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CN-115811152-B - Working method of wireless charging system

CN115811152BCN 115811152 BCN115811152 BCN 115811152BCN-115811152-B

Abstract

The invention discloses a working method of a wireless charging system, which comprises the steps of placing equipment, judging the position of a coil, and loading frequency on an exciting coil to be The power judgment comprises counting the total working power of all the working transmitting units, starting wireless charging if the charging power requirement of the equipment to be charged is met, otherwise, performing metal foreign matter detection, wherein the loading working frequency of the exciting coil is The invention judges whether the metal foreign matter exists or not, and the corresponding transmitting unit is used as a working transmitting unit under the condition of receiving coils and is started in the subsequent wireless charging. Since there are more transmitting units, the device to be charged has more position choices, has a choice of a larger offset range, changes the frequency of the signal applied to the exciting coil, and can also be used for detecting metallic foreign matters.

Inventors

  • WANG ZHE
  • LU JUN
  • HE FANBO
  • GE JUNJIE
  • MA JUNCHAO

Assignees

  • 合肥有感科技有限责任公司

Dates

Publication Date
20260508
Application Date
20230103

Claims (7)

  1. 1. A method of operating a wireless charging system, comprising: placing equipment, namely placing equipment to be charged into a charging area; the coil position judgment comprises the steps of sequentially connecting each transmitting unit into a circuit by a control switch, connecting the transmitting units in parallel with a first transmitting unit to form a circuit, always coupling an exciting coil (1) with the first transmitting unit, and loading the exciting coil (1) with the frequency of The alternating current signal is used for judging whether a receiving coil (51) of the equipment to be charged is arranged above an accessed transmitting unit, if so, the corresponding transmitting unit is used as a working transmitting unit, and the other receiving coil is a non-working transmitting unit, wherein L D2 is an equivalent inductance after each time of accessing the transmitting unit and comprises an equivalent inductance formed by a first transmitting unit, the accessed transmitting unit, an exciting coil (1) and the receiving coil (51), and C D2 is an equivalent capacitance after each time of accessing the transmitting unit and comprises an equivalent capacitance of the first transmitting unit and the accessed transmitting unit; The power judgment comprises the steps of counting the total working power of all the working transmitting units, starting wireless charging if the charging power requirement of equipment to be charged is met, and otherwise, detecting metal foreign matters; The metal foreign matter detection comprises keeping the first control switch of the first transmitting unit closed, sequentially switching on the control switch of the non-working transmitting unit, and loading working frequency on the exciting coil (1) To determine whether the corresponding transmitting unit is misjudged as a non-working transmitting unit due to metal foreign matters, wherein L D3 is an equivalent inductance after the non-working unit is connected, and C D3 is an equivalent capacitance after the non-working unit is connected.
  2. 2. The method according to claim 1a method for operating a wireless charging system, it is characterized in that the method comprises the steps of, The first transmitting unit is positioned at a charging center position, and when the equipment to be charged is placed in a charging area, the receiving coil (51) and the first transmitting unit are always in a couplable state.
  3. 3. According to claim 2a method for operating a wireless charging system, it is characterized in that the method comprises the steps of, The first transmitting unit is coupled to the receiving coil (51) and is further configured for information transmission, the transmitted information including at least one of a charging request, a charging power requirement, and a stop charging notification.
  4. 4. The method according to claim 1a method for operating a wireless charging system, it is characterized in that the method comprises the steps of, In coil position determination, the loading operating frequency is After comparing the first phase difference of the two parameters: parameter 1 is the voltage of the alternating current signal applied to the excitation coil (1); Parameter 2, total current of a circuit formed by connecting the first transmitting unit and the transmitting unit where the control switch (S) is closed each time in parallel; When the value of the first phase difference is in a first threshold range or a second threshold range, a receiving coil (51) is arranged at the position of the corresponding transmitting unit, otherwise, the receiving coil (51) is not arranged; Presetting a phase difference threshold value phi T , and dividing a first threshold range and a second threshold range: the first threshold range is [0 °, Φ T ]; The second threshold range is [ Φ T ', 360 ° ], where Φ T '=360°-Ф T .
  5. 5. The method according to claim 1a method for operating a wireless charging system, it is characterized in that the method comprises the steps of, In the detection of metallic foreign matters, the loading working frequency is After the ac signal of (c) and then comparing the third phase difference of the following two parameters: Parameter 5, voltage of the alternating current signal applied to the exciting coil (1); parameter 6, total current of a circuit formed by connecting the first transmitting unit and the transmitting unit of the control switch S which is closed each time in parallel; When the value of the third phase difference is in the first threshold range or the second threshold range, judging that no metal foreign matter exists, otherwise, judging that the metal foreign matter exists; Presetting a phase difference threshold value phi T , and dividing a first threshold range and a second threshold range: the first threshold range is [0 °, Φ T ]; The second threshold range is [ Φ T ', 360 ° ], where Φ T '=360°-Ф T .
  6. 6. According to claim 2a method for operating a wireless charging system, it is characterized in that the method comprises the steps of, The first transmitting unit also judges whether equipment to be charged exists in the charging area, and the method comprises the following steps: the excitation coil (1) is applied with a frequency of Wherein L D1 is the equivalent inductance of the first transmitting unit, and C D1 is the equivalent capacitance of the first transmitting unit; The second phase difference 2 of the following two parameters is compared: Parameter 3 is the voltage of the ac signal applied to the excitation coil (1); parameter 4, current of the first emission unit; when the value of the second phase difference is in the first threshold range or the second threshold range, judging that the equipment to be charged is in the charging area, or else, judging that the equipment to be charged is not in the charging area; Presetting a phase difference threshold value phi T , and dividing a first threshold range and a second threshold range: the first threshold range is [0 °, Φ T ]; The second threshold range is [ Φ T ', 360 ° ], where Φ T '=360°-Ф T .
  7. 7. The method of operating a wireless charging system according to any one of claims 4-6, wherein, The method for acquiring the preset phase difference threshold value phi T comprises the following steps: Ф T =[(t3-t1)/(t2-t1)]*360° Wherein t1 is the rising edge trigger time of the first period of the voltage of the alternating current signal loaded to the exciting coil (1); t2 is the rising edge trigger time of the second period of the voltage of the alternating current signal applied to the exciting coil (1); t3 is the rising edge trigger time of the first period of the total current of the circuit formed by connecting the first transmitting unit and the transmitting unit where the control switch (S) is closed each time in parallel.

Description

Working method of wireless charging system Technical Field The invention relates to the field of wireless charging, in particular to a working method of a wireless charging system. Background Wireless charging is a technology that can directly transmit electric energy without physical contact, and there is generally a certain position offset between the wireless charging transmitting coil and the receiving coil. When a transmitting coil and a receiving coil have larger deviation, the transmission power and efficiency of the wireless charging system are obviously reduced, and particularly when the deviation exceeds a certain range, even the situation that the wireless charging system cannot be charged occurs, which affects the experience of the wireless charging technology and the popularization of the technology, so that the improvement of the deviation range of the wireless charging is one of the key problems to be solved by the wireless charging technology. In addition, the existing wireless charging technology, especially for small-power products for charging mobile phones, has defects in the aspects of position judgment, metal foreign matter detection and the like of the products to be charged. The position judgment of the product to be charged is not carried out in low-power wireless charging products in the market, whether the device to be charged is placed or not is judged, then all the transmitting coils start to work, but the receiving coils are not necessarily positioned above the transmitting coils, so that the problems of low charging efficiency, energy waste and large heating value are caused. For metal foreign matter detection, low-power products are generally not configured, which has a large potential safety hazard for wireless charging. Disclosure of Invention The invention provides a working method of a wireless charging system. The device to be charged is supported to have a larger offset range, the corresponding transmitting coil can be selected to work, and foreign matters can be detected. The working method of the wireless charging system comprises the steps of placing equipment, judging the position of a coil, connecting each transmitting unit in sequence through a control switch, connecting the transmitting units in parallel with the first transmitting unit to form a circuit, always coupling an exciting coil with the first transmitting unit, and loading the exciting coil with the frequency ofThe method comprises the steps of judging whether a receiving coil of equipment to be charged is arranged above an accessed transmitting unit, if yes, taking a corresponding transmitting unit as a working transmitting unit and other non-working transmitting units, wherein L D2 is an equivalent inductance after each time of access to the transmitting unit, C D2 is an equivalent capacitance after each time of access to the transmitting unit, carrying out power judgment, counting the total working power of all the working transmitting units, if the charging power requirement of the equipment to be charged is met, starting wireless charging, otherwise, carrying out metal foreign matter detection, and carrying out metal foreign matter detection, wherein a first control switch of a first transmitting unit is kept to be closed, then a control switch of the non-working transmitting unit is sequentially connected, and the loading working frequency of an exciting coil is as followsTo determine whether the corresponding transmitting unit is misjudged as a non-working transmitting unit due to metal foreign matters, wherein L D3 is an equivalent inductance after the non-working unit is connected, and C D3 is an equivalent capacitance after the non-working unit is connected. Preferably, the first transmitting unit is in a charging central position, and when the device to be charged is placed in a charging area, the receiving coil and the first transmitting unit are always in a couplable state. Preferably, the first transmitting unit is coupled to the receiving coil and is further used for information transmission, and the transmitted information includes at least one of a charging request, a charging power requirement and a charging stop notification. Preferably, in the coil position judgment, the loading operating frequency isAfter the alternating current signals of the exciting coil, comparing a first phase difference of a parameter 1, a parameter 2, a total current of a circuit formed by connecting a first transmitting unit and the transmitting unit where a control switch is closed in parallel, wherein when the value of the first phase difference is in a first threshold range or a second threshold range, a receiving coil is arranged at the position where the corresponding transmitting unit is located, otherwise, the receiving coil is not arranged, a phase difference threshold value phi T is preset, the first threshold range and the second threshold range are divided, wherein the first threshold range is [0