Wireless Charging Power Manager

Abstract

The present invention discloses a wireless charging power manager, including a receiving circuit, a switching power supply chip circuit, a switching tube protection circuit, a high-voltage terminal overcurrent protection circuit, a charging voltage control process circuit, an adapter control unit circuit, and an overload protection circuit for a battery. It is characterized in that: the receiving circuit receives the energy sent by the transmitting coil through the L1 resonant inductance coil. The capacitor C0 and the resonant inductance coil L1 are in parallel resonance, and then in series resonance with the capacitor C0* to further boost the resonant voltage. The present invention can, according to the different relative distances between the transmitting coil and the receiving coil, the transmitting host determines the resonant frequency output at the current distance based on comprehensive parameters such as the output resonant frequency, resonant current, power input current, and power input voltage; triple protection is carried out simultaneously.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless charging, specifically a wireless charging power manager. Background Art

[0002] The increasing number of automobiles has put forward a high demand for energy mainly based on oil and natural gas. However, fossil energy is increasingly depleted, and oil prices will remain high in the long run. At the same time, air pollution caused by automobile exhaust is becoming more and more serious. An electric vehicle uses an on-vehicle power source as power and drives the wheels with an electric motor. Due to its advantages such as energy conservation, environmental protection, and low noise, the prospect of electric vehicles is widely optimistic. However, the development of electric vehicles still faces many technical problems, and the development of charging technology and the deployment of charging stations are important factors among them.

[0003] Battery charging technology is divided into wired charging and wireless charging. For wired charging, the operation mode is similar to that of existing gas stations and requires manual operation by a dedicated person. The disadvantages of this method are obvious. For example, although strict design specifications ensure safety, the charging port is prone to sparking under the impact of high voltage and large current, resulting in device aging; the charging interface components are prone to contamination by dust, rain, fog, oil fume, etc., and monitoring and maintenance are troublesome; from daily experience, the damage rate of high-power sockets is very high, and the sockets of charging stations need to be plugged and unplugged frequently, so the problem will be more serious. Wireless charging technology is a technology that transmits electric energy in the air between a charger and a device through electromagnetic induction or magnetic resonance technology, enabling current to flow to charge the battery.

[0004] This wireless charging method is effectively applied to handheld communication devices, electric vehicles, etc. that require large-capacity battery charging. Moreover, since the connection points are buried underground, there is almost no danger of electric leakage, and problems such as poor connection in the wired charging method can be prevented. Wireless charging can be unattended, hands-free, fully automatic operation, safe and reliable; it can be charged frequently in daily use, improving the battery life and the overall vehicle value after long-term use; medium-power charging has little pressure on the power grid and is convenient for the popular installation of charging devices in parking lots and garages.

[0005] In recent years, the core technology of wireless charging has become increasingly mature. The wireless charging efficiency can already exceed 90%, the wireless charging power can reach 30 kw, and the wireless charging distance can reach the meter level. However, how to solve the compatibility between in-vehicle devices and charging piles to improve charging safety and avoid accidents, and how to manage in-vehicle charging devices to prevent illegal users and in-vehicle charging devices from stealing electricity are still problems faced by the wireless charging industry. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a wireless charging power manager to improve the safety of wireless charging and prevent electricity theft.

[0007] To solve the above problems, the present invention is implemented by the following technical solutions: A wireless charging power manager, including a receiving circuit, a switching power supply chip circuit, a switching tube protection circuit, a high-voltage end overcurrent protection circuit, a charging voltage control process circuit, an adapter control unit circuit, and an overload protection circuit for the battery, characterized in that: the receiving circuit receives the energy sent by the transmitting coil through the L1 resonant inductor coil, the capacitor C0 and the resonant inductor coil L1 are in parallel resonance, and then form a series resonance with the capacitor C0* to further increase the resonant voltage. After resonance, a high-frequency full-wave rectifier bridge composed of diodes D1, D2, D3, and D4 converts the high-frequency changing magnetic energy into direct current. After rectification, a high voltage of several thousand volts is obtained. In order to reduce this high voltage, resistors R0 and R0* are used to limit this high voltage.

[0008] The transmitting coil L emits magnetic energy to the receiving coil L1. In the initial stage when the subsequent circuit has not been established to work, the subsequent circuit is equivalent to an open circuit for the rectified output. An open circuit means that a high voltage of thousands of volts is output to the outside. The device working parameters of the subsequent adapter cannot meet such a high voltage. Therefore, a two-stage resistor limiting mode is adopted. In addition, the diode D17 in the circuit prevents the high voltage from returning and surging when the subsequent switching power supply is turned off, thus generating a higher voltage. D18 provides a voltage and current discharge loop when the subsequent Q1 switching tube is turned off.

[0009] L1 is a resonant inductor coil, C0 and C0* are capacitors, D1, D2, D3, D4, D17, and D18 are diodes, and R0 and R0* are resistor combination circuit forms.

[0010] The aforementioned wireless charging power manager is characterized in that: the DC voltage output by the diode D17 is 650V - 850V, passes through the FU 3A fuse and the T 5D11 thermal start resistor, and passes through two 550v120uf electrolytic capacitors C1 and C2 connected in series with each other. The series voltage division of the aforementioned two electrolytic capacitors can reach a maximum withstand voltage of 1100V, and is loaded onto the drain of the field effect transistor Q1 MSFET P-channel regulator through the switching transformer T1. The withstand voltage of Q1 is 1200V 3A; the other path is loaded onto the 7th pin of the power switch chip UC3842E through the R3 250k start resistor. The UC3842 internally has an undervoltage lockout circuit, and the on and off thresholds are 16V and 10V.

[0011] Before turning on, the current consumed by UC3842 is less than 1mA. After starting, the normal working current is 15mA. Once this pin has a working voltage, the internal reference voltage generator of the device generates a 5V reference voltage. The reference voltage is output from the 8th pin of the chip. C5 is the reference voltage filter capacitor. The RC oscillation circuit composed of R6, C6, and the 4th pin of the chip starts to vibrate. The PWM output from the 6th pin of the chip is loaded to the gate of Q1 MSFET through the series R4* and R4. The high and low voltage pulses formed by PWM, during the high pulse period, the field effect tube is turned on, the current passes through the primary side of the transformer, and the energy is stored in the transformer. According to the same-name terminal, there is no energy output on the secondary side of the transformer at this time. When the 6th pin outputs a high level, the field effect tube is turned off. According to Lenz's law, the primary side of the transformer generates an induced electromotive force with positive and negative in the lower side to maintain the current unchanged. At this time, the diodes on the secondary side are turned on to provide voltage and current to the outside. D8 is turned on and filtered by the C5* high-frequency filter and the C4 electrolytic capacitor to form a continuous working current to provide working conditions for the switching power supply chip.

[0012] The energy stored in the primary winding of the high-frequency transformer during the conduction period of the field effect tube is equal to the energy released by the secondary winding during the shutdown period of the field effect tube. The output voltage UO is proportional to the Ton turn-on time and inversely proportional to the turns ratio N and the Toff turn-off time. When the output voltage is too low due to changes in the power supply voltage or load changes, the feedback is controlled by the PC1 optocoupler. Pin C8 of UC38421 is a de-noising capacitor and R7 is a pull-down resistor. The PWM duty cycle is controlled by internal calculation, and the PWM duty cycle is increased to prolong the conduction time of the Q1 high-power transistor; on the contrary, when the power supply voltage changes or the load changes and causes the output voltage to increase, the pulse width modulator will correspondingly reduce the duty cycle of the PWM output waveform, thereby shortening the conduction time of the power tube Q1 and maintaining it within a certain voltage range.

[0013] The aforementioned wireless charging power manager is characterized in that: the switch tube protection circuit is composed of D5 Schottky diode, R1 47K resistor, C3 470pf 1000V capacitor, R, C, D spike absorption and R0*, D18 form a double discharge circuit to protect Q1 turn-off time and reverse voltage absorption without damaging the tube, R10 is the Q1 power tube gate pull-down resistor.

[0014] The aforementioned wireless charging power manager is characterized in that: R2 in the high-voltage end overcurrent protection circuit is a current sampling resistor. When the output load is too heavy for some reason, the voltage on R2 increases. The voltage and the voltage divider circuit composed of R9 and R8 will increase the voltage of UC3842 pin 3. After internal processing of the chip, the output PWM becomes narrower, thereby reducing the output.

[0015] The aforementioned wireless charging power manager is characterized in that: in the charging voltage control process circuit, when D7 and D15 are forward-conducting, the charging voltage output and the voltage for the operation of the backend BMS are established. The DC 24V voltage output by D7 is filtered by C01 high-frequency filter and C11 electrolytic capacitor to generate the operating voltage. The first path is limited in current by R39 and R40 and added to the positive electrode of the cooling fan. The second path is loaded onto the base of Q3, and its control terminal obtains the conduction voltage, forming a switch connection so that the fan rotates. The third path is loaded onto the collector of Q2. R31 is the upper bias resistor and the V2F reference outputs a 5V operating voltage. R32 and R29 are used for voltage division to obtain a 2.5V reference voltage. C04 is the reference voltage noise elimination capacitor. The fourth path is loaded onto R12, and the voltage division of R12 and R11 is controlled by the reference voltage of V1F. The increase or decrease in voltage caused by the change in the output load is controlled by the feedback of the PC817 optocoupler to adjust the PWM duty cycle output of the primary side, thereby achieving the adjustment purpose.

[0016] RT2 is close to D15. After charging, as time increases, the temperature of RT2 gradually rises. The resulting voltage change is output through UE1 BMS OUT3 to control the PC817 to adjust the PWM output of the primary side to offset the influence brought by the temperature change.

[0017] C18 and R50 are for the RC absorption circuit to protect D15. The 85V voltage output after D15 rectification is filtered by C17 and then voltage-divided by R24, R25, R21, R22, R23, R23* and superimposed with the D7 voltage to provide the operating voltage for UE1 BMS. At the same time, it also forms the V1F reference voltage with R17, R18, R16, R15, R14, R13, R13* to constitute the PWM feedback control of PC1 for the primary side. C9 and C12 are high-frequency noise elimination capacitors, which are used to purify the V1F reference voltage to prevent clutter interference.

[0018] The aforementioned wireless charging power manager is characterized in that: in the adapter control unit circuit, the adapter control unit UE1 BMS MCU outputs an adjustment instruction, and controls the output of the charger to the battery through the BUCK synchronous rectification circuit. The BUCK synchronous buck rectification circuit composed of Q4, L2, Q5, Q6, and Q7 controls the charging current and voltage. R62 1k is the gate drive resistor of Q4, R63 is the gate pull-up resistor, R64 is the gate pull-down resistor, and Q6 controls the gate drive pulse. R61 is the base drive resistor of Q6. R66 1k is the gate drive resistor of Q5, R67 is the gate pull-up resistor, R68 is the gate pull-down resistor, and Q6 controls the gate drive pulse. R65 is the base drive resistor of Q6. D16 is the reverse connection prevention diode, which protects the power adapter from being burned out due to the reverse connection of the battery positive and negative poles.

[0019] The aforementioned wireless charging power manager is characterized in that: when the D16 charges the battery, the loop current passes through the 0.1R resistor R61 and the voltage dividing circuit composed of R28 and R27 and is input to pin 2 of the UE1 BMS. After internal operation control, the OUT1 and OUT2 PWM outputs control the output of the BUCK circuit. When the output current increases due to some reason, since there is a sampling resistor R61, the voltage across its two ends will also increase, and correspondingly, the voltage of pin 2 of the UE1 BMS will also increase. Through internal operation adjustment, the pulse width of the OU1 and OUT2 PWM is reduced to reduce the current output. Assume that the load is short-circuited at this time. Due to the short-circuit current, the voltage across R61 will increase rapidly, and this value is much larger than the normally increased current. Reflected to pin 2 of the UE1, the UE1 will simultaneously send a shutdown signal. One way is to control the source side of OUT3 to shut down the output, and the other way is to control the OUT1 and OUT2 to shut down the PWM output and turn off the resonance frequency output of the transmitting coil.

[0020] The present invention can determine the resonance frequency output at the current distance according to the comprehensive parameters such as the output resonance frequency, resonance current, power input current, and power input voltage based on the different relative distances between the transmitting coil and the receiving coil; at the same time, triple protection is almost carried out simultaneously. At the same time, it notifies the background adapter that a short-circuit phenomenon has occurred and needs to be processed, and the staff will contact and communicate with the customer to discuss the handling matters. Description of the Drawings

[0021] Figure 1 It is the circuit schematic diagram of the present invention. Detailed Embodiments

[0022] The following further elaborates on the present invention in conjunction with the description of the drawings.

[0023] The wireless charging power manager includes a receiving circuit, a switching power supply chip circuit, a switching tube protection circuit, a high-voltage end overcurrent protection circuit, a charging voltage control process circuit, an adapter control unit circuit, and an overload protection circuit for the battery. It is characterized in that: the receiving circuit receives the energy sent by the transmitting coil through the L1 resonance inductance coil. The capacitor C0 and the resonance inductance coil L1 are in parallel resonance, and then form a series resonance with the capacitor C0* to further boost the resonance voltage. After resonance, a high-frequency full-wave rectifier bridge composed of diodes D1, D2, D3, and D4 converts the high-frequency changing magnetic energy into direct current. After rectification, a high voltage of several thousand volts is obtained. In order to reduce this high voltage, resistors R0 and R0* are used to limit this high voltage.

[0024] The transmitting coil L emits magnetic energy to the receiving coil L1. When the back-end circuit has not been established at the initial stage, the back-end circuit is equivalent to an open circuit for the rectified output. An open circuit means that a high voltage of thousands of volts is output externally, and the device operating parameters of the back-end adapter cannot meet such a high voltage. Therefore, a two-stage resistance limiting mode is adopted. In addition, the diode D17 in the circuit prevents the high voltage from returning and surging back when the back-end switching power supply is turned off, thus generating a higher voltage. D18 provides a voltage and current discharge loop when the Q1 switching tube in the back-end is turned off.

[0025] L1 is a resonant inductance coil, C0 and C0* are capacitors, D1, D2, D3, D4, D17, and D18 are diodes, and R0 and R0* are resistor combination circuit forms.

[0026] The aforementioned wireless charging power manager is characterized in that: the DC voltage output by the diode D17 is 650V - 850V, passing through the FU 3A fuse and the T 5D11 thermistor starting resistor, and then through two 550v120uf electrolytic capacitors C1 and C2 connected in series. The series voltage division of the two aforementioned electrolytic capacitors can reach a maximum withstand voltage of 1100V, and is loaded onto the drain of the Q1 MSFET P-channel regulator through the switching transformer T1. The withstand voltage of Q1 is 1200V 3A; the other path is loaded onto the 7th pin of the power switch chip UC3842E through the R3 250k starting resistor. The UC3842 internally has an undervoltage lockout circuit, and the on and off thresholds are 16V and 10V.

[0027] Before startup, the current consumed by UC3842 is within 1mA, and the normal operating current after startup is 15mA. Once this pin has a working voltage, the internal reference voltage generator of the device generates a 5V reference voltage, which is output from the 8th pin of the chip. C5 is the reference voltage filter capacitor. The RC oscillator circuit composed of R6, C6, and the 4th pin of the chip starts to oscillate. The PWM output from the 6th pin of the chip is loaded onto the gate of the Q1 MSFET through the series-connected R4* and R4. The high and low voltage pulses formed by the PWM turn on the field effect transistor during the high pulse period, and the current passes through the primary side of the transformer, and at the same time, energy is stored in the transformer. According to the situation of the same-name terminals, no energy is output from each secondary side of the transformer at this time. When the high level output from the 6th pin ends, the field effect transistor is turned off. According to Lenz's law, the primary side of the transformer generates an induced electromotive force with the lower part positive and the upper part negative to maintain the current unchanged. At this time, the diodes on each secondary side conduct, providing voltage and current outward. D8 conducts and is filtered by the C5* high-frequency filter and the C4 electrolytic capacitor to form a continuous working current to provide the working conditions for the switching power supply chip.

[0028] During the conduction period of the field-effect transistor, the energy stored in the primary winding of the high-frequency transformer is equal to the energy released by the secondary winding during the off period of the field-effect transistor. The output voltage UO is proportional to the on time Ton and inversely proportional to the turns ratio N and the off time Toff. When the output voltage is too low due to changes in the power supply voltage or load, the feedback is controlled by the PC1 optocoupler. UC3842 pin 1 is connected to C8 which is a noise suppression capacitor, and R7 is a pull-down resistor. The internal operation controls the PWM duty cycle. Increasing the PWM duty cycle makes the conduction time of the Q1 high-power transistor longer; conversely, when the output voltage increases due to changes in the power supply voltage or load, the pulse width modulator will correspondingly decrease the duty cycle of the PWM output waveform, thereby shortening the conduction time of the power transistor Q1 and maintaining it within a certain voltage range.

[0029] The aforementioned wireless charging power supply manager is characterized in that: the switching transistor protection circuit consists of a D5 Schottky diode, a 47K R1 resistor, and a 470pf 1000V C3 capacitor. The R, C, D spike absorption and the double discharge circuit formed by R0* and D18 protect the turn-off time of Q1 and absorb the reverse voltage so as not to damage the transistor. R10 is the pull-down resistor for the gate of the Q1 power transistor.

[0030] The aforementioned wireless charging power supply manager is characterized in that: in the high-voltage end overcurrent protection circuit, R2 is the current sampling resistor. When the output load is too heavy due to some reason, the voltage on R2 increases. This voltage and the voltage dividing circuit composed of R9 and R8 will cause the voltage of UC3842 pin 3 to increase. After internal processing by the chip, the output PWM becomes narrower, thereby reducing the output.

[0031] The aforementioned wireless charging power supply manager is characterized in that: in the charging voltage control process circuit, when D7 and D15 are forward-conducting, the charging voltage output and the voltage for the operation of the backend BMS are established. The DC 24V voltage output by D7 is filtered by C01 high-frequency filter and C11 electrolytic capacitor to generate the working voltage. The first path is limited by R39 and R40 and added to the positive pole of the cooling fan. The second path is added to the base of Q3. Its control terminal gets the conduction voltage, forming a switch connection so that the fan rotates. The third path is added to the collector of Q2. R31 is the upper bias resistor and the V2F reference outputs a 5V working voltage. R32 and R29 are voltage-divided to get a 2.5V reference voltage. C04 is the noise suppression capacitor for the reference voltage. The fourth path is added to R12. R12 and R11 are voltage-divided and controlled by the reference voltage of V1F. Due to the voltage increase or decrease caused by the change of the output load, the PWM duty cycle output of the primary side is controlled by the feedback of the PC817 optocoupler to achieve the adjustment purpose.

[0032] RT2 is close to D15. After the temperature control thermistor RT2 is charged, its temperature gradually rises as time increases. The resulting voltage change is output through UE1 BMS OUT3 to control PC817 to adjust the PWM output on the primary side to offset the influence brought by the temperature change.

[0033] C18 and R50 are for the RC absorption circuit to protect D15. The 85V voltage output after D15 is rectified is filtered by C17 and then divided by R24, R25, R21, R22, R23, R23* and superimposed with the voltage of D7 to provide the working voltage for UE1 BMS. At the same time, it also forms the V1F reference voltage with the voltages of R17, R18, R16, R15, R14, R13, R13* to constitute the PWM feedback control of PC1 on the primary side. C9 and C12 are high-frequency noise elimination capacitors, which are used to purify the V1F reference voltage to prevent clutter interference.

[0034] The aforementioned wireless charging power manager is characterized in that: for the adapter control unit circuit, the adapter control unit UE1 BMS MCU outputs an adjustment instruction to control the output of the charger to the battery through the BUCK synchronous rectification circuit. The BUCK synchronous buck rectification circuit composed of Q4, L2, Q5, Q6, Q7 controls the charging current and voltage. R62 1k is the gate drive resistor of Q4, R63 is the gate pull-up resistor, R64 is the gate pull-down resistor, Q6 controls the gate drive pulse, and R61 is the base drive resistor of Q6. R66 1k is the gate drive resistor of Q5, R67 is the gate pull-up resistor, R68 is the gate pull-down resistor, Q6 controls the gate drive pulse, and R65 is the base drive resistor of Q6. D16 is an anti-reverse connection diode to protect the power adapter from being burned out due to the reverse connection of the battery positive and negative poles.

[0035] The aforementioned wireless charging power manager is characterized in that: for the overload protection circuit of the battery, when D16 charges the battery, the loop current passes through the R61 0.1R resistor and the voltage dividing circuit composed of R28 and R27 and is input to pin 2 of UE1 BMS. It is output through the internal operation control OUT1 OUT2 PWM to control the output of the BUCK circuit. When the output current increases for some reason, due to the R61 sampling resistor, the voltage across its two ends will also increase, and the voltage of pin 2 of the corresponding UE1 BMS will also increase. The PWM pulse width of OU1 OUT2 is adjusted through internal operation to reduce the current output. Assume that the load is short-circuited at this time. Due to the short-circuit current, the voltage across R61 will increase rapidly, which is much larger than the ordinary increased current. Reflected to pin 2 of UE1, UE1 will send a shutdown signal to OUT3 to control the source side to shut down the output, and the other path controls OUT1 OUT2 to shut down the PWM output and turn off the transmission of the resonant frequency of the coil.

[0036] Working process: When the adapter is connected to the battery, a voltage dividing circuit composed of R35 5.1M, R35* 5.1M, and R35** 220K detects the voltage of the current battery to distinguish whether the voltage type of the current battery is 48V, 60V, or 72V. The battery type code can also be downloaded together when the identification code is downloaded, and the battery AH number at the current stage is not currently concerned. Since the adapter is always connected to the battery, a unique identification code and a feature code are loaded during the initial installation. The identification code is generated randomly and stored locally in the adapter UE1 BMS EEPRO. It is loaded by the upper computer and uploaded to the background database remotely. During charging, the unique identification code and the feature code of this group of batteries are authenticated. If there is only a feature code without a unique identification code, charging is allowed for 3 minutes and a text message is sent to inform. The unique identification code can be downloaded online through the WeChat mini-program. (A cracked adapter does not have a unique identification code. The unique identification code is stored in the network server database and the local BMS EEPROM. Assuming it is cracked, the system will lock this device based on the usage situation of previous charging users. When a second user with the same situation is detected, the background will give an alarm and send personnel to the site for on-site confirmation.) This facilitates the identification of the adapter's identity and thus solves the problem that for different electric vehicles, a user may move another vehicle away and replace it with their own vehicle to charge at the same location. Even if they replace it with their own vehicle to charge, since the previous user's charging is not completed and the unique identification code is confirmed by the system, charging will not be allowed. At the same time, a text message will also remind the user that the vehicle may have been removed from the charging area.

[0037] If, for some reason, the system power fails during the charging process, for users who are charging and have not completed the charging and have not left the charging area, the system will continue to complete the remaining charging when the power comes back on.

[0038] Wireless charging establishment process: When the user parks the vehicle in place within a certain charging position area and pays by scanning the QR code on the WeChat mini-program, the host receives the startup charging instruction. First, the host's transmitting coil L emits a test resonance pulse, which is received by the receiving coil L1. Based on the power voltage, input current, high-frequency current, and the current output resonance frequency detected by the host's output feedback, the collected data array is analyzed and parsed to determine the distance between the current transmitting coil and the receiving coil, thereby determining the PWM frequency value of the resonance pulse to be output at the current distance. After entering the steady state period, the adapter sends an online signal, which is output from pin 3 of UE1 BMS. A low level time of 50 ms represents 0 and a high level time of 30 ms represents 1. An online data packet is sent. After the host receives the online data packet, it will reduce the transmission power. (Reducing the transmission power helps reduce the resonance voltage and is also beneficial for data transmission). The adapter will transmit the charging current, battery voltage, unique identification code, and machine feature code during normal charging back to the host. After the host receives it, it records the current information situation and resumes to the normal charging power output state after 150 ms. During the charging process, do not touch the vehicle to cause displacement. If the host detects that the distance between the transmitting coil and the receiving coil is too close, it will stop output for protection. When the distance is too close and the output is still at the original output level, it will cause the output resonance voltage to be too high and damage the adapter. If the host detects that the distance between the transmitting coil and the receiving coil is too far, it will also stop the machine for protection. When the distance is too far, the charging current is too small and the charging time is too long. When the host of the transmitting coil detects that the distance between the transmitting coil and the receiving coil exceeds 8 cm, it will not be able to charge the electric vehicle due to exceeding the charging range.

[0039] Overload protection process of the battery: When D16 charges the battery, the loop current passes through the 0.1R resistor R61 and the voltage division circuit composed of R28 and R27 and is input to pin 2 of UE1 BMS. After internal operation control, OUT1, OUT2, and PWM output control the BUCK circuit output. When the output current increases for some reason, due to the R61 sampling resistor, the voltage across its two ends will also increase, and the voltage at pin 2 of UE1 BMS will also increase accordingly. Through internal operation adjustment, the pulse width of OU1, OUT2, and PWM is reduced to reduce the current output. Assume that the load is short-circuited at this time. Due to the short-circuit current, the voltage across R61 will increase rapidly, and this value is much larger than the normal increased current. Reflected to pin 2 of UE1, UE1 will send a shutdown signal to control the source side to shut down the output and control the PWM output of OUT1 and OUT2 to shut down at the same time. At the same time, the host of the transmitting coil also detects the output abnormality and closes the resonance frequency output of the transmitting coil; triple protection is carried out almost simultaneously.

Claims

1. A wireless charging power manager, comprising a receiving circuit, a switching power supply chip circuit, a switching tube protection circuit, a high-voltage end overcurrent protection circuit, a charging voltage control process circuit, an adapter control unit circuit, and an overload protection circuit for a battery, characterized in that: The receiving circuit receives the energy sent by the transmitting coil through the resonant inductor coil L1. The capacitor C0 and the resonant inductor coil L1 are in parallel resonance, and then in series resonance with the capacitor C0* to further boost the resonant voltage. After resonance, a high-frequency full-wave rectifier bridge composed of diodes D1, D2, D3, and D4 converts the high-frequency changing magnetic energy into direct current. After rectification, a high voltage of several thousand volts is obtained. To reduce this high voltage, resistors R0 and R0* are used to limit this high voltage. In the initial stage when the subsequent circuit has not started working, the subsequent circuit is equivalent to an open circuit for the rectified output. The device operating parameters of the subsequent adapter cannot withstand the high voltage, so a two-stage resistor limiting mode is adopted. In the circuit, the diode D17 prevents the high voltage from returning and surging when the subsequent switching power supply is turned off, resulting in a higher superimposed voltage. In the circuit, the diode D18 provides a voltage and current discharge loop when the subsequent Q1 switching transistor is turned off. Among them, the DC voltage output by the diode D17 is 650V - 850V. It passes through the F1 3A fuse and the T5D11 thermistor starting resistor, and then through two 550v 120uf electrolytic capacitors C1 and C2 connected in series. The series voltage division of the two electrolytic capacitors can withstand a maximum voltage of 1100V, and is applied to the drain of the field effect transistor Q1 MSFET P-channel regulator through the switching transformer T1. The withstand voltage of Q1 is 1200V 3A. Another path is loaded to the 7th pin of the power switch chip UC3842E through the R3 250k starting resistor. The UC3842 internally has an undervoltage lockout circuit, and the on and off thresholds are 16V and 10V. In the charging voltage control process circuit, when D7 and D15 are forward-conducting, the charging voltage output and the voltage for the subsequent BMS to work are established. The DC 24V voltage output by D7 is filtered by the C01 high-frequency filter and the C11 electrolytic capacitor to generate the working voltage. The first path is limited by R39 and R40 and applied to the positive pole of the cooling fan. The second path is loaded to the base of Q3, and its control terminal obtains the conduction voltage, forming a switch connection to make the fan run. The third path is loaded to the collector of Q2. R31 is the upper bias resistor and the V2F reference outputs a 5V working voltage. R32 and R29 are voltage-divided to obtain a 2.5V reference voltage. C04 is the noise elimination capacitor for the reference voltage. The fourth path is loaded to R12. The voltage division of R12 and R11 is controlled by the reference voltage of V1F. The increase or decrease of the voltage caused by the change of the output load is controlled by the feedback of the PC817 optocoupler to adjust the PWM duty cycle output of the primary side, thereby achieving the adjustment purpose.

2. The wireless charging power manager according to claim 1, wherein: The current consumed by the UC3842 before it is turned on is within 1mA, and the normal working current after startup is 15mA. Once this pin has a working voltage, the internal reference voltage generator of the device generates a 5V reference voltage, and the reference voltage is output by the 8th pin of the chip. C5 is a reference voltage filter capacitor. The RC oscillation circuit composed of R6, C6, and the 4th pin of the chip starts to vibrate. The PWM output by the 6th pin of the chip is loaded to the gate of Q1MSFET through the series connection of R4* and R4. The high and low voltage pulses formed by PWM, during the high pulse period, the field effect tube is turned on, and the current passes through the primary side of the transformer, and the energy is stored in the transformer; according to the situation of the same-name terminal, there is no energy output on the secondary sides of the transformer at this time; when the 6th pin outputs a high current When the voltage is flat, the field effect tube is cut off. According to Lenz's law, the primary side of the transformer generates an induced electromotive force with positive and negative induced electromotive force to maintain the current. At this time, the diodes on the secondary side are turned on to provide voltage and current to the outside; D8 is turned on and filtered by C5* high-frequency filter C4 electrolytic capacitor to form a continuous working current to provide working conditions for the switching power supply chip; the energy stored in the primary winding of the high-frequency transformer during the field effect tube conduction period is equal to the energy released by the secondary winding during the field effect tube shutdown period. The output voltage UO is proportional to the Ton turn-on time and inversely proportional to the turns ratio N and Toff turn-off time. When the output voltage is too low due to changes in the power supply voltage or load changes, the feedback is controlled by the PC1 optocoupler UC3842 Pin 1 C8 is a de-noising capacitor and R7 is a pull-down resistor. The PWM duty cycle is controlled by internal calculation. Increasing the PWM duty cycle will prolong the conduction time of the Q1 high-power transistor. Conversely, when the power supply voltage changes or the load changes and causes the output voltage to increase, the pulse width modulator will correspondingly reduce the duty cycle of the PWM output waveform, thereby shortening the conduction time of the power tube Q1 and maintaining it within the voltage range.

3. The wireless charging power manager according to claim 1, characterized in that: The switch tube protection circuit is composed of D5 Schottky diode, R1 47K resistor, C3 470pf 1000V capacitor, R, C, D spike absorption and R0*, D18 formed double discharge circuit to protect Q1 turn-off time and reverse voltage absorption without damaging the tube, R10 is the Q1 power tube gate pull-down resistor.

4. The wireless charging power manager according to claim 1, characterized in that: In the high-voltage overcurrent protection circuit, R2 is a current sampling resistor. When the output load is too heavy for some reason, the voltage on R2 increases. The voltage and the voltage divider circuit composed of R9 and R8 will increase the voltage of pin 3 of UC3842. After internal processing of the chip, the output PWM becomes narrower, thereby reducing the output.

5. The wireless charging power supply manager according to claim 4, characterized in that: The temperature control thermistor RT2 is close to D15. After the temperature control thermistor RT2 is charged, its temperature gradually rises with the increase of time. The voltage change caused is output through UE1 BMS OUT3 to control PC817 to adjust the PWM output of the primary side to offset the influence brought by the temperature change; C18 and R50 are used as an RC absorption circuit to protect D15; the 85V voltage output after D15 is rectified is filtered by C17 and divided by R24, R25, R21, R22, R23, R23* and then superimposed with the D7 voltage to provide the working voltage for UE1 BMS. At the same time, it also forms a V1F reference voltage with the voltages of R17, R18, R16, R15, R14, R13, R13* to constitute the PWM feedback control of PC1 on the primary side. C9 and C12 are high-frequency noise elimination capacitors, which are used to purify the V1F reference voltage to prevent clutter interference.

6. The wireless charging power supply manager according to claim 1, wherein: The adapter control unit circuit: The adapter control unit UE1 BMS MCU outputs an adjustment instruction to control the output of the charger to the battery through the BUCK synchronous rectification circuit. The BUCK synchronous buck rectification circuit composed of Q4, L2, Q5, Q6, and Q7 controls the charging current and voltage. R62 1k is the gate drive resistor of Q4, R63 is the gate pull-up resistor, and R64 is the gate pull-down resistor. Q6 is controlled by the gate drive pulse, and R61 is the base drive resistor of Q6; R66 1k is the gate drive resistor of Q5, R67 is the gate pull-up resistor, and R68 is the gate pull-down resistor. Q6 is controlled by the gate drive pulse, and R65 is the base drive resistor of Q6; D16 is an anti-reverse connection diode to protect the power adapter from being burned out due to the reverse connection of the battery positive and negative poles.

7. The wireless charging power manager according to claim 1, wherein: When the battery overload protection circuit charges the battery through D16, the loop current is input to pin 2 of UE1 BMS through the R61 0.1R resistor and the voltage dividing circuit composed of R28 and R27, and the internal operation control OUT1 OUT2 PWM output controls the output of the BUCK circuit. When the output current increases due to some reason, because there is a R61 sampling resistor, the voltage across its two ends will also increase, and the voltage of pin 2 of UE1 BMS will also increase accordingly. The internal operation adjusts to reduce the OU1 OUT2 PWM pulse width, thereby reducing the current output. When the load is short-circuited, the short-circuit current will cause the voltage across R61 to increase rapidly, which is much larger than the ordinary increased current. Reflected to pin 2 of UE1, UE1 will simultaneously send a shutdown signal. One way is to control the source side to shut down the output through OUT3, and the other way is to control OUT1 OUT2 to shut down the PWM output and turn off the resonance frequency output of the transmitting coil.

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