JP7213930B2 - Transmitting circuit and receiving circuit - Google Patents

Description

The present invention relates to a signal transmission circuit, a battery monitoring device and a battery monitoring method.

2. Description of the Related Art In a battery device such as an electric vehicle, the entire device is controlled while monitoring a large amount of information such as the voltage and temperature of each battery cell that constitutes the battery. For example, such a battery device is provided with a control circuit that controls the entire device, and a measurement circuit that includes operational amplifiers and the like for measuring the voltage and temperature of individual battery cells. The control circuit performs control based on information such as voltage and temperature measured by the measurement circuit.

A battery is composed of a large number of battery cells connected in series, and the potential difference between both ends reaches several hundreds of volts. Furthermore, the potential of the terminal connected to each battery cell fluctuates greatly due to changes in current amount and polarity due to acceleration and deceleration of an electric vehicle or the like. On the other hand, the control circuit that controls the entire device is a digital circuit that operates at 5V or less. Therefore, it is necessary to transmit information such as voltage and temperature between blocks with a potential difference of several hundred volts. It is necessary to perform signal transmission while insulating between blocks having a potential difference.

A device using a photocoupler and an isolation transformer has been proposed as a device that performs signal transmission while insulating blocks having a potential difference (for example, Patent Document 1).

JP 2014-135838 A

Signal transmission between blocks with a potential difference has used transformers, photocouplers, high-voltage semiconductor parts, and the like, as in the above-described prior art, but these parts are large and expensive. In a device that requires high reliability, the transmission path must be duplicated, but in that case, double the number of high-voltage semiconductor parts, transformers, and photocouplers are required, making the device even larger and more expensive.

In addition, a measuring circuit composed of an operational amplifier or the like is provided for measuring the voltage and temperature of individual battery cells, and it is necessary to supply power to this measuring circuit. It is conceivable to power the measurement circuit from individual battery cells, but this would render the circuit inoperable when the battery cell is fully discharged.

In addition, it measures the voltage and current of high-voltage power lines in industrial equipment, office equipment, home appliances, and photovoltaic equipment that operate on commercial AC power supplies of 100 V or higher, and digital circuits that operate at low voltages. It is necessary to process and control with the same problem.

In addition, since these devices are controlled by the on/off timing of transistors and thyristors such as chopper control, the timing of information exchange is important, and there is a problem that long information transmission time and fluctuation of delay time cannot be tolerated. rice field.

In addition, high-voltage semiconductor parts, transformers, and photocouplers are physically fixed, and the positions of the transmitting side and the receiving side cannot be changed or rotated. Connectors with contacts are required for these attachments and detachments, and connection reliability is an issue. Also, it cannot be submerged in water.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides a signal transmission device and a battery monitoring device that are capable of transmitting signals between blocks having a potential difference with high reliability and with a small-scale configuration. for the purpose.

A power transmission circuit according to the present invention includes an operation circuit that operates based on a first voltage from a power supply, a measurement circuit that measures an electrical signal based on the first voltage to obtain measurement data, and the first voltage. a processing control circuit that operates based on a second voltage obtained by converting the voltage to a voltage lower in voltage level than the first voltage, and controls the operation of the operation circuit based on the measurement data. A power transmission circuit that transmits and receives signals to and from a device, and has a power transmission side resonance circuit composed of a power transmission coil and a power transmission side resonance capacitor. While transmitting electric power, the measurement data is received via the power transmission coil and supplied to the processing control circuit of the operating device.

A power receiving circuit according to the present invention includes an operating circuit that operates based on a first voltage from a power supply, a measuring circuit that measures an electrical signal based on the first voltage to obtain measurement data, and a processing control circuit that operates based on a second voltage obtained by converting the voltage to a voltage lower in voltage level than the first voltage, and controls the operation of the operation circuit based on the measurement data. A power-receiving circuit that transmits and receives signals to and from a device, and has a power-receiving-side resonance circuit composed of a power-receiving coil and a power-receiving-side resonance capacitor, and measures the power transmitted to the power-receiving coil by an alternating magnetic field without contact. It is characterized by transmitting the measurement data obtained from the measurement circuit while supplying the measurement data to the circuit.

According to the signal transmission device of the present invention, it is possible to perform signal transmission between blocks having a potential difference with high reliability and with a small-scale configuration.

2 is a block diagram showing the configuration of an operation device including the signal transmission device of Example 1; FIG. 3 is a block diagram showing the configuration of a power receiving side circuit; FIG. It is a block diagram which shows the structure of the power transmission side circuit. It is the top view (a) of the conductor pattern of a power transmission coil and a receiving coil, and the perspective view (b) of a cross section. FIG. 4 is a plan view showing the positional relationship between the conductor patterns of the power transmitting coil and the power receiving coil and the resonance capacitor; FIG. 4 is a plan view showing another example of conductor patterns of the power transmitting coil and the power receiving coil; FIG. 4 is a plan view showing another example of conductor patterns of the power transmitting coil and the power receiving coil; FIG. 11 is a block diagram showing the configuration of a signal transmission device according to a second embodiment; FIG. 4 is a flowchart showing operations of a power transmission circuit and a power reception circuit including timing notification operations; FIG. 11 is a block diagram showing the configuration of a battery monitoring device of Example 3; 3 is a block diagram showing details of a power receiving block including a power receiving side circuit; FIG. FIG. 4 is a block diagram showing another configuration example of the battery monitoring device; 4 is a flow chart showing a battery monitoring operation; FIG. 4 is a diagram showing a circuit example in which a power receiving side circuit has a resonance switching circuit; FIG. 4 is a block diagram showing another configuration example of the battery monitoring device; It is a figure which shows typically the antenna structure of a battery monitoring apparatus. It is a figure which shows typically the antenna structure of a battery monitoring apparatus. It is a figure which shows the structural example of a power transmission coil. 2 is a block diagram showing the configuration of a battery monitoring device in which a capacitor is connected in series with a power transmission coil; FIG. 1 is a block diagram showing the configuration of a battery monitoring device in which a capacitor is connected in series with a power receiving coil; FIG. FIG. 11 is a block diagram showing the configuration of a battery monitoring device of Example 4; It is a figure which shows typically the antenna structure of a battery monitoring apparatus. It is a figure which shows typically the antenna structure of a battery monitoring apparatus.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description of each embodiment and the attached drawings, substantially the same or equivalent parts are denoted by the same reference numerals.

FIG. 1 is a block diagram showing the overall configuration of an apparatus including an operating device 100, a power receiving circuit 200, and a power transmitting circuit 300 according to this embodiment. The power receiving circuit 200 and the power transmitting circuit 300 constitute a signal transmission device 400 .

Operating device 100 includes high voltage circuit 10 , transformer 11 , rectifier circuit 12 , low voltage circuit 13 and measurement circuit 14 .

The high-voltage circuit 10 is a high-voltage operation circuit, such as an electric motor, a heating device, an electric furnace, a chemical reaction layer, or the like, which operates based on a high-voltage AC voltage. The high voltage circuit 10 operates based on the AC voltage supplied from the AC power supply ACS. The AC power supply ACS is a power supply that sends out a commercial power supply AC of 100 V AC, for example.

The transformer 11 is provided in parallel with a voltage supply line connecting the AC power supply ACS and the high voltage circuit 10, and converts the voltage level of the AC voltage sent from the AC power supply ACS from 100V to 5V, for example.

The rectifier circuit 12 includes, for example, a diode bridge to which four rectifying diodes are connected and a smoothing capacitor. The rectifier circuit 12 performs full-wave rectification and smoothing of the AC voltage (eg AC 5V) whose voltage level has been converted by the transformer 11 to generate a DC voltage (eg DC 5V). The rectifier circuit 12 supplies the generated DC voltage to the low voltage circuit 13 .

The low voltage circuit 13 is composed of, for example, a digital circuit and a CPU, and controls the high voltage circuit 10 and the entire device by supplying a control signal CS. Also, the low voltage circuit 13 supplies a predetermined power V1 to the power transmission circuit 300 . The low voltage circuit 13 performs these operations based on the DC voltage supplied from the rectifier circuit 12 .

The measurement circuit 14 measures the voltage of the AC power supply ACS by dividing it with a resistor R1 (for example, 100 kΩ). Also, the measurement circuit 14 measures the alternating current from the voltage across the resistor R2 (for example, 1Ω) connected to the alternating current power supply ACS. The measurement circuit 14 AD-converts the measured voltage value and current value, extracts them as data, and supplies them to the power receiving side circuit 20 as measurement data Md.

The power receiving circuit 200 is composed of a power receiving coil RC and a power receiving side circuit 20 . The power transmission circuit 300 is composed of the power transmission coil TC and the power transmission side circuit 30 .

FIG. 2 is a block diagram showing the configuration of the power receiving circuit 200. As shown in FIG.

The receiving coil RC forms a resonance circuit 21 together with the resonance capacitor C1. The power receiving coil RC and the resonance capacitor C1 are magnetically coupled to a high-frequency (for example, 13.56 MHz) alternating magnetic field generated by the power transmitting coil TC of the power transmitting circuit 300, and generate an alternating voltage (high frequency signal) corresponding to the alternating magnetic field. and apply it to lines L1 and L2. Although the resonance circuit 21 is configured as a parallel resonance circuit in which the receiving coil RC and the resonance capacitor C1 are connected in parallel, it may be a series resonance circuit or a combination of both.

The rectifier circuit 22 includes a diode bridge to which four rectifying diodes D1 to D4 are connected and a smoothing capacitor SC. The rectifier circuit 22 full-wave rectifies and smoothes the AC voltages (high frequency power) on the lines L1 and L2 to convert them into DC voltages, applies them to the lines L5 and L6, and supplies them to the power supply and bias circuit 23 .

The power supply and bias circuit 23 includes a power supply circuit 24 that supplies power supply voltage to the communication circuit 26 and the control circuit 27, and a bias circuit 25 that supplies bias voltage and bias current to the communication circuit 26 and the control circuit 27. there is

The communication circuit 26 operates based on the power supply voltage from the power supply circuit 24 and the bias voltage and bias current from the bias circuit 25, and uses the high-frequency signal from the power receiving coil RC as a clock to perform bidirectional communication by ASK (Amplitude Shift Keying) modulation. communicate. The communication circuit 26 performs two-way communication with the power transmission side circuit 30 via the power receiving coil RC.

The control circuit 27 operates based on the power supply voltage from the power supply circuit 24 and the bias voltage and bias current from the bias circuit 25, and controls the overall operation of the power receiving side circuit 20 by exchanging data and clocks with the communication circuit 26. do.

FIG. 3 is a block diagram showing the configuration of the power transmission circuit 300. As shown in FIG.

The AC signal source 31 is composed of a crystal oscillation circuit or the like, generates an AC signal of 13.56 MHz, and supplies it to the drive circuit 32 .

The drive circuit 32 amplifies the power of the AC signal supplied from the AC signal source 31 to generate a drive current and sends it to lines L3 and L4. As a result, a high-frequency current flows through the power transmitting coil TC.

The control circuit 33 exchanges data and clocks with the communication circuit 34 and controls the operation of the entire power transmission side circuit 31 .

The communication circuit 34 performs two-way communication by ASK modulation via the power transmission coil TC. Note that the communication circuit 34 may perform communication using an NFC (Near Field Communication) communication method or the like.

The power transmission coil TC forms a resonance circuit 35 together with the resonance capacitor C2. The power transmission coil TC and the resonance capacitor C2 generate an alternating magnetic field based on the drive current supplied from the drive circuit 32 . Although the resonance circuit 35 is configured as a parallel resonance circuit in which the power transmission coil TC and the resonance capacitor C2 are connected in parallel, it may be a series resonance circuit or a combination of both.

ASK modulation with a modulation index of about 10%, for example, is used in communication by magnetic field coupling between the power transmitting coil TC and the power receiving coil RC. Thereby, communication can be performed while power is being supplied.

Next, referring to FIG. 1 again, the operation of the signal transmission device 400 of this embodiment will be described.

First, when the operating device 100 is activated, the low-voltage circuit 13 starts operating based on the DC voltage of 5 V obtained by converting the AC voltage of 100 V from the AC power supply ACS with the transformer 11 and the rectifier circuit 12 . . The low voltage circuit 13 supplies a control signal CS to operate the high voltage circuit 10 . Thereby, the operating device 100 starts to operate. Also, the low voltage circuit 13 supplies the power V1 to the power transmission side circuit 30 of the power transmission circuit 300 .

The power transmission side circuit 30 receives power V1 from the low voltage circuit 13, applies high frequency power of 13.56 MHz to the power transmission coil TC, and generates a high frequency AC magnetic field (hereinafter referred to as a high frequency magnetic field). The power transmitting coil TC and the power receiving coil RC are magnetically coupled by the generated high frequency magnetic field, and generate high frequency power by electromagnetic induction. High-frequency power and a clock of 13.56 MHz are supplied to the power receiving side circuit 20 via the power receiving coil RC.

The power receiving side circuit 20 supplies part of the high frequency power obtained via the power receiving coil RC to the measurement circuit 14 as the power V2. The measurement circuit 14 measures the voltage and current of the AC power supply ACS, performs AD conversion, and generates measurement data Md. The measurement circuit 14 supplies the measurement data Md to the power receiving circuit 20 .

The power receiving side circuit 20 transmits the measurement data Md to the power transmission circuit 300 via the power receiving coil RC. The power transmission side circuit 30 of the power transmission circuit 300 receives the measurement data Md via the power transmission coil TC.

The power transmission side circuit 30 supplies the measurement data Md to the low voltage circuit 13 . The low voltage circuit 13 makes various judgments based on the measurement data Md and controls the high voltage circuit 10 .

As described above, in the signal transmission device 400 of the present embodiment, exchange of the measurement data Md and power supply to the measurement circuit 14 are performed using a 13.56 MHz high-frequency magnetic field generated by magnetic field coupling between the power transmission coil TC and the power reception coil RC. conduct.

According to the signal transmission device 400 of the present embodiment, signal transmission can be performed by magnetic field coupling between the power transmitting coil TC and the power receiving coil RC, so electrical isolation can be easily achieved. Therefore, expensive and large parts such as photocouplers and transformers are not required.

In addition, since power can be supplied to the measurement circuit 14 by magnetic field coupling of the power transmission coil TC and the power reception coil RC, a sensor circuit, an operational amplifier circuit for signal processing, an AD converter circuit, and a digital circuit for arithmetic processing can be used. It can be arranged as a measurement circuit 14 . Therefore, it is possible to realize a highly functional and high-performance device capable of advanced measurement and data processing, compression of communication data, and the like.

Further, the power transmitting coil TC and the power receiving coil RC can be shielded from the outside world by a magnetic sheet or the like, so that external interference and information leakage can be easily prevented.

In addition, since the power transmitting coil TC and the power receiving coil RC are detachable and can be operated while rotating or changing their positions, an inexpensive and highly reliable signal connection point can be achieved by eliminating electrical contacts. can be created.

In addition, since the power transmitting coil TC and the power receiving coil RC can operate even when they are immersed in water, they can be used for sending and receiving measurement data in the sea or underwater.

The power supply to the measurement circuit 14 and the like by the magnetic field may be performed in parallel with the communication operation by the magnetic field coupling, or may be performed by an unmodulated high-frequency magnetic field in which no communication is performed.

Next, configurations of the power transmitting coil TC and the power receiving coil RC will be described with reference to FIGS. 4(a) and 4(b).

The power transmitting coil TC and the power receiving coil RC are provided on both sides of a substrate made of an insulating material (for example, substrate material FR-4, thickness 1.6 mm). a conductor pattern of the power transmitting coil is formed in the second wiring layer, a conductor pattern of the power receiving coil is formed in the second wiring layer, and wiring is provided in vias connecting the first wiring layer and the second wiring layer. there is

FIG. 4A is a plan view of the conductor pattern of the power transmitting coil TC viewed from the first wiring layer side of the substrate, and a plan view of the conductor pattern of the power receiving coil RC viewed from the second wiring layer side of the substrate. is a plan view of the. FIG. 4(b) is a cross-sectional perspective view of the power transmitting coil TC and the power receiving coil RC in the broken line portion of FIG. 4(a).

Each of the power transmitting coil TC and the power receiving coil RC has a conductor pattern in which a conductive wire made of copper foil with a thickness of 35 μm, for example, is formed in a spiral shape with two or more turns (the number of turns exceeds one). An end of the conductor pattern of the power transmission coil TC is connected to the power transmission side circuit 30 . An end of the conductor pattern of the power receiving coil RC is connected to the power receiving side circuit 20 .

As shown in FIG. 4(a), the power transmitting coil TC includes a wiring portion WP1 made of a continuous conductive wire, one end of which is connected to a resonance capacitor C2 (not shown) that forms a resonance circuit, and a first wiring portion WP1 connected to the resonance capacitor C2. and a spiral portion SP1 consisting of a spiral-shaped continuous conductor connected to the end of the spiral portion SP1. The spiral portion SP1 has a conductor portion that crosses between the second end of the spiral portion SP1 and the other end of the wiring portion WP1 (indicated by a cross in the figure).

Further, the power transmitting coil TC has a connecting portion that connects the second end of the spiral portion SP1 and the other end of the wiring portion WP1. The connection portion includes a continuous conductor portion CP1 provided in the second wiring layer and a via wiring portion VP passing through a pair of vias provided between the first wiring layer and the second wiring layer. ing. That is, the conductor portion CP1 and the via wiring portion VP realize the crossing of the wires of the power transmitting coil TC.

The power receiving coil RC includes a wiring portion WP2 formed of a continuous conductor wire having one end connected to a resonance capacitor C1 (not shown) forming a resonance circuit, and a spiral-shaped wiring portion WP2 having a first end connected to the resonance capacitor C1. and a spiral portion SP2 consisting of a continuous wire. The spiral portion SP2 has a conductor portion that crosses between the second end of the spiral portion SP2 and the other end of the wiring portion WP2 (indicated by a cross in the drawing).

In addition, the power receiving coil RC has a connecting portion that connects the second end of the spiral portion SP2 and the other end of the wiring portion WP2. The connecting portion is a continuous conductor portion CP2 provided in the first wiring layer as shown in FIG. 4(a) and between the first wiring layer and the second wiring layer as shown in FIG. 4(b). and a via wiring portion VP passing through a pair of vias provided in the . That is, the conductor portion CP2 and the via wiring portion VP realize the crossing of the wires of the receiving coil RC.

The conductor portion CP1 of the connecting portion of the power transmitting coil TC is provided at a position separated (that is, insulated position) from the spiral portion SP2 of the power receiving coil RC in the second wiring layer. Similarly, the conductor portion CP2 of the connection portion of the power receiving coil RC is provided at a position separated (that is, at an insulated position) from the spiral portion SP1 of the power transmitting coil TC in the first wiring layer.

Also, the conductor portion CP1 of the connecting portion of the power transmitting coil TC is arranged inside the inner diameter of the spiral portion SP2 of the power receiving coil RC in the second wiring layer. The conductor portion CP2 of the connection portion of the power receiving coil RC is arranged inside the inner diameter of the spiral portion SP1 of the power transmitting coil TC in the first wiring layer.

The spiral portion SP1 of the power transmitting coil TC and the spiral portion SP2 of the power receiving coil RC are arranged to overlap each other via the first wiring layer, the substrate and the second wiring layer, except for the portions where the conductor portions CP1 and CP2 are located. It is

The power transmitting coil TC and the power receiving coil RC are coils that handle a high frequency magnetic field of 13.56 MHz, and preferably have an inductance of about 0.5 to 1 microhenry. The reason for this is that the reactance of the coil is about 42.6 to 85.2 Ω, which is suitable for use with a power supply voltage of about 5 V, which is often used in electronic equipment. On the other hand, the outer diameter size of the coil is preferably about 20 mm from the convenience of the device size. In order to satisfy these conditions, the coil is preferably formed in a spiral shape with two or more turns (the number of turns exceeds one), and it is necessary to intersect while insulating.

In the power transmitting coil TC and the power receiving coil RC of the present embodiment, the conductive wire portions (CP1, CP2) provided in the wiring layer on the side opposite to the spiral portions (SP1, SP2) and the via wiring portions (CP1, CP2) provided in the pair of vias ( VP) realizes crossing while insulating. According to this configuration, it is possible to achieve crossovers while insulating with an inexpensive two-layer printed circuit board without using a multi-layer substrate such as four layers.

In addition, a slight disturbance occurs in the area where each coil intersects (hereinafter referred to as the intersection area), but only a slight variation in the self-inductance of each coil and the coupling coefficient of the two coils affects the operation and characteristics. is small enough.

In addition, the dielectric strength between the power transmitting coil TC and the power receiving coil RC depends on the thickness of the insulating substrate sandwiched between the front and back conductors, the conductor pattern (the spiral portion SP1, the wiring portion WP1) of the power transmitting coil TC in the first wiring layer, and the power receiving coil. The distance in the plane direction from the conductor pattern (conductor portion CP2) of RC, the conductor pattern (spiral portion SP2, wiring portion WP2) of the power receiving coil RC and the conductor pattern (conductor portion CP1) of the power transmission coil TC in the second wiring layer. can be ensured by setting the distance in the plane direction of and to safe sizes, respectively. At this time, it is possible to widen the distance between the conductor pattern of the power transmitting coil TC and the conductor pattern of the power receiving coil RC in each layer according to the desired insulation distance.

In addition, since the intersecting regions (conductor portions CP2, CP1) are provided inside the inner diameters of the spiral portions (SP1, SP2), a compact device can be realized without increasing the occupied area.

FIG. 5 is a plan view showing the positional relationship between the conductor patterns of the power transmitting coil TC and the power receiving coil RC and the resonance capacitors C1 and C2.

A connection line between the wiring portion WP1 and the spiral portion SP1 and the resonance capacitor C2 (in the figure, a straight line portion where the wiring portion WP1 and the spiral portion SP1 run in parallel) is provided with a land pattern C2a for soldering connection of the resonance capacitor C2. and C2b are provided. The land patterns C2a and C2b are provided at intervals within three times the wiring interval of the coil portion of the power transmission coil TC.

Similarly, a connection line between the wiring portion WP2 and the spiral portion SP2 and the resonance capacitor C1 (in the drawing, a straight portion where the wiring portion WP2 and the spiral portion SP2 run in parallel) is provided with a soldering wire for connecting the resonance capacitor C1. Land patterns C1a and C1b are provided. The land patterns C1a and C1b are provided at intervals within three times the wiring interval of the coil portion of the receiving coil RC.

The longer the conductor patterns of the power transmitting coil TC and the power receiving coil RC follow each other between the layers, the more magnetic lines of force interlink each other, and the coupling coefficient can be increased. Also, a large current flows through the path between each coil and each resonance capacitor at the time of resonance. By arranging the capacitors close to each other, it is possible to reduce the self-interlinking magnetic lines of force and prevent a decrease in the coupling coefficient.

Note that, unlike the above, as shown in FIG. 6, one of the intersection regions is arranged inside the inner diameter of the coil (that is, inside the spiral portion), and the other is arranged outside the outer diameter of the coil (that is, inside the spiral portion). outside). For example, if it is necessary to take a large distance in the plane direction to ensure insulation on either side of the printed circuit board, placing the intersection area outside the outer diameter of the coil makes The increase in occupied area can be kept to a minimum while securing a large insulation distance.

Also, as shown in FIGS. 7(a) and 7(b), both intersection regions may be arranged outside the outer path of the coil. If it is necessary to keep a large distance in the plane direction to ensure insulation on both sides of the printed circuit board, arranging the intersection area outside the outer diameter of the coil will result in a longer insulation distance than when arranging it inside. It is possible to keep the increase in the exclusive area to a minimum while keeping the

Note that the power receiving coil RC may be formed on the first wiring layer, and the power transmitting coil TC may be formed on the second wiring layer.

4(a) and (b), FIG. 5, FIG. 6, FIG. 7(a) and (b) show examples in which the power transmission coil TC and the power reception coil RC have a rectangular shape. may be curved, square, circular, elliptical, polygonal, or the like.

Also, although the conductor layer is composed of two layers, the first wiring layer and the second wiring layer, a plurality of conductor layers of a multi-layer substrate having two or more layers may be used. For example, the surface of each coil can be insulated by using the middle two of the four conductor layers as wiring layers.

FIG. 8 is a block diagram showing the configuration of the signal transmission device 410 of this embodiment. The signal transmission device 410 differs from the signal transmission device 400 of the first embodiment in that the power reception circuit 210 has the clamp circuit 28 and the power transmission circuit 310 has the current measurement circuit 36 .

A clamp circuit 28 is provided at the output side of the rectifier circuit 22 between lines L5 and L6. Clamp circuit 28 includes a Zener diode and a connecting switch. The clamp circuit 28 switches the state of the connection switch between on and off in accordance with the supply of the load switching signal from the control circuit 27 . As a result, the load state of the rectifier circuit 22 changes, and the state of the high-frequency magnetic field changes. That is, the clamp circuit 28 is a load switching circuit that switches the load state according to the load switching signal.

A current measurement circuit 36 is provided in the drive circuit 32 . The current measurement circuit 36 detects changes in the high-frequency magnetic field based on the currents flowing through the lines L3 and L4, and notifies the control circuit 33 of the detection results.

The operations of the clamp circuit 28 and the current measurement circuit 36 allow the power receiving circuit 210 to notify the power transmitting circuit 310 . The operation of the power transmission circuit and the power reception circuit including the timing notification operation will be described with reference to the flowchart of FIG.

First, the power transmission circuit 310 is activated to generate a high frequency magnetic field from the power transmission coil TC (step S101). The power transmission circuit 310 supplies power and a clock to the power reception circuit 210 . The power receiving circuit 210 is activated in response to power supply and clock supply (step S201).

The power transmission circuit 310 and the power reception circuit 210 transmit and receive communication messages by two-way communication via magnetic field coupling between the power transmission coil TC and the power reception coil RC. Power transmission circuit 310 continues to supply power and clocks in parallel with transmission and reception of communication messages. Then, each of the power transmission circuit 310 and the power reception circuit 210 performs initial setting based on the setting information obtained by transmission/reception of the communication message, and performs normality diagnosis to diagnose whether or not it is in a state in which it can operate normally. (Steps S102, S202).

The control circuit 27 of the power receiving circuit 210 determines whether the high frequency magnetic field is in a steady state (step S203). If it is determined that it is not in a steady state (step S203: No), the process proceeds to step S210 and stops the operation.

On the other hand, if it determines that it is a steady state (step S203: Yes), the control circuit 27 will determine whether the timing notification is required (step S204).

If it is determined that timing notification is necessary (step S204: Yes), the control circuit 27 controls the clamp circuit 28 to switch between ON and OFF states (step S205). This causes the high-frequency magnetic field to fluctuate.

The control circuit 33 of the power transmission circuit 310 determines whether the high-frequency magnetic field is in a steady state (step S103). If it is determined that it is not in a steady state (step S103: No), the process proceeds to step S109, and the high-frequency magnetic field and the operation of the device are stopped.

On the other hand, if it is determined to be in a steady state (step S103: Yes), the current measurement circuit 36 detects current fluctuations due to fluctuations in the high-frequency magnetic field, and notifies the control circuit 33 of the detection results (step S104).

The control circuit 33 of the power transmission circuit 310 determines whether information exchange (communication) with the power reception circuit 210 is necessary (step S105). Similarly, the control circuit 27 of the power receiving circuit 210 determines whether information transfer (communication) with the power transmitting circuit 310 is necessary (step S206).

When it is determined that information exchange with the power receiving circuit 210 is necessary (steps S105 and S206: Yes), the power transmitting circuit 310 and the power receiving circuit 210 perform communication operations by magnetic field coupling of the power transmitting coil TC and the power receiving coil RC. , exchanges information including communication messages with the power receiving circuit 210 (steps S106 and S207). The power transmission circuit 310 supplies power and a clock to the power reception circuit 210 in parallel with the communication operation.

When the power receiving circuit 210 determines that it is not necessary to exchange information with the power transmitting circuit 310 (step S206: No), the power receiving circuit 210 performs a standby operation (step S208). When the power transmission circuit 310 determines that it is not necessary to exchange information with the power reception circuit 210 (step S105: No), the power transmission coil TC continues to generate a high-frequency magnetic field (step S107).

The control circuit 33 of the power transmission circuit 310 determines whether or not to continue the operation of power supply and clock supply using the high-frequency magnetic field (step S108). Similarly, the control circuit 27 of the power receiving circuit 210 determines whether or not to continue the standby operation for receiving power supply and clock supply (step S209).

When the control circuit 33 of the power transmission circuit 310 determines to continue power supply and clock supply by the high-frequency magnetic field (step S108: Yes), the process returns to step S103 to determine again whether the high-frequency magnetic field is in a steady state. Similarly, when the control circuit 27 of the power receiving circuit 210 determines to continue the standby operation for receiving the power supply and the clock supply (step S209: Yes), the process returns to step S203 to check again whether the high-frequency magnetic field is in a steady state. make a judgment.

When the power transmission circuit 310 determines not to continue the operation of power supply and clock supply using the high-frequency magnetic field (step S108: No), it stops the high-frequency magnetic field and stops the operation (step S109). When the power receiving circuit 210 determines not to continue the standby operation for receiving power supply and clock supply (step S209: No), it stops the operation (step S210).

By the operation described above, the power receiving circuit 210 notifies the power transmitting circuit 310 at an arbitrary timing.

According to the signal transmission device 410 of the present embodiment, by the operation of the clamp circuit 28 and the current measurement circuit 36, the signal from the power receiving circuit 210 to the power transmitting circuit is generated at an arbitrary timing in addition to the communication based on the magnetic field coupling of the power transmitting coil TC and the power receiving coil RC. 310 can be notified. At this time, by securing the voltage of the clamp circuit 28 to a voltage (for example, 3 V) at which the power supply and the bias circuit 23 can operate, while the power receiving circuit 210 notifying the power transmitting circuit 310, the power transmitting coil TC and the power receiving coil Communication operations using RC can be performed in parallel.

The signal transmission device of this embodiment is particularly effective, for example, when the timing of gate control of the transistors and thyristors of the high-voltage circuit 10 requires time accuracy.

FIG. 10 is a block diagram showing the configuration of the battery monitoring device 500 of this embodiment. The battery monitoring device 500 is provided in a battery-powered device such as an electric vehicle, and monitors the charging state of four battery cells 72a to 72d (hereinafter collectively referred to as a battery cell group) connected in series. It is a monitoring device.

A power receiving circuit 71a is connected to the battery cell 72a. A power receiving coil RC1 is connected to the power receiving side circuit 71a. The power receiving coil RC1, the power receiving side circuit 71a, and the battery cell 72a constitute a power receiving circuit 700a. Similarly, each of the battery cells 72b to 72d is provided with a corresponding power receiving side circuit (71b to 71d) and a corresponding power receiving coil (RC2 to RC4) to configure power receiving circuits 700b to 700d. In the following description, when describing a configuration common to the power receiving circuits 700a to 700d, these are also referred to as power receiving circuits 700. FIG.

FIG. 11 is a block diagram showing details of a power receiving circuit 700a including a power receiving circuit 71a. A measurement circuit 73 for measuring the voltage value and temperature of the battery cell 72a is provided between the power receiving side circuit 71a and the battery cell 72a. Power receiving circuits 700b to 700d also have the same configuration.

The measurement circuit 73 divides the voltage of the battery cell 72a by the resistor R3 and measures it. The measurement circuit 73 also measures the temperature of the battery cell 72a with the thermistor T1. The measurement circuit 73 also has a switch SW0 and a resistor R4 for forcibly discharging the battery cell 72a, and discharges the battery cell 72a by turning on the switch SW0 according to the control of the power receiving side circuit 71a.

The power receiving side circuit 71 a includes a power supply circuit 74 , a communication circuit 75 , a memory 76 , an ADC (Analog Digital Converter) 77 and a control circuit 78 .

The power supply circuit 74 supplies power supply voltage to each part of the power receiving side circuit 71a based on the power supplied by the magnetic field coupling of the power transmitting coil TC1 and the power receiving coil RC1.

The communication circuit 75 transmits and receives information by ASK modulation via the power receiving coil RC1. The communication circuit 75 transmits, for example, monitoring data obtained by the measurement circuit 73 to the power transmission side circuit 61 via the power receiving coil RC1.

The memory 76 is a non-volatile memory, and holds control information for communication (for example, NFC communication ID) and address information, as well as the serial number and history information of the battery cell 72a.

The ADC 77 AD-converts the voltage value and temperature measured by the measurement circuit 73 to generate monitoring data.

The control circuit 78 controls each part of the power receiving side circuit 71a. The control circuit 78 also controls forced discharge of the battery cells via the resistor R4 and the switch SW0.

Referring to FIG. 10 again, the battery monitoring device 500 has a power transmission circuit 600 and power transmission coils TC1 to TC4 connected thereto. The power transmitting coils TC1 to TC4 are provided at positions corresponding to the power receiving coils RC1 to RC4, respectively (that is, magnetically coupled positions).

The power transmission circuit 600 has a power transmission side circuit 61 and switches SW1 to SW8.

The power transmission side circuit 61 controls on/off of the switches SW1 to SW8 to select any one of the four power transmission coils TC1 to TC4, transmits a high frequency signal of 13.56 MHz, and generates a high frequency magnetic field from the selected power transmission coil. generate A high-frequency electromotive force is generated by electromagnetic induction in the power receiving coil (one of RC1 to RC4) coupled to the selected power transmitting coil.

The power transmission side circuit 61 supplies power and a clock to the power reception side circuit (one of 71a to 71d) connected to the power reception coil in which the high frequency electromotive force is generated to operate, and transmits control information by a two-way communication function. and send and receive monitoring data. The power transmission side circuit 61 receives input/output of digital signals (indicated as digital I/O in the figure) from a host controller (not shown) and performs these operations.

FIG. 12 is a block diagram showing another configuration example of the battery monitoring device of this embodiment. A power supply line from the power supply circuit 74 of the power receiving side circuit 71a is connected to the battery cell 72a via the switch SW9. The switch SW9 is switched on or off by the control circuit 78 .

The control circuit 78 turns on the switch SW9 and sets the voltage and current of the power supply circuit 74 . As a result, the power receiving side circuit 71a can charge the battery cell with the power obtained from the high frequency magnetic field.

When a plurality of battery cells are connected in series as shown in FIG. 10, it is necessary to match the state of charge of each battery cell. Conventionally, when it is determined that there is variation in the state of charge by voltage measurement, the cells with the higher voltage are forcibly discharged to equalize the state of charge. For this reason, for example, if only one battery cell has a low voltage, all other battery cells must be discharged, resulting in waste of energy and extra time required for such measures. .

However, according to this configuration, it is possible to additionally charge a cell with a low voltage. Therefore, energy and time are wasted by discharging a small number of cells with high voltage and charging them with a small number of cells with low voltage, depending on the state of voltage variation. Therefore, the state of charge of each battery cell can be uniformed.

In the battery monitoring device having such a configuration, the power transmitting side circuit 61 sequentially selects the four power transmitting coils TC1 to TC4 by switching the switches SW1 to SW8 on and off, and sequentially activates and activates the corresponding power receiving side circuits 71a to 71d. The battery monitoring operation is performed by operating and exchanging information. Such battery monitoring operation will be described with reference to the flowchart of FIG.

First, the battery monitoring device 500 is activated, and the device is initialized (step S301).

Next, the power transmission side circuit 61 selects and connects the power transmission coil TC1 by turning on the switches SW1 and SW2 and turning off the other switches SW3 to SW8 to generate a high frequency magnetic field from the power transmission coil TC1.

The power transmission side circuit 61 supplies power and a clock to the power reception circuit 700a via the power transmission coil TC1 and the power reception coil RC1 magnetically coupled thereto. The power receiving circuit 700a measures the voltage and temperature of the battery cell 72a to obtain monitoring data. The power receiving side circuit 71a transmits the monitoring data to the power transmitting side circuit 61 together with the NFC communication ID and other information. The power transmission side circuit 61 receives and takes in the information including the monitoring data, and stores it in a memory (not shown) or the like (step S302).

The power transmission side circuit 61 selects and connects the power transmission coil TC2 by turning on the switches SW3 and SW4 and turning off the other switches SW1, SW2, and SW5 to SW8 to generate a high-frequency magnetic field from the power transmission coil TC2. . As in step S302, the power transmission side circuit 61 supplies power and a clock to operate the power reception circuit 700b, receives monitoring data including voltage and temperature information and other information related to the battery cell 72b, and stores the data in a memory or the like. It is stored (step S303).

The power transmission side circuit 61 selects and connects the power transmission coil TC3 by turning on the switches SW5 and SW6 and turning off the other switches SW1 to SW4, SW7 and SW8 to generate a high frequency magnetic field from the power transmission coil TC3. . As in steps S301 and S302, the power transmission side circuit 61 supplies power and clocks to operate the power reception circuit 700c, receives monitoring data including voltage and temperature information and other information about the battery cell 72c, and stores the information in the memory. etc. (step S304).

The power transmission side circuit 61 selects and connects the power transmission coil TC4 by turning on the switches SW7 and SW8 and turning off the other switches SW1 to SW6 to generate a high frequency magnetic field from the power transmission coil TC4. As in steps S301, S302, and S303, the power transmission side circuit 61 supplies power and clocks to operate the power reception circuit 700d, and receives monitoring data including voltage and temperature information and other information regarding the battery cell 72d. , and stored in a memory or the like (step S305).

The power transmission side circuit 61 determines whether the battery cells 72a to 72d are normal (that is, whether there is an abnormality) based on the obtained monitoring data (step S306). If it is determined that it is not normal (that is, there is an abnormality) (step S306: No), the power transmission side circuit 61 reports information on the abnormal battery cell to the host controller (not shown) (step S307). The process proceeds to S314.

On the other hand, if it is determined to be normal (that is, there is no abnormality) (step S306: Yes), the power transmission side circuit 61 calculates the average value of the voltages of the battery cells 72a to 72d based on the monitoring data. The power transmission side circuit 61 compares the voltage of each of the battery cells 72a to 72d with the average value, and sets the number of cells (the number of high voltage cells) whose voltage is higher than the average value by more than a predetermined allowable width as M, and the average value. The number of cells (the number of low-voltage cells) whose voltage is lower than the predetermined allowable range is set to N (step S308).

The power transmission side circuit 61 determines whether both M and N are zero (that is, whether the difference between the voltage values of all battery cells and the average value is within the allowable range) (S309). ). If it is determined that both M and N are zero (step S309: Yes), the process proceeds to step S314.

On the other hand, when it is determined that either M or N is not zero (step S309: No), the power transmission side circuit 61 determines whether N is less than M, i. It is determined whether or not the number of low voltage devices is smaller than the number of high voltage devices (step S310).

When it is determined that N is equal to or greater than M (N is not less than M) (step S310: No), the power transmission side circuit 61 selects M batteries whose voltage is higher than the average value by a predetermined allowable range. A discharge instruction instructing forced discharge of the cell is transmitted via the power transmission coil corresponding to the battery cell. The power receiving circuit connected to the battery cell to be forcibly discharged turns on the switch SW0 to connect the resistor R4 to the battery cell and forcibly discharge the battery cell (step S311).

On the other hand, when it is determined that N is less than M (step S310: Yes), the power transmission side circuit 61 transmits a high frequency signal from the power transmission coil corresponding to the N battery cells whose voltage is lower than the average value by more than a predetermined allowable range. A magnetic field is generated and power is supplied to the receiving coil corresponding to the transmitting coil. The power receiving side circuit charges the battery cell based on the supplied power (step S312).

The power transmission side circuit 61 determines whether or not to continue the battery monitoring operation (step S313). If it is determined to continue (step S313: Yes), the process returns to step S302, and the monitoring operations of steps S302 to S305 are executed again.

If it is determined not to continue the battery monitoring operation (step S313: No), the power transmission side circuit 61 stops generating the high frequency magnetic field and stops the operation of the battery monitoring device 500. FIG.

By the above operation, battery monitoring and forced discharge of the battery cell group are performed while switching target battery cells by switching the switches.

According to the battery monitoring device 500 of the present embodiment, the information of a plurality of battery cells having a potential difference with each other is transferred to the power receiving side circuit connected to the plurality of battery cells and to a potential different from these (for example, in the case of an electric vehicle). , vehicle body potential) can be exchanged with the power transmission side circuit. Although the potential of the battery cell fluctuates greatly due to charging and discharging, information can be exchanged stably.

Moreover, since the power transmission circuit 600 and the power reception circuit 700 are electrically insulated, there is no leakage current from each battery cell, and energy is not wasted.

In addition, the power transmitting coil and the power receiving coil need only be placed close to each other, and some misalignment and contamination are acceptable.

Moreover, the disconnection between the power transmitting coil and the power receiving coil can be detected by measuring the high-frequency current of the power transmitting coil, so the connection reliability is high. In addition, since a high-frequency magnetic field is used, there are no restrictions on polarity or orientation.

In addition, the range of the high-frequency magnetic field is limited to the vicinity, and malicious access and information leakage from the outside can be prevented. Moreover, by shielding with a magnetic sheet, the prevention of information leakage can be further strengthened.

In addition, since power is supplied to the receiving side circuit by a high-frequency magnetic field, operation is possible even if the battery cell is completely discharged.

With the power receiving circuit 700 separated from the power transmitting circuit 600, by connecting the antenna coil of the NFC reader/writer to the power receiving coil, the power receiving side circuit is activated and operated to read/write information in the non-volatile memory, observe battery cells, can be controlled. As a result, the battery pack including the power receiving circuit 700 can be used alone as an NFC tag.

Further, by turning off all the switches SW1 to SW8 in the power transmission side circuit 61, it is possible to disconnect all the power transmission coils (TC1 to TC4). Therefore, even when the power transmitting coil and the power receiving coil are arranged at positions where they can be coupled to each other, it is possible to access the battery cell from the power transmitting coil of another reader/writer.

In addition, since power on the order of several tens of milliwatts can be supplied to the power receiving side circuit, it is possible to arrange OPAMP circuits and AD converters that measure voltage and current, and perform advanced digital processing and processor processing. It is also possible to encrypt exchanged information and recorded data. In addition, it is possible to control the forced discharge of the battery cell and PWM operation, and display by LED or liquid crystal is also possible.

By providing the power receiving side circuit with a circuit that cuts off the connection on the battery cell side when the magnetic field is weak, it is possible to prevent malfunction even in the event of unexpected magnetic field coupling.

Since the load resistance connected to the resonance circuit including the receiving coil fluctuates significantly between the communication operation and the power supply operation, it is necessary to switch the resonance capacitor. In addition, since the load resistance is large at startup, it is necessary to increase the parallel capacitor in order to operate the resonance circuit as a parallel resonance circuit.

FIG. 14 is a diagram showing a circuit example in which the power receiving side circuit has a resonance switching circuit for switching between communication operation and power supply operation.

A resonance switching circuit 83 is connected between a resonance circuit 81 including a receiving coil RC and a resonance capacitor Ca and a rectifying circuit 82 . The resonance switching circuit 83 has a capacitor Cb, a transistor Q1, a transistor Q2, and a resistor Ra.

One end of the capacitor Cb is connected to a line L11 that is one of connection lines connecting the resonance circuit 81 and the rectifier circuit 82 . The transistor Q1 is an N-channel MOS transistor, for example, and has a base grounded and a drain connected to the other end of the capacitor Cb. The transistor Q2 is an N-channel MOS transistor, for example, and has its base grounded and its drain connected to the gate of the transistor Q1. The resistor Ra has one end connected to one end of the capacitor Cb and the other end connected to a connection end of the gate of the transistor Q1 and the drain of the transistor Q2. Both or one of the transistors Q1 and Q2 may be an NPN bipolar transistor.

The resonance switching circuit 83 switches the resonance capacitor by supplying a resonance switching signal RS from the control circuit 78 to the gate of the transistor Q2.

At startup, the resonance switching signal RS is at L level (ground level) and the transistor Q2 is off. When a magnetic field is applied, charges are supplied through the resistor Ra, the gate potential of the transistor Q1 rises, and the transistor Q1 is turned on. This connects the capacitor Cb to the resonance circuit 81 and increases the parallel capacitance.

By setting the resonance switching signal RS to H level, the transistor Q2 is turned on, and the gate potential of the transistor Q1 is pulled down to the ground potential, so that the transistor Q1 is turned off. As a result, the capacitor Cb is disconnected from the resonance circuit 81, the resonance capacitance is reduced, and a state suitable for power transmission is achieved. Incidentally, the resistor Ra may be connected between the output of the rectifier circuit 82 and the gate of the transistor Q1, and each transistor can be turned on by similarly supplying charges by applying a magnetic field.

FIG. 15 is a block diagram showing the configuration of a battery monitoring device 510, which is another configuration example of the battery monitoring device of this embodiment. The power transmission side circuit 61 is connected to power transmission coils TC11 and TC12 via switches SW11 to SW14. The power transmitting coil TC11 is arranged at a position where it can be magnetically coupled with the power receiving coils RC1 and RC2. The power transmitting coil TC12 is arranged at a position where it can be magnetically coupled with the power receiving coils RC3 and RC4.

The power transmission side circuit 61 controls on/off of the switches SW11 to SW14 to select either of the two power transmission coils TC11 or TC12, transmits a high frequency signal of 13.56 MHz, and generates a high frequency magnetic field from the selected power transmission coil. Let

When the power transmitting coil TC11 is selected, magnetic coupling is performed with either one of the power receiving coils RC1 or RC2. When the transmitter coil TC12 is selected, it magnetically couples with either one of the receiver coils RC3 or RC4. As a result, a high-frequency electromotive force is generated in any one of the receiving coils RC1 to RC4 by electromagnetic induction.

According to this configuration, the number of power transmission coils and the number of wires can be reduced compared to the battery monitoring device shown in FIG.

Next, the antenna structure (coil structure) in the battery monitoring device 500 shown in FIG. 10 will be described with reference to FIGS. 16(a) and 16(b). In the following description, the power transmitting coil is also referred to as a power transmitting antenna, and the power receiving coil is also referred to as a power receiving antenna.

As shown in FIG. 16(a), the power receiving antenna is arranged on the side surface of the battery pack BP. The battery pack BP stores battery cells 72a to 72d and has, for example, a rectangular parallelepiped shape. A power receiving side circuit configured as an integrated circuit is connected to each power receiving antenna.

The power transmission antenna is composed of a spiral conductor pattern inside or on the surface of a flat insulator medium IM such as a strip, tape, string, or plate, and is connected to the selection switch of the power transmission side circuit by the linear conductor pattern. It is Each power transmission antenna may be independently connected to the power transmission side circuit, or may be connected to the power transmission side circuit in a form of branching from the middle.

As shown in FIG. 16(b), each power transmitting antenna is arranged so as to overlap the corresponding power receiving antenna. The power transmitting antenna and the power receiving antenna are fixed by various means such as screwing, incorporation into a frame structure, adhesive tape, or adsorption by a permanent magnet.

According to this configuration, the receiving coil arranged in the battery pack does not become a projection. It is desirable that the surroundings of the power receiving coil are non-magnetic and insulating, but operation is possible even if there is some magnetism or conductivity.

In addition, it is easy to attach and detach, and has excellent connection reliability compared to the case of providing an electrical contact. In addition, even if there is some air gap, dirt, or wetness between the power transmitting coil and the power receiving coil, it can operate.

Also, even if there is a disconnection or an error in connection combination, an abnormality can be detected by confirming the ID of the NFC communication.

In addition, it is suitable for automatic production lines, and since it is a high-frequency signal, it can operate regardless of the winding direction of the coil.

Next, the antenna structure (coil structure) in the battery monitoring device shown in FIG. 15 will be described with reference to FIG.

Two receiving coils are provided on adjacent surfaces (for example, the bottom surface and the top surface) of two adjacent battery packs (BP1 and BP2, BP3 and BP4) and are arranged to face each other. One power transmission coil is sandwiched between two power reception coils (that is, between adjacent surfaces of two battery packs).

According to this configuration, it is possible to reduce the number of power transmission coils and wires without increasing the area and volume, and realize an inexpensive, small, and lightweight device.

The configuration of the power transmission coil may be a configuration in which two power transmission coils TC1 and TC2 are connected in series as shown in FIG. 18(a). A configuration in which two power transmission coils TC1 and TC2 are connected in parallel may be used.

A capacitor may be connected in series with the power transmission coil to the connection line (signal path) between the power transmission side circuit 61 and each power transmission coil. FIG. 19 is a block diagram showing the configuration of a battery monitoring device 520 having such a configuration.

A capacitor C11a is connected between one end of the power transmission coil TC1 and the switch SW1, and a capacitor C11b is connected between the other end of the power transmission coil TC1 and the switch SW2. A capacitor C12a is connected between one end of the power transmission coil TC2 and the switch SW3, and a capacitor C12b is connected between the other end of the power transmission coil TC2 and the switch SW4. A capacitor C13a is connected between one end of the power transmission coil TC3 and the switch SW5, and a capacitor C13b is connected between the other end of the power transmission coil TC3 and the switch SW6. A capacitor C14a is connected between one end of the power transmission coil TC4 and the switch SW7, and a capacitor C14b is connected between the other end of the power transmission coil TC4 and the switch SW8.

Also, a capacitor may be connected in series with the power receiving coil to the connection line (signal path) between each power receiving coil and the power receiving side circuit. FIG. 20 is a block diagram showing the configuration of a battery monitoring device 530 having such configuration.

Capacitors C21a and C21b are connected between the power receiving coil RC1 and the power receiving side circuit 71a. Capacitors C22a and C22b are connected between the power receiving coil RC2 and the power receiving side circuit 71b. Capacitors C23a and C23b are connected between the power receiving coil RC3 and the power receiving side circuit 71c. Capacitors C24a and C24b are connected between the power receiving coil RC4 and the power receiving side circuit 71d.

A high-frequency current of 13.56 MHz is flowing through the power transmitting coil and the power receiving coil, but even if the capacitors are connected in series, the high-frequency current is conducted. be.

Thus, direct current can be blocked by connecting a capacitor in series with the signal path of the power transmitting coil or the power receiving coil. Although the power transmission coil and the power reception coil are originally insulated, even if insulation breakdown occurs due to media breakdown or moisture intrusion into cracks, the direct current element by the capacitor prevents fires and electric shock accidents due to leakage or short circuit. can be done.

The battery monitoring device of this embodiment differs from the battery monitoring device of the third embodiment in that the power transmission circuit is duplicated.

FIG. 21 is a block diagram showing the configuration of the battery monitoring device 800 of this embodiment. The battery monitoring device 800 has a first power transmission circuit 600a and a second power transmission circuit 600b.

The first power transmission circuit 600a has a power transmission side circuit 61a and switches SW1a to SW8a. The power transmission side circuit 61a is connected to one of the power transmission coils TC1a, TC2a, TC3a, and TC4a depending on whether the switches SW1a to SW8a are turned on or off.

The second power transmission circuit 600b has a power transmission side circuit 61b and switches SW1b to SW8b. The power transmission side circuit 61b is connected to one of the power transmission coils TC1b, TC2b, TC3b, and TC4b depending on whether the switches SW1b to SW8b are turned on or off.

FIG. 22 is a diagram showing the antenna structure (coil structure) of the battery monitoring device 800. As shown in FIG. The power receiving antenna is arranged on a side surface of a battery pack BP having, for example, a rectangular parallelepiped shape that stores battery cells, and is connected to a power receiving side circuit configured as an integrated circuit. In both the first power transmission circuit 600a and the second power transmission circuit 600b, the power transmission antenna is configured by a spiral conductor pattern inside or on the surface of the insulating media IM1 and IM2, and the power transmission side circuit is controlled by the linear conductor pattern. is connected to the selection switch.

As shown in FIG. 23, the power transmission antennas of the first power transmission circuit 600a and the second power transmission circuit 600b are arranged so that the central axes of the coils are aligned with the central axes of the corresponding power receiving coils.

Referring to FIG. 21 again, in the operation of the battery monitoring device 800, one of the power transmission side circuit 61a of the first power transmission circuit 600a and the power transmission side circuit 61b of the second power transmission circuit 600b is in an operating state (operation system), and the other is in an operating state (operating system). is controlled to be in a standby state (standby system).

For example, when the power transmission side circuit 61a is an operating system and the power transmission side circuit 61b is a standby system, the switches SW1a to SW8a are controlled to be on or off by a host control circuit (not shown), and the power transmission side circuit 61a is turned on or off by the power transmission coil TC1a. , TC2a, TC3a, and TC4a. The power transmission side circuit 61a exchanges information with a power reception side circuit (any one of 71a to 71d) corresponding to the power reception coil (any one of RC1 to RC4) coupled to the connected power transmission coil. At this time, the switches SW1b to SW8b in the second power transmission circuit 600b are all controlled to be off.

When switching between the operating state and the standby state, all of the switches SW1a to SW8a in the first power transmission circuit 600a are turned off. The second power transmission circuit 600b controls on/off of the switches SW1b to SW8b so that the power transmission circuit 61b is connected to any one of the power transmission coils TC1b, TC2b, TC3b, and TC4b. As a result, the power transmission side circuit 61b exchanges information with the power reception side circuit (any one of 71a to 71d) corresponding to the power reception coil (any one of RC1 to RC4) coupled to the connected power transmission coil.

According to the battery monitoring device of FIG. 21, since the information transmission path is duplicated, even if one circuit fails, the other circuit can still operate. As a result, a highly reliable device can be realized.

In addition, since all selection switches of the power transmission side circuit of the standby system are controlled to be off, nothing is connected to the power transmission side circuit of the standby system. As a result, the influence of the power transmission side circuit of the standby system on the transmission operation of the power transmission side circuit of the active system can be reduced, and information can be exchanged with higher reliability.

Also, since the magnetic field coupling portion is duplicated, there is little interference between the active system and the standby system.

In addition, since the power transmission side circuit of the active system and the power transmission side circuit of the standby system can be identified by the ID of NFC communication or the like, it is possible to reliably detect an abnormality such as disconnection or connection error.

In addition, this invention is not limited to the said embodiment. For example, in the above embodiment, an example using a high frequency magnetic field of 13.56 MHz has been described, but magnetic fields of frequencies in different frequency bands such as 100 kHz and 6.78 MHz may be used. Alternatively, an electromagnetic field of several hundred MHz may be used. By designing a power transmitting antenna (transmitting coil) and a power receiving antenna (power receiving coil) suitable for each frequency, it is possible to configure a device that performs similar operations using magnetic or electromagnetic fields of these frequencies.

The configurations of the signal transmission device and the battery monitoring device of the present invention can also be used for high voltage devices other than battery monitoring and power line monitoring.

Further, the position of the transmitting side and the position of the receiving side may be changed, and the configuration may be such that the power transmitting coil and the power receiving coil rotate relative to each other. Also, the power transmission side and the power reception side may be configured to be detachable.

Further, the signal transmission device and the battery monitoring device of the present invention may be operated in environments such as water, oil, and outer space.

Also, the power transmission coil and the power reception coil may be subjected to waterproof treatment or airtight treatment. Alternatively, a magnetic sheet may be used to magnetically shield between the power transmitting coil and the power receiving coil and the outside. A filter that suppresses harmonics may also be used.

Further, in the above third and fourth embodiments, an example of a battery monitoring device that monitors four battery cells has been described. However, the number of battery cells is not limited to this, as long as it is configured as a battery monitoring device that monitors n battery cells (where n is an integer equal to or greater than 2). In that case, the number of power transmitting coils, power receiving coils, and power receiving side circuits should be n.

100 operating device 200 power receiving circuit 300 power transmitting circuit 400 signal transmission device 500, 800 battery monitoring device 600 power transmitting circuit 700 power receiving circuit 10 high voltage circuit 11 transformer 12 rectifier circuit 13 low voltage circuit 14 measurement circuit 20 power receiving side circuit 21 resonance circuit 22 rectification Circuit 23 Power supply and bias circuit 24 Power supply circuit 25 Bias circuit 26 Communication circuit 27 Control circuit 28 Clamp circuit 30 Power transmission side circuit 31 AC signal source 32 Drive circuit 33 Control circuit 34 Communication circuit 35 Resonance circuit 36 Current measurement circuit 61 Power transmission side circuit 71a ~71d Power receiving side circuit 72a~72d Battery cell

Claims (6)

an operation circuit that operates based on a first voltage from a power supply; a measurement circuit that measures an electrical signal based on the first voltage to obtain measurement data; and a processing control circuit that operates based on a second voltage obtained by converting the voltage to a lower level and that controls the operation of the operation circuit based on the measurement data. a power transmission circuit for performing
It has a power transmission side resonance circuit consisting of a power transmission coil and a power transmission side resonance capacitor, transmits power from the processing control circuit in a non-contact manner by an alternating magnetic field from the power transmission coil, and transmits the measurement data via the power transmission coil. A power transmission circuit for receiving and supplying to the processing control circuit of the operating device. a drive circuit that supplies a drive current to the power transmission coil to generate an alternating magnetic field;
a drive control circuit that controls the drive circuit;
further having
The drive circuit includes a current measurement circuit that measures the drive current,
2. The power transmission circuit according to claim 1, wherein the drive control circuit controls the drive circuit based on the measurement result of the current measurement circuit. The power transmission coil is
a wiring portion arranged in a first wiring layer of a substrate having a plurality of wiring layers, the wiring portion being composed of a continuous conductor wire having one end connected to the power transmission side resonance capacitor;
a spiral-shaped continuous conductor having first and second ends, the first end being connected to the power transmission side resonance capacitor, and arranged on the first wiring layer; a spiral portion having a conductor portion that traverses between an end of the wire portion and the other end of the wiring portion;
a continuous conductor portion disposed on a second wiring layer of the substrate; and via a pair of vias provided between the first wiring layer and the second wiring layer. a connecting portion connecting the end of the wiring portion and the other end of the wiring portion;
3. The power transmission circuit according to claim 1 or 2, characterized by comprising: an operation circuit that operates based on a first voltage from a power supply; a measurement circuit that measures an electrical signal based on the first voltage to obtain measurement data; and a processing control circuit that operates based on a second voltage obtained by converting the voltage to a lower level and that controls the operation of the operation circuit based on the measurement data. a power receiving circuit that performs
It has a power receiving side resonance circuit consisting of a power receiving coil and a power receiving side resonance capacitor, and supplies power transmitted contactlessly to the power receiving coil by an alternating magnetic field to the measurement circuit, while receiving the measurement data obtained from the measurement circuit. A power receiving circuit characterized by transmitting. 5. The power receiving circuit according to claim 4, further comprising a load switching circuit capable of switching the state of the load connected to said power receiving resonance circuit according to a load switching signal. The receiving coil is
a wiring portion arranged in a first wiring layer in a substrate having a plurality of wiring layers, the wiring portion being composed of a continuous conductive wire having one end connected to the power receiving side resonance capacitor;
a spiral-shaped continuous conductive wire having first and second ends, the first end being connected to the power receiving side resonance capacitor, and arranged on the first wiring layer ; a spiral portion having a conductor portion that traverses between an end of the wire portion and the other end of the wiring portion;
a continuous conductor portion disposed on a second wiring layer of the substrate; and via a pair of vias provided between the first wiring layer and the second wiring layer. 6. The power receiving circuit according to claim 4, further comprising a connecting portion that connects the end of the wiring portion to the other end of the wiring portion.

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