Power switching circuit using supercapacitor charging and discharging

Abstract

The utility model relates to a power switching circuit utilizing supercapacitor charging and discharging, which comprises current limiting resistors R1, R2, and R3; SMD ceramic capacitors C1, C2, C3, and C4; SMD dual diodes D1 and D2; power supply chips U1 and U2; an energy storage unit supercapacitor E1; one end of the SMD ceramic capacitor C1 is connected to a system GND and the other end is connected to a circuit input power supply MHVDD; an input end VIN of the power supply chip U1 is connected to an input power supply MHVDD, a GND end is connected to a system GND, and an output end VOUT is connected to a diode D1; one end of the SMD ceramic capacitor C2 is connected to D1 and the other end is connected to the system GND; and the other end of the SMD dual diode D1 is connected to the current limiting resistor R1.

Description

Technical Field

[0001] The utility model relates to a power supply switching circuit utilizing super capacitor charging and discharging. Background Art

[0002] As a basic introduction, the core of smart meter includes power system (including power switching circuit), microprocessor (MCU), metering chip, memory unit and communication module. The microprocessor is responsible for data acquisition, processing and storage; the memory unit is used to store historical data; the supercapacitor charging and discharging circuit is the core component of the power switching circuit of the smart meter, and plays a great role in the power-on and power-off state of the smart meter. The supercapacitor charging and discharging circuit includes charging circuit, discharging circuit, anti-leakage diode, current limiting circuit and control circuit.

[0003] As an improvement to charging and discharging, the utility model improves the core component supercapacitor so that no chemical reaction occurs during the charging process. The entire charging process is reversible, so the supercapacitor can be repeatedly charged and discharged. When the power grid is out of power, the power switching circuit of the smart meter automatically switches to power the MCU. At the moment of power outage, the MCU detects the occurrence of an external power failure event, and needs to maintain a period of time to complete the recording of power outage data and event reporting, which will generate a lot of power consumption. The greater the frequency of power outage events, the more obvious the consumption of lithium battery power. Therefore, the supercapacitor charging and discharging circuit plays a vital role. At the moment of power outage, the supercapacitor is switched in time to power the entire system, thereby greatly extending the life of the lithium battery, and solving the problems of untimely event storage, untimely event reporting, and data anomalies caused by system reset outage due to insufficient power supply after the power grid is out of power.

[0004] The utility model combines the supercapacitor charge and discharge management system to effectively deal with the problem of short life of lithium batteries, and also solves the problems of lithium battery exhaustion, aging and failure, which cause important data loss, abnormality and clock disorder of the energy meter. Utility Model Content

[0005] The technical problem to be solved by the utility model is generally to provide a power switching circuit using supercapacitor charging and discharging, so as to realize automatic power switching after power failure of the power grid, achieve economy, environmental protection, high efficiency and long life; and increase the stability and reliability of the control system.

[0006] In order to solve the above problems, the technical solution adopted by the utility model is:

[0007] In order to realize automatic switching, the utility model adopts a power switching circuit using supercapacitor charging and discharging, including current limiting resistors R1, R2, R3; SMD ceramic capacitors C1, C2, C3, C4; SMD dual diodes D1, D2; power chips U1, U2; energy storage unit supercapacitor E1;

[0008] One end of the chip ceramic capacitor C1 is connected to the system GND and the other end is connected to the circuit input power supply MHVDD;

[0009] The input terminal VIN of the power chip U1 is connected to the input power MHVDD, the GND terminal is connected to the system GND, and the output terminal VOUT is connected to the diode D1;

[0010] One end of the chip capacitor C2 is connected to D1 and the other end is connected to the system GND;

[0011] The other end of the SMD dual diode D1 is connected to the current limiting resistor R1.

[0012] The other end of the current limiting resistor R1 is connected to the energy storage unit supercapacitor E1. One end of the energy storage unit supercapacitor E1 is connected to the VIN end of the power chip U2, and the other end is connected to the system GND.

[0013] The GND pin of the power chip U2 is connected to the system GND, the VOUT end of the power chip U2 is connected to the SMD dual diode D2 and the SMD ceramic capacitor C3, the other end of the SMD dual diode D2 is connected to the MCU power supply pin MVDD, and the other end of the SMD ceramic capacitor C3 is connected to the system GND;

[0014] One end of the current limiting resistor R2 is connected to E1, and the other end is connected to the MCU ADC port network marked as Power monitoring. Power monitoring is connected to the current limiting resistor R3 and the SMD ceramic capacitor C4. The other ends of the current limiting resistor R3 and the SMD ceramic capacitor C4 are connected to the system GND.

[0015] As a further improvement of the above technical solution: the current limiting resistors R1, R2, and R3 are chip thick film resistors.

[0016] As a further improvement of the above technical solution, the SMD ceramic capacitor C1 is a filter capacitor of the power supply MHVDD.

[0017] As a further improvement of the above technical solution, the SMD ceramic capacitor C2 is a filter capacitor at the VOUT end of the power chip U1.

[0018] As a further improvement of the above technical solution, the SMD ceramic capacitor C3 is a filter capacitor at the VOUT end of the power chip U2.

[0019] As a further improvement of the above technical solution, the SMD ceramic capacitor C4 is a filter capacitor for network power monitoring.

[0020] The beneficial effects of the utility model are: 1. The service life of the lithium battery is greatly improved; 2. The problem of data storage and event reporting after power outage in the power grid is solved, and the stability of the system is enhanced; 3. The circuit is simple, the cost is low, and it has strong adaptability and practicality; 4. The supercapacitor circuit is economical, environmentally friendly, high-efficiency and long-life. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a circuit diagram of the utility model.

[0022] As an introduction to components:

[0023] R1 is a current limiting resistor, the maximum operating voltage is preferably 200V, and the accuracy is preferably 1%.

[0024] R2 and R3 are sampling resistors, the maximum working voltage is preferably 50V and the accuracy is preferably 1%.

[0025] C1 is a filter capacitor, and the maximum working voltage is preferably 50V

[0026] C2, C3, C4 are filter capacitors, and the maximum working voltage is preferably 16V

[0027] D1 and D2 are Schottky dual diodes, the maximum operating voltage is preferably 30V, and the maximum operating current is preferably 0.2A

[0028] E1 is a supercapacitor, preferably with a rated voltage of 5.5V and a capacity of 1.5F

[0029] The power chip U1 preferably has a maximum operating voltage of 40V, a maximum output current of 0.3A, and an output voltage of 5.3V

[0030] The power chip U2 preferably has a maximum static power consumption of 1uA, a maximum operating voltage of 12V, and a maximum output current of 500mA. DETAILED DESCRIPTION

[0031] like Figure 1 As shown, the power switching circuit using supercapacitor charging and discharging in this embodiment is obvious to those skilled in the art for combining multiple technical solutions of the utility model. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiment of the utility model. The contents related to the invention point introduced in this patent are ignored or simplified as conventional technologies.

[0032] This energy meter uses a supercapacitor charging and discharging circuit to achieve power switching.

[0033] The circuit includes SMD thick film resistors R1, R2, R3; SMD ceramic capacitors C1, C2, C3, C4; SMD dual diodes D1, D2; power chips U1, U2; energy storage unit super capacitor E1;

[0034] One end of the chip ceramic capacitor C1 is connected to the system GND, and the other end is connected to the circuit input power supply MHVDD; the input end VIN of the power chip U1 is connected to the input power supply MHVDD, the GND end is connected to the system GND, and the output end VOUT is connected to the diode D1; one end of C2 is connected to D1, and the other end is connected to the system GND, the other end of D1 is connected to the current limiting resistor R1, the other end of R1 is connected to E1, one end of E1 is connected to the VIN end of the power chip U2, and the other end is connected to the system GND, the GND foot of U2 is connected to the system GND, the VOUT end of U2 is connected to D2 and C3, the other end of D2 is connected to the MCU power supply pin MVDD, and the other end of C3 is connected to the system GND; one end of R2 is connected to E1, and the other end is connected to the MCU ADC port network marked as Power monitoring, Power monitoring is connected to R3 and C4, and the other ends of R3 and C4 are connected to the system GND.

[0035] C1 is the filter capacitor of the power supply MHVDD, C2 is the filter capacitor of the VOUT end of the power chip U1, C3 is the filter capacitor of the VOUT end of the power chip U2, and C4 is the filter capacitor of the network Power monitoring.

[0036] The power monitoring ADC port samples the power of supercapacitor E1 by dividing the voltage between R2 and R3 resistors and calculates accurate power data.

Claims

1. A power switching circuit utilizing supercapacitor charging and discharging, characterized in that: Including current limiting resistors R1, R2, R3; SMD ceramic capacitors C1, C2, C3, C4; SMD dual diodes D1, D2; power chips U1, U2; energy storage unit super capacitor E1; One end of the chip ceramic capacitor C1 is connected to the system GND and the other end is connected to the circuit input power supply MHVDD; The input terminal VIN of the power chip U1 is connected to the input power MHVDD, the GND terminal is connected to the system GND, and the output terminal VOUT is connected to the diode D1; One end of the chip capacitor C2 is connected to D1 and the other end is connected to the system GND; The other end of the SMD dual diode D1 is connected to the current limiting resistor R1. The other end of the current limiting resistor R1 is connected to the energy storage unit supercapacitor E1. One end of the energy storage unit supercapacitor E1 is connected to the VIN end of the power chip U2, and the other end is connected to the system GND. The GND pin of the power chip U2 is connected to the system GND, the VOUT end of the power chip U2 is connected to the SMD dual diode D2 and the SMD ceramic capacitor C3, the other end of the SMD dual diode D2 is connected to the MCU power supply pin MVDD, and the other end of the SMD ceramic capacitor C3 is connected to the system GND; One end of the current limiting resistor R2 is connected to the energy storage unit supercapacitor E1, and the other end is connected to the MCU ADC port network marked as Powermonitoring. Power monitoring connects the current limiting resistor R3 and the SMD ceramic capacitor C4. The other ends of the current limiting resistor R3 and the SMD ceramic capacitor C4 are connected to the system GND.

2. The power switching circuit utilizing supercapacitor charging and discharging according to claim 1, characterized in that: The current limiting resistors R1, R2, and R3 are thick film chip resistors.

3. The power switching circuit using supercapacitor charging and discharging according to claim 1, characterized in that: The chip ceramic capacitor C1 is the filter capacitor of the power supply MHVDD.

4. The power switching circuit utilizing supercapacitor charging and discharging according to claim 1, characterized in that: The chip ceramic capacitor C2 is the filter capacitor at the VOUT end of the power chip U1.

5. The power switching circuit using supercapacitor charging and discharging according to claim 1, characterized in that: The chip ceramic capacitor C3 is the filter capacitor at the VOUT end of the power chip U2.

6. The power switching circuit using supercapacitor charging and discharging according to claim 1, characterized in that: The SMD ceramic capacitor C4 is the filter capacitor for network power monitoring.

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