KR20080095645A - Wiress charger and battery charging sethaving the same - Google Patents

Abstract

A contactless charger and a battery charging set having the same are provided to prevent damage due to the overvoltage applied to both ends of a constant voltage/constant current supplier by controlling a charging power in real time through wireless feedback control. A power supply(240) receives a commercial AC, converts the AC into the DC, and supplies the DC. A charging power supply(250) converts the power from the power supply into the power for charging and supplies the converted power. A high frequency power driver applies a high frequency AC to a magnetic field generator intermittently by using the power from the charging power supply. The magnetic field generator receives the high frequency AC from the high frequency power driver and forms the magnetic field at an outer space. A charging power controller(260) controls the charging power supply by receiving the monitored result through wireless communication while the high frequency AC is not applied to the magnetic field generator and controls the charging power delivered to the battery by controlling the power of the high frequency AC applied to the magnetic field generator.

Description

Contactless charger and battery charging set including same {Wiress charger and Battery charging sethaving the same}

The following drawings attached to this specification are illustrative of preferred embodiments of the present invention, and together with the detailed description of the invention to serve to further understand the technical spirit of the present invention, the present invention is a matter described in such drawings It should not be construed as limited to

1 is a schematic block diagram of a charger and a battery employing a conventional contactless charging method.

Figure 2 is a perspective view of a combined electric toothbrush employing a conventional contactless charging method.

3 is a block diagram schematically showing the configuration of the contactless charger (C) and the battery (B) according to a preferred embodiment of the present invention.

<Description of main reference numerals in the drawings>

C ... contactless charger 200 ... primary coil

High frequency power generator 210 220 Primary antenna

230 ... unbrided bride 240 ... power supply

241 ... overvoltage protection circuit 242 ... rectifier

250 ... charging power supply unit 251 ... pulse signal generator

252 Constant voltage supply 260 Charge power control

300 ... secondary coil 310 ... rectifier

320 ... constant voltage / constant current supply unit (320) 330 ... monitoring unit

340 Wireless Transmitter 350 Antenna

360 ... Charge pause detector 400 ... Battery cell

The present invention relates to an apparatus for charging a battery in a contactless manner using an electromagnetic induction phenomenon, and a battery charging set having the same, and more particularly, to monitor power supplied for battery charging and to perform wireless feedback control. A contactless charger and a battery charging set having the same.

Personal portable devices such as mobile phones, PDAs, notebooks, etc., are powered by rechargeable batteries. When the user of the personal portable device falls below a predetermined level, the user of the portable device charges the battery using a charger and then uses the battery again.

A battery of a general personal portable device has an externally exposed connection terminal to be electrically connected to a charging terminal provided in a charger. When the battery is charged, the charging terminal of the charger and the connection terminal of the battery are connected to each other to maintain an electrically connected state.

However, since the charging terminal and the connection terminal are exposed to the outside for mutual connection, they are easily contaminated by foreign substances, and wear occurs due to friction between both terminals in the process of connecting the charging terminal and the connection terminal, and moisture in the air. This causes a problem that the connection between the charging terminal and the connection terminal becomes poor due to corrosion of the charging terminal and the connection terminal. If moisture penetrates into the battery through the minute gap of the connection terminal during the use of the battery, a fatal problem of completely discharging the battery is caused by a short circuit of the internal circuit.

In order to solve this problem, a contactless charging technology has recently been proposed to charge a battery in a state where a battery of a personal portable device is coupled with a charger in a contactless manner by an electromagnetic induction phenomenon. Contactless charging technology is now widely used in everyday products such as electric toothbrushes and electric shavers.

1 schematically shows a configuration of a battery and a charger employing a contactless charging method according to the prior art.

Referring to FIG. 1, the charger 10 receives power from a commercial AC power source 20 and outputs a high frequency AC current, and a high frequency AC current from the high frequency power composition means 30. It is provided with a primary coil 40 that is applied to form a magnetic field (M).

In addition, the battery 50 may include a battery cell 60 in which electrical energy is charged, a secondary side coil 70 in which a high frequency alternating current is induced according to a linkage of the magnetic field M generated in the primary side coil 40, and a secondary side. A rectifier 80 converts the high frequency AC current induced by the coil 70 into a DC current, and a constant voltage / constant current supply unit 90 that applies the DC current rectified by the rectifier 80 to the battery cell 60.

Here, the constant voltage / constant current supply unit 90 is a known circuit element widely used in a battery charging device. The constant voltage / constant current supply unit 90 supplies a constant current to the battery cell 60 at the initial stage of charging, but gradually increases the charging voltage of the battery cell 60 to reduce the supply of current when the voltage exceeds the predetermined reference value. It keeps the function constant.

According to the charger 10 and the battery 50 employing the conventional contactless charging method described above, the magnitude of the high-frequency alternating current induced in the secondary side coil 70 is determined by the magnetic flux that crosses the secondary side coil 70. Proportional to size. Then, the magnitude of the magnetic flux chained to the secondary side coil 70 changes depending on the relative position with the primary side coil 40. That is, as the secondary coil 70 is located closer to the primary coil 40 of the charger 10, the magnitude of the magnetic flux that links to the secondary coil 70 increases, and as a result, the secondary coil 70 ) Also increases the magnitude of high-frequency AC current.

Meanwhile, the standard of the constant current / constant voltage supply unit 90, which is a core element of the charging circuit module included in the contactless rechargeable battery 50, is defined according to the magnitude of the high frequency AC current induced by the secondary coil 70. However, as described above, the magnitude of the alternating current induced in the secondary coil 70 varies depending on the relative positions of the primary coil 40 and the secondary coil 70.

Therefore, if the standard of the constant current / constant voltage supply unit 90 is defined by a small high frequency AC current, the battery 10 is charged when the battery 50 is positioned at a point where a relatively large high frequency AC current is induced. In the process, overvoltage is applied to both ends of the constant current / constant voltage supply unit 90 may cause a problem that the component is burned out.

In view of the above, the charger 10 and the battery 50 employing the conventional contactless charging method have a structure capable of relatively fixing the position of each other at a point defining the standard of the constant current / constant voltage supply unit 90. It is common to adopt.

2 is a perspective view of the electric toothbrush 100 employing a conventional contactless charging method.

Referring to FIG. 2, the electric toothbrush 100 includes a toothbrush body 110 equipped with a battery 115 at a lower end thereof, and a charger 120 charging the battery 115 in a contactless manner. The lower end of the toothbrush body 110 is provided with a main groove 130 and the auxiliary groove 140, the upper portion of the charger 120 has a shape that is matched to the main groove 130 and the auxiliary groove 140. The main protrusion 150 and the auxiliary protrusion 160 are provided, respectively.

The toothbrush body 110 and the charger 120 are tightly fixed by the matching of the grooves 130 and 140 and the protrusions 150 and 160. As a result, the battery 115 and the charger provided in the toothbrush body 110 are fixed. The relative position of 120 is also tightly fixed.

The standard of the constant voltage / constant current supply unit 170 provided in the battery 115 is defined assuming a state in which the toothbrush body 110 and the charger 120 are closely coupled. Therefore, an overvoltage greater than the specification is not applied to both ends of the constant voltage / constant current supply unit 170, and as a result, it is possible to prevent the constant voltage / constant current supply unit 170 from being burned out due to an unexpected overvoltage.

However, if the relative position of the battery 115 and the charger 120 is strictly restricted as described above, there is a problem that causes inconvenience to the user. That is, the user must suffer the trouble of repeatedly making efforts to fix the toothbrush body 110 at a predetermined position with respect to the charger 120 whenever the battery 115 provided in the toothbrush body 110 is charged. . Therefore, in order to maximize the user's convenience, it is necessary to propose a new technical alternative that can overcome the relative position constraints of the battery 115 and the charger 120.

The present invention was devised to solve the above-mentioned problems of the prior art, and can solve the relative positional constraint between the battery and the charger while charging the battery by a non-contact charging method, and can prevent damage to the internal circuit of the battery. It is an object of the present invention to provide a contactless charging charger and a battery charging set including the same.

In order to achieve the above object, the contactless charger according to an aspect of the present invention may be charged in a constant voltage / constant current mode having a constant voltage / constant current supply unit and wirelessly transmit a monitoring result for voltages at both ends of the constant voltage / constant current supply unit. A contactless charger for delivering charging power by electromagnetic induction to a contactless rechargeable battery, comprising: a power supply configured to receive a commercial AC current and convert it into a DC power supply; A charging power supply unit converting power supplied from the power supply unit into power required for charging and supplying the power; A high frequency power driver for intermittently applying a high frequency AC current to the magnetic field generating unit by using the power supplied from a charging power supply unit; A magnetic field generator for receiving a high frequency AC current from the high frequency power driver to form a magnetic field in an external space; While the high frequency AC current is not applied to the magnetic field generating unit, the monitoring result is received through wireless communication, and the charging power supply unit is controlled to adjust the power of the high frequency AC current applied to the magnetic field generating unit to transfer to the battery side. It includes; a charging power control unit for adjusting the charging power.

The magnetic field generating unit may be a coil to which a high frequency AC current is applied to both ends.

The charging power control unit includes a wireless receiving unit for receiving the monitoring result through the antenna; And a microprocessor that receives the monitoring result from the wireless receiver and controls the charging power supply to adjust the power applied to the high frequency power generator.

The charging power supply unit receives a pulse driving signal from the microprocessor and outputs a pulse signal; And a constant voltage supply unit modulating the magnitude of the voltage input from the power supply unit in consideration of the pulse signal and supplying the same to the high frequency power generator.

The power supply unit is an overvoltage blocking protection circuit for receiving a commercial AC current to block the overvoltage current; And a rectifying unit rectifying the AC current passing through the protection circuit and converting the AC current into a DC current.

The charging power controller generates a control signal for modulating the width of the pulse current, the frequency of the pulse current, the amplitude of the pulse or the number of pulses.

In a battery charge set including a battery charge set contactless rechargeable battery and a contactless charger according to another aspect of the present invention, the battery is inductively induced by a high frequency alternating current by a magnetic field generated by an external contactless charger. A high frequency AC current induction unit, a rectifying unit receiving the induced high frequency AC current into a DC current, a constant voltage / constant current supply unit receiving DC current from the rectifying unit and supplying charging power to a battery cell in a constant voltage-constant current mode; And a monitoring unit which monitors the charging power supplied to the battery cell and transfers the monitoring result to an external contactless charger through wireless communication while the induction of the high frequency AC current is not performed. To convert the DC power supply A high frequency source intermittently applying a high frequency alternating current to the magnetic field generating unit by using a source supply unit, a charging power supply unit converting the power supplied from the power supply unit into power required for charging, and a power supplied from the charging power supply unit The magnetic field generating unit receives a high frequency AC current from the high frequency power driving unit, and forms a magnetic field in an external space, and transmits the monitoring result through wireless communication while the high frequency AC current is not applied to the magnetic field generating unit. And a charging power controller configured to adjust the charging power delivered to the battery by controlling the charging power supply unit to adjust the power of the high frequency AC current applied to the magnetic field generating unit.

The magnetic field generating unit is a coil to which a high frequency alternating current is applied to both ends, and the high frequency alternating current inducing unit is a coil in which magnetic flux of the magnetic field generated from the magnetic field generating unit crosses.

The monitoring unit wireless transmission unit for wirelessly propagating the monitoring results through the antenna; First and second voltage detectors detecting voltages at the front and rear ends of the constant voltage / constant current supply unit, respectively; And a microprocessor that checks the first and second voltages detected by the first and second voltage detectors, and outputs a corresponding monitoring result to the wireless transmitter.

The monitoring unit may further include a voltage comparator configured to compare the first and second voltages detected by the first and second voltage detectors to output a voltage comparison result.

The monitoring unit wireless transmission unit for wirelessly propagating the monitoring results through the antenna; A current detector for measuring a current value supplied from the constant voltage / constant current supply unit to the battery cell; And a microprocessor for outputting a monitoring result to the wireless transmitter in consideration of the current value detected by the current detector.

The magnetic field generated by the contactless charger is intermittently generated, and the monitoring unit receives a high frequency alternating current output from the high frequency alternating current induction unit and detects a point at which the induction of the high frequency alternating current is terminated and outputs it to the microprocessor. The charging stop detection unit further includes, and the monitoring result may be transmitted to an external contactless charger through wireless communication while the induction of the high frequency AC current is not performed after the time point is input.

The monitoring result may be a code indicating that a charge power adjustment request signal or a voltage difference between both ends of the constant voltage / constant current supply unit, both voltage values, or both voltages are in an overvoltage state.

The magnetic field generating unit is a coil to which a high frequency AC current is applied to both ends.

The charging power control unit includes a wireless receiving unit for receiving the monitoring result through the antenna; And a microprocessor that receives the monitoring result from the wireless receiver and controls the charging power supply to adjust the power applied to the high frequency power generator.

The charging power supply unit receives a pulse driving signal from the microprocessor and outputs a pulse signal; And a constant voltage supply unit modulating the magnitude of the voltage input from the power supply unit in consideration of the pulse signal and supplying the modulated voltage to the high frequency power generator.

The power supply unit is an overvoltage cut-off filter unit for receiving a commercial AC current to block the overvoltage current; And a rectifying unit rectifying the alternating current passing through the filter unit and converting the alternating current into a direct current.

The charging power control unit preferably generates a control signal for modulating the width of the pulse current, the frequency of the pulse current, the amplitude of the pulse or the number of pulses.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms or words used in the specification and claims should not be construed as having a conventional or dictionary meaning, and the inventors should properly explain the concept of terms in order to best explain their own invention. Based on the principle that can be defined, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention. Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

3 is a block diagram schematically showing the configuration of the contactless charger (C) and the battery (B) according to a preferred embodiment of the present invention.

Referring to FIG. 3, the contactless charger C according to an exemplary embodiment of the present invention may include a primary coil 200, a high frequency power generator 210, a primary antenna 220, a wireless receiver 230, and a charging unit. It includes a power control unit 260, a charging power supply unit 250, and a power supply unit 260.

The high frequency power generator 210 generates a magnetic field by applying a high frequency AC current of several tens of KHz to the primary coil 200 through a high speed switching operation. For example, the high frequency power generator 210 applies a high frequency AC current of 80 KHz to the primary coil 200. When the magnetic field is generated by the high frequency AC current in the primary coil 200, the charging power is transmitted to the battery B side in a contactless manner by the electromagnetic induction phenomenon. At this time, the frequency of the high frequency AC current generated by the high frequency power generator 210 is fixedly output.

Preferably, a known switching mode power supply (SMPS) may be employed as the high frequency power generator 210, but the present invention is not limited thereto.

The wireless receiver 230 receives an adjustment request signal for charging power wirelessly transmitted from the battery B side through the antenna 220 and inputs it to the charging power controller 260.

The adjustment request signal is a signal that is transmitted when excessive charging power is delivered to the battery side and there is a risk of burnout of a circuit component supplying a constant voltage / constant current. The adjustment request signal is modulated and transmitted from the battery B side. Therefore, the wireless receiver 230 demodulates the adjustment request signal and inputs it to the charging power control unit 260.

Preferably, carriers in the 10-15 MHz band are used for the wireless transmission of the coordination request signal. The wireless receiver 230 is configured using a photo coupler. However, the present invention is not limited to the frequency band of the carrier and the type of device for configuring the wireless receiver 230.

When the adjustment request signal is wirelessly transmitted from the battery B side, it is preferable that a high frequency AC current is not applied to the primary coil 200. When the adjustment request signal is wirelessly transmitted in a state in which a magnetic field is generated in the primary coil 200 by application of a high frequency alternating current of several tens of KHz bands, the adjustment request signal is screened by the magnetic field and the adjustment request is made through the wireless receiver 230. This is because the signal is not received properly.

Therefore, the high frequency power generator 210 does not continuously apply the high frequency AC current to the primary side coil 200 but periodically gives a rest period. For example, the high frequency power generator 210 does not apply a high frequency AC current to the primary coil 200 for 50 ms every 3 seconds when the charging power is transferred to the battery B side. In this case, the adjustment request signal is wirelessly transmitted within 50 ms in which the high frequency AC current is not applied to the primary coil 200.

The power supply unit 240 receives the commercial power, converts it into a DC current, and transfers it to the charging power supply unit 250. In detail, the power supply unit 240 includes an overvoltage blocking protection circuit 241 for blocking overvoltage applied from commercial power, and a rectifying unit 242 for converting and supplying an AC voltage passed through the overvoltage blocking protection circuit 241 to a DC voltage. ).

The charging power supply unit 250 converts the DC current received from the rectifying unit 242 to generate power of a size necessary for the high frequency power generator 210 to generate a high frequency AC current. Specifically, the charging power supply unit 250 receives a pulse driving signal from the charging power control unit 260 to generate a pulse signal and a pulse signal output from the pulse signal generator 251. By switching the DC voltage input from the rectifying unit 242 at a high speed includes a constant voltage supply unit 252 that can modulate the magnitude of the DC voltage to the size as desired by the charging power control unit 260.

The charging power control unit 260 controls the overall operation of the charger (C), in particular, when the adjustment request signal of the charging power received from the wireless receiver 230 controls the charging power supply unit 250 to control the high frequency power generator 210 ) Adjusts the power of the high frequency AC current applied to the primary coil 200. That is, the charging power control unit 260 modulates the width of the pulse supplied to the charging power supply unit 250, modulates the frequency of the pulses, or modulates the number of pulses. By modulating or modulating the amplitude of the pulse, the charge power supply unit 250 adjusts the amount of power supplied to the charge power supply unit 210 supplying the charge power at a constant frequency. Then, the level of the charging power delivered to the battery B side is adjusted to prevent damage to the circuit inside the battery B.

The contactless battery B according to the embodiment of the present invention includes a charging circuit module including a secondary coil 300, a rectifying unit 310, a constant voltage / constant current supply unit 320, and a monitoring unit 330, and the charging unit. The battery cell 400 is charged by the circuit module.

The secondary coil 300 generates a high frequency AC current by an electromagnetic induction phenomenon while a high frequency AC current is applied to the primary coil 200 provided in the charger C. At this time, the magnitude of the high frequency alternating current induced in the secondary coil 300 is proportional to the magnetic flux chained to the secondary coil 300.

The rectifier 310 smoothes the high frequency AC current induced by the secondary coil 300 and converts the DC current into smooth current.

The constant voltage / constant current supply unit 320 charges the battery cell 400 by applying the rectified DC current to the battery cell 400 under the control of the monitoring unit 330, but initially charges the battery cell 400 in the constant current mode. ) And charges the battery cell 400 in a constant voltage mode that maintains the charging voltage constant instead of reducing the current when the charging voltage exceeds a predetermined reference.

The monitoring unit 330 controls the constant voltage / constant current supply unit 320 to charge the battery cell 400, monitors whether excessive voltage is applied to both ends of the constant voltage / constant current supply unit 320, and charges when the excessive voltage is applied. The power request signal adjustment is transmitted to the wireless receiver 230 of the charger (C).

Preferably, the monitoring unit 330 is the first voltage detection unit 331 respectively provided at the front and rear ends of the constant voltage / constant current supply unit 320 to monitor whether the overvoltage is applied to both ends of the constant voltage / constant current supply unit 320 And the first voltage V _pp and the second voltage V _ch measured by the second voltage detector 332, the first voltage detector 331, and the second voltage detector 332, respectively. A microprocessor 335 which determines whether an overvoltage is applied and generates an adjustment request signal for charging power, and a wireless transmitter 336 and an antenna which wirelessly transmits a signal output from the microprocessor 335 to the charger C. (337).

Furthermore, as described above, the microprocessor 335 compares the first voltage V _pp and the second voltage V _ch measured by the first voltage detector 331 and the second voltage detector 332, respectively. Although it is possible to generate the adjustment request signal of the charging power, as an alternative thereto, the monitoring unit 330 is a first voltage (measured by the first voltage detector 331 and the second voltage detector 332, respectively) It may further include a voltage comparison unit 333 for inputting the comparison result of V _pp ) and the second voltage (V _ch ) to the microprocessor 335. In addition, the microprocessor 335 may generate an adjustment request signal for charging power with the result value input from the voltage comparator 333.

On the other hand, if it is determined that the overvoltage is being applied as a result of monitoring the voltage across the constant voltage / constant current supply unit 320, the microprocessor 335 uses the wireless transmitter 336 to charge the adjustment request signal of the charging power through the charger (C) to the side.

The wireless transmitter 336 receives the adjustment request signal of the charging power output from the microprocessor 335, modulates the adjustment request signal, and provides the wireless receiver 230 provided at the charger C side through the antenna 337. Wireless transmission to the antenna 220. At this time, a carrier of the 10 ~ 15MHz band is used, the wireless transmitter 336 is implemented by a photo coupler like the wireless receiver 230.

When the adjustment request signal is transmitted to the charger C side, the high frequency AC power output through the charging power supply unit 250 and the high frequency power generation unit 210 under the control of the charging power control unit 260 is reduced. As a result, the power of the high frequency AC current induced in the secondary coil 300 by the electromagnetic induction phenomenon decreases. Accordingly, the voltage applied to both ends of the constant voltage / constant current supply unit 320 also decreases. Preferably, the feedback control for the power of the high frequency AC current applied to the primary coil 200 is continued until no overvoltage is applied to both ends of the constant voltage / constant current supply unit 320.

However, when the adjustment request signal is wirelessly propagated while the charging power is being transferred from the primary coil 200 of the charger C to the secondary coil 300 of the battery B, the primary coil 200 is discharged from the primary coil 200. A problem arises in that the adjustment request signal is screened by the generated magnetic field.

Therefore, the present invention temporarily stops the transfer of the charging power at regular intervals when the charging power is transferred from the charger C to the battery B in order to solve the above problem.

That is, as shown in Figure 4, the high-frequency alternating current is induced to the secondary coil 300 by the electromagnetic induction phenomenon, the charging section (Δt _A ) and the high-frequency alternating current for the primary coil 200 The application of the current is intentionally paused to periodically repeat the period Δt _B where charging is stopped. In addition, while the induction of the high frequency AC current is stopped in the secondary coil 300, the charging request signal of the charging power is transmitted to the charger C while the charging is stopped.

To this end, the battery B according to an embodiment of the present invention receives a high-frequency AC current induced from the secondary coil 300 to detect a time point at which the charging section ends (see t _{s in} FIG. 6). 340.

The charge stop detection unit 340 detects an end point of charging section (see t _{s in} FIG. 6) and inputs it to the microprocessor 335. Then, the microprocessor 335 wirelessly transmits the adjustment request signal for adjusting the charging power to the charger C through the wireless transmitter 336 while the charging power is not transmitted. Therefore, the adjustment request signal of the charging power can be prevented from being screened by the magnetic field generated by the primary coil 200.

When the charge request for adjusting the charging power is wirelessly transmitted to the charger C, the high frequency AC power applied to the primary coil 200 is adjusted by the feedback control as described above, thereby providing both ends of the constant voltage / constant current supply unit 320. The voltage can be maintained at an appropriate level.

In the contactless charger and the battery according to the present invention described above, even if an overvoltage is applied to both ends of the constant voltage / constant current supply unit 320, the overvoltage state can be immediately resolved by reducing the charging power in real time through feedback control.

Therefore, the contactless charger and the battery of the present invention do not need to be fixed relative positions of each other as in the prior art in order to maintain a constant magnitude of the magnetic flux chained to the secondary coil 300, as shown in FIG. As described above, the charger C is manufactured in a pad shape so that the user can conveniently charge the battery by simply placing a charging object such as a mobile phone in which the battery B is coupled to a predetermined position of the pad. Can be produced.

Furthermore, the monitoring unit 330 may further include a current detector 334 measuring a current value supplied to the battery cell 400, and the microprocessor 335 may measure the current value measured through the current detector 334. By checking whether the reference current value is exceeded, it is possible to confirm that an overcurrent is applied to the battery cell 400 and to prevent it. To this end, the microprocessor 335 may further include a result of determining the occurrence of the overcurrent in the adjustment request signal for adjusting the charging power. In addition, the charging power controller 260 may check whether the overcurrent is supplied through the adjustment request signal for adjusting the charging power, and feedback control the power of the high frequency AC current applied to the primary coil 200.

Hereinafter, the operation of the battery charge set according to the present invention will be described in detail with reference to the above-described components.

First, in the non-charging mode, the charging power supply unit 250 of the charger C transmits a voltage having a predetermined size to the high frequency power generation unit 210 under the control of the charging power control unit 260, and the high frequency power generation unit ( The 210 applies a high frequency AC current to the primary coil 200 at regular time intervals. For example, a high frequency AC current of 80 KHz is applied for 50 ms at 1 second intervals. Then, the primary coil 200 forms a magnetic field around each time a high frequency alternating current is applied.

The user places the battery B on the charger C for charging the battery B. After the battery B is positioned, when a high frequency alternating current is applied to the primary coil 200 of the charger C for a predetermined time, a magnetic field is generated in the primary coil 200, and as a result, the battery B The magnetic flux is chained to the secondary coil 300 of the. Accordingly, in the secondary coil 300, the high frequency AC current is induced for a predetermined time, but when the high frequency AC current is not applied to the primary coil 200, the induction of the high frequency AC current is suspended due to the disappearance of the magnetic field.

On the other hand, the charge stop detection unit 340 detects the time when the induction of the high frequency AC current is suspended and inputs to the microprocessor 335. In response, the microprocessor 335 outputs a response signal to the wireless transmitter 336. Here, the response signal is a state in which the secondary coil 300 of the battery B is coupled to the magnetic field generated by the primary coil 200 on the charger C side. 260). When the response signal is output to the wireless transmitter 336, the wireless transmitter 336 modulates the response signal and wirelessly transmits the response signal to the charger C through the antenna 337.

When the response signal is transmitted wirelessly, the wireless receiver 230 of the charger C demodulates the response signal and inputs it to the charging power controller 260. Then, the charging power control unit 260 starts to transfer the charging power to the battery B side. That is, the charging power controller 260 controls the high frequency power generator 210 to apply the high frequency alternating current to the primary coil 200 for a predetermined time interval and to stop the application of the high frequency alternating current for a predetermined time. Repeat. For example, a high frequency alternating current of 80 KHz is applied for 3 seconds and then rested for 50 ms.

While the high frequency AC current is applied to the primary coil 200, the high frequency AC current is also induced in the secondary coil 300 of the battery B by the electromagnetic induction phenomenon. The duration of induction of the high frequency AC current is substantially the same as that of the application of the high frequency AC current to the primary coil 200.

The high frequency AC current induced in the secondary coil 300 is converted into a DC current by the rectifier 320 and then applied to the battery cell 400 via the constant voltage / constant current supply unit 320. Then, as the battery cell 400 is gradually charged, the voltage of both ends of the battery cell 400 rises until it is fully charged.

The microprocessor 335 controls the constant voltage / constant current supply unit 320 to charge the battery cell 400 in the constant current mode until the charging voltage of the battery cell increases to a certain level, and then the voltage of the battery cell 400 is at a predetermined level. If more than this, the battery cell 400 is charged in the constant voltage mode.

Meanwhile, when the high frequency AC current applied to the primary side coil 200 is stopped, charging of the secondary side coil 300 is temporarily stopped while induction of the high frequency AC current is temporarily stopped. Then, the charge stop detection unit 340 detects a time point at which the induction of the high frequency AC current is stopped and inputs it to the microprocessor 335. This operation is repeatedly performed every time the induction of the high frequency AC current is suspended.

Apart from the charging process of the battery cell 400 as described above, the microprocessor 335 monitors whether an overvoltage is applied to both ends of the constant voltage / constant current supply unit 320.

To this end, the voltage comparison unit 333 periodically receives the voltage measured by the first voltage detector 350 and the second voltage detector 360 provided at the front and rear ends of the constant voltage / constant current supply unit 320. The values are compared with each other and the voltage comparison result is input to the microprocessor 335. Here, the voltage comparison result is a voltage state signal indicating whether or not the difference between the two voltages measured or an overvoltage state.

The microprocessor 335 receives the voltage comparison result from the voltage comparing unit 333, and then determines whether the overvoltage is applied to both ends of the constant voltage / constant current supply unit 320.

As a result, when it is determined that the overvoltage is applied to both ends of the constant voltage / constant current supply unit 320, the microprocessor 335 refers to the time point at which the induction of the high frequency AC current input by the charge stop detection unit 340 is temporarily stopped. It is determined whether or not the high frequency induction current is not applied to the primary coil.

As a result, when it is determined that it is the idle period, the microprocessor 335 outputs the adjustment request signal of the charging power to the wireless transmitter 336. Then, the wireless transmitter 336 modulates the adjustment request signal for charging power and wirelessly transmits the charge to the charger C through the antenna 337.

In response to this, the wireless receiver 230 provided in the charger C receives and demodulates the adjustment request signal of the charging power through the antenna 220 and inputs it to the charging power controller 260. Then, the charging power control unit 260 controls the magnitude of the charging voltage output from the charging power supply unit 250 to determine a predetermined level of high frequency AC power applied to the primary coil 200 through the high frequency power generating unit 210. Lower as much as

When the high frequency AC power applied to the primary coil 200 is reduced as described above, the power of the high frequency AC current induced to the secondary coil 300 by electromagnetic induction also decreases.

On the other hand, apart from the feedback control for the power of the high frequency AC current, the monitoring operation for the overvoltage state across the constant voltage / constant current supply unit 320 by the microprocessor 335 is periodically repeated. As a result, if it is determined that the overvoltage state across the constant voltage / constant current supply unit 320 is still not resolved through the primary feedback control, the microprocessor 335 wirelessly transmits the adjustment request signal for charging power to the charger C side. The power of the high frequency AC current applied to the primary side coil 200 is once again reduced again by a predetermined level. This process continues until no overvoltage is applied across the constant voltage / constant current supply unit 320 through feedback control.

By maintaining the voltage difference across the constant voltage / constant current supply unit 320 at an appropriate level through the feedback control as described above, the constant voltage / constant current supply unit 320 is caused by an overvoltage in the process of charging the battery B in a contactless manner. The burnout can be prevented.

In the above-described embodiment of the present invention, the microprocessor 335 on the side of the battery B has a constant voltage / constant current to prevent an overvoltage from being applied to both ends of the constant voltage / constant current supply unit 320 of the contactless rechargeable battery B. The voltage measured at both ends of the supply unit 320 is monitored to check whether the voltage is directly in an overvoltage state. If the overvoltage state corresponds to the microprocessor 335 of the battery B, the charging power adjustment request signal is transmitted to the charging power controller 260 of the charger C side through wireless communication. Then, the charging power control unit 260 of the charger C side adjusts the charging voltage level of the charging power supply unit 250 under the condition of receiving the charging power adjustment request signal, and applies the high frequency AC current applied to the primary coil 200. To adjust the power.

If the adjustment process of the charging current as described above is repeated as necessary, even if the overvoltage is applied to both ends of the constant voltage / constant current supply unit 320 can be prevented that the constant voltage / constant current device 320 is burned out by being resolved in a fast time. have.

Although the present invention has been described above by means of limited embodiments and drawings, the present invention is not limited thereto and will be described below by the person skilled in the art to which the present invention pertains. Of course, various modifications and variations are possible within the scope of the claims.

According to the present invention, even if overvoltage is applied to both ends of the constant voltage / constant current supply unit during the charging process of a contactless battery, the constant voltage / constant current supply unit is damaged by the overvoltage applied to both ends by adjusting the charging power in real time by wireless feedback control. It can prevent.

Accordingly, in the charger and the battery employing the contactless charging method, the relative positional constraints of each other can be overcome, and as a result, user convenience can be maximized.

Claims (19)

The contactless charger which is equipped with a constant voltage / constant current supply unit which can be charged in a constant voltage / constant current mode and wirelessly transmits the monitoring results of the voltages on both ends of the constant voltage / constant current supply unit to deliver charging power by electromagnetic induction phenomenon. To A power supply unit which receives commercial AC current and converts the power into DC power; A charging power supply unit for converting and supplying the power supplied from the power supply unit to the power required for charging; A high frequency power driver for intermittently applying a high frequency AC current to the magnetic field generating unit by using the power supplied from a charging power supply unit; A magnetic field generator for receiving a high frequency AC current from the high frequency power driver to form a magnetic field in an external space; And While the high frequency AC current is not applied to the magnetic field generating unit, the monitoring result is received through wireless communication, and the charging power supply unit is controlled to adjust the power of the high frequency AC current applied to the magnetic field generating unit, thereby being transferred to the battery side. Contactless charger comprising a; charging power control unit for adjusting the charging power. The method of claim 1, The magnetic field generating unit is a contactless charger, characterized in that the coil is applied to the high frequency AC current at both ends. The method of claim 1, The charging power control unit, A radio receiver which receives the monitoring result through an antenna; And And a microprocessor which receives the monitoring result from the wireless receiver and controls the charging power supply to adjust the power applied to the high frequency power generator. The method of claim 3, The charging power supply unit A pulse signal generator for receiving a pulse driving signal from the microprocessor and outputting a pulse signal; And And a constant voltage supply unit for modulating the magnitude of the voltage input from the power supply unit in consideration of the pulse signal and supplying it to the high frequency power generation unit. The method of claim 1, The power supply unit, An overvoltage blocking protection circuit which receives a commercial AC current and blocks the overvoltage current; And And a rectifier for rectifying the alternating current passing through the protection circuit and converting the alternating current into a direct current. The method of claim 1, The charging power control unit is a contactless charger, characterized in that for generating a control signal for modulating the width of the pulse current, the frequency of the pulse current, the amplitude of the pulse or the number of pulses. In a battery charge set comprising a contactless rechargeable battery and a contactless charger, The battery, A high frequency AC current inducing unit in which high frequency AC current is intermittently induced by a magnetic field generated by an external contactless charger intermittently, a rectifying unit receiving the induced high frequency AC current into a DC current, and a DC current from the rectifying unit. A constant voltage / constant current supply unit that receives input and supplies charging power to a battery cell in a constant voltage-constant current mode, and monitors the charging power supplied to the battery cell and monitors the charging result through an external wireless communication while the high frequency AC current is not induced. It includes; Monitoring unit for transmitting to the contactless charger of, The charger, The power supply unit receives a commercial AC current and converts it into a DC power supply, a charging power supply converting and supplying the power supplied from the power supply into power required for charging, and using the power supplied from the charging power supply unit. A high frequency power driver for intermittently applying a high frequency alternating current to a magnetic field generating unit, a magnetic field generating unit for receiving a high frequency alternating current from the high frequency power driving unit to form a magnetic field in an external space, and a high frequency alternating current is applied to the magnetic field generating unit While not, the charging power control unit for receiving the monitoring result through the wireless communication to control the charging power supply to adjust the power of the high frequency AC current applied to the magnetic field generating unit to adjust the charging power delivered to the battery side; Characterized by including Set of battery charge.  The method of claim 7, wherein The magnetic field generating unit is a coil to which a high frequency alternating current is applied to both ends, and the high frequency alternating current induction unit is a coil in which the magnetic flux of the magnetic field generated from the magnetic field generating unit crosses. The method of claim 7, wherein The monitoring unit, A wireless transmitter which wirelessly propagates the monitoring result through an antenna; First and second voltage detectors detecting voltages at the front and rear ends of the constant voltage / constant current supply unit, respectively; And And a microprocessor that checks the first and second voltages detected by the first and second voltage detectors, and outputs a monitoring result corresponding thereto to the wireless transmitter. The method of claim 9, The monitoring unit And a voltage comparator configured to compare the first and second voltages detected by the first and second voltage detectors and output a voltage comparison result. The method of claim 7, wherein The monitoring unit, A wireless transmitter which wirelessly propagates the monitoring result through an antenna; A current detector for measuring a current value supplied from the constant voltage / constant current supply unit to the battery cell; And And a microprocessor for outputting a monitoring result to the wireless transmitter in consideration of the current value detected by the current detector. The method of claim 7, wherein The magnetic field generated by the contactless charger is intermittently generated, The monitoring unit may further include a charge stop detection unit which receives a high frequency AC current output from the high frequency AC current inducing unit and detects a time point at which the induction of the high frequency AC current ends and outputs the same to the microprocessor. And the monitoring result is transmitted to an external contactless charger through wireless communication while induction of high frequency AC current is not performed after the time point is input. The method according to any one of claims 7 to 12, And the monitoring result is a charging power adjustment request signal. The method according to any one of claims 7 to 12, The monitoring result is a battery charge set, characterized in that the code indicating that the voltage difference, the voltage value between both ends of the constant voltage / constant current supply unit or the voltage between both ends. The method of claim 7, wherein The magnetic field generating unit is a battery charging set, characterized in that the coil to which a high frequency alternating current is applied to both ends. The method of claim 7, wherein The charging power control unit, A radio receiver which receives the monitoring result through an antenna; And And a microprocessor configured to adjust the power applied to the high frequency power generating unit by controlling the charging power supply unit by receiving the monitoring result from the wireless receiving unit. The method of claim 7, wherein The charging power supply unit A pulse signal generator for receiving a pulse driving signal from the microprocessor and outputting a pulse signal; And And a constant voltage supply unit for modulating the magnitude of the voltage input from the power supply unit in consideration of the pulse signal and supplying it to the high frequency power generation unit. The method of claim 7, wherein The power supply unit, An overvoltage blocking protection circuit which receives a commercial AC current and blocks the overvoltage current; And A rectifier for rectifying the AC current passing through the protection circuit and converting the current into a DC current; Battery charging set comprising a. The method of claim 7, wherein The charging power control unit is a battery charging set, characterized in that for generating a control signal for modulating the width of the pulse current, the frequency of the pulse current, the amplitude of the pulse or the number of pulses.

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