JP2020191730A - Non-contact power supply system and control method thereof - Google Patents

Abstract

To appropriately switch power transmission coils which transmit power to a power reception coil.SOLUTION: A non-contact power supply system has: a power supply device 100; and a power reception device 205 which is loaded on a moving body 200, and whose relative position fluctuates to the power supply device, in which power is supplied by non-contact from the power supply device to the power reception device. The power reception device comprises a power reception resonance circuit 210 which includes at least one power reception coil 212. The power supply device comprises: a plurality of segments Seg which have a power transmission resonance circuit 110 including at least one power transmission coil 112 for transmitting power to the power reception device via the power reception coil; and a controller 140 which controls operations of segments for continuing power transmission to the power reception device, segments for stopping the power transmission, and segments for starting the power transmission by comparing pieces of information regarding power to be supplied to the power transmission coil in segments for transmitting power to the power reception device.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a technique for supplying electric power to a mobile body in a non-contact manner.

In Patent Document 1, in a power feeding device that supplies electric power to a vehicle as a moving body traveling in a predetermined direction in a non-contact manner, power transmission coils are arranged in the direction in which the moving body travels, and the power transmitting coils for power transmission are arranged as the moving body. It is disclosed that power is continuously supplied by switching according to the movement of. Specifically, when even a part of the power receiving coil invades the coil surface of the power transmission coil, the power transmission coil is switched to transmit power by the intruded power transmission coil. Further, it is disclosed that by expanding the area of the coil surface of the power transmission coil in a direction other than a predetermined direction, a decrease in power feeding efficiency is suppressed when the traveling direction of the vehicle deviates.

Japanese Patent No. 6221460

However, in the above-mentioned power transmission coil switching method, the power transmission coil may be switched even when the power reception coil does not face the power transmission coil directly, so that the power received by the moving body is reduced and the movement is performed. There is a problem that the power required by the body is not satisfied and the power control of the moving body is adversely affected.

According to one embodiment of the present disclosure, the power receiving device (100) and the power receiving device (205) mounted on the moving body (200) and whose position relative to the power feeding device fluctuates are included. A non-contact power feeding system is provided in which power is supplied from the power feeding device to the power receiving device in a non-contact manner. In this non-contact power feeding system, the power receiving device includes a power receiving resonant circuit (210) including at least one power receiving coil (212). The power feeding device includes a plurality of segments (Seg) having a power transmission resonance circuit (110) including at least one power transmission coil (112) that transmits power to the power receiving device via the power receiving coil, and power to the power receiving device. By comparing the information about the power supplied to the power transmission coil in the power transmission segment, the segment that continues the power transmission to the power receiving device, the segment that stops the power transmission, and the segment that starts the power transmission A control device (140) for controlling the operation is provided.
According to this non-contact power supply system, by comparing information about the power supplied to the transmission coil in the segment that transmits power to the power receiving device, the segment that continues to transmit power to the power receiving device and the segment that stops transmission are stopped. It is possible to control the operation of the segment and the segment that starts power transmission. Thereby, for example, it is possible to appropriately switch between the segment for stopping power transmission and the segment for starting power transmission in a state where the power receiving coil faces the power transmission coil and faces the power transmission coil, and the power received by the power receiving device can be appropriately switched. Can be suppressed from decreasing.

According to another embodiment of the present disclosure, power is supplied from the power feeding device (100) to the power receiving device (205) mounted on the moving body (200) and whose position relative to the power feeding device changes. A method of controlling a contactless power supply system is provided. The power receiving device includes a power receiving resonant circuit (210) including at least one power receiving coil (212). The power feeding device includes a plurality of segments (Segs) having a power transmission resonant circuit (110) including at least one power transmission coil (112) that transmits power to the power receiving device via the power receiving coil. In the control method of the non-contact power supply system, the segment that continues to transmit electric power to the power receiving device and the segment that continues to transmit electric power to the power receiving device by comparing information about the electric power supplied to the power transmitting coil in the segment that transmits electric power to the power receiving device. It controls the operation of the segment that stops power transmission and the segment that starts power transmission.
According to the control method of this non-contact power supply system, by comparing the information about the power supplied to the transmission coil in the segment that transmits power to the power receiving device, the segment that continues to transmit power to the power receiving device and the transmission It is possible to control the operation of the segment that stops and the segment that starts power transmission. Thereby, for example, in a state where the power receiving coil faces the power transmission coil and faces the power transmission coil, the segment for stopping the power transmission and the segment for starting the power transmission can be appropriately switched, and the power received by the power receiving device can be appropriately switched. Can be suppressed from decreasing.

A block diagram showing the overall configuration of a contactless power supply system. A block diagram showing one segment of a power feeding device and a power receiving device. Explanatory drawing which shows an example of the positional relationship between a power feeding device and a power receiving device. Explanatory drawing which shows the amount of electric power fluctuation according to the position of the power receiving coil with respect to the power transmission coil. The explanatory view which shows the fluctuation of the received power when the 1st position of FIG. 4 is set as a switching position. The explanatory view which shows the fluctuation of the received power when the 2nd position of FIG. 4 is set as a switching position. Explanatory drawing which compares the current of the segment which stops power transmission and the current of a segment which continues power transmission. The explanatory view which shows an example of the switching timing determination processing. The explanatory view which shows another example of the switching timing determination processing. The explanatory view which shows an example of the positional relationship between the power feeding device and the power receiving device in the 2nd Embodiment. The explanatory view which shows an example of the positional relationship between the power feeding device and the power receiving device in the third embodiment. Explanatory drawing which compares and shows the current of the segment which stops power transmission and the current of a segment which starts power transmission. The explanatory view which shows an example of the switching timing correction processing. Explanatory drawing which shows a specific example of switching timing correction. The block diagram which shows the whole structure of the non-contact power supply system including the power supply device of another embodiment.

A. First Embodiment:
As shown in FIG. 1, the non-contact power feeding system includes a power feeding device 100 installed on the road RS and a power receiving device 205 mounted on a vehicle 200 traveling on the road RS as a moving body, and the vehicle 200 is running. It is a system capable of supplying electric power to the vehicle 200. The vehicle 200 is configured as, for example, an electric vehicle or a hybrid vehicle. In FIG. 1, the x-axis direction indicates the traveling direction of the vehicle 200, the y-axis direction indicates the width direction of the vehicle 200, and the z-axis direction indicates the vertically upward direction. The directions of the x, y, and z axes in other figures described later also show the same directions as in FIG.

The power supply device 100 includes a plurality of segment Segs, a power supply circuit 130 that supplies DC power to the plurality of segment Segs, and a control device 140 that controls the operation of the plurality of segment Segs. Each segment Seg includes a power transmission resonance circuit 110 and a power transmission circuit 120 that supplies AC power to the power transmission resonance circuit 110.

The power transmission resonance circuit 110 has a power transmission coil 112 installed on or in the road surface of the road RS, and a resonance capacitor (not shown). The power transmission coil 112 of each segment Seg is installed along the traveling direction of the vehicle 200 (also referred to as “extending direction of the road RS”).

The power transmission circuit 120 is a circuit that converts the DC power supplied from the power supply circuit 130 into high-frequency AC power and supplies it to the power transmission coil 112 of the power transmission resonance circuit 110. A specific configuration example of the power transmission circuit 120 will be described later. The power supply circuit 130 is a circuit that supplies DC power to the power transmission circuit 120. For example, the power supply circuit 130 is configured as an AC / DC converter circuit that rectifies the AC voltage of the external power supply and outputs a DC voltage.

Note that FIG. 1 shows four segments of the first segment Seg1 to the fourth segment Seg4 among the plurality of segment Segs, and the power receiving device described later above the power transmission coil 112 of the second segment Seg2. A state in which the power receiving coil 212 of 205 is located is shown as an example.

The control device 140 controls the operation of the power transmission circuit 120 of each segment Seg according to the position of the power reception coil 212 with respect to the power transmission coil 112, and controls the switching of the segment for which power is transmitted. The positional relationship of the power receiving coil 212 with respect to the power transmission coil 112 is estimated, for example, based on the measurement information DI of the current supplied from the power transmission circuit 120 to the power transmission coil 112 in each segment Seg. The control device 140 supplies the control information SD that controls the operating state to the power transmission circuit 120 of each segment Seg so that the power transmission circuit 120 of each segment Seg is in the operating state suitable for the estimated positional relationship. Note that FIG. 1 shows a state in which the measurement information DI1 to DI4 of the current supplied to each power transmission coil 112 from each power transmission circuit 120 of each of the first to fourth segments Seg1 to Seg4 is supplied to the control device 140. It is shown. Further, the state in which the control information SD1 to SD4 are supplied to each power transmission circuit 120 is shown. The control device 140 controls switching of segments for transmitting electric power. The segment switching operation under the control of the control device 140 will be described later.

The vehicle 200 includes a power receiving device 205, a main battery 230, a motor generator 240, an inverter circuit 250, a DC / DC converter circuit 260, an auxiliary battery 270, an auxiliary machine 280, and a control device 290. There is. The power receiving device 205 has a power receiving resonance circuit 210 and a power receiving circuit 220.

The power receiving resonance circuit 210 includes a power receiving coil 212 installed on the bottom surface of the vehicle 200 and a resonance capacitor (not shown), and receives AC power induced in the power receiving coil by an electromagnetic induction phenomenon between the power transmission resonance circuit 110. It is a device to obtain. The size of the coil surface of the power receiving coil 212 facing the power transmission coil 112 side and the size of the coil surface of the power transmission coil 112 facing the power receiving coil 212 side in the traveling direction are almost the same. The coil surface is a surface surrounded by loop-shaped wiring and functions as a loop-shaped coil, and in FIG. 1, it is basically a surface along the xy plane. The power receiving circuit 220 is a circuit that converts AC power output from the power receiving resonance circuit 210 into DC power. A specific configuration example of the power receiving circuit 220 will be described later. The DC power output from the power receiving circuit 220 can be used to charge the main battery 230 as a load. Further, the DC power output from the power receiving circuit 220 can also be used for charging the auxiliary battery 270, driving the motor generator 240, and driving the auxiliary machine 280.

The main battery 230 is a secondary battery that outputs DC power for driving the motor generator 240. The motor generator 240 operates as a three-phase AC motor and generates a driving force for traveling of the vehicle 200. The motor generator 240 operates as a generator when the vehicle 200 is decelerated, and generates three-phase AC power. When the motor generator 240 operates as a motor, the inverter circuit 250 converts the DC power of the main battery 230 into three-phase AC power to drive the motor generator 240. When the motor generator 240 operates as a generator, the inverter circuit 250 converts the three-phase AC power output by the motor generator 240 into DC power and supplies it to the main battery 230.

The DC / DC converter circuit 260 converts the DC voltage of the main battery 230 into a lower DC voltage and supplies it to the auxiliary battery 270 and the auxiliary 280. The auxiliary battery 270 is a secondary battery that outputs DC power for driving the auxiliary battery 280. The auxiliary machine 280 is a peripheral device such as an air conditioner or an electric power steering device.

The control device 290 controls each part in the vehicle 200. The control device 290 controls the power receiving circuit 220 to receive power when receiving non-contact power supply during traveling.

One segment Seg of the power feeding device 100 and the power receiving device 205 of the vehicle 200 are composed of, for example, the circuit shown in FIG. FIG. 2 shows, for example, a state in which power transmission is being performed between the second segment Seg2 and the power receiving device 205.

The power transmission resonance circuit 110 has a power transmission coil 112 and a resonance capacitor 116 connected in series. Like the power transmission resonance circuit 110, the power reception resonance circuit 210 also has a power reception coil 212 and a resonance capacitor 216 connected in series. A primary series secondary series capacitor system (also referred to as “SS system”) is applied to the power transmission resonance circuit 110 and the power reception resonance circuit 210. Further, a non-contact power feeding system of a single-phase power transmission side to a single-phase power reception side is applied, in which the power transmission side is composed of a single-phase power transmission coil 112 and the power reception side is composed of a single-phase power reception coil 212.

The transmission circuit 120 includes an inverter circuit 122 that converts DC power from the power supply circuit 130 into AC power, and a filter circuit 124 that reduces a high frequency component higher than the basic frequency component of the AC power to be transmitted. As the filter circuit 124, a filter circuit such as an imittance conversion circuit, a low-pass filter circuit, or a band-pass filter circuit is used. The filter circuit 124 can be omitted.

A current sensor SA for measuring the current flowing through the power transmission coil 112 is provided on one of the pair of wirings connecting the filter circuit 124 and the power transmission resonance circuit 110, and the result measured by the current sensor SA is used as measurement information DI2. It is supplied to the control device 140 (FIG. 1). Further, a voltage sensor SV for measuring the voltage applied to the power transmission coil 112 is provided between both ends of the power transmission coil 112, and the result measured by the voltage sensor SV is supplied to the control device 140 as measurement information DV2. ..

As will be described later, the control device 140 determines the operating conditions of the inverter circuit 122 of the segment Seg related to power transmission based on the measurement information DV and DI acquired in the segment Seg related to power transmission to the power receiving coil 212. Then, the control device 140 supplies the control information SD that controls the operating state of the inverter circuit 122 to the inverter circuit 122 of each segment Seg. The switching of the power transmission state of each segment Seg is executed depending on whether the inverter circuit 122 is in the operating state or the stopped state.

The power receiving circuit 220 is used for charging the main battery 230, a filter circuit 224 that reduces a frequency component higher than the basic frequency component of the received AC power, a rectifier circuit 226 that converts the AC power from the filter circuit 224 into DC power. It includes a DC / DC converter circuit 228 as a power conversion circuit that converts the power into a suitable DC voltage. Similar to the filter circuit 124, the filter circuit 224 also uses a filter circuit such as an imittance conversion circuit, a low-pass filter circuit, and a band-pass filter circuit. The filter circuit 224 can be omitted.

The following description is for the case where the vehicle 200 is traveling in the x direction, which is the traveling direction, and the power receiving coil 212 is passing over the power transmission coil 112-2 of the second segment Seg2, as shown in FIG. Will be described as an example. Further, it is assumed that the second segment Seg2 is in the power transmission continuous state, the first segment Seg1 is switched from the power transmission state to the power transmission stop state, and the third segment Seg3 is switched from the power transmission stop state to the power transmission state. Further, the position where this switching is performed is referred to as a "switching position".

As shown in FIG. 4, the amount of fluctuation of the electric power received by the power receiving device 205 changes depending on the position of the power receiving coil 212 in the traveling direction with respect to the second power transmitting coil 112-2. The amount of fluctuation is the smallest when the center position of the coil surface of the power receiving coil 212 coincides with the center position Pc of the coil surface of the power transmission coil 112-2. On the other hand, the center position of the coil surface of the power receiving coil 212 is the front side (also referred to as "back side") or the rear side ("front side") in the traveling direction from the center position Pc of the coil surface of the power transmission coil 112-2. The farther away it is (also called), the greater the fluctuation amount of the received power. In the following, the center position of the coil surface of the coil is also simply referred to as the "center position of the coil". Further, the fact that the center position of the power receiving coil 212 coincides with the center position Pc of the power transmission coil 112-2 corresponds to "the power receiving coil 212 faces the power transmission coil 112-2 directly". The “match” also includes a state in which the center position of the power receiving coil 212 is within the range R described below.

For example, as shown in FIG. 4, the first position Ps1 on the front side in the traveling direction of a certain range R indicating a range equal to or less than the allowable fluctuation amount Pla set in advance as the allowable value of the fluctuation amount of electric power is set as the switching position. In this case, as shown in FIG. 5, the fluctuation of the received power becomes large. The same applies when the position on the far side in the traveling direction of a certain range R is set as the switching position. On the other hand, if the second position Ps2 within a certain range R is set as the switching position, the fluctuation of the received power can be reduced as shown in FIG. The constant range R is a range from the position (Pc-R / 2) to the position (Pc + R / 2) in the traveling direction (see FIG. 4).

When the center position of the power receiving coil 212 is within a certain range R in the coil surface of the power transmission coil 112-2 in the traveling direction, the switching timing with that position as the switching position is determined, for example, as follows. It is done.

In the second segment Seg2 where the center position of the power receiving coil 212 is above the coil surface of its own power transmission coil 112-2 and power transmission is continued (see FIG. 3), the current I2 flowing through the power transmission coil 112-2 is , As shown in the lower part of FIG. 7, it changes according to the center position of the power receiving coil 212. That is, the center position of the power receiving coil 212 becomes larger as it approaches the range R on the front side in the traveling direction than the range R, and is the largest state in the range R, more specifically, the largest state in the center position Pc. It becomes. Further, the current I2 becomes smaller as the center position of the power receiving coil 212 deviates from the range R.

On the other hand, in the first segment Seg1 where the center position of the power receiving coil 212 moves away from the coil surface of its own power transmission coil 112-1 and power transmission is stopped (see FIG. 3), the current flowing through the power transmission coil 112-1 As shown in the upper part of FIG. 7, I1 decreases as the center position of the power receiving coil 212 in the traveling direction moves away. However, in order to explain the change in the current flowing through the power transmission coil 112-1, the current I1 shown in the upper part of FIG. 7 is an example of a case where the power transmission of the first segment Seg1 is kept in a continuous state without being stopped. It is shown.

Therefore, focusing on the current I2 of the second segment Seg2 where power transmission is continued and the current I1 of the first segment Seg1 where power transmission is stopped before that, comparing these, the center position of the power receiving coil 212 Can be estimated whether or not is in the position within the above range R. Then, at the timing when the center position of the power receiving coil 212 is at the switching position within the above range R, the first segment Seg1 is switched from the power transmission state to the stopped state, and the third segment Seg3 is switched from the stopped state to the power transmission state. Can be done.

The control device 140 can switch the operation of the first segment Seg1 for stopping the power transmission and the operation of the third segment Seg3 for stopping the power transmission by repeatedly executing the switching timing determination process shown in FIG. 8, for example. it can. First, the current I2 of the second segment Seg2 that continues power transmission and the current I1 of the first segment Seg1 that stops power transmission are measured (step S12). Then, it is determined whether or not the absolute value | I2-I1 | of the difference between the current I2 and the current I1 is larger than the threshold value Td (step S14). The threshold value Td is a value in which the central position of the power receiving coil 212 corresponds to the boundary of the range R of the coil surface of the power transmission coil 112-2, and is set in advance by actual measurement or the like.

In the case of | I2-I1 | ≦ Td (step S14: NO), it is estimated that the position of the power receiving coil 212 is not in the switching position within the range R, so the process returns to step S12 and the process is repeated. On the other hand, in the case of | I2-I1 |> Td (step S14: YES), it is estimated that the position of the power receiving coil 212 is at the switching position within the range R, so that the first segment Seg1 is stopped from the power transmission state. At the same time as switching to the state, the third segment Seg3 is switched from the stopped state to the power transmission state (step S16). Then, the process returns to step S12 and the process is repeated.

By repeating the above processing, the first segment Seg1 is switched from the power transmission state to the stopped state at the timing when the center position of the power receiving coil 212 is at the switching position within the range R of the second power transmission coil 112-2. At the same time, the third segment Seg3 can be switched from the stopped state to the power transmission state.

Further, for example, the control device 140 repeatedly executes the switching timing determination process shown in FIG. 9 to switch the operation of the first segment Seg1 for stopping the power transmission and the operation of the third segment Seg3 for stopping the power transmission. be able to. FIG. 9 is different in that the determination process of step S14 of FIG. 8 is replaced with the determination process of step S14b. In step S14b, it is determined whether or not the absolute value | I1 / I2 | of the ratio of the current I1 to the current I2 is larger than the threshold value Tr (step S14). The threshold value Tr is a value in which the central position of the power receiving coil 212 corresponds to the boundary of the range R of the coil surface of the power transmission coil 112-2, and is set in advance by actual measurement or the like.

In the case of | I1 / I2 | ≧ Tr (step S14b: NO), it is estimated that the position of the power receiving coil 212 is not in the switching position within the range R, so the process returns to step S12 and the process is repeated. On the other hand, in the case of | I1 / I2 | <Tr (step S14b: YES), it is estimated that the position of the power receiving coil 212 is at the switching position within the range R, so that the first segment Seg1 is stopped from the power transmission state. At the same time as switching to the state, the third segment Seg3 is switched from the stopped state to the power transmission state (step S16).

Also in the case of this processing, the first segment Seg1 is switched from the power transmission state to the stopped state at the timing when the center position of the power receiving coil 212 is at the switching position within the above range R of the second power transmission coil 112-2. The third segment Seg3 can be switched from the stopped state to the power transmission state.

In the switching timing determination process of FIGS. 8 and 9, in order to facilitate the explanation, the power receiving coil is in the state shown in FIG. 3, that is, above the coil surface of the power transmission coil 112-2 of the second segment Seg2. The case where the center position of the 212 is present has been described as an example, but the same applies when the center position of the power receiving coil 212 is on the coil surface of the power transmission coil 112 of another segment. For example, when power transmission of the third segment Seg3 is started, the third segment Seg3 is the second segment Seg2, the second segment Seg2 is the first segment Seg1, and the fourth segment Seg4 is the above. The same process may be executed as the third segment Seg3.

As described above, in the power supply device 100 of the non-contact power supply system, it is appropriate to switch between the segment for stopping power transmission and the segment for starting power transmission by comparing the currents supplied to the power transmission coil 112 of the segment Seg. It is possible to obtain a suitable timing and switch between a segment that starts power transmission and a segment that stops power transmission at the desired appropriate timing. As a result, power is effectively supplied from the segment where power transmission is continued, and the balance between the power that is no longer supplied from the segment where power transmission is stopped and the power supplied from the segment where power transmission is started is balanced. It will be possible to plan appropriately. As a result, it is possible to effectively suppress a decrease in the power received by the power receiving device 205 generated by switching the segments. Further, as described above, since the segment can be switched by comparing the current supplied to the power transmission coil 112 on the power supply device 100 side, the position information of the power reception coil 212 can be acquired by communication with the vehicle 200 or the like. It is not necessary, and it is possible to suppress a decrease in the power received, and it is possible to simplify the equipment configuration on the power supply device 100 side.

B. Second embodiment:
In the first embodiment, as described above (see FIG. 8 or 9), the current I2 of the second segment Seg2 in which power transmission is continued and the current I1 of the first segment Seg1 in which power transmission is stopped are compared. Therefore, it was determined whether or not the center position of the power receiving coil 212 was within the range R indicating the allowable switching position. However, the present invention is not limited to this, and for example, the following may be applied. The configuration of the non-contact power supply system of the second embodiment is the same as that of the non-contact power supply system of the first embodiment (see FIG. 1).

As shown in FIG. 10, when the power receiving coil 212 is located above the coil surface of the power transmission coil 112-1 (see FIG. 3) of the first segment Seg1 instead of the second segment Seg2, the power transmission coil 112 At the switching position Sp1 corresponding to -1, the power transmission of the 0th segment Seg0 (not shown in FIG. 3) is stopped, and the power transmission of the second segment Seg2 is started. At this switching position Sp1, the current flowing through the first segment Seg1 can be treated in the same manner as the current I2 of the second Seg2 at the switching position Sp2 corresponding to the power transmission coil 112-2 of the second segment Seg2. Therefore, the current I1c of the first segment Seg1 at the switching position Sp1 is measured and recorded. Then, by comparing the current I1c and the current I1, it is determined whether or not the center position of the power receiving coil 212 is within the range R indicating the allowable switching position in the transmission coil 112-2 of the second segment Seg2. You may try to do it. Even in this way, as in the first embodiment, the first segment Seg1 is transmitted at the timing when the center position of the power receiving coil 212 is at the switching position within the above range R of the second power transmission coil 112-2. The third segment Seg3 can be switched from the stopped state to the power transmission state while switching from the stopped state to the stopped state.

C. Third Embodiment:
In the third embodiment, as shown in FIG. 11, as described in the first embodiment, the position P2 in the traveling direction of the power transmission coil 112-2 of the second segment Seg2 is set as the switching position, and the power transmission segment is used. The correction of the switching timing will be described by taking the case of switching as an example. The configuration of the non-contact power supply system of the third embodiment is the same as that of the non-contact power supply system of the first embodiment (see FIG. 1).

As shown in the upper and lower stages of FIG. 12, when the switching position P2 coincides with the center position Pc of the power transmission coil 112-2, basically, the current I1 of the first segment Seg1 for stopping power transmission And the current I3 of the third segment Seg3 that starts power transmission is the same. On the other hand, as the switching position P2 shifts toward the front side in the traveling direction from the center position Pc and shifts toward the front side from the range R, the current I1 becomes larger and the current I3 becomes smaller. Further, as the switching position P2 shifts to the front side in the center position Pc traveling direction and shifts to the front side from the range R, the current I1 becomes smaller and the current I3 becomes larger. The current I1 in the upper part of FIG. 11 is shown as an example in a case where the power transmission of the first segment Seg1 is in a continuous state without switching in order to explain the state of change in the current flowing through the power transmission coil 112-1. There is. Similarly, the current I3 in the lower part of FIG. 11 is also rarely used as an example in which the power transmission of the third segment Seg3 is in a continuous state without switching in order to explain the state of change in the current flowing through the power transmission coil 112-3. ing.

Therefore, as described below, according to the comparison result of comparing the current I1 and the current I3, the power transmission coil 112- of the segment Seg3 in which the center position of the power receiving coil 212 is next to the switching timing at the switching position P2. The switching timing indicating the switching position when the position is above 3 may be corrected. In the following, the switching timing indicating the switching position when the center position of the power receiving coil 212 is above the power transmission coil 112-3 of the next segment Seg3 is, for example, "cutting timing of the next segment Seg3". It may be described in.

The control device 140 (see FIG. 1) can determine the switching position after the switching position P2 by repeatedly executing the switching timing correction process shown in FIG. 13, for example. First, the current I1 of the first segment Seg1 immediately before the power transmission is stopped due to the switching at the switching position P2 is measured (step S21), and the current I3 of the third segment Seg3 immediately after the start of power transmission is measured (step S22). Then, the difference [| I1 |-| I3 |] between the absolute value | I1 | of the current I1 and the absolute value | I3 | of the current I3 is −S or more and S or less (S is a constant positive value). Whether or not it is determined (step S23). Further, when −S ≦ | I1 | − | I3 | ≦ S is not satisfied (step S23: NO), it is determined whether or not the difference [| I1 | − | I3 |] is larger than S (step S24). .. The range of −S or more and S or less indicates the range of the difference [| I1 |-| I3 |] corresponding to the range R (see FIG. 4) allowed as the switching position P2, and the value of S is measured by actual measurement or the like. It is set in advance.

Therefore, in the case of −S ≦ | I1 | − | I3 | ≦ S (step S23: YES), it is estimated that the switching position P2 is within the range R. Therefore, in this case, the center position of the power receiving coil 212 is set to the same switching timing as the switching position P2 without correcting the switching timing indicating the switching position in the power transmission of the next segment Seg3 (step S25). Further, in the case of S << I1 |-| I3 | (step S23: NO and step S24: YES), the switching position P2 is behind the range R in the traveling direction (also referred to as "front side"). It is presumed that the position is shifted to. Therefore, in this case, the switching timing indicating the switching position of the next segment Seg is corrected to the front side in the traveling direction (step S26). Further, in the case of | I1 |-| I3 | <-S (step S23: NO and step S24: NO), the switching position P2 is closer to the traveling direction than the range R (also referred to as "rear side"). It is presumed that the position is shifted to. Therefore, in this case, the switching timing indicating the switching position of the next segment Seg is corrected to the back side in the traveling direction (step S27). Thereby, the switching timing of the segment Seg3 next to the switching position P2 can be corrected with respect to the switching timing corresponding to the switching position P2, and the switching position of the next segment Seg3 can be determined.

Then, after the processing of steps S25, S26, and S27, the process returns to step S21 and the processing is repeated. Thereby, the switching timing of each segment Seg after the switching position P2 can be sequentially corrected, and the switching position of each segment Seg after the switching position P2 can be determined.

In the switching timing correction process of FIG. 13, in order to facilitate the explanation, the center position of the power receiving coil 212 is located on the coil surface of the power transmission coil 112-2 of the second segment Seg2 in the state shown in FIG. An example has been described in which the switching position P2 is set to switch between the first and third segments Seg1 and Seg3. The same applies when the center position of the power receiving coil 212 is on the coil surface after the power transmission coil 112-3 of the third segment Seg3. For example, when the vehicle 200 moves and the power transmission of the third segment Seg3 is started, the segment Seg3 is designated as the second segment Seg2 and the second segment Seg2 is designated as the first segment Seg1. The same process may be executed by setting the segment Seg4 as the third segment Seg3.

Here, the correction of the switching timing in steps S26 and S27 can be performed, for example, as follows. As shown in FIG. 14, the vehicle speed at the switching position Pn (n is the segment number) is Vn, the distance between the power transmission coils 112 of each segment is d, and between the current switching position Pn and the next switching position Pn + 1. Let tn be the time interval for switching, and α be the correction value for the interval. In this case, the interval tn is expressed by the following equation (1). For example, the interval t2 from the switching position P2 to the next switching position P3 is represented by the following equation (2).
tun = tun-1 · (1 ± α) + (Vn-1-Vn) / d ... (1)
t2 = t1 · (1 ± α) + (V1-V2) / d ... (2)

As shown in the above equation (1), the correction in steps S26 and S27 can be performed by increasing or decreasing the interval tn to the switching position of the next segment with the correction value α. Specifically, in step S26, a correction value α is used to make a correction that decreases the interval nt (t2 in the example of FIG. 13), and in step S27, a correction value α is used to make a correction that increases the interval nt (t2 in the example of FIG. To do. The correction value α is a predetermined constant value. However, the correction value α is not limited to this, and the correction value α is the absolute value of the current of the segment to stop (current I1 in the example of FIG. 13) and the current of the segment to start (current I3 in the example of FIG. 13). The variable may be set according to the difference in absolute values ([| I1 |-| I3 |] in the example of FIG. 13).

Further, the correction of the switching timing in steps S26 and S27 can be performed as follows. That is, the threshold value Td used in the determination process of step S14 in FIG. 8 is corrected by the correction value αd as shown in the following equation (3), and the threshold value Tr used in the determination process in step S14b of FIG. 9 is lowered. As shown in the equation (4), the correction value αr may be used for correction.
Tdn = Tdn-1 · (1 ± αd) ... (3)
Trn = Trn-1 ・ (1 ± αr) ・ ・ ・ (4)
Note that Tdn and Trn are threshold values at the switching position Pn. Further, the correction values αd and αr may be constant values or variables as in the case of the correction values α.

D. Other embodiments:
(1) As shown in FIG. 1, the power supply device 100 of the non-contact power supply system of the above embodiment includes a configuration in which a power transmission circuit 120 whose power transmission operation is controlled by a control device 140 is provided for each segment Seg. Explained to. However, it is not limited to this. For example, it may be a non-contact power feeding system including the power feeding device 100C shown in FIG.

Unlike the power feeding device 100 (see FIG. 1), the power feeding device 100C is provided with one power transmission circuit 120 in common for each segment Seg. Each segment Seg is provided with a switch circuit 128 that opens and closes the connection between the power transmission resonance circuit 110 and the power transmission circuit 120. The opening and closing of each switch circuit 128 is executed according to the control information SD supplied from the control device 140 to each switch circuit 128. As a result, switching of the power transmission state of each segment Seg is controlled. Also in this configuration, the segment switching position can be controlled as in the above embodiment.

(2) In the above embodiment, a configuration in which the current flowing through the transmission coil 112 of the transmission resonance circuit 110 is used as "information on the electric power supplied to the transmission coil" to control the switching of the segment Seg for transmission will be described as an example. However, the input current or output current of the inverter circuit 122 may be used as "information on the electric power supplied to the transmission coil". Further, the voltage applied between the transmission coils 112 may be used as information on electric power to control the switching of the segment Seg for transmitting power.

(3) In the above embodiment, the case where both the power transmission coil 112 on the power transmission side and the power reception coil 212 on the power reception side are single-phase is described as an example. However, it is not limited to this. The power transmission side may be configured as a multi-phase power transmission coil. Further, the power receiving side may be configured as a multi-phase power receiving coil. For example, the power transmitting side may be a single-phase conductive coil, and the power receiving side may be a two-phase or three-phase or more multi-phase power receiving coil. Further, the power transmission side may have a configuration of two-phase or three-phase or more multi-phase power transmission coils, and the power reception side may have a single-phase or multi-phase power reception coil configuration. Even in the case of a configuration of a multi-phase power transmission coil or a power reception coil, as described in the embodiment, it is possible to control switching of the segment Seg for power transmission by using it as information on electric power such as a current flowing through the power transmission coil. .. When the power transmission side has a plurality of phases, it is easier to control the switching position to be determined and corrected by using the input current or the output current of the inverter circuit 122 as information on electric power.

(4) In the above embodiment, the power transmission resonance circuit and the power reception resonance circuit using series resonance have been described as an example, but the present invention is not limited to this, and the power transmission resonance circuit and the power reception resonance circuit using parallel resonance may also be used. Often, one may be a resonant circuit utilizing series resonance and the other using parallel resonance.

The present disclosure is not limited to the above-described embodiment, and can be realized by various configurations within a range not deviating from the gist thereof. For example, the technical features in the embodiments corresponding to the technical features in each form described in the column of the outline of the invention may be used to solve some or all of the above-mentioned problems, or one of the above-mentioned effects. It is possible to replace or combine as appropriate to achieve a part or all. Further, if the technical feature is not described as essential in the present specification, it can be appropriately deleted.

100, 100C ... power supply device, 110 ... power transmission resonance circuit, 112 ... power transmission coil, 140 ... control device, 200 ... vehicle, 205 ... power reception device, 210 ... power reception resonance circuit, 212 ... power reception coil, Seg ... segment

Claims (6)

It has a power feeding device (100) and a power receiving device (205) mounted on a moving body (200) and whose position relative to the power feeding device changes, and the power receiving device does not contact the power receiving device. It is a non-contact power supply system that is powered by
The power receiving device includes a power receiving resonant circuit (210) including at least one power receiving coil (212).
The power supply device
A plurality of segments (Segs) having a power transmission resonant circuit (110) including at least one power transmission coil (112) that transmits power to the power receiving device via the power receiving coil.
By comparing the information about the power supplied to the power transmission coil in the segment that transmits power to the power receiving device, the segment that continues the power transmission to the power receiving device, the segment that stops the power transmission, and the power transmission A control device (140) that controls the operation of the segment that starts
A non-contact power supply system. The non-contact power supply system according to claim 1.
The control device has the power transmission coil of the power transmission continuing segment and the power receiving device according to the result of comparing the information regarding the electric power in the power transmission continuing segment with the power information in the power transmission stopping segment. A non-contact power feeding system that estimates the relative positional relationship with the power receiving coil of the power transmission and determines the timing of switching between the segment that stops the power transmission and the segment that starts the power transmission according to the estimation result. The non-contact power supply system according to claim 2.
The comparison of the information about the electric power is performed by the absolute value or the absolute value of the difference between the value of the information about the electric power in the segment that continues the transmission and the value of the information about the electric power in the segment that stops the transmission. A non-contact power supply system. The non-contact power supply system according to claim 2.
The comparison of the information about the electric power is performed by comparing the value of the information about the electric power in the segment for stopping the power transmission with the other segments other than the segment for stopping the power transmission before the timing of switching the segment for stopping the power transmission. It is performed by the absolute value of the difference or the absolute value of the ratio from the value of the information about the power supplied to the power transmission coil when the power transmission is switched and the segment that stops the power transmission is in the state of continuing the power transmission. , Contactless power transmission system. The non-contact power supply system according to claim 3 or 4.
The timing of switching the segment is determined by comparing the value of the information about the electric power of the segment that stops the power transmission with the value of the information about the electric power supplied to the transmission coil of the segment that starts the power transmission. The relative positional relationship between the power transmission coil of the segment that continues power transmission and the power reception coil of the power receiving device is estimated, and the timing of switching between the segment that stops power transmission and the segment that starts power transmission is determined according to the estimation result. A non-contact power supply system that compensates. A control method for a non-contact power feeding system in which power is supplied from the power feeding device (100) to a power receiving device (205) mounted on a moving body (200) and whose position relative to the power feeding device fluctuates. And
The power receiving device includes a power receiving resonant circuit (210) including at least one power receiving coil (212).
The power feeding device comprises a plurality of segments (Segs) having a power transmission resonant circuit (110) including at least one power transmission coil (112) that transmits power to the power receiving device via the power receiving coil.
By comparing the information about the power supplied to the power transmission coil in the segment that transmits power to the power receiving device, the segment that continues the power transmission to the power receiving device, the segment that stops the power transmission, and the power transmission A method of controlling a contactless power system that controls the operation of the segment that initiates.

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