Intelligent electric energy meter

Abstract

The utility model discloses an intelligent electric energy meter comprising a main control unit, a cost control unit, a current sampling unit and a load switch on a live wire, a load driving circuit used for driving the load switch, and a voltage sampling unit used for collecting voltage information. The current sampling unit is connected with the main control unit through the current zero-crossing detection circuit so as to send collected current zero-crossing data to the main control unit; the voltage sampling unit is connected with the main control unit through a voltage zero detection circuit so as to send acquired voltage zero-crossing data to the main control unit; the main control unit is respectively connected with the charge control unit and the load driving circuit; when the cost of a customer is used up or recharged, the main control unit can send a control signal to the load driving circuit to drive the load switch to make a switching-off or switching-on action when the current passes zero or the voltage passes zero, so that the arc discharge phenomenon of the load switch is avoided, the working stability of the load switch is improved, and the working life of the load switch is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of smart energy meters, and in particular to a smart energy meter. Background Technology

[0002] As smart home construction progresses, it becomes necessary to collect data on the operating status and power consumption of various devices used in users' homes, so that users can understand the power consumption of smart devices.

[0003] Power acquisition typically consists of a metering chip, a microprocessor, storage, and communication components. The metering chip samples both voltage and current simultaneously. Internally, it integrates multiple second-order sigma-delta ADCs, a reference voltage circuit, and digital signal processing circuits for measuring all power, energy, RMS values, power factor, and frequency. It can measure active power, reactive power, apparent power, active and reactive quantities, as well as parameters such as current, RMS voltage, power factor, phase angle, and frequency.

[0004] Currently, the widely used smart sockets that can count electricity consumption use a built-in hardware module with power detection function to count electricity consumption. However, the production cost of such hardware modules is high and they consume a lot of power. The data obtained by real-time power detection through hardware is also inaccurate. There are also electrical devices with smart interaction on the market, or the distribution box is modified to install smart load switches.

[0005] When there is insufficient funds, existing electricity meters often directly disconnect the load switch, which can easily damage the load switch contacts and shorten its service life when disconnecting under high current.

[0006] Therefore, a new technical solution needs to be developed to address the above problems. Utility Model Content

[0007] In view of this, the present invention addresses the deficiencies of the existing technology, and its main purpose is to provide a smart energy meter that does not immediately trip the circuit when the customer's credit is used up or recharged. Instead, it sends a control signal to the load drive circuit to drive the load switch to perform tripping or closing actions only when the collected current or voltage data crosses zero, thereby avoiding arcing of the load switch and improving the working stability and service life of the load switch.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] The smart energy meter includes a main control unit, a prepayment control unit, a current sampling unit and a load switch on the live wire, a load drive circuit for driving the load switch, and a voltage sampling unit for collecting voltage information.

[0010] The current sampling unit is connected to the main control unit through a current zero-crossing detection circuit to send the collected current zero-crossing data to the main control unit;

[0011] The voltage sampling unit is connected to the main control unit through a voltage zero detection circuit to send the collected voltage zero-crossing data to the main control unit;

[0012] The main control unit is connected to the cost control unit and the load drive circuit respectively;

[0013] When a customer's account is depleted or recharged, the main control unit receives a signal from the fee control unit and, based on the collected current and voltage zero-crossing data, sends a control signal to the load drive circuit to drive the load switch to perform a tripping or closing action.

[0014] As a preferred embodiment, the load drive circuit includes chip U13, resistors R52, R53, R54, capacitor C2R, resistors R602, R62, and R61.

[0015] Pins 4 and 1 of chip U13 are connected to the load switch respectively. Resistors R52 and R602 are connected in series. The series connection of resistors R52 and R602 is connected to pin 3 of chip U13. The non-series connection of resistor R52 is connected to the main control unit. The non-series connection of resistor R602 and pin 2 of chip U13 are both grounded.

[0016] Resistors R53 and R54 are connected in series. The series connection point of resistors R53 and R54 is connected to pin 6 of chip U13. The non-series connection point of resistor R53 is connected to the main control unit. The non-series connection point of resistor R54 is grounded.

[0017] Pin 5 of chip U13 is grounded through capacitor C2R. One end of resistor R61 is connected to pin 5 of chip U13, and the other end of resistor R61 is used to connect to the 18V voltage terminal. Resistors R62 and R61 are connected in parallel.

[0018] As a preferred embodiment, the system also includes an LCD screen, which is connected to the main control unit.

[0019] As a preferred embodiment, it also includes an energy card reading and writing unit, wherein the fee control unit includes a local fee control unit, which is connected to the main control unit and the energy card reading and writing unit respectively.

[0020] As a preferred embodiment, the system also includes a storage unit for storing local expense control unit data, the storage unit being connected to the main control unit.

[0021] As a preferred embodiment, it also includes a communication unit, wherein the fee control unit includes a remote fee control unit, the remote fee control unit is connected to the communication unit, and the remote fee control unit is connected to the main control unit.

[0022] Compared with the prior art, this utility model has obvious advantages and beneficial effects. Specifically, as can be seen from the above technical solution, through the cooperation of the main control unit, the fee control unit, the current zero-crossing detection circuit, the voltage zero-crossing detection circuit and the load drive circuit, it can prevent the circuit from being immediately cut off when the customer's fee is used up or recharged. Instead, it sends a control signal to the load drive circuit to drive the load switch to perform the opening or closing action when the collected current zero-crossing or voltage zero-crossing data is collected. This avoids the arcing phenomenon of the load switch and improves the working stability and service life of the load switch.

[0023] Secondly, by combining local and remote fee control units, different payment methods can be implemented, improving ease of use.

[0024] To more clearly illustrate the structural features and effects of this utility model, the following detailed description of this utility model is provided in conjunction with the accompanying drawings and specific embodiments. Attached Figure Description

[0025] Figure 1 This is a general control block diagram of an embodiment of the present invention.

[0026] Figure 2 This is a schematic diagram of the load drive circuit according to an embodiment of the present invention.

[0027] Explanation of reference numerals in the attached diagram:

[0028] 11. Voltage sampling unit; 12. Current sampling unit

[0029] 13. Voltage zero detection circuit 14. Current zero-crossing detection circuit

[0030] 15. Main control unit; 16. LCD display screen

[0031] 17. Fee control unit; 18. Load drive circuit

[0032] 19. Load switch. Detailed Implementation

[0033] Please refer to Figure 1 and Figure 2 As shown, it illustrates the specific structure of an embodiment of the present invention. A smart energy meter includes a main control unit 15, a prepaid control unit 17, an LCD display 16, a current sampling unit 12 and a load switch 19 on the live wire, a load driving circuit 18 for driving the load switch 19, and a voltage sampling unit 11 for collecting voltage information.

[0034] The current sampling unit 12 is connected to the main control unit 15 through the current zero-crossing detection circuit 14 to send the collected current zero-crossing data to the main control unit 15;

[0035] The voltage sampling unit 11 is connected to the main control unit 15 through the voltage zero detection circuit 13 to send the collected voltage zero-crossing data to the main control unit 15;

[0036] The main control unit 15 is connected to the cost control unit 17 and the load drive circuit 18 respectively;

[0037] The load drive circuit 18 includes a chip U13, resistors R52, R53, R54, capacitor C2R, resistors R602, R62, and R61.

[0038] Pins 4 and 1 of chip U13 are connected to load switch 19 respectively. Resistors R52 and R602 are connected in series. The series connection of resistors R52 and R602 is connected to pin 3 of chip U13. The non-series connection of resistor R52 is connected to main control unit 15. The non-series connection of resistor R602 and pin 2 of chip U13 are both grounded.

[0039] Resistors R53 and R54 are connected in series. The series connection point of resistors R53 and R54 is connected to pin 6 of chip U13. The non-series connection point of resistor R53 is connected to the main control unit 15. The non-series connection point of resistor R54 is grounded.

[0040] Pin 5 of chip U13 is grounded through capacitor C2R. One end of resistor R61 is connected to pin 5 of chip U13, and the other end of resistor R61 is used to connect to the 18V voltage terminal. Resistors R62 and R61 are connected in parallel.

[0041] When a customer's account is depleted or recharged, the main control unit 15 receives a signal from the fee control unit 17 and, based on the collected current and voltage zero-crossing data, sends a control signal to the load drive circuit 18 to drive the load switch 19 to perform a tripping or closing action. Specifically:

[0042] When the customer's funds are used up, the main control unit 15 receives the signal from the fee control unit 17 and sends a control signal to the load drive circuit 18 to drive the load switch 19 to perform a tripping action based on the collected current zero-crossing condition.

[0043] When a customer recharges, the main control unit 15 receives the signal from the fee control unit 17 and sends a control signal to the load drive circuit 18 based on the collected voltage zero-crossing data to drive the load switch 19 to close.

[0044] The LCD screen 16 is connected to the main control unit 15.

[0045] It also includes an energy card reader / writer unit, a communication unit, and a storage unit for storing data from the local prepayment control unit 17. The prepayment control unit 17 includes a local prepayment control unit 17 and a remote prepayment control unit 17. The local prepayment control unit 17 is connected to the main control unit 15 and the energy card reader / writer unit, respectively. The storage unit is connected to the main control unit 15.

[0046] The remote fee control unit 17 is connected to the communication unit and the main control unit 15.

[0047] The key design feature of this utility model is that, through the cooperation of the main control unit, the fee control unit, the current zero-crossing detection circuit, the voltage zero-crossing detection circuit, and the load drive circuit, it can prevent the circuit breaker from being immediately tripped when the customer's fees are used up and recharged. Instead, it sends a control signal to the load drive circuit to drive the load switch to perform tripping or closing actions only when the collected current or voltage zero-crossing data is detected. This avoids arcing in the load switch and improves the working stability and service life of the load switch.

[0048] Secondly, by combining local and remote fee control units, different payment methods can be implemented, improving ease of use.

[0049] The above description is merely a preferred embodiment of the present utility model and does not constitute any limitation on the technical scope of the present utility model. Therefore, any minor modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model shall still fall within the scope of the technical solution of the present utility model.

Claims

1. A smart energy meter, characterized in that: It includes a main control unit, a prepaid control unit, a current sampling unit and a load switch on the live wire, a load drive circuit for driving the load switch, and a voltage sampling unit for collecting voltage information. The current sampling unit is connected to the main control unit through a current zero-crossing detection circuit to send the collected current zero-crossing data to the main control unit; The voltage sampling unit is connected to the main control unit through a voltage zero detection circuit to send the collected voltage zero-crossing data to the main control unit; The main control unit is connected to the cost control unit and the load drive circuit respectively; When a customer's account is depleted or recharged, the main control unit receives a signal from the fee control unit and, based on the collected current and voltage zero-crossing data, sends a control signal to the load drive circuit to drive the load switch to perform a tripping or closing action.

2. The smart energy meter according to claim 1, characterized in that: The load drive circuit includes chip U13, resistors R52, R53, R54, capacitor C2R, resistors R602, R62, and R61. Pins 4 and 1 of chip U13 are connected to the load switch respectively. Resistors R52 and R602 are connected in series. The series connection of resistors R52 and R602 is connected to pin 3 of chip U13. The non-series connection of resistor R52 is connected to the main control unit. The non-series connection of resistor R602 and pin 2 of chip U13 are both grounded. Resistors R53 and R54 are connected in series. The series connection point of resistors R53 and R54 is connected to pin 6 of chip U13. The non-series connection point of resistor R53 is connected to the main control unit. The non-series connection point of resistor R54 is grounded. Pin 5 of chip U13 is grounded through capacitor C2R. One end of resistor R61 is connected to pin 5 of chip U13, and the other end of resistor R61 is used to connect to the 18V voltage terminal. Resistors R62 and R61 are connected in parallel.

3. The smart energy meter according to claim 1, characterized in that: It also includes an LCD screen, which is connected to the main control unit.

4. The smart energy meter according to claim 1, characterized in that: It also includes an energy card reading and writing unit, and the fee control unit includes a local fee control unit, which is connected to the main control unit and the energy card reading and writing unit respectively.

5. The smart energy meter according to claim 4, characterized in that: It also includes a storage unit for storing local expense control unit data, which is connected to the main control unit.

6. The smart energy meter according to claim 5, characterized in that: It also includes a communication unit, and the fee control unit includes a remote fee control unit, which is connected to the communication unit and the remote fee control unit is connected to the main control unit.

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