A farad capacitor battery for power distribution terminal

Abstract

The present invention relates to the field of capacitor batteries. A farad capacitor battery for a power distribution terminal comprises: a capacitor source group, a charging unit, and a discharging unit; one end of the capacitor source group is grounded, and the other end is connected to the discharging unit; the charging unit is connected to both ends of the capacitor source group; the capacitor source group has a plurality of farad capacitors connected in parallel; the charging unit comprises a charging protector and a current limiter; the current limiter, the charging protector, and the capacitor source group are connected in sequence; the discharging unit comprises a transformer and a discharge setter; the transformer is connected to the capacitor source group, and the discharge setter is connected to the transformer. The present invention provides a farad capacitor battery for a power distribution terminal, which uses a plurality of farad capacitors in parallel to work, and does not require a voltage equalization circuit. At this time, the working voltage of the farad capacitor is stable, which can ensure the long-term reliable operation of the farad capacitor.

Description

Technical Field

[0001] The present invention relates to the field of capacitor batteries, and in particular to a farad capacitor battery for a power distribution terminal. Background Art

[0002] At present, the voltage specification of supercapacitor monomer is DC2.7-3.0V. If it is used in a system with DC5V, DC12V and above power supply, the conventional solution is to use farad capacitors in series. The rated voltage of two or more capacitors in series matches the system voltage. Since the internal resistance of farad capacitors is different, voltage equalization resistors or voltage equalization circuits need to be added between farad capacitors. This application has the following disadvantages: a. If the voltage equalization circuit only uses resistor voltage equalization, the reliability is low. If chip control is used, the cost is high; b. When the voltage equalization circuit fails, the monomer capacitor may exceed its voltage rating, causing it to leak, corrode the circuit board, and damage the entire system; c. Waste charging energy and increase charging time. When the internal resistance difference of the supercapacitor is large, the voltage of the farad capacitor connected to the system ground may increase first during charging. Due to the existence of the voltage equalization circuit, if the voltage of this farad capacitor exceeds the set value, the charging current will be discharged directly to the system ground through the voltage equalization circuit, wasting charging energy and increasing charging time; d. The output of the farad capacitor module is direct output, and the voltage is unstable and decreases as the capacity decreases.

[0003] Since the rated voltage of conventional farad capacitors is around 2.7V, if the system voltage is higher than this voltage, the common design solution is to use farad capacitors in series. After the series connection, the rated voltage of the farad capacitor group is greater than the system voltage. However, due to the uneven internal resistance of the farad capacitor, resistor or circuit voltage balancing is required between the farad capacitors.

[0004] The patent document with the patent number ZL201410766990.X discloses a parallel farad capacitor charge and discharge protector, which includes: a farad capacitor, a power supply ground, an output protection diode, a power supply output terminal, an input protection resistor, a short circuit fuse, an input protection diode, and a power supply input terminal; multiple farad capacitors are connected in parallel in the circuit, and the output of each farad capacitor is connected to an output protection diode, and finally output to the power supply output terminal. At the input end of the farad capacitor, the input of each farad capacitor is connected to an input protection resistor, a short circuit fuse and an input protection diode, and finally all are connected to the power supply input terminal, and the negative poles of all farad capacitors are connected to the power supply ground. However, the structure provided is simple, and each capacitor is separately configured with a charge and discharge circuit, the charge and discharge process is relatively simple, and the number and size of the parallel capacitors cannot be adjusted dynamically, and the protection of the peripheral circuit and good power supply performance cannot be achieved.

[0005] Therefore, the existing Farad capacitor charging and discharging circuit still has shortcomings and needs to be improved and enhanced. Summary of the invention

[0006] In view of the above-mentioned deficiencies in the prior art, an object of the present invention is to provide a farad capacitor battery for a power distribution terminal, which can achieve stable discharge voltage of the farad capacitor battery without using a voltage equalization circuit, and has low charging loss and shortened charging time.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] A farad capacitor battery for a power distribution terminal, comprising: a capacitor source group, a charging unit, and a discharging unit; one end of the capacitor source group is grounded, and the other end is connected to the discharging unit; the charging unit is connected to both ends of the capacitor source group; the capacitor source group has a plurality of farad capacitors connected in parallel;

[0009] The charging unit includes a charging protector and a current limiter; the current limiter, the charging protector, and the capacitor source group are connected in sequence;

[0010] The discharge unit includes a voltage transformer and a discharge setter; the voltage transformer is connected to the capacitor source group, and the discharge setter is connected to the voltage transformer.

[0011] Preferably, the farad capacitor battery for the power distribution terminal, the charging protector comprises a voltage stabilizing diode and a PNP transistor; the voltage stabilizing diode has a cathode connected to the base of the PNP transistor, and a cathode connected to the grounded end of the capacitor source group;

[0012] The emitter of the PNP transistor is connected to the ungrounded end of the capacitor source group;

[0013] The current limiter is connected to the collector and the base of the PNP transistor respectively.

[0014] Preferably, the farad capacitor battery for the power distribution terminal, the current limiter includes a current limiting diode and two current limiting resistors; one end of the two current limiting resistors is respectively connected to the negative electrode of the current limiting diode, and the other end is respectively connected to the charging protector; the positive electrode of the current limiting diode is connected to the charging interface.

[0015] Preferably, in the farad capacitor battery for power distribution terminal, the transformer switch comprises a switch chip and a transformer inductor; the switch chip is connected to the ungrounded end of the capacitor source group through the transformer inductor.

[0016] Preferably, in the farad capacitor battery for a power distribution terminal, the discharge setter is connected to the switch chip.

[0017] Preferably, the model of the switch chip of the farad capacitor battery used for the power distribution terminal is TPS61089.

[0018] Preferably, in the farad capacitor battery for the power distribution terminal, the specification of the transformer inductor is selected according to the current output by the capacitor source group.

[0019] Preferably, the maximum current passing through the farad capacitor battery for the power distribution terminal is calculated by the following formula:

[0020] I=(Uout*Iout) / Ucap;

[0021] Wherein, I is the current passing through the transformer inductor L31, Ucap is the voltage across the farad capacitor, Uout is the output voltage of the farad capacitor discharge circuit, and Iout is the output current of the farad capacitor discharge circuit.

[0022] Preferably, the farad capacitor battery used for the power distribution terminal has a specification of the transformer inductor of 1.5uH / 12A.

[0023] Preferably, in the farad capacitor battery for the power distribution terminal, the voltage of the charging power supply connected to the charging unit is 1-2V higher than the rated voltage of the farad voltage.

[0024] Compared with the prior art, the present invention provides a farad capacitor battery for a power distribution terminal, which uses multiple farad capacitors in parallel to work, and does not require a voltage balancing circuit. At this time, the working voltage of the farad capacitor is stable, and there is no problem of too high voltage of the farad capacitor due to voltage balancing failure, which can ensure the long-term reliable operation of the farad capacitor; at the same time, the charging unit has a charging protector and a current limiter, and can use a low voltage to charge the farad capacitor. The voltage drop across the two ends of the current limiting resistor is small. Compared with the series connection method, under the same charging current, the loss is smaller. At the same time, when releasing the same energy, a farad circuit with a smaller capacity can be selected compared to the traditional series connection method, which can save circuit costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural block diagram of a farad capacitor battery of a power distribution terminal provided by the present invention;

[0026] Figure 2 is a circuit diagram of embodiment 1 provided by the present invention;

[0027] Figure 3 It is a circuit diagram of Example 2 provided by the present invention. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0029] Example 1

[0030] Please also read Figure 1-Figure 2 The present invention provides a farad capacitor battery for a power distribution terminal, comprising: a capacitor source group 1, a charging unit 2, and a discharging unit 3; one end of the capacitor source group 1 is grounded, and the other end is connected to the power generation unit; the charging unit 2 is connected to both ends of the capacitor source group 1; the capacitor source group 1 has a plurality of farad capacitors connected in parallel; the number of the farad capacitors is not specifically limited here, and is set according to the needs of use, as long as they are all connected in parallel;

[0031] The charging unit 2 includes a charging protector 22 and a current limiter 21; the current limiter 21 is connected to the capacitor source group 1 through the charging protector 22;

[0032] The discharge unit 3 includes a transformer switch 31 and a discharge setter 32; the transformer switch 31 is connected to the capacitor source group 1, and the discharge setter 32 is connected to the transformer switch 31. The transformer switch 31 is used to supply power to the outside; the discharge setter 32 is used to set the output voltage of the transformer switch 31, and the setting form is not limited. The preferred scheme is that the discharge setter 32 can be a controller, or a signal serial device connected to the controller. The present invention does not make specific limitations. The controller can be a processing device that can realize logic control inherent in an ordinary power distribution terminal, or a new independent controller can be added to set the output voltage of the transformer switch 31 through the discharge setter 32 according to the needs.

[0033] Specifically, the characteristics of the parallel working mode of farad capacitors are low charging voltage and less current limiting loss energy; constant voltage output, the energy stored in the farad capacitor can theoretically be completely released; no voltage equalization circuit is required between the farad capacitors, this circuit can be applied to the working mode of a single farad capacitor. If the capacity is not enough, the farad capacitor can be directly incorporated without modifying other circuit parameters.

[0034] As a preferred solution, in this embodiment, the charging protector 22 includes a voltage stabilizing diode V23 and a PNP transistor V22; the voltage stabilizing diode V23 has a cathode connected to the base of the PNP transistor V22, and a cathode connected to the grounded end of the capacitor source group 1;

[0035] The emitter of the PNP transistor V22 is connected to the ungrounded end of the capacitor source group 1;

[0036] The current limiter 21 is connected to the collector and the base of the PNP transistor V22 respectively.

[0037] Specifically, the voltage stabilizing diode V23 and the PNP transistor V22 form the charging protector 22 to prevent the farad capacitor in the capacitor source group 1 from being overcharged. When the set charging voltage is reached, the PNP transistor V22 is turned off, and charging is stopped at this time. The selection of the voltage stabilizing diode V23 is not specifically limited, and it is a commonly used voltage stabilizing diode in the art. The selection of the PNP transistor V22 is also not limited, and its preferred model is MMBT4401LT1G.

[0038] As a preferred solution, in this embodiment, the current limiter 21 includes a current limiting diode V21 and two current limiting resistors; one end of the two current limiters is respectively connected to the negative electrode of the current limiting diode V21, and the other end is respectively connected to the charging protector 22; the positive electrode of the current limiting diode V21 is connected to the charging interface.

[0039] As a preferred solution, in this embodiment, the voltage of the charging power source Vin connected to the charging unit 2 is 1-2V higher than the rated voltage of the farad voltage.

[0040] Specifically, in the charging circuit, Vin is the charging power supply, and the two current limiting resistors are current limiting resistor R20 and current limiting resistor R21. In order to reduce the energy loss on the current limiting resistor, the charging power supply is generally charged with a voltage 1-2V higher than the rated voltage of the farad capacitor. For example, when the maximum charging current is 0.5A, 4V charging is adopted, the current limiting resistor size is R=4V / 0.5A=8Ω, and the maximum loss of the current limiting resistor is P=UI=8*0.5=2W; compared with the series charging R=12V / 0.5A=24Ω, the loss is: P=UI=12*0.5=6W, which is one-third of the loss. In theory, the battery power damage is less than that of the series farad capacitor in the case of charging.

[0041] As a preferred solution, in this embodiment, the transformer switch 31 includes a switch chip D31 and a transformer inductor L31; the switch chip D31 is connected to the ungrounded end of the capacitor source group 1 through the transformer inductor L31. The specification of the transformer inductor L31 is preferably 1.5uH / 12A.

[0042] As a preferred solution, in this embodiment, the discharge setter 32 is connected to the switch chip D31.

[0043] As a preferred solution, in this embodiment, the model of the switch chip D31 is TPS61089.

[0044] Specifically, the discharge unit 3 uses the transformer switch 31 to adjust the output voltage, generally for boost output, and outputs a stable voltage value according to actual needs. The switch chip D31 is selected to be able to separate the working power supply from the boost power supply, and the boost input current is above 10A, to ensure that it can still work normally when the farad capacitor voltage is low. The preferred model of the switch chip D31 in the present invention adopts TI's TPS61089, with a maximum input current of 10A and a maximum output current of 12.6V and 3A. The other resistors or capacitors in the circuit are all peripheral circuits of this circuit, and are not specifically limited. Other peripheral circuits that cooperate with the switch chip D31 can also be used.

[0045] In the present invention, the switch chip D31 adopts TPS61089, which is not a conventional application of the TPS61089 model chip. The specific working principle is as follows (of course, the use principle of other models of chips with corresponding functions should also be as follows):

[0046] Please also read Figure 2 In the present invention, VOUT is charged, connected to the power supply circuit of the power distribution terminal, and supplies power to the power distribution terminal. The EN end of the switch chip D31 is controlled by the controller of the external power distribution terminal (equivalent to the function of the discharge setter 32, or the EN end is connected to the controller of the power distribution terminal through the discharge setter 32). The SW end of the switch chip D31 and the transformer inductor L31 form an oscillation circuit. After the farad capacitor is charged for a certain period of time, the EN end of the switch chip D31 is controlled by the controller to be a high level, and the discharge unit 3 starts to work normally. The specification of the transformer inductor L31 in the present invention is selected according to the size of the output current to select the appropriate current specification, with the maximum current that needs to pass through the transformer inductor L31 as the standard, and the calculation formula is: I = (Uout*Iout) / Ucap, where I is the current passing through the transformer inductor L31, Ucap is the voltage across the farad capacitor, Uout is the output voltage of the farad capacitor discharge circuit, and Iout is the output current of the farad capacitor discharge circuit.

[0047] Example 2

[0048] Please refer to Figure 3 The following takes the capacitor source group 1 as two 270F farad capacitors connected in parallel, the charging voltage Vin=4V, the discharging voltage Vout=12V, the threshold voltage of the voltage regulator diode V23 is 2.3V, the model of the PNP transistor V22 is MMBT4401LT1G, the switch chip D31 is TPS61089, and the inductance flow rate of the transformer inductor L31 is 1.5uH / 12A as an example for detailed description.

[0049] The threshold voltage of the voltage stabilizing diode V23 is 2.3V. When the capacitor voltage of the capacitor source group 1 is less than 2.3V, the voltage stabilizing diode V23 is not turned on, the voltage Vbe of the B and E terminals of the PNP transistor V22 is greater than 0.7V, the transistor is turned on, and the farad capacitor in the capacitor source group 1 is normally charged; when the voltage of the farad capacitor reaches 2.3V, the voltage stabilizing diode V23 is turned on, the voltage Vbe of the B and E terminals of the NPN transistor V22 is equal to 0, the PNP transistor V22 is turned off, and charging stops. When the voltage of the farad capacitor reaches 2.3V, that is, the voltage of the farad capacitor after full charge is 2.3V.

[0050] The voltage of Vout of this circuit is 12V when the farad capacitor is charged, the working power pin VIN of TPS61089 is connected to Vout, the working power of the chip is normal, the enable pin EN of the switch chip D31 is pulled high 5 minutes after the farad capacitor starts charging, and the boost circuit works normally.

[0051] When Vout outputs 12V 0.5A, according to the rule that the power at both ends of the switch chip D31 (i.e., the input end and the output end) is equal, when the voltage of the farad capacitor is 0.5V, I=P / 0.5=12*0.5 / 0.5=12A. The maximum flow rate of the transformer inductor L31 is 12A. At this time, the system works normally, so the farad capacitor can be discharged to at least 0.5V, that is, 80% of the energy stored in the farad capacitor is released. If a larger inductor flow rate is selected, more energy can be released. Under this condition, compared with the farad capacitor series mode, which can only release about 30% of the energy, it can release 50% more energy. According to E=0.5CU 2 , releasing the same energy, taking into account parameters such as the energy distribution curve of the farad capacitor, the parallel connection method is adopted, and the capacity of the parallel farad capacitor is more than 2 times smaller than that of the series farad capacitor.

[0052] It is understandable that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of the present invention, and all these changes or substitutions should fall within the protection scope of the claims attached to the present invention.

Claims

1. A farad capacitor battery for a power distribution terminal, characterized in that: include: Capacitor source group, charging unit, and discharging unit; One end of the capacitor source group is grounded, and the other end is connected to the discharge unit; the charging unit is connected to both ends of the capacitor source group; The capacitor source group comprises a plurality of farad capacitors connected in parallel with each other; The charging unit includes a charging protector and a current limiter; the current limiter, the charging protector, and the capacitor source group are connected in sequence; The discharge unit includes a voltage transformer and a discharge setter; the voltage transformer is connected to the capacitor source group, and the discharge setter is connected to the voltage transformer; The charging protector comprises a voltage stabilizing diode and a PNP transistor; the voltage stabilizing diode has a cathode connected to the base of the PNP transistor and a cathode connected to a grounded end of the capacitor source group; The emitter of the PNP transistor is connected to the ungrounded end of the capacitor source group; The current limiter is respectively connected to the collector and the base of the PNP transistor; The current limiter includes a current limiting diode and two current limiting resistors; one end of the two current limiting resistors is respectively connected to the cathode of the current limiting diode, and the other end is respectively connected to the charging protector; the anode of the current limiting diode is connected to the charging interface; The transformer switch comprises a switch chip and a transformer inductor; the switch chip is connected to an ungrounded end of the capacitor source group through the transformer inductor.

2. The farad capacitor battery for power distribution terminal according to claim 1, characterized in that: The discharge setter is connected to the switch chip.

3. The farad capacitor battery for power distribution terminal according to claim 1, characterized in that: The model of the switch chip is TPS61089.

4. The farad capacitor battery for power distribution terminal according to claim 1, characterized in that: The specification of the transformer inductor is selected according to the current output by the capacitor source group.

5. The farad capacitor battery for power distribution terminal according to claim 4, characterized in that: The maximum current through the transformer inductor is calculated by the following formula: I=(Uout*Iout) / Ucap; Wherein, I is the current passing through the transformer inductor (L31), Ucap is the voltage across the farad capacitor, Uout is the output voltage of the farad capacitor discharge circuit, and Iout is the output current of the farad capacitor discharge circuit.

6. The farad capacitor battery for power distribution terminal according to claim 5, characterized in that: The specification of the transformer inductor is 1.5uH / 12A.

7. The farad capacitor battery for power distribution terminal according to claim 1, characterized in that: The voltage of the charging power source connected to the charging unit is 1-2V higher than the rated voltage of the farad capacitor.

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