An inductive power supply based on a non-closed magnetic core and a power supply method thereof

Abstract

The present invention provides an inductive power supply based on a non-closed magnetic core, including a magnetic energy collection module and an electric energy management circuit module. The magnetic energy collection module includes a non-closed magnetic core coil assembly and a resonant capacitor. The electric energy management circuit module includes an overcurrent and overvoltage protection circuit, a charge pump voltage doubling circuit, a voltage stabilizing circuit, a supercapacitor charging circuit, a supercapacitor and a supercapacitor discharge circuit connected in sequence. The charging circuit is connected to the voltage stabilizing circuit, and the discharge circuit is connected to the charge pump voltage doubling circuit through its switch tube; the voltage stabilizing circuit and the discharge circuit are connected to the load through a discharge diode, respectively. The power supply of the present invention adopts a magnetic energy collection module based on a non-closed magnetic core, which can be applied to cables of different voltage levels and sizes, is easy to install and disassemble, and reduces the power supply dead zone through the charge pump circuit and supercapacitor energy storage, reduces the design difficulty of the electric energy management circuit, and can provide stable power supply to the load when the current carrying capacity fluctuates in a wide range.

Description

Technical Field

[0001] The present invention belongs to the technical field of inductive power supply, and more specifically, relates to an inductive power supply with a non-closed magnetic core and a power supply method thereof. Background Art

[0002] In order to ensure the safe operation of power cables, the operating status of power cables requires real-time online monitoring by wireless sensor equipment, and the self-power supply problem of sensors is the core problem that restricts their large-scale application. Subsurface power cables are basically laid in corresponding cable trenches. Of course, some cables are directly buried in the soil. The cable lines are long and the distribution surface is relatively scattered, which is not easy to use low-voltage power supply. Such special working conditions have higher requirements for wireless sensor devices. High-voltage transmission lines are usually distributed in sparsely populated wilderness. The environment around the lines is full of strong electromagnetics. It is impossible to directly use transmission lines to power online monitoring sensor devices, nor can they have dedicated power supply lines like indoor equipment. Even if there are dedicated power supply lines, the different voltage levels will cause insulation and other problems.

[0003] By utilizing the changing magnetic fields near the cables, we can continuously provide usable energy to nearby wireless sensor devices and achieve energy self-sufficiency.

[0004] At present, CT power is commonly used to power sensor equipment. Generally, CT power is a special electromagnetic ring plus coil, which allows the current-carrying power cable to pass through the magnetic ring. When the power cable flows through the changing AC current carrying capacity, the changing AC voltage is induced at the coil port of the CT device, and the changing voltage is converted into a stable low-voltage DC through the power management circuit to power loads such as sensors. The power management circuit includes an AC side protection circuit, a rectifier and filter circuit, a DC side protection circuit, a DCDC voltage stabilization circuit, a battery charging circuit, a battery discharging circuit, and an energy discharge circuit. When the cable current carrying capacity is low, the battery circuit is used to power the load to reduce the power supply dead zone. When the cable current carrying capacity is high, the battery charging circuit is used to charge the battery. When the CT core is oversaturated, the protection circuit is used to protect it and discharge the excess energy.

[0005] The disadvantage of the existing CT power supply technology based on closed magnetic core is that its closed-loop magnetic core needs to be designed according to the cable size and is not easy to install and disassemble. When the cable current carrying capacity is large, the CT power supply induction magnetic core is easy to saturate, resulting in core heating and reduced power supply efficiency. The voltage distortion increases in the oversaturated state, which increases the requirements for the subsequent management circuit and complicates the design of the power management circuit.

[0006] The disadvantage of the existing CT power supply technology based on non-closed magnetic core is that due to the low output power, there are many power supply dead zones, and stable power supply to the load cannot be achieved. Summary of the invention

[0007] The object of the present invention is to provide an inductive power supply based on a non-closed magnetic core and a power supply method thereof, so as to reduce the power supply dead zone and realize stable power supply to the load.

[0008] In order to achieve the above-mentioned purpose, the present invention provides an inductive power supply based on a non-closed magnetic core, including a magnetic energy collection module and an electric energy management circuit module, the magnetic energy collection module includes a non-closed magnetic core coil assembly and a resonant capacitor, the electric energy management circuit module includes an overcurrent and overvoltage protection circuit, a charge pump voltage doubling circuit, a first voltage stabilizing circuit and a supercapacitor energy storage module connected in sequence, the supercapacitor energy storage module includes a supercapacitor charging circuit, a supercapacitor and a supercapacitor discharge circuit connected in sequence, the supercapacitor charging circuit is connected to the first voltage stabilizing circuit, and the supercapacitor discharge circuit is connected to the charge pump voltage doubling circuit through its fourth switch tube; the first voltage stabilizing circuit and the supercapacitor discharge circuit are connected to the load through a first discharge diode and a second discharge diode, respectively.

[0009] Preferably, the first voltage stabilizing circuit is configured to receive the voltage at the output end of the charge pump voltage doubler circuit, and convert the voltage at the output end of the charge pump voltage doubler circuit into a stable output DC power supply voltage when the voltage exceeds a stable power supply threshold of the voltage stabilizing circuit, and output it to the load;

[0010] The supercapacitor charging circuit is configured to charge the supercapacitor using the voltage at the output end of the first voltage stabilizing circuit when the voltage at the output end of the charge pump voltage doubling circuit is greater than the stable power supply threshold of the voltage stabilizing circuit and the voltage at both ends of the supercapacitor is less than the minimum charging cut-off voltage of the supercapacitor; otherwise, charging is stopped;

[0011] The supercapacitor discharge circuit is configured such that: when the voltage at the output end of the charge pump voltage doubling circuit is less than the stable power supply threshold of the voltage stabilizing circuit and the voltage across the supercapacitor is greater than or equal to the minimum charging cut-off voltage, the voltage across the supercapacitor is used to power the load through the LDO linear regulator of the supercapacitor discharge circuit; otherwise, the supercapacitor discharge circuit stops discharging.

[0012] Preferably, the supercapacitor charging circuit includes at least a first charging diode and a current limiting resistor connected to the first voltage stabilizing circuit, and the supercapacitor discharging circuit includes at least a fourth switch tube connected to the charge pump voltage multiplier circuit and an LDO linear regulator connected to the fourth switch tube through an enable pin, and the LDO linear regulator is connected to the supercapacitor through its IN pin.

[0013] Preferably, the supercapacitor charging circuit includes a first charging diode, a second switch tube and a current limiting resistor connected in sequence, the first charging diode is connected to the output end of the first voltage stabilizing circuit, the current limiting resistor is connected to one end of the supercapacitor, and the other end of the supercapacitor is grounded; the drain of the second switch tube is connected to the first charging diode, its source is grounded, and its gate is connected to the drain of the third switch tube and grounded through a fifth resistor; the source of the third switch tube is connected to the output end of the charge pump voltage doubler circuit, its gate is connected to the drain of the first switch tube through a sixth resistor, and is connected to the output end of the charge pump voltage doubler circuit through a seventh resistor; the source of the first switch tube is grounded, and its gate is connected to the output end of the hysteresis comparator; the output end of the hysteresis comparator is grounded through an eighth resistor, and is connected to the positive input end of the hysteresis comparator through a ninth resistor; the positive input end of the hysteresis comparator is connected to the power supply end of the hysteresis comparator, and is connected to the output end of the first voltage stabilizing circuit through a tenth resistor; the reverse input end of the hysteresis comparator is connected to the connection point of the current limiting resistor and the supercapacitor, and the ground end of the hysteresis comparator is grounded.

[0014] Preferably, the LDO linear regulator has an IN pin, an EN pin, a GND pin, an FB pin and an OUT pin; the gate of the fourth switch tube is connected to the output end of the charge pump voltage doubler circuit and is connected to the drain of the fourth switch tube through a twelfth resistor, the drain of the fourth switch tube is connected to the EN pin of the LDO linear regulator, and the source of the fourth switch tube is grounded; the ungrounded end of the supercapacitor is connected to the IN pin of the LDO linear regulator; the OUT pin of the LDO linear regulator is grounded through the twelfth capacitor and is grounded through a thirteenth resistor and a fourteenth resistor connected in series with each other; the FB pin of the LDO linear regulator is connected to the connection point of the thirteenth resistor and the fourteenth resistor; the IN pin of the LDO linear regulator is also grounded through the thirteenth capacitor.

[0015] Preferably, the overcurrent and overvoltage protection circuit is composed of a smoothing inductor connected in series with one output end of the magnetic energy collection module and a transient suppression diode connected in parallel to two output ends of the magnetic energy collection module, the two ends of the transient suppression diode are the two output ends of the overcurrent and overvoltage protection circuit, and one of the output ends of the overcurrent and overvoltage protection circuit is grounded.

[0016] Preferably, the charge pump voltage doubling circuit includes a first Schottky diode, a second Schottky diode, a third Schottky diode, a fourth Schottky diode, a fifth Schottky diode and a fifth voltage doubling capacitor which are sequentially connected between the two output ends of the overcurrent and overvoltage protection circuit according to the current flow direction, a first voltage doubling capacitor having one end connected to the cathode of the first Schottky diode and the other end connected to ground, a second voltage doubling capacitor having one end connected to the anode of the first Schottky diode and the other end connected to the cathode of the second Schottky diode, a third voltage doubling capacitor having one end connected to the cathode of the third Schottky diode and the other end connected to ground, and a fourth voltage doubling capacitor having one end connected to the anode of the third Schottky diode and the other end connected to the cathode of the second Schottky diode.

[0017] Preferably, the first voltage stabilizing circuit is a DCDC voltage stabilizing circuit, which is composed of a voltage stabilizer and its peripheral circuits.

[0018] Preferably, the output end of the charge pump voltage doubling circuit is directly connected to the VCC pin of the voltage regulator, connected to the SWC pin, Ipk pin and DRV pin of the voltage regulator through the second resistor, and grounded through the eighth capacitor; the Ct pin of the voltage regulator is grounded through the ninth capacitor, and the GND pin of the voltage regulator is directly grounded; the IN pin of the voltage regulator is grounded through the first feedback resistor, and connected to the SWE pin of the voltage regulator through the second feedback resistor and the second inductor; the SWE pin of the voltage regulator is also connected to the cathode of the tenth diode, and the anode of the tenth diode is grounded; the connection point of the second feedback resistor and the second inductor is grounded through the tenth capacitor, and connected to the third inductor, the third inductor is grounded through the eleventh capacitor, and connected to the load through the first discharge diode.

[0019] On the other hand, the present invention provides a power supply method based on an inductive power supply of a non-closed magnetic core, comprising:

[0020] S1: Build an inductive power supply according to the non-closed magnetic core described above and turn it on;

[0021] S2: Sending AC induced voltage to the charge pump voltage doubling circuit through the magnetic energy collection module;

[0022] S3: using the first voltage stabilizing circuit to receive the voltage at the output end of the charge pump voltage doubler circuit, and when the voltage at the output end of the charge pump voltage doubler circuit exceeds the stable power supply threshold of the voltage stabilizing circuit, stably outputting the DC power supply voltage to the load; otherwise, the first voltage stabilizing circuit stops supplying power;

[0023] S4: using the supercapacitor charging circuit, when the voltage at the output end of the charge pump voltage doubling circuit is greater than the stable power supply threshold of the voltage stabilizing circuit and the voltage at both ends of the supercapacitor is less than the minimum charging cut-off voltage of the supercapacitor, using the output voltage of the first voltage stabilizing circuit to charge the supercapacitor; otherwise, the supercapacitor charging circuit stops charging;

[0024] S5: Using the supercapacitor discharge circuit, when the voltage at the output end of the charge pump voltage doubler circuit is less than the stable power supply threshold of the voltage stabilization circuit and the voltage across the supercapacitor is greater than or equal to the minimum charging cut-off voltage, the voltage across the supercapacitor is used to power the load through the LDO linear regulator of the supercapacitor discharge circuit; otherwise, the supercapacitor discharge circuit stops discharging.

[0025] The inductive power supply based on a non-closed magnetic core of the present invention adopts a magnetic energy collection module based on a non-closed magnetic core. The magnetic core is not easy to saturate and is easy to install and disassemble. The power supply dead zone is reduced by designing a charge pump circuit and supercapacitor energy storage, thereby reducing the design difficulty of the power management circuit, and can provide stable power supply to the load when the current carrying capacity fluctuates in a wide range. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural block diagram of the inductive power supply based on a non-closed magnetic core of the present invention.

[0027] Figure 2 It is a circuit schematic diagram of a charge pump voltage doubling circuit and a first voltage stabilizing circuit of an inductive power supply based on a non-closed magnetic core according to an embodiment of the present invention.

[0028] Figure 3 The present invention is a circuit schematic diagram of a supercapacitor charging circuit based on an inductive power supply with a non-closed magnetic core according to an embodiment of the present invention.

[0029] Figure 4 The present invention is a circuit schematic diagram of a supercapacitor discharge circuit based on an inductive power supply with a non-closed magnetic core according to an embodiment of the present invention. DETAILED DESCRIPTION

[0030] The preferred embodiments of the present invention are given below in conjunction with the accompanying drawings and described in detail.

[0031] The present invention provides an inductive power supply based on a non-closed magnetic core, which is used to stably supply power to a load (such as a low-power sensor with a resistance of 1 kΩ). Figure 1 As shown, the inductive power supply based on the non-closed magnetic core includes a magnetic energy collection module 10 and a power management circuit module 20.

[0032] The magnetic energy collection module 10 includes a non-closed magnetic core coil assembly 11 and a resonant capacitor C1. The secondary side of the non-closed magnetic core coil 11 has two output ends, one of which is connected in series with the resonant capacitor C1 and connected to an input end of the power management circuit module 20 through the resonant capacitor C1, and the other output end is directly connected to the other input end of the power management circuit module 20.

[0033] The power management circuit module 20 includes an overcurrent and overvoltage protection circuit 21, a charge pump voltage doubling circuit 22, a first voltage stabilizing circuit 23 and a supercapacitor energy storage module 24 connected in sequence. The supercapacitor energy storage module 24 includes a supercapacitor charging circuit 241, a supercapacitor C2 and a supercapacitor discharging circuit 242 connected in sequence. The supercapacitor charging circuit 241 is connected to the first voltage stabilizing circuit 23, and the supercapacitor discharging circuit 242 is connected to the charge pump voltage doubling circuit 22 through its fourth switch tube Q4; the first voltage stabilizing circuit 23 and the supercapacitor discharging circuit 242 are respectively connected to a load (such as a load of a low power consumption sensor) through a first discharge diode D1 and a second discharge diode D2.

[0034] Specifically, the overcurrent and overvoltage protection circuit 21 has two input ends and two output ends, the input end of which is the two input ends of the power management circuit module 20 and is connected to the two output ends of the magnetic energy collection module 10, and the output end of which is connected to the charge pump voltage doubler circuit 22. The charge pump voltage doubler circuit 22 has an input end and an output end, the input end of the charge pump voltage doubler circuit 22 is connected to the output end of the overcurrent and overvoltage protection circuit 21, the output end of the charge pump voltage doubler circuit 22 is connected to the first voltage stabilizing circuit 23, and is connected to the supercapacitor energy storage module 24 through the fourth switch tube Q4.

[0035] The first voltage stabilizing circuit 23 is a DCDC voltage stabilizing circuit, the input end of the first voltage stabilizing circuit 23 is connected to the output end of the charge pump voltage doubling circuit 22 , the output end is connected to the load through the first discharge diode D1 , and the output end is connected to the supercapacitor charging circuit 241 .

[0036] The supercapacitor charging circuit 241 at least includes a first charging diode D3 and a current limiting resistor R1 connected to the first voltage stabilizing circuit 23. The supercapacitor discharging circuit 242 at least includes a fourth switch tube Q4 connected to the charge pump voltage doubling circuit 22 and an LDO linear regulator connected to the fourth switch tube Q4 through an EN pin (i.e., an enable pin), and the LDO linear regulator is also connected to the supercapacitor C2 through its IN pin. Thus, the supercapacitor C2 is used to enable the LDO linear regulator to work and supply power to the load through the LDO linear regulator when the output of the first voltage stabilizing circuit 23 is insufficient.

[0037] In this embodiment, the non-closed magnetic core coil assembly 11 is composed of 14 thin cylindrical magnetic cores and a coil sleeved on the thin cylindrical magnetic core, and at least a part of the thin cylindrical magnetic core can be pulled relative to the coil to increase the output power. The resonant capacitor C1 is connected in series to one of the output ends of the non-closed magnetic core coil assembly 11 to match the maximum output power, and the other output end of the non-closed magnetic core coil assembly 11 is grounded. The non-closed magnetic core coil assembly 11 can be clamped on the surface of the power cable. When the cable current carrying capacity is 100A, the magnetic energy collection module 10 with a load of 1kΩ can collect 10mW of power. Therefore, the inductive power supply based on the non-closed magnetic core of the present invention adopts a right-angled pullable magnetic core, which is smaller in volume and mass than the CT magnetic ring, has good output power and power density, and the magnetic core is not easy to saturate, and can be applied to cables of different voltage levels and sizes. That is, it includes other forms of non-closed magnetic cores and coils.

[0038] like Figure 2 As shown, the overcurrent and overvoltage protection circuit 21 is composed of a smoothing inductor L1 connected in series with one output end of the magnetic energy collection module 10 and a transient suppression diode D4 connected in parallel to the two output ends of the magnetic energy collection module 10. The two ends of the transient suppression diode D4 are the two output ends of the overcurrent and overvoltage protection circuit 21, and one of the output ends of the overcurrent and overvoltage protection circuit 21 is grounded. Therefore, when the port induced voltage between the two output ends of the magnetic energy collection device 10 exceeds the specified value, the transient suppression diode D4 is turned on, which has a protective effect on the back-end circuit at the output end of the overcurrent and overvoltage protection circuit 21. The transient suppression diode D4 also limits the AC induced voltage that exceeds the clamping voltage, and plays a pre-stabilization role. The smoothing inductor L1 has both smoothing and current limiting functions, and the current limiting effect is obvious and fast. In this embodiment, the output signal of the magnetic energy collection module 10 is an AC signal V1 with a frequency of 50 Hz and a voltage root mean square of 50 Vrms, the inductance of the smoothing inductor L1 is 0.25 mH, and the model of the transient suppression diode D4 is P4KE10CA-E3 / 54.

[0039] The charge pump voltage doubling circuit 22 is connected to the two output ends of the overcurrent and overvoltage protection circuit 21. The charge pump voltage doubling circuit 22 is composed of five voltage doubling capacitors C3, C4, C5, C6, C7 and five Schottky diodes D5, D6, D7, D8, D9. Specifically, the charge pump voltage doubling circuit 22 includes a first Schottky diode D5, a second Schottky diode D6, a third Schottky diode D7, a fourth Schottky diode D8, a fifth Schottky diode D9 and a fifth voltage doubling capacitor C7, which are sequentially connected between the two output ends of the overcurrent and overvoltage protection circuit 21 according to the current flow direction. In addition, the charge pump voltage doubling circuit 22 further includes a first voltage doubling capacitor C3 having one end connected to the cathode of the first Schottky diode D5 and the other end grounded, a second voltage doubling capacitor C4 having one end connected to the anode of the first Schottky diode D5 and the other end connected to the cathode of the second Schottky diode D6, a third voltage doubling capacitor C5 having one end connected to the cathode of the third Schottky diode D7 and the other end grounded, and a fourth voltage doubling capacitor C6 having one end connected to the anode of the third Schottky diode D7 and the other end connected to the cathode of the second Schottky diode D6. The cathode of the fifth Schottky diode D9 is the output end of the charge pump voltage doubling circuit 22. In this embodiment, the capacitance of the five voltage doubling capacitors C3, C4, C5, C6, and C7 are all 1000pF, and the models of the five Schottky diodes D5, D6, D7, D8, and D9 are all 1BH62.

[0040] Therefore, assuming that at the input end of the charge pump voltage circuit 22, the effective value of the induced voltage after smoothing and current limiting is U, the first voltage doubling capacitor C3 is charged through the first Schottky diode D5, the second voltage doubling capacitor C4 is charged through the first voltage doubling capacitor C3 and the second Schottky diode D6, the third voltage doubling capacitor C5 is charged through the second voltage doubling capacitor C4 and the third Schottky diode D7, the second voltage doubling capacitor C4 and the fourth voltage doubling capacitor C6 are charged through the third voltage doubling capacitor C5 and the fourth Schottky diode D8, and the fifth voltage doubling capacitor C7 is charged through the second voltage doubling capacitor C4, the fourth voltage doubling capacitor C6 and the fifth Schottky diode D9, and the voltage at the output end of the charge pump voltage circuit 22 finally obtained is 5U. Then the next level circuit is powered by the fifth voltage doubling capacitor C7 to achieve the goal of rectifier voltage doubling. Therefore, if the induced voltage is greater than the dead zone voltage of the Schottky diodes D5, D6, D7, D8, and D9, the circuit can operate normally. The charge pump voltage doubling circuit 22 is configured to double the lower induced voltage and provide it to subsequent circuits.

[0041] The first voltage stabilizing circuit 23 is connected to the output end of the charge pump voltage doubling circuit 22 (i.e., the negative electrode of the fifth Schottky diode D9). The first voltage stabilizing circuit 23 is a DCDC voltage stabilizing circuit, which is composed of a voltage stabilizer U1 and its peripheral circuits. In this embodiment, the voltage stabilizer U1 is of the model MC34063ADG, which has 8 pins, namely, SWC pin (i.e., switch tube collector pin), SWE pin (i.e., switch tube emitter pin), Ct pin (i.e., timing capacitor pin), GND pin, IN pin (i.e., comparator reverse input pin), VCC pin, Ipk pin and DRV pin (i.e., driver tube collector pin).

[0042] like Figure 2 and Figure 3 As shown, the peripheral circuit of the first voltage stabilizing circuit 23 includes the following components: the output terminal VCC of the charge pump voltage doubling circuit 22 is directly connected to the VCC pin of the voltage regulator U1, connected to the SWC pin, Ipk pin and DRV pin of the voltage regulator U1 through the second resistor R2, and grounded through the eighth capacitor C8. The Ct pin of the voltage regulator U1 is grounded through the ninth capacitor C9, and the GND pin of the voltage regulator U1 is directly grounded. The IN pin of the voltage regulator U1 is grounded through the first feedback resistor R3, and connected to the SWE pin of the voltage regulator U1 through the second feedback resistor R4 and the second inductor L2. The SWE pin of the voltage regulator U1 is also connected to the cathode of the tenth diode D10, and the anode of the tenth diode D10 is grounded. The connection point between the second feedback resistor R4 and the second inductor L2 is grounded through the tenth capacitor C10, and is connected to the third inductor L3, the third inductor L3 is grounded through the eleventh capacitor C11, and is connected to the load through the first discharge diode D1.

[0043] In this embodiment, the resistance of the second resistor R2 is 0.33Ω, the capacitance of the eighth capacitor C8 is 100μF, the capacitance of the ninth capacitor C9 is 470pF, the resistance of the first feedback resistor R3 is 1kΩ, the resistance of the second feedback resistor R4 is 1.64kΩ, and the inductance of the second inductor L2 is 220μH. The tenth diode D10 is a Schottky diode, and its model is 1N5819G. The capacitance of the tenth capacitor C10 is 470μF. The inductance of the third inductor L3 is 1μH. The capacitance of the eleventh capacitor C11 is 100μF.

[0044] The first voltage stabilizing circuit 23 is configured to receive the voltage at the output end of the charge pump voltage doubling circuit 22, and when the voltage at the output end of the charge pump voltage doubling circuit 22 exceeds the stable power supply threshold value of the voltage stabilizing circuit (which is 5V), the voltage is converted from a wide range of DC to a stable output DC power supply voltage, and then output to the load (such as a wireless sensor device) for use. The voltage value of the DC power supply voltage is 3.3V.

[0045] The voltage range of the input end of the first voltage stabilizing circuit 23 is 2.5-40V, and the voltage of the output end of the first voltage stabilizing circuit 23 is related to the ratio of the size of the peripheral second feedback resistor R4 and the first feedback resistor R3. 1.25V is the reference voltage and remains unchanged. If the resistance values ​​of the two resistors remain unchanged, the voltage of the output end of the first voltage stabilizing circuit 23 is +3.3V.

[0046] like Figure 4 As shown, the supercapacitor charging circuit 241 is connected to the output end VDC1 of the first voltage stabilizing circuit 23, and the supercapacitor charging circuit 241 includes the first, second, and third switch tubes Q1, Q2, Q3, a hysteresis comparator U3A, a first charging diode D3, and a current limiting resistor R1. Specifically, the supercapacitor charging circuit 241 includes a first charging diode D3, an eleventh resistor R11, a second switch tube Q2, and a current limiting resistor R1 connected in sequence, the first charging diode D3 is connected to the output end of the first voltage stabilizing circuit 23, the current limiting resistor R1 is connected to one end of the supercapacitor C2, and the other end of the supercapacitor C2 is grounded. Among them, the drain of the second switch tube Q2 is connected to the first charging diode D3, its source is grounded, and its gate is connected to the drain of the third switch tube Q3 and is grounded through the fifth resistor R5. The source of the third switch tube Q3 is connected to the output terminal VCC of the charge pump voltage doubler circuit 22, and the gate thereof is connected to the drain of the first switch tube Q1 through the sixth resistor R6, and is connected to the output terminal VCC of the charge pump voltage doubler circuit 22 through the seventh resistor R7. The source of the first switch tube Q1 is grounded, and the gate thereof is connected to the output terminal of the hysteresis comparator U3A. The output terminal of the hysteresis comparator U3A is grounded through the eighth resistor R8, and is connected to the positive input terminal of the hysteresis comparator U3A through the ninth resistor R9; the positive input terminal of the hysteresis comparator U3A is connected to the power supply terminal of the hysteresis comparator U3A, and is connected to the output terminal VDC1 of the first voltage stabilizing circuit 23 through the tenth resistor R10; the reverse input terminal of the hysteresis comparator U3A is connected to the connection point of the current limiting resistor R1 and the super capacitor C2, and the ground terminal of the hysteresis comparator U3A is grounded.

[0047] Among them, the first switch tube Q1 and the second switch tube Q2 are N-channel MOSFETs, and their model is NTR4003NT1G, and the third switch tube Q3 is a P-channel MOSFET, and its model is NTR1P02LT1G. The first charging diode D3 is a Schottky diode with a model of 1BH62, the resistance of the current limiting resistor R1 is 60Ω, the resistance of the fifth resistor R5 is 10kΩ, the resistance of the sixth resistor R6 is 15kΩ, and the resistance of the seventh resistor R7 is 2.88kΩ. The model of the hysteresis comparator U3A is LM339N. The resistance of the eighth resistor R8 is 10kΩ, the resistance of the ninth resistor R9 is 40kΩ, and the resistance of the tenth resistor R10 is 10kΩ. The resistance of the eleventh resistor R11 is 100Ω, which also plays the role of charging current limiting.

[0048] Therefore, through the combination of the first, second and third switch tubes Q1, Q2 and Q3, the voltage at the output terminal VCC of the charge pump voltage doubler circuit 22 can be used as a control signal for charging the super capacitor C2. When the voltage at the output terminal VCC of the charge pump voltage doubler circuit 22 is greater than the stable power supply threshold of the voltage stabilizing circuit and the voltage across the super capacitor C2 is less than the minimum charging cut-off voltage of the super capacitor C2, the second switch tube Q2 is turned on to charge the super capacitor C2, otherwise, the charging is stopped.

[0049] That is to say, the supercapacitor charging circuit 241 is configured as follows: when the voltage at the output terminal VCC of the charge pump voltage doubling circuit 22 is greater than the stable power supply threshold of the voltage stabilizing circuit and the voltage across the supercapacitor C2 is less than the minimum charging cut-off voltage of the supercapacitor C2, the supercapacitor C2 is charged using the voltage at the output terminal of the first voltage stabilizing circuit 23; otherwise, charging is stopped.

[0050] In order to ensure that the supercapacitor can be stably charged, the voltage stabilization circuit power supply threshold is set to 5V, that is, when the voltage at the VCC terminal (that is, the voltage at the input terminal of the first voltage stabilization circuit 23) is greater than 5V, it is used as a supercapacitor charging control signal, and the second switch tube Q2 is turned on to start the charging mode. The first voltage stabilization circuit 23 acts as a DC source to charge the supercapacitor C2 through the current limiting resistor R1 and the first charging diode D3. The output voltage V of the first voltage stabilization circuit 23 out The voltage drop of the first charging diode D3 is generally 0.2-0.3V. When selecting the supercapacitor C2, the rated voltage is selected to be 2.7V to control the cost requirements and facilitate the selection. Then the maximum charge cut-off voltage of the supercapacitor C2 can be 3.0V, and the minimum charge cut-off voltage of the supercapacitor C2 is 2.4V. If the voltage across the supercapacitor C2 is less than the minimum charge cut-off voltage, the hysteresis comparator outputs a high level to turn on Q1. The condition for Q3 to turn on is to adjust R7 and R6 at 3.3V to set the gate voltage V of Q3. GGreater than the threshold voltage of 0.8V, when the voltage regulator module input voltage V in =5V, then in this case, the control voltage of Q2 is V in -V out >1V, so Q2 is turned on, and the super capacitor enters the charging state. So the three MOSFETs are all in the on state to realize charging. The whole charging logic is: when the voltage of the output terminal VCC of the charge pump voltage doubler circuit 22 is less than 5V, and the voltage of the output terminal VDC1 of the first voltage stabilizing circuit 23 is less than 2.4V, Q1, Q2, and Q3 are all in the off state, and the super capacitor C2 stops charging. Only when the voltage of the output terminal VCC of the charge pump voltage doubler circuit 22 is greater than 5V, and the voltage at both ends of the super capacitor C2 is less than the minimum charging cut-off voltage 2.4V, Q1, Q2, and Q3 are all in the on state, and the super capacitor C2 starts charging. In other cases, the super capacitor C2 stops charging. For example, when the voltage of the output terminal VCC of the charge pump voltage doubler circuit 22 is less than 5V, and the voltage at both ends of the super capacitor C2 is greater than 2.4V, Q1, Q2, and Q3 are all in the off state, and the super capacitor stops charging. When the voltage at the output terminal VCC of the charge pump voltage doubler circuit 22 is greater than 5V and the voltage across the super capacitor C2 is greater than 2.4V, Q1, Q2, and Q3 are all in the off state, and the super capacitor C2 stops charging.

[0051] like Figure 4As shown, the input end of the supercapacitor discharge circuit 242 is connected to the supercapacitor C2, and is connected to the output end of the charge pump voltage doubler circuit 22 through its fourth switch tube Q4. The supercapacitor discharge circuit 242 includes a fourth switch tube Q4, an LDO linear regulator U2 and its peripheral circuits. Specifically, the LDO linear regulator U2 has an IN pin, an EN pin (i.e., an enable pin), a GND pin, an FB pin (i.e., a feedback pin) and an OUT pin. The gate of the fourth switch tube Q4 is connected to the output end VCC of the charge pump voltage doubler circuit 22 and is connected to the drain of the fourth switch tube Q4 through the twelfth resistor R12. The drain of the fourth switch tube Q4 is connected to the EN pin of the LDO linear regulator U2, and the source of the fourth switch tube Q4 is grounded. The ungrounded end of the supercapacitor C2 is connected to the IN pin of the LDO linear regulator U2. The supercapacitor C2 is made of a first supercapacitor C21 and a second supercapacitor C22 connected in parallel. C21 and C22 are both common supercapacitors with a rated voltage of 2.7V. The voltage IC across the supercapacitor C2 can reach 3.0V. During the design process, the present invention uses two supercapacitors in parallel through a boost chip to obtain an output power supply voltage of 3.3V, and its energy is higher than the energy output by two supercapacitors in series through a buck chip. The OUT pin of the LDO linear regulator U2 is grounded through the twelfth capacitor C12, and is grounded through the thirteenth resistor R13 and the fourteenth resistor R14 connected in series; the FB pin of the LDO linear regulator U2 is connected to the connection point of the thirteenth resistor R13 and the fourteenth resistor R14. The IN pin of the LDO linear regulator U2 is also grounded through the thirteenth capacitor C13.

[0052] The fourth switch tube Q4 is an N-MOSFET, and its model is NTR4003NT1G. The model of the LDO linear regulator U2 is TPS71701DCKR, the resistance of the twelfth resistor R12 is 60Ω, the capacitance of the twelfth capacitor C12 is 1μF, and the capacitance of the third equivalent capacitor C23 of the super capacitor C2 is the same as the capacitance of the twelfth capacitor C12, which is also 1μF. The resistance of the thirteenth resistor R13 is 1.02kΩ, the resistance of the fourteenth resistor R14 is 324kΩ, and the capacitance of the thirteenth capacitor C13 is 1μF. The second discharge diode D2 is a Schottky diode, and its model is 1BH62.

[0053] The operating input voltage range of the LDO linear regulator U2 is 0.9V to 5.5V, and its energy-saving mode can improve the working efficiency under low output power conditions. The EN pin is connected to the drain of the fourth switch tube Q4, and the gate is connected to the output terminal VCC of the charge pump voltage doubler circuit 22, so that when the voltage of the output terminal VCC of the charge pump voltage doubler circuit 22 is less than 5.0V and the voltage across the super capacitor C2 is greater than 2.4V, the LDO linear regulator U2 is started to supply power to the rear-end load.

[0054] That is to say, the supercapacitor discharge circuit 242 is configured as follows: when the voltage at the output terminal VCC of the charge pump voltage doubler circuit 22 is less than the stable power supply threshold of the voltage stabilization circuit (whose value is 5V) and the voltage across the supercapacitor C2 is greater than or equal to the minimum charging cut-off voltage (whose value is 2.4V), the voltage across the supercapacitor C2 is used to power the load through the LDO linear regulator U2 of the supercapacitor discharge circuit 242; otherwise, the supercapacitor discharge circuit 242 stops discharging.

[0055] Based on the non-closed magnetic core inductive power supply described above, the power supply method based on the non-closed magnetic core inductive power supply is implemented, and the steps are as follows:

[0056] Step S1: Build the inductive power supply of the non-closed magnetic core described above and connect it;

[0057] Step S2: sending the AC induced voltage to the charge pump voltage doubling circuit 22 through the magnetic energy collection module 10;

[0058] Step S3: using the first voltage stabilizing circuit 23 to receive the voltage at the output end of the charge pump voltage doubler circuit 22, and when the voltage at the output end of the charge pump voltage doubler circuit 22 exceeds the voltage stabilizing circuit power supply threshold (the value of which is 5V), stably outputting the DC power supply voltage to the load; otherwise, the first voltage stabilizing circuit 23 stops supplying power;

[0059] Step S4: using the supercapacitor charging circuit 241, when the voltage at the output end VCC of the charge pump voltage doubling circuit 22 is greater than the stable power supply threshold of the voltage stabilizing circuit and the voltage across the supercapacitor C2 is less than the minimum charging cut-off voltage of the supercapacitor C2, the supercapacitor C2 is charged using the output voltage of the first voltage stabilizing circuit 23; otherwise, the supercapacitor charging circuit 241 stops charging;

[0060] Step S5: Using the supercapacitor discharge circuit 242, when the voltage at the output terminal VCC of the charge pump voltage doubler circuit 22 is less than the stable power supply threshold of the voltage stabilization circuit (whose value is 5V) and the voltage across the supercapacitor C2 is greater than or equal to the minimum charging cut-off voltage (whose value is 2.4V), the voltage across the supercapacitor C2 is used to power the load through the LDO linear regulator U2 of the supercapacitor discharge circuit 242; otherwise, the supercapacitor discharge circuit 242 stops discharging.

[0061] Specifically, even if the voltage at the output terminal VCC of the charge pump voltage doubler circuit 22 is lower than the stable power supply threshold of the voltage stabilization circuit, but the voltage across the super capacitor C2 is lower than the minimum charging cut-off voltage, the super capacitor enters the waiting state.

[0062] The present invention controls the enable pin of the LDO linear regulator U2 through the fourth switch tube Q4 and R12 of the supercapacitor discharge circuit 242. When the output voltage of the charge pump voltage doubler circuit is greater than 5V, the enable pin inputs a low level, the LDO linear regulator U2 stops supplying power, and is powered by the first voltage stabilizing circuit. When the output voltage of the charge pump voltage doubler circuit is less than 5V, the enable pin inputs a high level, and when the voltage across the supercapacitor is less than 2.4V, the LDO linear regulator U2 stops supplying power. When the voltage across the supercapacitor is greater than or equal to 2.4V, the LDO linear regulator U2 starts supplying power.

[0063] The above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. The above embodiment of the present invention can also be modified in various ways. That is, all simple, equivalent changes and modifications made according to the claims and the description of the present invention fall within the scope of protection of the claims of the present invention. The contents not described in detail in the present invention are all conventional technical contents.

Claims

1. An inductive power supply based on a non-closed magnetic core, characterized in that: It includes a magnetic energy collection module and an electric energy management circuit module, the magnetic energy collection module includes a non-closed magnetic core coil component and a resonant capacitor, the electric energy management circuit module includes an overcurrent and overvoltage protection circuit, a charge pump voltage doubling circuit, a first voltage stabilizing circuit and a supercapacitor energy storage module connected in sequence, the supercapacitor energy storage module includes a supercapacitor charging circuit, a supercapacitor and a supercapacitor discharge circuit connected in sequence, the supercapacitor charging circuit is connected to the first voltage stabilizing circuit, and the supercapacitor discharge circuit is connected to the charge pump voltage doubling circuit through its fourth switch tube; the first voltage stabilizing circuit and the supercapacitor discharge circuit are connected to the load through a first discharge diode and a second discharge diode respectively; The first voltage stabilizing circuit is configured to receive the voltage at the output end of the charge pump voltage doubler circuit, and convert the voltage at the output end of the charge pump voltage doubler circuit into a stable output DC power supply voltage when the voltage exceeds a stable power supply threshold of the voltage stabilizing circuit, and output it to the load; The supercapacitor charging circuit is configured to charge the supercapacitor using the voltage at the output end of the first voltage stabilizing circuit when the voltage at the output end of the charge pump voltage doubling circuit is greater than the stable power supply threshold of the voltage stabilizing circuit and the voltage at both ends of the supercapacitor is less than the minimum charging cut-off voltage of the supercapacitor; otherwise, charging is stopped; The supercapacitor discharge circuit is configured to: when the voltage at the output end of the charge pump voltage multiplier circuit is less than the stable power supply threshold of the voltage stabilization circuit and the voltage at both ends of the supercapacitor is greater than or equal to the minimum charging cut-off voltage, the voltage at both ends of the supercapacitor is used to supply power to the load through the LDO linear regulator of the supercapacitor discharge circuit; otherwise, the supercapacitor discharge circuit stops discharging; The overcurrent and overvoltage protection circuit is composed of a smoothing inductor connected in series with one output end of the magnetic energy collection module and a transient suppression diode connected in parallel with two output ends of the magnetic energy collection module, the two ends of the transient suppression diode are the two output ends of the overcurrent and overvoltage protection circuit, and one of the output ends of the overcurrent and overvoltage protection circuit is grounded; The charge pump voltage doubling circuit includes a first Schottky diode, a second Schottky diode, a third Schottky diode, a fourth Schottky diode, a fifth Schottky diode and a fifth voltage doubling capacitor which are sequentially connected between the two output ends of the overcurrent and overvoltage protection circuit according to the current flow direction, a first voltage doubling capacitor with one end connected to the cathode of the first Schottky diode and the other end connected to ground, a second voltage doubling capacitor with one end connected to the anode of the first Schottky diode and the other end connected to the cathode of the second Schottky diode, a third voltage doubling capacitor with one end connected to the cathode of the third Schottky diode and the other end connected to ground, and a fourth voltage doubling capacitor with one end connected to the anode of the third Schottky diode and the other end connected to the cathode of the second Schottky diode.

2. The inductive power supply based on a non-closed magnetic core according to claim 1 is characterized in that: The supercapacitor charging circuit at least includes a first charging diode and a current limiting resistor connected to the first voltage stabilizing circuit, and the supercapacitor discharging circuit at least includes a fourth switch tube connected to the charge pump voltage multiplier circuit and an LDO linear regulator connected to the fourth switch tube through an enable pin, and the LDO linear regulator is connected to the supercapacitor through its IN pin.

3. The inductive power supply based on a non-closed magnetic core according to claim 2 is characterized in that: The supercapacitor charging circuit comprises a first charging diode, a second switch tube and a current limiting resistor connected in sequence, wherein the first charging diode is connected to the output end of the first voltage stabilizing circuit, the current limiting resistor is connected to one end of the supercapacitor, and the other end of the supercapacitor is grounded; the drain of the second switch tube is connected to the first charging diode, the source thereof is grounded, the gate thereof is connected to the drain of the third switch tube and is grounded through a fifth resistor; the source of the third switch tube is connected to the output end of the charge pump voltage doubling circuit, the gate thereof is connected to the drain of the first switch tube through a sixth resistor, and is connected to the output end of the charge pump voltage doubling circuit through a seventh resistor; The source of the first switch tube is grounded, and the gate thereof is connected to the output end of the hysteresis comparator; the output end of the hysteresis comparator is grounded through an eighth resistor, and is connected to the positive input end of the hysteresis comparator through a ninth resistor; the positive input end of the hysteresis comparator is connected to the power supply end of the hysteresis comparator, and is connected to the output end of the first voltage stabilizing circuit through a tenth resistor; the reverse input end of the hysteresis comparator is connected to the connection point of the current limiting resistor and the super capacitor, and the ground end of the hysteresis comparator is grounded.

4. The inductive power supply based on a non-closed magnetic core according to claim 2 is characterized in that: The LDO linear regulator has an IN pin, an EN pin, a GND pin, a FB pin and an OUT pin; the gate of the fourth switch tube is connected to the output end of the charge pump voltage doubler circuit and is connected to the drain of the fourth switch tube through a twelfth resistor, the drain of the fourth switch tube is connected to the EN pin of the LDO linear regulator, and the source of the fourth switch tube is grounded; the ungrounded end of the super capacitor is connected to the IN pin of the LDO linear regulator; the OUT pin of the LDO linear regulator is grounded through the twelfth capacitor, and is grounded through the thirteenth resistor and the fourteenth resistor connected in series; the FB pin of the LDO linear regulator is connected to the connection point of the thirteenth resistor and the fourteenth resistor; the IN pin of the LDO linear regulator is also grounded through the thirteenth capacitor.

5. The inductive power supply based on a non-closed magnetic core according to claim 1, characterized in that: The first voltage stabilizing circuit is a DCDC voltage stabilizing circuit, which is composed of a voltage stabilizer and its peripheral circuits.

6. The inductive power supply based on a non-closed magnetic core according to claim 5, characterized in that: The output end of the charge pump voltage doubling circuit is directly connected to the VCC pin of the voltage regulator, connected to the SWC pin, Ipk pin and DRV pin of the voltage regulator through the second resistor, and grounded through the eighth capacitor; the Ct pin of the voltage regulator is grounded through the ninth capacitor, and the GND pin of the voltage regulator is directly grounded; the IN pin of the voltage regulator is grounded through the first feedback resistor, and connected to the SWE pin of the voltage regulator through the second feedback resistor and the second inductor; the SWE pin of the voltage regulator is also connected to the cathode of the tenth diode, and the anode of the tenth diode is grounded; the connection point between the second feedback resistor and the second inductor is grounded through the tenth capacitor, and connected to the third inductor, the third inductor is grounded through the eleventh capacitor, and connected to the load through the first discharge diode.

7. A power supply method based on an inductive power supply with a non-closed magnetic core, characterized in that: include: Step S1: constructing an inductive power supply of a non-closed magnetic core according to any one of claims 1 to 6 and connecting it; Step S2: sending the AC induced voltage to the charge pump voltage doubling circuit through the magnetic energy collection module; Step S3: using the first voltage stabilizing circuit to receive the voltage at the output end of the charge pump voltage doubler circuit, and when the voltage at the output end of the charge pump voltage doubler circuit exceeds the stable power supply threshold of the voltage stabilizing circuit, stably outputting the DC power supply voltage to the load; otherwise, the first voltage stabilizing circuit stops supplying power; Step S4: using the supercapacitor charging circuit, when the voltage at the output end of the charge pump voltage doubling circuit is greater than the stable power supply threshold of the voltage stabilizing circuit and the voltage across the supercapacitor is less than the minimum charging cut-off voltage of the supercapacitor, using the output voltage of the first voltage stabilizing circuit to charge the supercapacitor; otherwise, the supercapacitor charging circuit stops charging; Step S5: using the supercapacitor discharge circuit, when the voltage at the output end of the charge pump voltage doubler circuit is less than the stable power supply threshold of the voltage stabilization circuit and the voltage across the supercapacitor is greater than or equal to the minimum charging cut-off voltage, the voltage across the supercapacitor is used to power the load through the LDO linear regulator of the supercapacitor discharge circuit; otherwise, the supercapacitor discharge circuit stops discharging.

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