WO2021096327A1 - Wireless power receiver and control method for wireless power receiver - Google Patents

Abstract

According to various embodiments, a wireless power receiver for receiving wireless power from a wireless power transmitter, comprises: a resonant circuit configured to generate alternating-current power on the basis of a magnetic field generated by the wireless power transmitter; a power conversion circuit configured to convert the alternating-current power generated by the resonant circuit into direct-current power; and a control circuit, wherein the power conversion circuit comprises a first diode, a second diode, a third diode, a fourth diode, and a first switch, and the control circuit can be configured to adjust at least one of a voltage or a current of the direct-current power output from the power conversion circuit, by checking the at least one of the voltage or the current of the direct-current power output from the power conversion circuit and adjusting a phase of a first control signal to be applied to the first switch. Various other embodiments are possible.

Description

Wireless power receiver and control method of wireless power receiver

It relates to a wireless power receiver and a control method of the wireless power receiver.

Recently, wireless charging technology using an electromagnetic induction method or a magnetic resonance method has been spreading around electronic devices such as smart phones. When the wireless power transmitter and the wireless power receiver come into contact or approach within a certain distance, the battery of the wireless power receiver may be charged by electromagnetic induction or electromagnetic resonance between the transmitting coil of the wireless power transmitter and the receiving coil of the wireless power receiver.

1 shows a wireless transmission/reception system for performing wireless charging according to a comparative example. Referring to FIG. 1, the wireless power transmitter includes a bridge rectifier circuit 111, a power factor compensation circuit 112, _{an inverter 113 converting a link voltage V link} of the power factor compensation circuit 112 into an AC voltage, and an inverter. It may include a resonance circuit 114 configured to form a magnetic field based on the AC power output from (113). The inverter 113 may include a plurality of switches Q _S1 and Q _S2 , and each of the switches Q _S1 and Q _S2 is a metal oxide semiconductor field-effect transistor (hereinafter, referred to as a metal-oxide semiconductor field-effect transistor). -transistor, MOSFET)) and a diode connected in parallel with the MOSFET. The resonance circuit 114 may include at least one capacitor C _P and a transmission coil. The wireless power receiver may include a resonance circuit 121, a rectifier circuit 122, a converter 123, and a battery 124. The resonance circuit 121 of the wireless power receiver may include at least one capacitor C _s and at least one receiving coil, and generates AC power based on a magnetic field generated by the resonance circuit 114 of the wireless power transmitter. Can occur. The rectifier circuit 122 may include four diodes (D ₁ , D ₂ , D ₃ , D ₄ ) and a capacitor (C ₀ ), and the AC power generated in the resonance circuit 114 of the wireless power transmitter is DC power. Can be converted to The converter 123 may convert the DC power output from the rectifier circuit 122 into power having at least one of a voltage or current suitable for charging the battery 124 and output it to the battery 124. The converter 123 may include a plurality of switches S ₁ and S ₂ , at least one inductor L ₀ , and at least one capacitor C ₀ .

When the wireless power receiver includes a rectifier circuit and a converter, respectively, there is a limit to reducing the number of elements included in the wireless power receiver. In addition, when the wireless power receiver includes a rectifier circuit and a converter, respectively, there is a limit in reducing the volume of the wireless power receiver.

The wireless power receiver according to an embodiment includes one power conversion circuit that performs both functions of a rectifier circuit and a converter, and controls at least one of voltage or current of power output from the power conversion circuit by controlling the power conversion circuit. Can be adjusted.

According to an embodiment, a wireless power receiver for receiving wireless power from a wireless power transmitter includes a resonance circuit configured to generate AC power based on a magnetic field generated by the wireless power transmitter, and the AC generated in the resonance circuit. A power conversion circuit configured to convert power into DC power, and a control circuit, wherein the power conversion circuit includes a first switch, and the control circuit comprises a voltage of the DC power output from the power conversion circuit or It may be configured to check at least one of the currents and adjust at least one of the voltage or current of the DC power output from the power conversion circuit by adjusting the phase of the first control signal applied to the first switch.

According to an embodiment, a method performed in a wireless power receiver for receiving wireless power from a wireless power transmitter includes AC power based on a magnetic field generated by the wireless power transmitter through a resonance circuit included in the wireless power receiver. Generating, through a power conversion circuit included in the wireless power receiver and including a first switch, converting the AC power into DC power, and checking at least one of a voltage or a current of the DC power And adjusting at least one of a voltage or a current of the DC power output from the power conversion circuit by adjusting a phase of the first control signal applied to the first switch.

According to an embodiment, a wireless power receiver for receiving wireless power from a wireless power transmitter includes a resonance circuit configured to generate AC power based on a magnetic field generated by the wireless power transmitter, and the AC generated in the resonance circuit. A power conversion circuit configured to convert power into DC power, an auxiliary coil configured to generate a reference signal based on a magnetic field generated by the wireless power transmitter, and a control circuit, wherein the power conversion circuit includes at least one Including a first switch, the control circuit, based on the reference signal, to check the phase of the first control signal for controlling at least one second switch included in the wireless power transmitter, and the first control Applying a second control signal having a first phase difference with the signal to the at least one first switch, checking at least one of the voltage or current of the DC power output from the power conversion circuit, and output from the power conversion circuit In response to being confirmed that at least one of the voltage or current of the DC power is out of a predetermined voltage range and/or a predetermined current range, a second phase difference different from the first control signal and the first phase difference 3 may be configured to apply a control signal to the at least one first switch.

The wireless power receiver according to an embodiment includes a power conversion circuit, and may adjust at least one of a voltage or a current of power output from the power conversion circuit by adjusting a phase of a signal applied to a gate of a switch in the power conversion circuit. have. Accordingly, the wireless power receiver according to the exemplary embodiments may output an appropriate voltage or an appropriate current for charging the battery using a single power conversion circuit, instead of each having a rectifier circuit and a converter. Accordingly, the wireless power receiver according to the exemplary embodiments requires a smaller number of elements and can be produced in a small volume compared to the wireless power receiver each having a rectifier circuit and a converter.

1 illustrates a wireless transmission/reception system for performing wireless charging according to a comparative example.

2A is a diagram illustrating a wireless transmission/reception system performing wireless charging according to various embodiments.

2B is a block diagram of a wireless power receiver according to various embodiments.

2C is a flowchart illustrating an operation performed in a wireless power receiver according to various embodiments.

2D illustrates a power conversion circuit according to various embodiments.

3 illustrates an equivalent circuit of a wireless transmission/reception system performing wireless charging according to various embodiments.

4 illustrates various signals in a wireless transmission/reception system performing wireless charging according to various embodiments.

5A illustrates an equivalent circuit of a wireless transmission/reception system performing wireless charging according to various embodiments.

5B illustrates an equivalent circuit of a wireless transmission/reception system performing wireless charging according to various embodiments.

6 illustrates various signals in a wireless transmission/reception system performing wireless charging according to various embodiments.

7A illustrates an equivalent circuit of a wireless transmission/reception system performing wireless charging according to various embodiments.

7B is a diagram illustrating an equivalent circuit of a wireless transmission/reception system performing wireless charging according to various embodiments.

7C illustrates an equivalent circuit of a wireless transmission/reception system performing wireless charging according to various embodiments.

8A illustrates various signals in a wireless transmission/reception system performing wireless charging according to various embodiments.

8B illustrates various signals in a wireless transmission/reception system performing wireless charging according to various embodiments.

8C is a flowchart illustrating an operation performed by the wireless power receiver according to various embodiments.

9 illustrates a gain according to phase adjustment in a wireless power receiver according to various embodiments.

10A illustrates a wireless transmission/reception system performing wireless charging according to various embodiments.

10B is a diagram illustrating an equivalent circuit of a wireless transmission/reception system performing wireless charging according to various embodiments.

11A illustrates an equivalent circuit of a wireless transmission/reception system performing wireless charging according to various embodiments.

11B is a diagram illustrating a signal processing process performed by a wireless power receiver according to various embodiments.

11C illustrates various signals identified by the wireless power transmitter and the wireless power receiver according to various embodiments.

12 is a diagram illustrating an arrangement of a coil included in a wireless power transmitter and a wireless power receiver according to various embodiments.

2A is a diagram illustrating a wireless transmission/reception system performing wireless charging according to various embodiments. According to various embodiments, the wireless power transmitter includes a bridge rectifier circuit, a power factor compensation circuit 201, _{an inverter 202 converting a link voltage V link} of the power factor compensation circuit 201 into an AC voltage, and a resonance circuit 203. ) May be included. The power factor correction circuit 201 may include an inductor (L _B ), a diode (D _B ), a switch (Q _B ), and a capacitor (C _link ). The inverter 202 may include at least one switch (S ₁ , S ₂ ), and each of the at least one switch (S ₁ , S ₂ ) includes a MOSFET and a diode connected in parallel with the MOSFET. Can include. A portion of the resonance circuit 203 included in the wireless power transmitter may include a capacitor C _P and a transmission coil N _P. A portion of the resonance circuit 203 included in the wireless power transmitter may form a magnetic field based on AC power output from the inverter 202.

According to various embodiments, a wireless power receiver may include a portion of a resonant circuit 203 and a power conversion circuit 204. Although not shown in FIG. 2A, the wireless power receiver may further include a battery charged by power output from the power conversion circuit 204. A portion of the resonance circuit 203 included in the wireless power receiver may include at least one capacitor (C _s ) and a receiving coil (N _S ), and by a portion included in the wireless power transmitter of the resonance circuit 203 AC power can be generated based on the generated magnetic field. The power conversion circuit 204 may convert AC power generated by a portion of the resonance circuit 203 included in the wireless power receiver into DC power.

According to various embodiments, the power conversion circuit 204 includes four diodes (D ₁ , D ₂ , D ₃ , D ₄ ), a capacitor (C ₀ ), and at least one switch (S ₃ , S ₄ ). can do. 2A, _{the first terminal of the diode D 1 is} connected to the first terminal of the resonant circuit 203, and the second terminal of the diode D ₁ is connected to the first output terminal of the power conversion circuit 204. Is connected, the first terminal of the second diode (D ₂ ) is connected to the second terminal of the resonance circuit 203, and the second terminal of the second diode (D ₂ ) is the first output terminal of the power conversion circuit 204 Is connected to, the _{first end of the third diode D 3} is connected to the first end of the resonance circuit 203, and the second end of the third diode D ₃ is the first end of the switch S ₃ Is connected to, the first end of the fourth diode is connected to the second end of the resonant circuit 203, the second end of the fourth diode is connected to the first end of the switch S ₄ , and the switch S ₄ The second terminal of) may be connected to the second output terminal of the power conversion circuit 204, and the second terminal of the _{switch S 3 may be connected to the second output terminal of the power conversion circuit 204.}

While the wireless power receiver of FIG. 1 includes a rectifier circuit 122 and a converter 123 and the rectifier circuit 122 of FIG. 1 does not include a switch, the wireless power receiver of FIG. 2 has a rectifier circuit 122. And a power conversion circuit 204 instead of the converter 123, and the power conversion circuit 204 includes at least one switch S ₃ and S ₄ .

2B is a block diagram of a wireless power receiver according to various embodiments. Referring to FIG. 2B, the wireless power receiver 200b may include a resonance circuit 210b, a power conversion circuit 220b, a battery 230b, a control circuit 240b, and a communication circuit 250b.

The resonance circuit 210b of the wireless power receiver 200b may generate AC power based on a magnetic field generated by the resonance circuit of the wireless power transmitter. According to various embodiments, the resonance circuit 210b may have the same structure as a portion of the resonance circuit 203 included in the wireless power receiver as illustrated in FIG. 2A.

The power conversion circuit 220b may convert AC power generated by the resonance circuit 210b into DC power. According to various embodiments, the power conversion circuit 220b may convert AC power generated in the resonance circuit 210b into DC power having a current and voltage suitable for charging the battery 230b. According to various embodiments, the power conversion circuit 220b may have the same structure as the power conversion circuit 204 shown in FIG. 2A.

The control circuit 240b receives a signal from the power conversion circuit 220b and generates a control signal for controlling the power conversion circuit 220b based on the signal received from the power conversion circuit 220b to generate a power conversion circuit ( 220b) can be applied. According to various embodiments, the control circuit 240b may control other components of the wireless power receiver 200b and perform calculations based on signals received from other components of the wireless power receiver 200b. .

According to various embodiments, the control circuit 240b may check at least one of a voltage or a current of DC power output from the power conversion circuit 220b. According to various embodiments, the wireless power receiver 200b may include at least one of a voltage sensor or a current sensor, and the control circuit 240b is a power conversion circuit based on a signal from at least one of a voltage sensor or a current sensor. At least one of the voltage or current of the DC power output from 220b may be checked. According to various embodiments, the control circuit 240b may check _{the output voltage V 0} of the power conversion circuit 220b illustrated in FIG. 2A. According to various embodiments, the control circuit 240b may check the current flowing from the power conversion circuit 220b to the battery 230b.

According to various embodiments, the control circuit 240b may check a phase of a control signal applied to a gate of a MOSFET _{included in at least one switch S 1} and S _{2 included in the wireless power transmitter.} According to various embodiments, the control circuit 240b includes a MOSFET included in _{at least one switch S 1} , S ₂ based on at least one signal received from the wireless power transmitter through the communication circuit 250b. You can check the phase of the control signal applied to the gate of ). According to various embodiments, the power conversion circuit 220b further includes an auxiliary coil configured to generate a reference signal based on a magnetic field generated by the wireless power transmitter, and the control circuit 240b includes a reference signal generated from the auxiliary coil. By checking, it is possible to check the phase of the control signal applied to the gate of the MOSFET included in at least one switch (S ₁ , S _{2) included in the wireless power transmitter.}

According to various embodiments, the control circuit 240b provides a control signal having a phase difference with a control signal applied to a gate of a MOSFET _{included in at least one switch S 1} and S _{2 included in the wireless power transmitter.} It may be applied to the gate of a MOSFET _{included in at least one switch (eg, S 3} and S ₄ of FIG. 2A) included in the power conversion circuit 220b.

According to various embodiments, the control circuit 240b includes a control signal of a MOSFET _{included in at least one switch (eg, S 3} , S _{4 in FIG. 2A) included in the power conversion circuit 220b.} While being applied to the gate, at least one of the voltage or current of DC power output from the power conversion circuit 220b is checked, and at least one of the checked voltage or current is out of a predetermined voltage range and/or a predetermined current range. In case, the phase of the control signal is changed, and the phase-changed control signal is a MOSFET _{included in at least one switch (eg, S 3} , S _{4 in FIG. 2A) included in the power conversion circuit 220b.} Can be applied to the gate of According to various embodiments, the control circuit 240b is the control signal until at least one of the voltage or current of the DC power output from the power conversion circuit 220b falls within a predetermined voltage range and/or a predetermined current range. By changing the phase, at least one of the voltage or current of DC power output from the power conversion circuit 220b may be checked. According to various embodiments, the voltage output from the power conversion circuit 220b may _{mean an output voltage (V o} ) of the power conversion circuit 204 shown in FIG. 2A. According to various embodiments, the current output from the power conversion circuit 220b may _{mean an output current i o} of the power conversion circuit in the wireless power receiver 320b illustrated in FIG. 3.

The communication circuit 250b may communicate with other electronic devices other than the wireless power receiver 200b. According to various embodiments, the communication circuit 250b may perform wireless communication with a wireless power transmitter that supplies wireless power to the wireless power receiver 200b. For example, the communication circuit 250b may perform Bluetooth low energy (BLE) communication with the wireless power transmitter.

2C is a flowchart illustrating an operation performed in a wireless power receiver according to various embodiments. 2C, a control circuit (e.g., control circuit 240b) of a wireless power receiver (e.g., wireless power receiver 200b) is a power conversion circuit (e.g., power conversion) in operation 210c. At least one of a voltage or a current of DC power output from the circuit 220b may be checked. According to various embodiments, the voltage output from the power conversion circuit 220b may _{mean an output voltage (V o} ) of the power conversion circuit 204 shown in FIG. 2A. According to various embodiments, the current output from the power conversion circuit 220b may _{mean an output current i o} of the power conversion circuit in the wireless power receiver 320b illustrated in FIG. 3.

According to various embodiments, the wireless power receiver 200b may include at least one of a voltage sensor or a current sensor, and the control circuit 240b is a power conversion circuit based on a signal from at least one of a voltage sensor or a current sensor. At least one of the voltage or current of the DC power output from 220b may be checked.

In operation 220c, a control circuit (e.g., control circuit 240b) of a wireless power receiver (e.g., wireless power receiver 200b) is connected to a power conversion circuit (e.g., power conversion circuit 204). At least one of the voltage or current of DC power output from the power conversion circuit 204 may be adjusted by adjusting the phase of the first control signal applied to the included at least one switch S ₃ and S _4. According to various embodiments, at least one switch (S ₃ , S ₄ ) may include a MOSFET and a diode connected in parallel with the MOSFET, and the first control signal is included _{in the switch S 3.} A control signal applied to a gate of a MOSFET and a control signal applied to a gate of a MOSFET included in the _{switch S 3 may be included.}

_{The phase of the first control signal applied to at least one switch (S 3} , S ₄ ) included in the power conversion circuit (eg, the power conversion circuit 204) and the DC power output from the power conversion circuit 204 The relationship between at least one of the voltage or current of will be described later with reference to FIGS. 4 to 8B.

2D illustrates a power conversion circuit according to various embodiments. Although in FIG. 2A the power conversion circuit 204 is shown to include four diodes D ₁ , D ₂ , D ₃ , D ₄ , according to various embodiments, as shown in FIG. 2D, power conversion The circuit 204 may include four _{switches SR 1} , SR ₂ , SR ₃ , and SR ₄ instead of four _{diodes D 1} , D ₂ , D ₃ and D ₄ . According to various embodiments, each of the four switches SR ₁ , SR ₂ , SR ₃ , and SR ₄ may include a MOSFET and a diode connected in parallel with the MOSFET. Hereinafter, in the present specification, a _{description will be made mainly on a power conversion circuit including four diodes (D 1} , D ₂ , D ₃ , D ₄ ), but according to various embodiments, FIGS. 3, 10A, 10B, and 11 In the illustrated wireless power receiver, four diodes D ₁ , D ₂ , D ₃ and D ₄ may be replaced with four switches SR ₁ , SR ₂ , SR ₃ and SR _4.

3 illustrates an equivalent circuit of a wireless transmission/reception system performing wireless charging according to various embodiments. Specifically, FIG. 3 shows an equivalent circuit of the wireless power transmitter and wireless power receiver shown in FIG. 2A. Referring to FIG. 3, the wireless power transmitter 310 may include an input power V _in , a plurality of switches S ₁ and S ₂ , a capacitor C _P , and a transmission coil L _P. The inductor L _lkp and the inductor L _M represent the non-ideal characteristics of the transmitting coil L _{P as equivalent inductance.} The bridge rectification circuit and the power factor correction circuit 201 shown in FIG. 2A are simply expressed as _{input power (V in ).}

The wireless power receiver 320 includes a receiving coil (L _S ), a capacitor (C _S ), four diodes (D ₁ , D ₂ , D ₃ , D ₄ ), a capacitor (C _o ), and a plurality of switches (S _{3 ).} , S ₄ ), and a load (R _o ). The receiving coil L _S and the capacitor C _S may form a resonant circuit and generate wireless power based on a magnetic field generated by _{the transmitting coil L P} of the wireless power transmitter 310.

4 illustrates various signals in a wireless transmission/reception system performing wireless charging according to various embodiments. _{Specifically, FIG. 4 is a control signal applied to a plurality of switches (S 3} , S ₄ ) of the wireless power receiver 320 shown in FIG. 3 is _{a plurality of switches (S 1} , S ₂ ) of the wireless power transmitter 310. ), and the waveforms of voltage and/or current in the wireless power transmitter and wireless power receiver, and various control signals in a wireless transmission/reception system performing wireless charging when synchronized with a control signal applied to ). _{In other words, FIG. 4 is a control signal applied to a plurality of switches S 3} and S ₄ of the wireless power receiver 320 illustrated in FIG. 3 and a plurality of switches S ₁ and S _{2 of the wireless power transmitter 310.} ) Shows waveforms of various control signals and voltages and/or currents in the wireless power transmitter and wireless power receiver when the phase difference between the control signals applied to) is zero.

In FIG. 4, the first control signal 410 may be a control signal applied to _{a plurality of switches S 1} and S _{2 of the wireless power transmitter 310.} The first control signal 410 may control the _{switch S 1} to be turned on and the switch S ₂ to be turned off in a period _{from t 0} to t _2. Although not shown in FIG. 4, the first control signal 410 controls the switch S ₁ to be turned off and the switch S ₂ to be turned on in the section immediately before _{t 0 and immediately after t 2.} can do.

In FIG. 4, the second control signal 420 may be a control signal applied to _{a plurality of switches S 3} and S _{4 of the wireless power receiver 320.} The second control signal 420 may control the switch S ₄ to an on state and control the switch S ₃ to an off state in a _{period from t 0} to t _2. Although not shown in Figure 4, the second control signal 420 controls the switch (S ₄ ) to the off state and the switch (S ₃ ) to the on state in the section immediately before _{t 0 and immediately after t 2} can do.

V _p shows a waveform of a voltage applied to the transmitting side including the _{inductor L lkp} , the inductor L _M , and the transmitting coil L _P. i _p shows the waveform of the current flowing through the inductor L _{lkp shown in FIG. 3.} i _s shows the waveform of the current flowing through the receiving coil L _{S shown in FIG. 3.}

5A illustrates an equivalent circuit of a wireless transmission/reception system performing wireless charging according to various embodiments. Specifically, FIG. 5A shows an equivalent circuit of the wireless power transmitter 310 and the wireless power receiver 320 shown in FIG. 3 in a section _{from t 0} to t _{1 in FIG. 4.}

_{In the section from t 0} to t ₁ in FIG. 4, since the first control signal 410 controls the switch S ₁ in the ON state and controls the switch S ₂ in the OFF state, the switch S ₂ Since no current flows in the wireless power transmitter 310, the switch S ₂ may not be displayed in the equivalent circuit 510a of the wireless power transmitter 310. _{In the section from t 0} to t ₁ in FIG. 4, since the second control signal 420 controls the switch S ₄ to the on state and controls the switch S ₃ to the off state, the switch S ₃ And since current does not flow through the diode D _{3 , the switch S 3} , the diode D ₁ , and the diode D ₃ may not be displayed in the equivalent circuit 520a of the wireless power receiver 320. Further, the diode (D _2), because the current in the diode (D ₂₎ flow, an equivalent circuit (520a) of the wireless power receiver 320 may not be displayed.

Referring back to FIG. 4, in the period _{from t 0} to t _{1 , the voltage (V p} ) applied to the transmitting side including the inductor (L _lkp ), the inductor (L _M ), and the transmitting coil (L _P ) is mathematically It can be expressed as Equation 1.

In Equation 1, N _eff has a relationship between the inductance of the _{transmission coil L P} of the wireless power transmitter 310 and the inductance of the reception coil L _{S of the wireless power receiver 320 and Equation 2.}

In Equation 1, V _o is an output voltage of the power conversion circuit of _{the wireless power receiver 320, and V CS} may be a voltage applied _{to the capacitor C S} included in the resonance circuit of the wireless power receiver 320.

Referring to FIG. 3, in the period _{from t 0} to t ₁ , a voltage as much as _{V in} -V _CP is applied to the transmitting side including the inductor (L _lkp ), the inductor (L _M ), and the transmitting coil (L _{P ).} I can. Here, V _CP may be a voltage applied _{to the capacitor C P} included in the resonance circuit of the wireless power transmitter 310.

In the period from t ₀ to t ₁ , the switch (S ₄ ) is on and V _in -V _{CP is greater than the voltage (V p} ) according to Equation 1, so the inductor (L _lkp ) shown in FIG. The flowing current i _p may increase due to resonance of the inductor L _lkp and the capacitor C _P.

In the period from t ₀ to t ₁ , the current (i _s ) flowing through the receiving coil (L _S ) is the current flowing through the inductor (L _M ) (i _LM ) from the current flowing through the illustrated inductor (L _{lkp ) (i p ).} It can be proportional to the amount of change in current minus ). Accordingly, the current i _s flowing through the receiving coil L _S may have a sine wave shape.

5B illustrates an equivalent circuit of a wireless transmission/reception system performing wireless charging according to various embodiments. Specifically, FIG. 5B shows an equivalent circuit of the wireless power transmitter 310 and the wireless power receiver 320 shown in FIG. 3 in a section _{from t 1} to t _{2 in FIG. 4.}

_{In t 1} of FIG. 4, the current (i _p ) flowing through the inductor (L _lkp ) and the current (i _LM ) flowing through the inductor (L _M ) may be the same, and at this time, the wireless power transmitter 310 and the wireless power receiver 320 may be magnetically separated, and the diode D ₁ may be switched to an off state. Therefore, in the interval from t ₁ to t _2, the other components other than the equivalent circuit (520a) of the wireless power receiver 320, capacitors (C _O) and a load (R _O) can not be displayed. In addition, in _{the section from t 1} to t ₂ , the first control signal 410 controls the position (S ₁ ) to be on and the switch (S ₂ ) to be turned off, so that the switch (S ₂ ) is _{Since current does not flow, the switch S 2} may not be displayed in the equivalent circuit 510a of the wireless power transmitter 310.

In the period from t ₁ to t ₂ , since the wireless power transmitter 310 and the wireless power receiver 320 are magnetically separated, the inductor (L _lkp ), the inductor (L _M ), and the transmitting coil (L _P ) are The voltage of the receiving side viewed from the including transmitting side may be zero. In addition, a voltage as much as _{V in} -V _CP may be applied to the transmission side including the _{inductor L lkp} , the inductor L _M , and the transmission coil L _P.

In the interval from t ₁ to t _2, the inductor (i _p) current flowing through the (L _lkp) an inductor (L _lkp), an inductor (L _M), and a linear period of slow resonance by the resonance between the capacitor (C _P) It can increase as an enemy. In the period from t ₁ to t ₂ , since the wireless power transmitter 310 and the wireless power receiver 320 are magnetically separated, the current i _{s flowing through the receiving coil L S} may be zero.

6 illustrates various signals in a wireless transmission/reception system performing wireless charging according to various embodiments. _{4 is a control signal applied to a plurality of switches (S 3} , S ₄ ) of the wireless power receiver 320 shown in FIG. 3 is applied to a plurality of switches (S ₁ , S ₂ ) of the wireless power transmitter 310 Various control signals and wireless power transmitters and wireless power when there is a non-zero phase difference from the control signals applied to _{the plurality of switches (S 1} , S ₂ ) of the wireless power transmitter 310 without being synchronized with the control signal being Shows the waveforms of voltage and/or current in the receiver.

In FIG. 6, the first control signal 610 may be a control signal applied to _{a plurality of switches S 1} and S _{2 of the wireless power transmitter 310.} The first control signal 610 may control the _{switch S 1} to be turned on and the switch S ₂ to be turned off in a period _{from t 0} ′ to t _{3 ′.} Although not shown in FIG. 6, the first control signal 610 is t ₀ ' In the section immediately before and _{immediately after t 3} ′, the switch S ₁ may be controlled in an off state, and the switch S ₂ may be controlled in an on state.

In FIG. 6, the second control signal 620 may be a control signal applied to _{a plurality of switches S 3} and S _{4 of the wireless power receiver 320.} The second control signal 620 may control the switch S ₄ to an off state and control the switch S ₃ to an on state in a _{period from t 0} ′ to t _{1 ′.} 6, the second control signal 620 is t ₀ ' Even in the previous section, the switch S ₄ can be controlled in an off state, and the switch S ₃ can be controlled in an on state. The second control signal 620 may control the switch S ₄ to an on state and control the switch S ₃ to an off state in a _{period from t 1} ′ to t _{3 ′.} As shown in FIG. 6, the second control signal 620 may control the _{switch S 4} to be turned on and the switch S ₃ to be turned off even in a period after _{t 3 ′.}

Like FIG. 4, V _p shows a waveform of a voltage applied to the transmission side including the _{inductor L lkp} , the inductor L _M , and the transmission coil L _P. i _p shows the waveform of the current flowing through the inductor L _{lkp shown in FIG. 3.} i _s shows the waveform of the current flowing through the receiving coil L _{S shown in FIG. 3.}

7A illustrates an equivalent circuit of a wireless transmission/reception system performing wireless charging according to various embodiments. Specifically, FIG. 7A shows an equivalent circuit of the wireless power transmitter 310 and the wireless power receiver 320 shown in FIG. 3 in a section _{from t 0} ′ to t _{1 ′ in FIG. 6.}

_{In the section from t 0} ′ to t ₁ ′ in FIG. 6, since the first control signal 610 controls the switch S ₂ to be turned off _{, current does not flow through the switch S 2} , so that the wireless power transmitter ( In the equivalent circuit 710a of 310), the switch S ₂ may not be displayed.

_{In the section from t 0} ′ to t ₁ ′ in FIG. 6, the second control signal 620 controls the switch (S ₄ ) to be turned off, and the diode (D ₃ ) does not flow current to the switch (S _{3 ). Therefore, components other than the capacitor C O} and the load R _O may not be displayed in the equivalent circuit 720a of the wireless power receiver 320. In the period from t ₀ ′ to t ₁ ′, the wireless power transmitter 310 and the wireless power receiver 320 may be magnetically separated.

In _{the section from t 0} ′ to t ₁ ′, since the wireless power transmitter 310 and the wireless power receiver 320 are magnetically separated, the inductor L _lkp , the inductor L _M , and the transmission coil L _P The voltage of the receiving side viewed from the transmitting side including) may be zero. In addition, _{the voltage V p} applied to the transmission side including the _{inductor L lkp} , the inductor L _M , and the transmission coil L _P may be V _in -V _CP.

'from t _1' t ₀ in the interval up to the inductor (i _p) current flowing through the (L _lkp) is slow resonance by a resonance between the inductor (L _lkp), an inductor (L _M), and a capacitor (C _P) It can increase linearly in cycles. In addition, in _{the section from t 0} ′ to t ₁ ′, since the wireless power transmitter 310 and the wireless power receiver 320 are magnetically separated, the current i _{s flowing through the receiving coil L S} is 0 days. I can.

7B is a diagram illustrating an equivalent circuit of a wireless transmission/reception system performing wireless charging according to various embodiments. Specifically, FIG. 7B shows an equivalent circuit of the wireless power transmitter 310 and the wireless power receiver 320 shown in FIG. 3 in a section _{from t 1} ′ to t _{2 ′ in FIG. 6.}

_{In the section from t 1} ′ to t ₂ ′ in FIG. 6, since the first control signal 610 controls the switch S ₂ to be turned off, the current does not flow through the _{switch S 2, so that the wireless power transmitter (} In the equivalent circuit 710b of 310), the switch S ₂ may not be displayed. _{In the section from t 1} ′ to t ₂ ′ in FIG. 6, since the second control signal 620 controls the switch S ₃ in the off state and controls the switch S ₄ in the on state, the wireless power receiver In the equivalent circuit 720b of 320, the switch S ₃ and the diode D ₂ may not be displayed.

Referring to FIG. 6, in the period _{from t 1} ′ to t _{2 ′, the voltage (V p} ) applied to the transmitting side including the inductor (L _lkp ), the inductor (L _M ), and the transmitting coil (L _P ) is It can be expressed as in Equation 1. Details of Equations 1 and 2 are as described above.

Referring to FIG. 6, in a section _{from t 1} ′ to t ₂ ′, a voltage equal to _{V in} -V _CP is provided at the transmitting side including the _{inductor L lkp} , the inductor L _M , and the transmitting coil L _P. You can take this. Here, V _CP may be a voltage applied _{to the capacitor C P} included in the resonance circuit of the wireless power transmitter 310. Since the switch S ₄ is on and V _in -V _{CP is greater than the voltage V p} according to Equation 1, the current i _p flowing through the inductor L _lkp shown in FIG. 3 is the inductor L _lkp ) and the capacitor C _P may increase due to resonance.

In _{the section from t 1} ′ to t _{2 ′, the current (i s} ) flowing through the receiving coil (L _S ) is from the current flowing through the illustrated inductor (L _lkp ) (i _p ) to the current flowing through the inductor (L _{M) (} It can be proportional to the amount of change in current minus i _{LM ).} Accordingly, the current i _s flowing through the receiving coil L _S may have a sine wave shape.

7C illustrates an equivalent circuit of a wireless transmission/reception system performing wireless charging according to various embodiments. Specifically, FIG. 7C shows an equivalent circuit of the wireless power transmitter 310 and the wireless power receiver 320 shown in FIG. 3 in a section _{from t 2} ′ to t _{3 ′ in FIG. 6.}

_{In t 2} ′ of FIG. 6, the current (i _p ) flowing through the inductor (L _lkp ) and the current (i _LM ) flowing through the inductor (L _M ) may be the same, and at this time, the wireless power transmitter 310 and the wireless power The receiver 320 may be magnetically separated, and the diode D ₁ may be switched to an off state. Accordingly, in the period from t ₂ ′ to t ₃ ′, other components other than the _{capacitor C O} and the load R _O may not be displayed in the equivalent circuit 730a of the wireless power receiver 320. In addition, in _{the section from t 2} ′ to t ₃ ′, the first control signal 610 controls the position (S ₁ ) to be turned on and the switch (S ₂ ) to be turned off, so that the switch (S _{2) ), the switch S 2} may not be displayed in the equivalent circuit 710a of the wireless power transmitter 310.

In _{the section from t 2} ′ to t ₃ ′, since the wireless power transmitter 310 and the wireless power receiver 320 are magnetically separated, the inductor L _lkp , the inductor L _M , and the transmission coil L _P The voltage of the receiving side viewed from the transmitting side including) may be zero. In addition, a voltage as much as _{V in} -V _CP may be applied to the transmission side including the _{inductor L lkp} , the inductor L _M , and the transmission coil L _P.

'from t _3, t ₂ in the range of up to an inductor (i _p) current flowing through the (L _lkp) is slow resonance by a resonance between the inductor (L _lkp), an inductor (L _M), and a capacitor (C _P) It can increase linearly in cycles. In the period from t ₁ to t ₂ , since the wireless power transmitter 310 and the wireless power receiver 320 are magnetically separated, the current i _{s flowing through the receiving coil L S} may be zero.

8A illustrates various signals in a wireless transmission/reception system performing wireless charging according to various embodiments. _{Specifically, FIG. 8A shows that the control signals applied to the plurality of switches S 3} and S ₄ of the wireless power receiver 320 shown in FIG. 3 are applied to the plurality of switches S ₁ and S _{2 of the wireless power transmitter 310.} ), and the waveforms of voltage and/or current in the wireless power transmitter and wireless power receiver, and various control signals in a wireless transmission/reception system performing wireless charging when synchronized with a control signal applied to ). _{In other words, FIG. 8A illustrates a control signal applied to a plurality of switches S 3} and S ₄ of the wireless power receiver 320 illustrated in FIG. 3 and a plurality of switches S ₁ and S _{2 of the wireless power transmitter 310.} ) Shows waveforms of various control signals and voltages and/or currents in the wireless power transmitter and wireless power receiver when the phase difference between the control signals applied to) is zero.

In FIG. 8A, the definitions described above with reference to FIG. 4 may be applied equally to the definitions of the first control signal 810a, the second control signal 820a, i _p 830a, and i _{s 840a.} have. It _{can be seen that the waveforms of i p} (830a) and i _s (840a) are the same as the waveforms shown in FIG. 4.

8B illustrates various signals in a wireless transmission/reception system performing wireless charging according to various embodiments. _{8B is a control signal applied to a plurality of switches (S 3} , S ₄ ) of the wireless power receiver 320 shown in FIG. 3 is applied to a plurality of switches (S ₁ , S ₂ ) of the wireless power transmitter 310 Various control signals and wireless power transmitters and wireless power when they are not synchronized with the control signals and have various phase differences compared to the control signals applied to the plurality of switches (S ₁ , S _{2) of the wireless power transmitter 310} Shows the waveforms of voltage and/or current in the receiver.

In FIG. 8A, a first control signal 810b, a second control signal 821b, 822b, 823b, 824b, i _p (831b, 832b, 833b, 834b), and i _s (841b, 842b, 843b, 844b) With respect to the definition of, the definition described above with reference to FIG. 4 may be equally applied. The second control signal 821b is the same control signal as the second control signal 820a of FIG. 8A, that is, a control signal having a phase difference of 0 with the first control signal 810b. The second control signal 822b is a control signal delayed by a first phase difference compared to the first control signal 810b. The third control signal 823b is a control signal delayed by a second phase difference greater than the first phase difference compared to the first control signal 810b. The fourth control signal 824b is a control signal delayed by a third phase difference greater than the second phase difference compared to the first control signal 810b.

i _p 831b represents a current flowing through the _{inductor L lkp} when the second control signal 821b is applied to _{the plurality of switches S 3} and S ₄ of the wireless power receiver 320. i _p (832b), i _p (833b), and i _p (834b) are respectively the second control signal 822b, the second control signal 823b, and the second control signal 823b is the wireless power receiver 320 _{) Represents} the current flowing through the inductor L lkp when applied to the plurality of switches S ₃ and S _4.

i _s 841b represents a current flowing through the receiving coil L _{S when the second control signal 821b is applied to the plurality of switches S 3} and S ₄ of the wireless power receiver 320. i _s (842b), i _s (843b), and i _s (844b) are respectively the second control signal 822b, the second control signal 823b, and the second control signal 823b is the wireless power receiver 320 ) Represents the current flowing through the receiving coil L _S when applied to the plurality of switches S ₃ and S _4.

A _{i p (831b, 832b, 833b} , 834b) a, a _{i p (831b, 832b, 833b} , 834b) slows applied to the second control signal the phase difference is larger than the first control signal (810b) Referring shown in Figure 8b It can be seen that the starting point of the sine wave component of is delayed, and _{the maximum value of i p} (831b, 832b, 833b, 834b) also decreases. Also, referring to the _{i s (841b, 842b, 843b} , 844b) shown in Figure 8b, the first control signal (810b) the second control signal the phase difference is greater is the more i _s (841b as compared to, 842b, 843b, It can be seen that the time point at which 844b) starts to increase in the form of a sine wave is delayed, and _{the maximum value of i s} (841b, 842b, 843b, 844b) also decreases. That is, as the phase difference of the second control signal is greater than that of the first control signal 810b, the voltage and/or current of the power output from the power conversion circuit 204 may be smaller.

8C is a flowchart illustrating an operation performed by the wireless power receiver according to various embodiments. Referring to FIG. 8C, in operation 810c, a control circuit (eg, control circuit 240b) of a wireless power receiver (eg, wireless power receiver 200b) is at least one unit included in the wireless power transmitter. 1 It is possible to check the phase of the first control signal for controlling the switch (eg, switches S ₁ and S _{2 ).} According to various embodiments, the first control signal may be a signal applied to a gate of a MOSFET included in at least one first switch (eg, switches S ₁ and S _{2 ).}

According to various embodiments, the control circuit 240b performs wireless communication with the wireless power transmitter through a communication circuit (for example, the communication circuit 250b), and at least one received through wireless communication from the wireless power transmitter. Based on the signal, it is possible to check the phase of the first control signal for controlling at least one first switch (eg, switches S ₁ and S _{2) included in the wireless power transmitter.}

According to various embodiments, the control circuit 240b transmits a reference signal through an auxiliary coil configured to generate a reference signal based on a magnetic field generated by the wireless power transmitter, as will be described later with reference to FIGS. 11A to 11C. The phase of the first control signal for controlling _{at least one first switch (eg, switches S 1} and S ₂ ) included in the wireless power transmitter may be determined based on the reference signal.

In operation 830c, the control circuit 240b may check at least one of a voltage or a current of DC power output from the power conversion circuit. According to various embodiments, the voltage output from the power conversion circuit 220b may _{mean an output voltage (V o} ) of the power conversion circuit 204 shown in FIG. 2A. According to various embodiments, the current output from the power conversion circuit 220b may _{mean an output current i o} of the power conversion circuit in the wireless power receiver 320b illustrated in FIG. 3.

Details of operation 210c of FIG. 2C may be equally applied to operation 830c.

In operation 840c, the control circuit 240b may check whether at least one of the voltage or current of the DC power output from the power conversion circuit, determined in operation 830c, is within a predetermined voltage range and/or a predetermined current range. . According to various embodiments, the predetermined voltage range and/or the predetermined current range may be a voltage range and/or a current range suitable for charging the battery of the wireless power receiver 200b.

When it is determined that at least one of the voltage or current of the DC power output from the power conversion circuit is not within the predetermined voltage range and/or the predetermined current range, the control circuit 240b is in operation 850c, and the wireless power receiver 200b The phase of the second control signal for controlling at least one second switch (eg, switches S ₃ and S _{4) included in may be changed.} According to various embodiments, the second control signal may be a signal applied to a gate of a MOSFET included in at least one second switch (eg, switches S ₃ and S _{4 ).}

After performing operation 850c, the control circuit 240b performs operations 830c and 840c again, and in operation 840c, at least one of the voltage or current of DC power output from the power conversion circuit is determined in a predetermined voltage range and/or in advance. The phase of the second control signal can be changed until it is confirmed that it is within the determined current range.

When it is determined that at least one of the voltage or current of the DC power output from the power conversion circuit is within a predetermined voltage range and/or a predetermined current range, the control circuit 240b adjusts the phase of the second control signal in operation 860c. While maintaining, the second control signal may be applied to at least one second switch (eg, switches S ₃ and S _{4) included in the power conversion circuit.}

9 illustrates a change in gain according to phase adjustment in a wireless power receiver according to various embodiments. The horizontal axis of FIG. 9 is a normalized frequency, and indicates a value obtained by dividing the operating frequency by the resonance frequency of the resonance circuit. _{Curve 910 is a control signal applied to a plurality of switches (S 3} , S ₄ ) of the wireless power receiver 320, a control applied to a plurality of switches (S ₁ , S ₂ ) of the wireless power transmitter 310 When the phase difference for the signal is 0π, it represents the relationship of the gain to the normalized frequency. Curve 920, curve 930, curve 940, curve 950, and curve 960 are control signals applied to _{a plurality of switches S 3} and S _{4 of the wireless power receiver 320, respectively} Of, when the phase difference for the control signal applied to the plurality of switches (S ₁ , S ₂ ) of the wireless power transmitter 310 is 0.1π, 0.2π, 0.3π, 0.4π, and 0.5π, the normalized frequency Represents the relationship of gains to.

Referring to FIG. 9, a plurality of switches of the wireless power transmitter 310 of control signals applied to _{a plurality of switches S 3} and S ₄ of the wireless power receiver 320 in a section in which the normalized frequency is greater than or equal to a specific value. It can be seen that the larger the phase difference for the control signal applied to (S ₁ , S _{2 ), the smaller the gain.} This is consistent with the results shown in FIG. 8B.

A straight line 901 represents an exemplary operating frequency capable of obtaining a gain within the range required by the wireless power receiver by adjusting the phase difference in an exemplary situation where the range of the gain required by the wireless power receiver is 1.5 to 2.

10A illustrates a wireless transmission/reception system performing wireless charging according to various embodiments. According to various embodiments, the wireless power transmitter includes a bridge rectifier circuit, a power factor compensation circuit 1001a, _{an inverter 1002a converting the link voltage V link} of the power factor compensation circuit 1001a into an AC voltage, and a resonance circuit 1003a. ) May be included. According to various embodiments, the wireless power receiver may include a part of the resonance circuit 1003a and the power conversion circuit 1004a.

Compared with FIG. 2A, the configuration of the wireless power transmitter in the wireless transmission/reception system of FIG. 10A is the same as that of FIG. 2A, and the configuration of the power conversion circuit 1004a is part of the power conversion circuit 204 of FIG. 2A. In contrast, the configuration of the resonant circuit 1003a is the same as the configuration of the resonant circuit 203 of Fig. 2A. In more detail, the power conversion circuit 204 of FIG. 2A includes four diodes (D ₁ , D ₂ , D ₃ , D ₄ ), a capacitor (C ₀ ), and two switches (S ₃ , S ₄ ). On the other hand, the power conversion circuit 1004a of FIG. 10A may include four diodes D ₁ , D ₂ , D ₃ and D ₄ , a capacitor C ₀ , and one switch S ₃ .

Referring to FIG. 10A, _{the first terminal of the diode D 1 is} connected to the first terminal of the resonant circuit 203, and the second terminal of the diode D ₁ is connected to the first output terminal of the power conversion circuit 204. Is connected, the first terminal of the second diode (D ₂ ) is connected to the second terminal of the resonance circuit 203, and the second terminal of the second diode (D ₂ ) is the first output terminal of the power conversion circuit 204 Is connected to, the _{first end of the third diode D 3} is connected to the first end of the resonance circuit 203, and the second end of the third diode D ₃ is the first end of the switch S ₃ Is connected to, the first end of the fourth diode is connected to the second end of the resonant circuit 203, the second end of the fourth diode is connected to the second output end of the power conversion circuit 204, and the switch S _{The second terminal of 3} ) may be connected to the second output terminal of the power conversion circuit 204.

The power conversion circuit 1004a of FIG. 10A is shown to include four diodes D ₁ , D ₂ , D ₃ , and D ₄ , but as described above with reference to FIG. 2D, according to various embodiments, power The conversion circuit may include four _{switches SR 1} , SR ₂ , SR ₃ , and SR ₄ instead of four _{diodes D 1} , D ₂ , D ₃ , and D ₄ .

10B is a diagram illustrating an equivalent circuit of a wireless transmission/reception system performing wireless charging according to various embodiments. Specifically, FIG. 10B shows an equivalent circuit of the wireless power transmitter and wireless power receiver shown in FIG. 10A. Referring to FIG. 10B, the wireless power transmitter 1010b may include an input power V _in , a plurality of switches S ₁ and S ₂ , a capacitor C _P , and a transmission coil L _P. The inductor L _lkp and the inductor L _M represent the non-ideal characteristics of the transmitting coil L _{P as equivalent inductance.} The bridge rectification circuit and the power factor correction circuit 201 shown in FIG. 10A are simply expressed as _{input power (V in ).}

The wireless power receiver 1020b includes a receiving coil (L _S ), a capacitor (C _S ), four diodes (D ₁ , D ₂ , D ₃ , D ₄ ), a capacitor (C _o ), a switch (S ₃ ), and It may include a load (R _{o ).} The receiving coil L _S and the capacitor C _S may form a resonant circuit and generate wireless power based on a magnetic field generated by _{the transmitting coil L P} of the wireless power transmitter 310.

According to various embodiments, the operations described above with reference to FIG. 8C may also be performed in the wireless power receiver illustrated in FIGS. 10A and 10B. 2 In this case, the second control signal may be applied to the switch (S _3), the operation for applying a second control signal to at least one of second switches in 820c operation and 860c operation switch (S ₃₎ It can be replaced by an operation of applying a control signal.

11A illustrates an equivalent circuit of a wireless transmission/reception system performing wireless charging according to various embodiments. Referring to FIG. 11A, the wireless power transmitter 1110 may include an input power V _in , a plurality of switches S ₁ and S ₂ , a capacitor C _P , and a transmission coil L _P. The inductor L _lkp and the inductor L _M represent the non-ideal characteristics of the transmitting coil L _{P as equivalent inductance.}

According to various embodiments, the wireless power receiver 1120 includes a receiving coil (L _S ), an auxiliary coil (L _A ), a capacitor (C _S ), four diodes (D ₁ , D ₂ , D ₃ , D ₄ ), It may include a capacitor (C _o ), a switch (S ₃ ), and a load (R _o ). The receiving coil L _S and the capacitor C _S may form a resonant circuit and generate wireless power based on a magnetic field generated by _{the transmitting coil L P} of the wireless power transmitter 310. The auxiliary coil L _{A may generate a reference signal based on a magnetic field generated by the transmission coil L P} of the wireless power transmitter 310 and transmit it to the control circuit (eg, the control circuit 240b).

In FIG. 11A, the wireless power receiver 1120 is _{shown to include one switch S 3} , but according to various embodiments, the wireless power receiver 1120 is the switches S ₃ and S _{4 shown in FIG. 2A.} Similarly, it can contain two switches.

According to various embodiments, the control circuit 240b includes a first control for controlling _{at least one first switch (eg, switches S 1} and S ₂ ) included in the wireless power transmitter based on a reference signal. You can check the phase of the signal. According to various embodiments, the control circuit 240b includes a digital microcontroller unit (MCU), converts a reference signal into a digital signal, and processes the reference signal converted into a digital signal using a digital MCU. At least a part of the process of checking the phase of the first control signal may be performed. According to various embodiments, the control circuit 240b includes an analog micro controller unit (MCU), and may perform at least a part of a process of checking the phase of the first control signal from the reference signal by using the analog MCU. .

An example of a specific method of checking the phase of the first control signal based on the reference signal in the control circuit 240b will be described later with reference to FIGS. 11B and 11C. 11B is a diagram illustrating a signal processing process performed by a wireless power receiver according to various embodiments. Referring to FIG. 11B, the wireless power receiver (eg, the wireless power receiver 1120) may include an auxiliary coil 1130 and an MCU 1180. In FIG. 11B, analog elements such as the comparator 1140 and the multiplexer 1150 are included in the MCU 1180, but according to various embodiments, the MCU 1180 may be a digital MCU. 1140 and the multiplexer 1150 do not include analog elements, and the operation of the comparator 1140 and the multiplexer 1150 to be described later may be performed by digital signal processing of the MCU 1180.

11C illustrates various signals identified by the wireless power transmitter and the wireless power receiver according to various embodiments. The first control signal S ₁ may be a signal applied to _{at least one switch (eg, switches S 1} , S ₂ ) included in the wireless power transmitter (eg, wireless power transmitter 1110 ). have. The _{voltage V p} applied to the transmission side including the _{inductor L lkp} , the inductor L _M , and the transmission coil L _P may increase or decrease in synchronization with the first control signal S _1.

_{As the voltage (V p} ) applied to the transmitting side including the inductor (L _lkp ), the inductor (L _M ), and the transmitting coil (L _P ) increases or decreases in synchronization with the first control signal (S _{1 ), the auxiliary} The coil 1130 may _{generate a reference signal V LA} based on a magnetic field generated by the _{transmission coil L P.}

The comparator 1140 may receive a reference signal V _LA and a clamp voltage V _clamp and output a first correction signal Comp. out. The multiplexer 1150 may receive a first correction signal Comp. out and output a sync signal (Event sync.) 1160 in which a pulse exists when the first correction signal Comp. out increases. . When there is a pulse in the sync signal (Event sync.) 1160, since the first control signal S ₁ increases from 0 to a non-zero value, the MCU 1180 is a sync signal (Event sync.) ( Based on 1160), _{the phase of the first control signal S 1} may be checked.

According to various embodiments, the pulse width modulation (PWM) module 1170 included in the MCU 1180 is a time-based counter (TBCTR) that is initialized to 0 when a pulse exists in the sync signal (Event sync.) 1160. ) Signal can be generated. The PWM (pulse width modulation) module 1170 compares the TBCTR (time-based counter) signal with a preset comparison value (CMPA, CMPB), and the TBCTR (time-based counter) signal value is compared with the comparison value (CMPA). When the same, the signal increases from 0 to a non-zero value, and when the value of the TBCTR (time-based counter) signal is the same as the comparison value (CMPB), a signal that falls from a non-zero value to 0 For example, the second control signal S ₃ may be applied to at least one switch (eg, switches S ₃ and S _{4) included in the wireless power receiver 1120.} According to various embodiments, the comparison values CMPA and CMPB may be set according to the phase difference φ between _{the first control signal S 1} and the second control signal S _3. The relationship between the comparison value CMPA and the phase difference φ can be expressed by Equation 3.

In Equation 3, TBPRD may be a period of a pulse in the sync signal (Event sync.) 1160. The phase difference φ may be a value expressed in degrees. Deadtime is when two switches (eg, switches (S ₃ , S ₄ )) included in the wireless power receiver 1120 are included, two switches (S ₃ , S ₄ ) are two for stable switching. It can mean the length of time when everything is off.

The relationship between the comparison value CMPB and the phase difference φ can be expressed by Equation 4.

In Equation 4, definitions of TBPRD, phase difference (φ), and deadtime may be the same as described in Equation 3 above.

The pulse width modulation (PWM) module 1170 applies comparison values (CMPA, CMPB) according to Equation 3 and Equation 4 to a time-based counter (TBCTR) signal synchronized with the sync signal (Event sync.) 1160. By applying, it is possible to generate _{a second control signal S 3} that is delayed by a specific phase difference φ compared to the first control signal S _1. The control circuit (for example, the control circuit 240b) uses _{at least one switch (for example, the second control signal S 3} ) included in the power conversion circuit (for example, the power conversion circuit 220b). For example, _{by applying to the switches (S 3} , S ₄ )), at least one of the current or voltage of the power output from the power conversion circuit 220b may be controlled.

According to various embodiments, the wireless power receiver 1120 includes a control circuit (eg, a control circuit 240b), and the operation of FIG. 8C by the control circuit 240b included in the wireless power receiver 1120 Can be performed. In this case, the operation of checking the phase of the first control signal for controlling at least one first switch included in the wireless power transmitter in operation 810c may include the operations described above with reference to FIGS. 11B and 11C.

As described above with reference to FIGS. 11A to 11C, _{when checking the phase of the first control signal using the auxiliary coil L A} , check the phase of the first control signal through wireless communication with the wireless power transmitter. Compared to this case, it is not necessary to process the signal received through wireless communication from the wireless power transmitter, so it requires less resources of the wireless power receiver, and there is no delay due to signal transmission and signal processing by wireless communication. The output of the power conversion circuit can be controlled.

12 is a diagram illustrating an arrangement of a coil included in a wireless power transmitter and a wireless power receiver according to various embodiments. Specifically, FIG. 12 illustrates a transmission coil 1230 of a wireless power transmitter, a reception coil 1220 of a wireless power receiver, and a wireless power receiver when the wireless power receiver according to various embodiments is receiving wireless power from the wireless power transmitter. The arrangement of the auxiliary coil 1210 of the power receiver is shown. Referring to FIG. 12, the receiving coil 1220 of the wireless power receiver may be disposed substantially parallel to the transmitting coil 1230 of the power transmitter so as to have a cross-section parallel to the cross-section of the transmitting coil 1230 of the power transmitter. . As a current flows in the transmission coil 1230, a magnetic field is generated, and the reception coil 1220 may generate AC power having a voltage proportional to the amount of change over time of the magnetic flux passing through the cross section of the reception coil 1220. .

According to various embodiments, the auxiliary coil 1210 of the wireless power receiver may be disposed to surround at least a portion of the receiving coil 1220. Referring to FIG. 12, the auxiliary coil 1210 of the wireless power receiver may have a cross-section parallel to the cross-section of the transmitting coil 1230 of the power transmitter, similar to the receiving coil 1220. Based on the magnetic field generated as the current flows in the transmission coil 1230, the auxiliary coil 1210 generates AC power having a voltage proportional to the amount of change over time of the magnetic flux passing through the cross section of the auxiliary coil 1210. In addition, at least one of a voltage or current of AC power generated from the auxiliary coil 1210 may be defined as a reference signal.

According to various embodiments, a wireless power receiver for receiving wireless power from a wireless power transmitter includes a resonance circuit configured to generate AC power based on a magnetic field generated by the wireless power transmitter, and the AC power generated by the resonance circuit. A power conversion circuit configured to convert DC power to DC power, and a control circuit, wherein the power conversion circuit includes a first switch, and the control circuit includes a voltage or current of the DC power output from the power conversion circuit. It may be configured to check at least one of and adjust at least one of the voltage or current of the DC power output from the power conversion circuit by adjusting the phase of the first control signal applied to the first switch.

According to various embodiments, the power conversion circuit includes a first diode, a second diode, a third diode, and a fourth diode, and a first terminal of the first diode is connected to a first terminal of the resonance circuit, The second terminal of the first diode is connected to a first output terminal of the power conversion circuit, the first terminal of the second diode is connected to a second terminal of the resonance circuit, and the second terminal of the second diode Is connected to a first output terminal of the power conversion circuit, a first terminal of the third diode is connected to a first terminal of the resonance circuit, and a second terminal of the third diode is connected to a second output terminal of the power conversion circuit Connected, the first end of the fourth diode is connected to the second end of the resonance circuit, the second end of the fourth diode is connected to the first end of the first switch, The second stage may be connected to the second output terminal of the power conversion circuit.

According to various embodiments, the power conversion circuit further includes a second switch, and the control circuit includes phases of the first control signal applied to the first switch and the second control signal applied to the second switch. It may be configured to adjust at least one of a voltage or a current of the DC power output from the power conversion circuit by adjusting.

According to various embodiments, the power conversion circuit includes a first diode, a second diode, a third diode, and a fourth diode, and a first terminal of the first diode is connected to a first terminal of the resonance circuit, The second terminal of the first diode is connected to a first output terminal of the power conversion circuit, the first terminal of the second diode is connected to a second terminal of the resonance circuit, and the second terminal of the second diode Is connected to a first output terminal of the power conversion circuit, a first terminal of the third diode is connected to a first terminal of the resonance circuit, and a second terminal of the third diode is connected to a first terminal of the second switch Connected, the first end of the fourth diode is connected to the second end of the resonance circuit, the second end of the fourth diode is connected to the first end of the first switch, A second terminal may be connected to a second output terminal of the power conversion circuit, and a second terminal of the second switch may be connected to a second output terminal of the power conversion circuit.

According to various embodiments, the power conversion circuit further includes an auxiliary coil configured to generate a reference signal based on a magnetic field generated by the wireless power transmitter, and the control circuit includes the reference signal generated from the auxiliary coil. It may be configured to check the first control signal based on.

According to various embodiments, the auxiliary coil may be disposed to surround at least a portion of a receiving coil included in the resonance circuit.

According to various embodiments, the first control signal may have a first phase difference compared to the reference signal.

According to various embodiments, the control circuit, while the first control signal is applied to the first switch, checks at least one of the voltage or current of the DC power output from the power conversion circuit, and converts the power. In response to determining that at least one of the voltage or current of the DC power output from the circuit is out of a predetermined voltage range and/or a predetermined current range, the second phase difference different from the first phase difference compared to the reference signal It may be configured to apply a third control signal having a to the first switch.

According to various embodiments, the control circuit may include a pulse width modulation (PWM) module, and the control circuit may be configured to generate the first control signal through the PWM module.

According to various embodiments, the control circuit identifies a first event in which the reference signal increases, has the same period as the period of the first event, and has the first phase difference compared to the reference signal. It can be configured to confirm the control signal.

According to various embodiments, the control circuit may be further configured to generate a first correction signal based on the reference signal and to generate a sync signal based on the first correction signal.

According to various embodiments, the power conversion circuit may include a third switch, a fourth switch, a fifth switch, and a sixth switch.

According to various embodiments, a wireless power receiver for receiving wireless power from a wireless power transmitter includes a resonance circuit configured to generate AC power based on a magnetic field generated by the wireless power transmitter, and the AC power generated by the resonance circuit. A power conversion circuit configured to convert DC power to DC power, an auxiliary coil configured to generate a reference signal based on a magnetic field generated by the wireless power transmitter, and a control circuit, wherein the power conversion circuit comprises at least one 1 switch, wherein the control circuit checks a phase of a first control signal for controlling at least one second switch included in the wireless power transmitter, based on the reference signal, and the first control signal Applying a second control signal having a first phase difference of and to the at least one first switch, checking at least one of the voltage or current of the DC power output from the power conversion circuit, and output from the power conversion circuit In response to determining that at least one of the voltage or current of the DC power is out of a predetermined voltage range and/or a predetermined current range, a third having a second phase difference different from the first control signal and the first phase difference It may be configured to apply a control signal to the at least one first switch.

According to various embodiments, a method performed in a wireless power receiver for receiving wireless power from a wireless power transmitter, through a resonance circuit included in the wireless power receiver, generates AC power based on a magnetic field generated by the wireless power transmitter. Generating, converting the AC power into DC power through a power conversion circuit included in the wireless power receiver and including a first switch, and checking at least one of a voltage or a current of the DC power, And adjusting at least one of a voltage or a current of the DC power output from the power conversion circuit by adjusting a phase of the first control signal applied to the first switch.

According to various embodiments, the power conversion circuit further includes a second switch, and the method includes phases of the first control signal applied to the first switch and the second control signal applied to the second switch. By adjusting, the operation of adjusting at least one of the voltage or current of the DC power output from the power conversion circuit may be further included.

According to various embodiments, the power conversion circuit further includes an auxiliary coil configured to generate a reference signal based on a magnetic field generated by the wireless power transmitter, and the voltage of the DC power output from the power conversion circuit or Adjusting at least one of the currents may include checking the first control signal based on the reference signal.

According to various embodiments, the operation of adjusting at least one of the voltage or current of the DC power output from the power conversion circuit includes applying a first control signal having a first phase difference compared to the reference signal to the first switch. It may include an operation to do.

According to various embodiments, the method includes checking at least one of voltage or current of the DC power output from the power conversion circuit while the first control signal is applied to the first switch, and the power In response to determining that at least one of the voltage or current of the DC power output from the conversion circuit is out of a predetermined voltage range or/or a predetermined current range, the second phase difference and the first phase difference compared to the reference signal The operation of applying a third control signal having a two phase difference to the first switch may be further included.

According to various embodiments, the operation of applying the first control signal having a first phase difference compared to the reference signal to the first switch includes an operation of checking a first event in which the reference signal increases, and the first It may include an operation of checking the first control signal having the same period as the period of the event and having the first phase difference compared to the reference signal.

According to various embodiments, the checking of the first event further includes checking a first correction signal based on the reference signal, and checking a sync signal based on the first correction signal. can do.

Claims (20)

1. In the wireless power receiver for receiving wireless power from the wireless power transmitter,

   A resonance circuit configured to generate AC power based on a magnetic field generated by the wireless power transmitter,

   A power conversion circuit configured to convert the AC power generated in the resonance circuit into DC power, and

   Including a control circuit,

   The power conversion circuit includes a first switch,

   The control circuit,

   Check at least one of the voltage or current of the DC power output from the power conversion circuit,

   The wireless power receiver, configured to adjust at least one of a voltage or a current of the DC power output from the power conversion circuit by adjusting a phase of a first control signal applied to the first switch.
2. The method of claim 1,

   The power conversion circuit includes a first diode, a second diode, a third diode, and a fourth diode,

   A first terminal of the first diode is connected to a first terminal of the resonant circuit, a second terminal of the first diode is connected to a first output terminal of the power conversion circuit,

   A first terminal of the second diode is connected to a second terminal of the resonant circuit, a second terminal of the second diode is connected to a first output terminal of the power conversion circuit,

   A first terminal of the third diode is connected to a first terminal of the resonance circuit, a second terminal of the third diode is connected to a second output terminal of the power conversion circuit,

   A first end of the fourth diode is connected to a second end of the resonance circuit, a second end of the fourth diode is connected to a first end of the first switch,

   The second end of the first switch is connected to the second output end of the power conversion circuit, the wireless power receiver.
3. The method of claim 1,

   The power conversion circuit further comprises a second switch,

   The control circuit,

   Configured to adjust at least one of the voltage or current of the DC power output from the power conversion circuit by adjusting the phases of the first control signal applied to the first switch and the second control signal applied to the second switch Being a wireless power receiver.
4. The method of claim 3,

   The power conversion circuit includes a first diode, a second diode, a third diode, and a fourth diode,

   A first terminal of the first diode is connected to a first terminal of the resonant circuit, a second terminal of the first diode is connected to a first output terminal of the power conversion circuit,

   A first terminal of the second diode is connected to a second terminal of the resonant circuit, a second terminal of the second diode is connected to a first output terminal of the power conversion circuit,

   A first end of the third diode is connected to a first end of the resonance circuit, a second end of the third diode is connected to a first end of the second switch,

   A first end of the fourth diode is connected to a second end of the resonance circuit, a second end of the fourth diode is connected to a first end of the first switch,

   A second end of the first switch is connected to a second output end of the power conversion circuit,

   The second end of the second switch is connected to the second output end of the power conversion circuit, the wireless power receiver.
5. The method of claim 1,

   The power conversion circuit further includes an auxiliary coil configured to generate a reference signal based on a magnetic field generated by the wireless power transmitter,

   The control circuit,

   Configured to check the first control signal based on the reference signal generated from the auxiliary coil.
6. The method of claim 5,

   The auxiliary coil is disposed to surround at least a portion of a receiving coil included in the resonance circuit.
7. The method of claim 5,

   The first control signal has a first phase difference compared to the reference signal, the wireless power receiver.
8. The method of claim 7,

   The control circuit,

   While the first control signal is applied to the first switch, check at least one of a voltage or a current of the DC power output from the power conversion circuit,

   In response to determining that at least one of the voltage or current of the DC power output from the power conversion circuit is out of a predetermined voltage range and/or a predetermined current range, the first phase difference is different from the reference signal. A wireless power receiver configured to apply a third control signal having a second phase difference to the first switch.
9. The method of claim 7,

   The control circuit includes a pulse width modulation (PWM) module,

   The control circuit, through the PWM module, is configured to generate the first control signal.
10. The method of claim 9,

    The control circuit,

    Identify a first event in which the reference signal increases,

    And configured to check the first control signal having the same period as the period of the first event and having the first phase difference compared to the reference signal.
11. The method of claim 9,

    The control circuit,

    Generating a first correction signal based on the reference signal,

    Further configured to generate a sync signal based on the first correction signal.
12. The method of claim 1, wherein the power conversion circuit,

    A wireless power receiver comprising a third switch, a fourth switch, a fifth switch, and a sixth switch.
13. A method performed in a wireless power receiver for receiving wireless power from a wireless power transmitter, comprising:

    Generating AC power based on a magnetic field generated by the wireless power transmitter through a resonance circuit included in the wireless power receiver,

    An operation of converting the AC power into DC power through a power conversion circuit included in the wireless power receiver and including a first switch,

    Checking at least one of the voltage or current of the DC power, and

    An operation of adjusting at least one of the voltage or current of the DC power output from the power conversion circuit by adjusting the phase of the first control signal applied to the first switch

    Including, the method.
14. The method of claim 13,

    The power conversion circuit further comprises a second switch,

    The above method,

    An operation of adjusting at least one of the voltage or current of the DC power output from the power conversion circuit by adjusting the phases of the first control signal applied to the first switch and the second control signal applied to the second switch The method further comprising.
15. The method of claim 13,

    The power conversion circuit further includes an auxiliary coil configured to generate a reference signal based on a magnetic field generated by the wireless power transmitter,

    The operation of adjusting at least one of the voltage or current of the DC power output from the power conversion circuit includes checking the first control signal based on the reference signal.
16. The method of claim 15,

    The operation of adjusting at least one of the voltage or current of the DC power output from the power conversion circuit includes an operation of applying a first control signal having a first phase difference compared to the reference signal to the first switch, Way.
17. The method of claim 16,

    The above method,

    While the first control signal is applied to the first switch, checking at least one of a voltage or a current of the DC power output from the power conversion circuit, and

    In response to determining that at least one of the voltage or current of the DC power output from the power conversion circuit is out of a predetermined voltage range or/or a predetermined current range, it is different from the first phase difference compared to the reference signal. And applying a third control signal having the second phase difference to the first switch.
18. The method of claim 16,

    The operation of applying the first control signal having a first phase difference compared to the reference signal to the first switch,

    Confirming a first event in which the reference signal increases, and

    And checking the first control signal having the same period as the period of the first event and having the first phase difference compared to the reference signal.
19. The method of claim 18,

    The operation of confirming the first event,

    An operation of checking a first correction signal based on the reference signal, and

    And verifying a sync signal based on the first correction signal.
20. In the wireless power receiver for receiving wireless power from the wireless power transmitter,

    A resonance circuit configured to generate AC power based on a magnetic field generated by the wireless power transmitter,

    A power conversion circuit configured to convert the AC power generated in the resonance circuit into DC power,

    An auxiliary coil configured to generate a reference signal based on a magnetic field generated by the wireless power transmitter, and

    Including a control circuit,

    The power conversion circuit includes at least one first switch,

    The control circuit,

    Checking the phase of the first control signal for controlling at least one second switch included in the wireless power transmitter based on the reference signal,

    Applying a second control signal having a first phase difference from the first control signal to the at least one first switch,

    Check at least one of the voltage or current of the DC power output from the power conversion circuit,

    In response to determining that at least one of the voltage or current of the DC power output from the power conversion circuit is out of a predetermined voltage range and/or a predetermined current range, the first control signal and the first phase difference are different. A wireless power receiver configured to apply a third control signal having a second phase difference to the at least one first switch.

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