exist Figure 1 The loss partitioning model shown corresponds to the transmitter side coil current I Tx and the receiver side coil current I Rx The current added together. Since I M P FM The effect of V RECT The change of P FM discontinuity.

[0040] According to this physical reason analysis, z-distance and V RECT with I Tx It must be P FM Therefore, the existing MPLA method does not consider the z-distance and V RECT As P FM Compared with the variables of V, in the improved MPLA method proposed in the present invention, the z-distance and V RECT At least one of them is P FM variables.

[0041] Improved MPLA method

[0042] According to one embodiment of the present invention, the transmitter and receiver may include a basic structure for wireless charging using magnetic induction, such as a coil module. To apply MPP, the transmitter may also include a magnet. Furthermore, the receiver may include a metal-friendly metal. Figures 4 to 7 shown.

[0043] Specifically, in Figure 4 (a) and (b) show the perspective view and exploded perspective view of the reference transmitter (Ref.PTx(TPT)) specified in the Qi standard, respectively. Figure 4 As shown, the transmitter may include a coil (410), a magnet (420), a lower enclosure (430), an upper enclosure (440), etc. Here, the coil (410) may be configured to operate based on the MPP, and the magnet (420) may be formed to at least partially surround the coil (410).

[0044] And, in Figure 5 (a) and (b) show the plan view and stereo view of a general (or unknown) transmitter (General PTx) respectively. Unlike the stereo view, the plan view shows a prototype, not a model. Figure 5 As shown, the transmitter may include a coil (510), a magnet (520), a ferrite (530), a bracket (540), etc. Specifically, the coil (510) may be composed of a coil (511) arranged at the top and two coils (512, 513) arranged at the bottom, and the coil (511) arranged at the top may be configured to operate based on the MPP. Furthermore, the magnet (520) may be formed in a form that at least partially surrounds the coil (511) arranged at the top. For example, the magnet (520) is basically circular, but may also be formed in a form that alternates between arc shapes with a central angle of 150 degrees. Furthermore, the bracket (540) may be formed of aluminum. On the other hand, in the transmitter, the distance from the coil (511) arranged at the top to the upper surface of the transmitter may be 1.2 mm, and the distance from the magnet (520) to the upper surface of the transmitter may be 0.9 mm.

[0045] And, in Figure 6 (a) and (b) show a perspective view and an exploded perspective view of the reference receiver (Ref.PRx(TPR)) specified in the Qi standard, respectively. Figure 6As shown, the receiver may include a coil (610), a magnet (620), a lower housing (630), a support plate (640), and a friendly metal (650). Here, the coil (610) can operate based on the MPP, and the magnet (620) can be formed to at least partially surround the coil (610). Furthermore, the thickness of the friendly metal (650) can be 4.3 mm.

[0046] And, in Figure 7 (a) and (b) show a perspective view and an exploded perspective view of a general (or unknown) receiver (Gene al PRx) respectively. Figure 7 As shown, the receiver may include a coil (710), a magnet (720), a lower housing (730), a support plate (740), a friendly metal (750), etc. Here, the coil (710) can work based on MPP, and the magnet (720) can be formed to at least partially surround the coil (710). In addition, the thickness of the friendly metal (750) can be 0.7 mm. The thinner the thickness of the friendly metal, the greater the Open-air R and the smaller the Open-air Q, which is similar to the Figure 6 The receiver shown is compared to Figure 7 The thickness of the friendly metal of the receiver shown can be thinner. Figure 6 The receiver shown is compared to Figure 7 The components of the receivers shown may be identical to one another except for the thickness of the friendly metal.

[0047] According to one embodiment of the present invention, in the first and second embodiments described below, the transmitter and receiver pair can be selected based on the conditions related to the transmitter and receiver pair. Figures 4 to 7 The conditions related to the transmitter and receiver pairs required for executing the simulation in each embodiment will be described later.

[0048] On the other hand, according to one embodiment of the present invention, each of the transmitter and receiver may include a structure for computational processing (not shown). This structure can be referred to as a control circuit and may be formed from structures such as a processor and memory. Furthermore, this structure may be configured as a functional module. For example, the structure for computational processing may be configured as a module referred to as an acquisition unit or an estimation management unit in the transmitter and receiver, respectively. These functional modules can be understood as being included in the aforementioned control circuit. The following describes the improved MPLA method, focusing on these functional modules.

[0049] According to an embodiment of the present invention, when the transmitter performs the improved MPLA method, the obtaining unit can obtain the distance (z-dis tanc e) between the transmitter and the receiver and the rectified voltage (V RECT ), the estimation management unit can estimate the power loss (P FM ).

[0050] Furthermore, according to an embodiment of the present invention, when the receiver performs the improved MPLA method, the obtaining unit can obtain the z-distance between the transmitter and the receiver and the rectified voltage (V RECT ) at least one of the related information, the estimation management unit can refer to the obtained information to make the power loss (P FM ) can be estimated.

[0051] According to an embodiment of the present invention, the improved MPLA method executed by the functional modules can also be described as being executed by the transmitter or receiver itself, or by each control circuit included in the transmitter or receiver.

[0052] The improved MPLA method is divided into an embodiment in which the method is implemented in a manner dependent on the z-distance (hereinafter referred to as the "first embodiment") and an embodiment in which the method is implemented in a manner dependent on the z-distance and V. RECT On the other hand, the improved MPLA method is implemented in a manner that depends on V RECT The embodiment implemented in this manner (hereinafter referred to as the "third embodiment") can be easily derived from the first and second embodiments, so a detailed description is omitted. Of course, the third embodiment should also be understood as being included in the improved MPLA method proposed in this invention. Meanwhile, while the following embodiments are primarily described using a transmitter or receiver, it should be noted that the aforementioned control circuit or functional module could also be primarily described.

[0053] Example 1: Improved MPLA method depending on z-distance

[0054] In this embodiment, the following scheme is described: V RECT Fixed to 14 V, the transmitter and receiver pair simulated the existing MPLA method and the improved MPLA method under the conditions corresponding to TG and compared and evaluated their performances. Then, the improved MPLA method was implemented in the transmitter and receiver.

[0055] On the other hand, in addition to the above conditions, RECT with I RECTSimulations were performed with load powers defined by the product of and at 10 W, 12.5 W, and 15 W. Furthermore, simulations were performed with the transmitter at (0, 0, 0) in a three-dimensional orthogonal coordinate system, and the receiver at (0, 0, 0), (0, 0, 2), (2, 0, 0), and (2, 0, 2). Here, omitting the y coordinate in the receiver coordinates would also represent simulations performed at (0, 0), (0, 2), (2, 0), and (2, 2).

[0056] According to one embodiment of the present invention, Figure 8 As shown, the existing MPLA method does not consider the z-distance and derives P FM The linear model, but as Figure 9 As shown, the improved MPLA method can derive multiple P FM The z-distance is basically 0mm or 2mm, so in Figure 9 Two linear models were derived in Figure 10 , and summarize them in a chart.

[0057] According to an embodiment of the present invention, in the improved MPLA method, according to the z-distance, the α in the MPLA coefficient can be FM and α FM,D C is represented by and or and exist Figure 10 The MPLA coefficient α in the existing MPLA method is FM and α FM,DC are calculated as α FM =0.1682 and α FM,DC =0.4632. And, the MPLA coefficient in the improved MPLA method is and are calculated as and and are calculated as and

[0058] According to one embodiment of the present invention, in the improved MPLA method, for P FM , when the z-distance is 0mm, it can be derived When the z-distance is 2 mm, the relationship can be derived as If we summarize it, we can estimate P in the improved MPLA method depending on the z-distance. FM The relationship is as follows:

[0059] According to an embodiment of the present invention, if the existing MPLA method and the improved MPLA method are examined from the perspective of RMSE, they are as shown in Table 1. The unit is mW.

[0060] [Table 1]

[0061] z-distance(mm) Existing MPLA methods Improved MPLA method 0 82 55 2 77 47 All 80 51

[0062] According to one embodiment of the present invention, it has been verified that, in the improved MPLA method, when the z-distance is 0 mm, the performance advantage from the RMSE perspective is approximately 32.6% higher than that of the existing MPLA method; when the z-distance is 2 mm, the performance advantage from the RMSE perspective is approximately 39.4% higher than that of the existing MPLA method; and the overall performance advantage from the RMSE perspective is approximately 5.7% higher than that of the existing MPLA method.

[0063] According to an embodiment of the present invention, two approaches are conceivable for implementing the z-distance-dependent improved MPLA method in the transmitter and receiver.

[0064] First, the first solution is described.

[0065] First, the transmitter can store E 0xg and E 1xg , the receiver can store V RECT , α 0rx , α 1rx and α kth The receiver can use the XID packet to RECT , α 0rx , α 1rx and α kth Transmitted to the transmitter. The transmitter can use the stored E 0xg 、E 1xg 、V RECT , α 0rx , α 1rx and α kth and the measured V inv and V CTX_PP Estimated coupling coefficient (k est ). Used to estimate k est The relationship is as follows On the other hand, E {a]{b}{c}It can be called an eigen coefficient. Here, {a} can correspond to 0 or 1, 0 can refer to the slope of the linear model, and 1 can refer to the y-intercept of the linear model. In addition, {b} can correspond to g or x, g can refer to the reference transmitter (Ref.PTx(TPT)) specified in the Qi standard, and x can refer to the general (or unknown) transmitter (General PTx). In addition, {c} can correspond to g or y, g can refer to the reference receiver (Ref.PRx(TPR)) specified in the Qi standard, and x can refer to the general (or unknown) receiver (General PRx).

[0066] Then, the transmitter can use the KEST data packet to send k est At this time, the transmitter and receiver can respectively est The current coupling condition is determined by comparing it with the reference value. Here, the reference value can be 0.81×α kth .

[0067] Then, the transmitter may store a scaling factor that depends on the z-distance, and the receiver may store an MPLA coefficient that depends on the z-distance. Specifically, the transmitter may store g corresponding to the scaling factor. coil，Rx 、 and The receiver can store the g corresponding to the scale factor coil，Tx and corresponding to the MPLA coefficients and Here, and They are defined as and In other words, the transmitter can store a scaling factor that depends on the z-distance and The receiver can store MPLA coefficients that depend on the z-distance and

[0068] Next, when the determined coupling state corresponds to the first level (or higher level) (ie, k est 0.81×α kth In the above case), the transmitter can select the stored scaling factor and As a tool for estimating P FM The scaling factor of g is converted to coil，RxThe receiver can also transmit the g corresponding to the stored scale factor using the PLA data packet. coil，Rx and the stored MPLA coefficients and According to the scaling factor selected by the transmitter or the MPLA coefficient transmitted by the receiver, the k est To determine the z-distance, specifically, when k est 0.81×α kth If it is larger than 0 mm, it can be determined as 0 mm.

[0069] Alternatively, in the case where the determined coupling state corresponds to the second level (or lower level) (ie, k est Less than 0.81×α kth In the case of and As a tool for estimating P FM The scaling factor of g is converted to coil，Rx The receiver can also transmit the g corresponding to the stored scale factor using the PLA data packet. coil，Tx and the stored MPLA coefficients and According to the scaling factor selected by the transmitter or the MPLA coefficient transmitted by the receiver, the k est To determine the z-distance, specifically, when k est Less than 0.81×α kth When , it can be decided to be 2mm.

[0070] Then, the transmitter can estimate P by referring to the selected scale factor and the transmitted MPLA coefficient (ie, the information obtained about the z-distance). FM This can also be explained as the receiver making P FM It is estimated by the transmitter. Here, P FM Can be based on On the other hand, in addition to estimating P FM In addition, P can also be estimated coil loss，Tx , the receiver can estimate P coil loss，Rx .

[0071] Next, the second solution is described.

[0072] First, the transmitter can store E 0xg and E 1xg , the receiver can store VRECT , α 0rx , α 1rx and α kth The receiver can use the XID packet to RECT , α 0rx , α 1rx and α kth Transmitted to the transmitter. The transmitter can use the stored E 0xg 、E 1xg 、V RECT , α 0rx , α 1rx and α kth and the measured V inv and V CTX_PP Estimated coupling coefficient (k est ). Used to estimate k est The relationship is as follows: On the other hand, E {a}{b}{c} It can be called a characteristic coefficient. Here, {a} can correspond to 0 or 1, 0 can refer to the slope of the linear model, and 1 can refer to the y-intercept of the linear model. In addition, {b} can correspond to g or x, g can refer to the reference transmitter (Ref.PTx(TPT)) specified in the Qi standard, and x can refer to the general (or unknown) transmitter (General PTx). In addition, {c} can correspond to g or y, g can refer to the reference receiver (Ref.PRx(TPR)) specified in the Qi standard, and x can refer to the general (or unknown) receiver (General PRx).

[0073] Then, the transmitter and receiver can be est The current coupling condition is determined by comparing it with the reference value. Here, the reference value can be 0.81×α kth The transmitter can use the KEST data packet (depending on the situation, the KEST data packet transmitted from the transmitter to the receiver can also be called the first data packet) to send k est and k est Specifically, in the case where the determined coupling state corresponds to the first level (or higher level) (i.e., k est 0.81×α kth In the above case), the transmitter can use 0 as the est The corresponding information is allocated to the reserved bit of the KEST packet. In addition, when the determined coupling state corresponds to the second level (or lower level) (i.e., k est Less than 0.81×α kth In the case of k estOn the other hand, the KEST data packet may be composed of 3 bytes, wherein the bit sequence b7 to b4 of the second byte (B1) may correspond to the reserved bits.

[0074] Then, the transmitter may store a scaling factor that depends on the z-distance, and the receiver may store an MPLA coefficient that depends on the z-distance. Specifically, the transmitter may store g corresponding to the scaling factor. coil，Rx 、 and The receiver can store the g corresponding to the scale factor coil，Tx and corresponding to the MPLA coefficients and Here, and They can be defined as and In other words, the transmitter can store a scaling factor that depends on the z-distance and The receiver can store MPLA coefficients that depend on the z-distance and

[0075] Next, in the case where the information allocated to the reserved bit corresponds to 0 (ie, the case where the determined coupling state corresponds to the first level (or higher level) or k est 0.81×α kth In the above case), the transmitter can select the stored scaling factor and As a tool for estimating P FM The scaling factor of g is converted to coil,Rx The receiver can also transmit the g corresponding to the stored scale factor using the PLA data packet. coil,Tx and the stored MPLA coefficients and According to the scaling factor selected by the transmitter or the MPLA coefficient transmitted by the receiver, the k est To determine the z-distance, specifically, when k est 0.81×α kth If it is larger than 0 mm, it can be determined as 0 mm.

[0076] Alternatively, in the case where the information allocated to the reserved bit corresponds to 1 (ie, the determined coupling state corresponds to the second level (or lower level) or k est Less than 0.81×α kthIn the case of and As a tool for estimating P FM The scaling factor of g is converted to coil，Rx The receiver can also transmit the g corresponding to the stored scale factor using the PLA data packet. coil，Tx and the stored MPLA coefficients and According to the scaling factor selected by the transmitter or the MPLA coefficient transmitted by the receiver, the k est To determine the z-distance, specifically, when k est Less than 0.81×α kth When , it can be decided to be 2mm.

[0077] The transmitter can then use the selected scaling factor and the transmitted MPLA coefficients (i.e., the information obtained about the z-distance) to estimate P FM This can also be explained as the receiver making P FM It is estimated by the transmitter. Here, P FM Can be based on On the other hand, in addition to estimating P FM In addition, P can also be estimated coil loss,Tx , the receiver can estimate P coilloss，Rx .

[0078] Second embodiment: depending on z-distance and V RECT Improved MPLA method

[0079] In this embodiment, the following scheme is described: after simulating the existing MPLA method and the improved MPLA method in a transmitter and a receiver pair under conditions corresponding to TR and comparing and evaluating their performances, the improved MPLA method is implemented in the transmitter and the receiver.

[0080] On the other hand, in addition to the above conditions, RECT with I RECT The simulation was performed under the conditions of load powers of 2.5W, 5W, 7.5W, 10W, 12.5W, and 15W, which are defined by the product of V RECT For 12V, 10W, 12.5W and 15W are V RECTThe voltage is 14 V. Furthermore, simulations were performed with the transmitter at (0, 0, 0) in the three-dimensional orthogonal coordinate system and the receiver at (0, 0, 0), (0, 0, 2), (2, 0, 0), and (2, 0, 2). Here, omitting the y coordinate in the receiver coordinates would also represent simulations performed at (0, 0), (0, 2), (2, 0), and (2, 2).

[0081] like Figure 11 As shown, the existing MPLA method does not consider the z-distance and V under GG conditions, TG conditions, and GR conditions. RECT And derived P FM The MPLA coefficients under various conditions are shown in Table 2.

[0082] [Table 2]

[0083] <![CDATA[b coil ]]> <![CDATA[m coil ]]> <![CDATA[a FM ]]> <![CDATA[a FM,DC ]]> GG 0.4649 0.4939 0.0796 0.1667 TG 0.3661 0.4939 0.1805 0.3861 GR 0.4650 0.4385 0.0911 0.1701

[0084] Furthermore, the scaling factors under each condition are shown in Table 3.

[0085] [Table 3]

[0086] <![CDATA[g coil,Tx ]]> <![CDATA[g coil,Rx ]]> <![CDATA[g FM ]]> <![CDATA[g FM,DC <!-- 9 -->]]> 1.000 1.000 2.2676 2.3161

[0087] Under TR conditions, in the existing MPLA method, such as Calculate P as shown coil loss，Tx The estimated value of Calculate P as shown coil loss，Rx Furthermore, under TR conditions, in the existing MPLA method, such as Calculate P as shown FM Estimated value of .

[0088] exist Figure 12 The P values derived by the existing MPLA method under TR conditions are shown in FIG. FM The model shown by the dotted line (hereinafter referred to as model (a)) is the P derived without applying the scaling factor. FM A linear model, in which case P FM The estimated values are as follows: The model shown by the dashed line (hereinafter referred to as the (b) model) is an example of a V RECT The model is derived for the proportionality factor at 14 V. In this case, P FM The estimated values are as follows: Furthermore, the model shown by the solid line (hereinafter referred to as the (c) model) is an application of V RECT The model is derived for the scaling factor under 12V to 14V conditions. In this case, P FM The estimated values are as follows:

[0089] According to one embodiment of the present invention, if we examine the RMSE Figure 12 The three models shown are shown in Table 4. The unit is mW.

[0090] [Table 4]

[0091] (a) Model (b) Model (c) Model RMSE 83.8 87.3 84.5

[0092] According to one embodiment of the present invention, the existing MPLA method does not consider the z-distance and V RECT And derived P FM However, in the improved MPLA method, as Figure 13 As shown, according to z-distance and V RECT Export multiple P FM Linear model. z-distance is basically 0mm or 2mm, V RECT Basically it is 12V or 14V, so in Figure 13 In , four linear models are shown for each condition on a transmitter and receiver pair. Figure 13 GG conditions, TG conditions, and GR conditions are shown in FIG.

[0093] According to one embodiment of the present invention, V RECT The MPLA coefficient under the condition of 12V is shown in Table 5.

[0094] [Table 5]

[0095]

[0096] Furthermore, according to one embodiment of the present invention, V RECT The MPLA coefficient under the condition of 14V is shown in Table 6.

[0097] [Table 6]

[0098] Furthermore, according to one embodiment of the present invention, V RECT The proportional factors under the condition of 12V are shown in Table 7.

[0099] [Table 7]

[0100] Furthermore, according to one embodiment of the present invention, VRECT The proportional factors under the condition of 14V are shown in Table 8.

[0101] [Table 8]

[0102] According to one embodiment of the present invention, the improved MPLA method can estimate the value of the Z-distance and V under TR conditions. RECT P FM .

[0103] Specifically, when the z-distance is 0 mm and V RECT For 12V, you can Calculate P as shown FM Estimated value of .

[0104] And, when the z-distance is 2mm and V RECT For 12V, if Calculate P as shown FM Estimated value of .

[0105] And, when z-distance is 0mm and V RECT When the voltage is 14V, Calculate P as shown FM Estimated value of .

[0106] And, when the z-distance is 2mm and V RECT When the voltage is 14V, Calculate P as shown FM Estimated value of .

[0107] Here, the scaling factor and They are defined as and

[0108] exist Figure 14 The P values derived by the improved MPLA method under TR conditions are shown in FIG. FM A linear model of . Figure 14 The model shown by the dotted line and the model shown by the solid line are the (b) model and (c) model in the existing MPLA method respectively. Figure 14 The model shown by the thick solid line is derived from the improved MP LA method. FM The linear model is as follows:

[0109] According to one embodiment of the present invention, if we examine the RMSE Figure 14 The three models shown are shown in Table 9. The unit is mW.

[0110] [Table 9]

[0111] (b) Model of the existing MPLA method (c) Model of the existing MPLA method Model based on the improved MPLA method RMSE 87.3 84.5 60.9

[0112] According to one embodiment of the present invention, it has been verified that in the model based on the improved MPLA method, the performance advantage from the RMSE perspective is approximately 30.2% higher than that of the (b) model of the existing MPLA method, and the performance advantage from the RMSE perspective is approximately 27.9% higher than that of the (c) model of the existing MPLA method.

[0113] According to one embodiment of the present invention, the transmitter and receiver are implemented based on the z-distance and V RECT The scheme of the improved MPLA method is as follows.

[0114] First, the transmitter can store E 0xg and E 1xg , the receiver can store V RECT , α 0rx , α 1rx and α kth The receiver can use the XID packet to RECT , α 0rx , α 1rx and a kth Transmitted to the transmitter. The transmitter can use the stored E 0xg 、E 1xg 、V RECT , α 0rx , α 1rx and α kth and the measured V inv and V CTX_PP To estimate the coupling coefficient (k est ). Used to estimate k est The relationship is as follows: On the other hand, E {a}{b}{c} It can be called a characteristic coefficient. Here, {a} can correspond to 0 or 1, 0 can refer to the slope of the linear model, and 1 can refer to the y-intercept of the linear model. In addition, {b} can correspond to g or x, g can refer to the reference transmitter (Ref.PTx(TPT)) specified in the Qi standard, and x can refer to the general (or unknown) transmitter (General PTx). In addition, {c} can correspond to g or y, g can refer to the reference receiver (Ref.PRx(TPR)) specified in the Qi standard, and x can refer to the general (or unknown) receiver (General PRx).

[0115] Then, the transmitter can use the KEST data packet to send k est At this time, the transmitter and receiver can respectively est The current coupling state is determined by comparing it with the reference value. Here, the reference value can be 0.81×α kth .

[0116] Then, the transmitter can store the information that depends on the z-distance and V RECT The receiver can store a scaling factor that depends on the z-distance and V RECT Specifically, the transmitter may store the MPLA coefficient corresponding to the scale factor g coil,Rx 、 and The receiver can store the g corresponding to the scale factor coil,Tx and corresponding to the MPLA coefficients and Here, the brackets can be understood as a group. In other words, the transmitter can store the z-distance and V RECT The scaling factor The receiver can store information that depends on the z-distance and V RECT MPLA coefficient

[0117] The transmitter can then use the PLAP packet to store the g in the scale factor coil，Rx The receiver can transmit the g corresponding to the stored scale factor using a PLAP data packet (depending on the situation, the PLAP data packet transmitted from the receiver to the transmitter can also be called a second data packet). coil，Tx The receiver transmits all stored MPLA coefficients to the transmitter. In this case, when transmitting the MPLA coefficients to the transmitter, the receiver may set the PLAP data packet to be different for each MPLA coefficient (or group of MPLA coefficients) and transmit them. Specifically, the PLAP data packet may be composed of 7 bytes, wherein the second byte (B1) and the third byte (B2) may be allocated corresponding to The fourth byte (B3) and the fifth byte (B4) can be assigned corresponding The sixth byte (B5) and the seventh byte (B6) can be assigned to correspond to g coil，TxHere, the bit sequence b7 to b0 of the first byte (B0) of the PLAP data packet may correspond to a reserved bit, to which the reserved bit may be assigned a bit suitable for and z-distance and V RECT Here, when the z-distance is 0 mm, the information corresponding to the z-distance condition may correspond to 0, and when the z-distance is 2 mm, the information corresponding to the z-distance condition may correspond to 1. RECT For 12V, with V RECT The information corresponding to the condition can correspond to 0, in V RECT For 14V, with V RECT The information corresponding to the condition can correspond to 1, if V RECT can become greater than 14V, then with V RECT The information corresponding to the condition can correspond to a value greater than 1.

[0118] Then, if the transmitter receives the scale factor and the MPLA coefficient from the receiver, the transmitter may store the g corresponding to the scale factor. coil，Rx and g coil，Tx , as a set of scale factors and MPLA coefficients, we can store and On the other hand, the receiver can use the PLA data packet (depending on the situation, the PLA data packet transmitted from the receiver to the transmitter can also be called the third data packet) to transmit the data packet with V RECT The corresponding information is transmitted to the receiver. RECT The corresponding information is used to assist in estimating P FM While utilizing the information of the selection of the coefficients (specifically, the set of the scale factor and the MPLA coefficient), in V RECT In the case of 12V, it can correspond to 0, in V RECT When it is 14V, it can correspond to 1. If V RECT can become greater than 14V, then it can correspond to a value greater than 1. The receiver can be RECT The corresponding information is assigned to the reserved bits of the PLA data packet. The PLA data packet may consist of 5 bytes, wherein the bit sequence b4 to b0 of the first byte (B0) may correspond to the reserved bits.

[0119] The transmitter may then select a set of scale factors and MPLA coefficients (ie, For example, in the case where the determined coupling state corresponds to the first level (or higher level) (i.e., k est 0.81×α kth above) and the information assigned to the reserved bit corresponds to 0 (ie, V RECT For 12V), the transmitter can select from the set of scale factors and MPLA coefficients As a tool for estimating P FM As another example, in the case where the determined coupling state corresponds to the second level (or lower level) (i.e., k est Less than 0.81×α kth The case where the information assigned to the reserved bit corresponds to 1 (i.e., V RECT For 14V), the transmitter can select from the set of scale factors and MPLA coefficients As a tool for estimating P FM Here, according to the choice of transmitter, it can be based on k est To determine the z-distance, specifically, when k est 0.81×α kth When it is above, it can be determined to be 0mm. When k est Less than 0.81×α kth When , it can be decided to be 2mm.

[0120] The transmitter can then refer to the selected set of scale factors and MPLA coefficients (ie, the values for z-distance and V RECT The information obtained) estimates P FM This can also be explained as the receiver making P FM It is estimated by the transmitter. Here, P FM Can be based on On the other hand, in addition to estimating P FM In addition, P can also be estimated coil loss，Tx , the receiver can estimate P coil loss，Rx .

[0121] The present invention has been described above using specific matters such as specific constituent elements and limited embodiments and drawings, but this is only provided to help a more comprehensive understanding of the present invention. The present invention is not limited to the above-mentioned embodiments. Anyone with ordinary knowledge in the technical field to which the present invention belongs can make various modifications and changes based on such descriptions.

[0122] Therefore, the concept of the present invention should not be limited to the above-described embodiments, and all scopes equivalent to or modified by the claims described below fall within the scope of the concept of the present invention.

Claims

1. A method for estimating power loss, comprising the following steps: a step of obtaining information related to at least one of a spacing between the wireless power transmitter and the wireless power receiver and a rectified voltage of the wireless power receiver; and The step of estimating the power loss caused by the friendly metal with reference to the information obtained.

2. The method according to claim 1, wherein At least one of the interval and the rectified voltage functions as a variable for estimating the power loss.

3. The method according to claim 1, wherein The interval is determined according to the coupling coefficient.

4. The method according to claim 3, wherein: When the coupling coefficient is equal to or greater than a reference value, the interval is determined to be a first value, and when the coupling coefficient is less than the reference value, the interval is determined to be a second value.

5. The method according to claim 3, wherein The first data packet transmitted to the wireless power receiver includes information corresponding to the coupling coefficient.

6. The method according to claim 1, wherein The second data packet transmitted from the wireless power receiver includes coefficients for estimating the power loss and information corresponding to conditions applicable to the coefficients.

7. The method according to claim 1, wherein The third data packet transmitted from the wireless power receiver includes information for assisting in selecting a coefficient used to estimate the power loss.

8. The method according to claim 1, wherein A coefficient for estimating the power loss is stored in the wireless power receiver, The coefficient depends on at least one of the interval and the rectified voltage.

9. A wireless power transmitter, comprising: an obtaining unit configured to obtain information related to at least one of a distance between the wireless power transmitter and the wireless power receiver and a rectified voltage of the wireless power receiver; and The estimation management department estimates the power loss caused by the friendly metal with reference to the obtained information.

10. The wireless power transmitter according to claim 9, wherein: At least one of the interval and the rectified voltage functions as a variable for estimating the power loss.

11. The wireless power transmitter according to claim 9, wherein: The interval is determined according to the coupling coefficient.

12. The wireless power transmitter according to claim 11, wherein: When the coupling coefficient is equal to or greater than a reference value, the interval is determined to be a first value, and when the coupling coefficient is less than the reference value, the interval is determined to be a second value.

13. The wireless power transmitter according to claim 11, wherein: The first data packet transmitted to the wireless power receiver includes information corresponding to the coupling coefficient.

14. The wireless power transmitter according to claim 9, wherein: The second data packet transmitted from the wireless power receiver includes coefficients for estimating the power loss and information corresponding to conditions applicable to the coefficients.

15. The wireless power transmitter according to claim 9, wherein: The third data packet transmitted from the wireless power receiver includes information for assisting in selecting a coefficient used to estimate the power loss.

16. The wireless power transmitter according to claim 9, wherein: A coefficient for estimating the power loss is stored in the wireless power receiver, The coefficient depends on at least one of the interval and the rectified voltage.

17. A method for estimating power loss, comprising the steps of: a step of obtaining information related to at least one of a spacing between the wireless power transmitter and the wireless power receiver and a rectified voltage of the wireless power receiver; and Referring to the information obtained, a step is provided to estimate the power loss caused by the friendly metal.

18. The method according to claim 17, wherein At least one of the interval and the rectified voltage functions as a variable for estimating the power loss.

19. The method according to claim 17, wherein The interval is determined according to the coupling coefficient.

20. The method according to claim 19, wherein When the coupling coefficient is equal to or greater than a reference value, the interval is determined to be a first value, and when the coupling coefficient is less than the reference value, the interval is determined to be a second value.

21. The method according to claim 19, wherein The first data packet transmitted from the wireless power transmitter includes information corresponding to the coupling coefficient.

22. The method according to claim 17, wherein The second data packet transmitted to the wireless power transmitter includes coefficients for estimating the power loss and information corresponding to conditions applicable to the coefficients.

23. The method according to claim 17, wherein The third data packet transmitted to the wireless power transmitter includes information for assisting in selecting coefficients used to estimate the power loss.

24. The method according to claim 17, wherein A coefficient for estimating the power loss is stored in the wireless power receiver, The coefficient depends on at least one of the interval and the rectified voltage.

25. A wireless power receiver comprising: an obtaining unit configured to obtain information related to at least one of a distance between the wireless power transmitter and the wireless power receiver and a rectified voltage of the wireless power receiver; and The estimation management section, referring to the obtained information, enables the power loss caused by the friendly metal to be estimated.

26. The wireless power receiver according to claim 25, wherein: At least one of the interval and the rectified voltage functions as a variable for estimating the power loss.

27. The wireless power receiver of claim 25, wherein: The interval is determined according to the coupling coefficient.

28. The wireless power receiver according to claim 27, wherein: When the coupling coefficient is equal to or greater than a reference value, the interval is determined to be a first value, and when the coupling coefficient is less than the reference value, the interval is determined to be a second value.

29. The wireless power receiver according to claim 27, wherein: The first data packet transmitted from the wireless power transmitter includes information corresponding to the coupling coefficient.

30. The wireless power receiver of claim 25, wherein: The second data packet transmitted to the wireless power transmitter includes coefficients for estimating the power loss and information corresponding to conditions applicable to the coefficients.

31. The wireless power receiver of claim 25, wherein: The third data packet transmitted to the wireless power transmitter includes information for assisting in selecting coefficients used to estimate the power loss.

32. The wireless power receiver of claim 25, wherein: A coefficient for estimating the power loss is stored in the wireless power receiver, The coefficient depends on at least one of the interval and the rectified voltage.

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