Modular electric energy meter and voltage stabilizing circuit thereof

Abstract

The invention relates to a modular electric energy meter and a voltage stabilizing circuit thereof, and belongs to the field of electric energy meters. The voltage stabilizing circuit comprises a detection end used for detecting the plugging condition of an electric energy meter management module, a virtual load and a switching device, the detection end is used for controlling the switching device to be switched on when the management module is pulled out, and the switching device and the virtual load are connected to the two ends of a main circuit voltage in series. According to the voltage stabilizing circuit provided by the invention, the plugging condition of the management module can be detected by using the detection end, when the management module is pulled out, the virtual load can be added to the two ends of the voltage of the main circuit by controlling the switching device to be switched on, and when the management module is pulled out, the no-load phenomenon does not exist in the main circuit, so that the output voltage of the auxiliary circuit is stable; normal operation of the metering module is ensured, and stability and service life of the electric energy meter can be improved.

Description

Technical Field

[0001] The invention relates to a modular electric energy meter and a voltage stabilizing circuit thereof, belonging to the field of electric energy meters. Background Art

[0002] As an intelligent terminal of the power grid, the energy meter not only has basic metering functions, but also has many functions such as tiered electricity prices, time-of-use rates, electricity consumption control, communication interaction, etc. At present, the new generation of energy meters in the industry adopts a modular design solution, which independently designs the metering module and the management module and then assembles them into one. In this mode, when the management module fails, only the management module needs to be replaced, which will not affect the function of the metering module, ensuring the smooth progress of electricity metering.

[0003] Among them, the metering module can be responsible for the metering of electric energy, and the management module can convert the metered electricity of the metering module into metered electric energy and upload it to the electricity fee management server through the network, the power supply company management and the user's electricity consumption query. The metering module can also correctly record the hot plug events of the management module.

[0004] The power supply of the energy meter usually adopts a switching power supply, which has dual outputs, including main output and auxiliary output. The main output mainly provides power for the management module, and the auxiliary output mainly provides power for the metering module. Due to the characteristics of the switching power supply, the main output voltage will affect the auxiliary output voltage. Therefore, when the management module is unplugged, the main output voltage will instantly decrease significantly, which will cause the auxiliary output voltage to drop, and further affect the stability of the metering module. Summary of the invention

[0005] The object of the present invention is to provide a modular electric energy meter and a voltage stabilizing circuit thereof, so as to solve the problem in the prior art that the stability of the operation of the metering module will be affected when the management module of the modular electric energy meter is unplugged.

[0006] To achieve the above object, the solution of the present invention includes: A voltage stabilizing circuit for a modular electric energy meter of the present invention comprises: a detection end for detecting the plugging and unplugging status of an electric energy meter management module, a virtual load and a switch device; the detection end is used to control the conduction of the switch device when the management module is unplugged, and the switch device and the virtual load are connected in series at both ends of the main circuit voltage.

[0007] Furthermore, the detection end outputs a high level when the management module is unplugged, the switching device is an NPN transistor, the virtual load is connected in series between the positive pole of the power supply and the collector of the NPN transistor, the emitter of the NPN transistor is grounded, and the detection end is connected to the base of the NPN transistor.

[0008] Furthermore, the detection end is also connected to the positive pole of the power supply through a pull-up resistor; when the management module is inserted into the energy meter, the detection end level is pulled down, and when the management module is unplugged, the detection end level is pulled up through the pull-up resistor.

[0009] Furthermore, a current limiting resistor is connected between the detection terminal and the base of the NPN transistor.

[0010] Further, the dummy load includes two resistors connected in parallel.

[0011] A modular electric energy meter of the present invention comprises the above-mentioned voltage stabilizing circuit of the modular electric energy meter.

[0012] The beneficial effects of the present invention are as follows: the present invention is a pioneering invention. The voltage stabilizing circuit of the present invention can detect the plugging and unplugging status of the management module by using the detection end. When the management module is unplugged, by controlling the conduction of the switch device, a virtual load can be added to both ends of the main circuit voltage, so that there is no no-load phenomenon in the main circuit, thereby stabilizing the output voltage of the auxiliary circuit, thereby ensuring the normal operation of the metering module, and thereby improving the stability and service life of the electric energy meter. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of a voltage stabilizing circuit for a modular electric energy meter provided by an embodiment of the present invention; Figure 2 It is a structural schematic diagram of another voltage stabilizing circuit for a modular electric energy meter provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0014] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0015] The electric energy meter adopts a modular design. The metering module is responsible for the metering of electric energy. The management module can convert the metered electric energy into metered electric energy by reading the metering module's metering power and upload it to the electricity fee management server through the network, for power grid company management and user electricity query. During the use of the electric energy meter, there may be a situation where the management function of the meter is affected due to damage to the management module, so the management module needs to be replaced.

[0016] The replacement of management modules involves hot-swap technology, which means hot-swap technology. Without turning off the system power, the module or board can be inserted or removed from the system without affecting the normal operation of the system, thereby improving the system's reliability, rapid maintainability, redundancy, and timely disaster recovery capabilities. Therefore, it is very important to maintain the stability of the system voltage.

[0017] Since the power supply of the energy meter usually adopts a switching power supply, the switching power supply has dual outputs, including the main output and the auxiliary output. The main output mainly provides power for the management module, and the auxiliary output mainly provides power for the metering module. Since the switching power supply usually adopts multiple sets of secondary windings of the transformer, there is mutual inductance, so the voltage of the main output will affect the voltage of the auxiliary output. When the management module is inserted, there is no no-load situation in the main output and the auxiliary output, and the voltage of the two outputs is relatively stable; when the management module is unplugged, the main output is no-loaded, and the sudden change of the main load will cause the auxiliary output voltage to drop, which in turn affects the stability of the metering module operation.

[0018] In view of the problem in the prior art that when the management module is unplugged, the main output suddenly becomes unloaded, causing the auxiliary output voltage to drop, thereby affecting the stability of the metering module operation, an embodiment of the present invention provides a voltage stabilizing circuit for a modular electric energy meter, which is used to control the conduction of the switching device when the management module is unplugged, so that a virtual load can be added to both ends of the main voltage, so that the voltage of the auxiliary output can be kept more stable, thereby ensuring the stable operation of the metering module, and further improving the stability and service life of the electric energy meter.

[0019] An embodiment of a voltage stabilizing circuit for a modular electric energy meter: Embodiment 1: Figure 1 is a schematic diagram of a voltage stabilizing circuit for a modular electric energy meter provided by an embodiment of the present invention, such as Figure 1 As shown, the voltage stabilizing circuit includes: a virtual load 20, a switch device 10 and a detection terminal for detecting the plugging and unplugging of the power meter management module. The detection terminal is used to control the switching device 10 to conduct when the management module (not shown) is unplugged, and the switching device 10 and the virtual load 20 are connected in series at both ends of the power supply VP1.

[0020] Among them, the power supply VP1 is the main circuit voltage.

[0021] The virtual load 20 may include one resistor or two or more resistors connected in parallel, which is not particularly limited in the present application. The virtual load circuit 20 including two resistors connected in parallel is used as an example for illustrative description. The two resistors connected in parallel are respectively a first resistor R1 and a second resistor R2.

[0022] The first resistor R1 and the second resistor R2 can be fixed resistors or sliding resistors, which is not particularly limited in the present invention. For the convenience of integration, the present invention will be described hereinafter by taking the first resistor R1 and the second resistor R2 as fixed resistors as an example.

[0023] The present application does not specifically limit the resistance values ​​of the first resistor R1 and the second resistor R2.

[0024] The detection end can detect the plug-in and unplugging status of the management module of the electric energy meter, and output a position signal COM-RQ to the switch device according to the plug-in and unplugging status of the management module to control the on or off of the switch device 10. When the management module is inserted, the switch device 10 is controlled to be off, and when the management module is unplugged, the switch device 10 is controlled to be on.

[0025] The switch device 10 is used to be turned on or off under the control of the detection end.

[0026] It is understandable that when a management module fails, it is necessary to replace it with a new management module. At this time, the management module needs to be unplugged. Since the power supply voltage of the management module is provided by the main output power supply end, when the management module is unplugged, the main output power supply end will be unloaded, which will cause the auxiliary output voltage to drop. Since the auxiliary output is also connected to the metering module, the reduced auxiliary output voltage cannot provide the correct working voltage for the metering module, which will cause the voltage of the metering module to be unstable.

[0027] Therefore, when the management module is unplugged, the switch device 10 needs to control the virtual load 20 to join the loop between the positive electrode of the power supply VP1 and the ground GND to increase the load of the main output. The addition of the virtual load 20 can make the voltage of the auxiliary output relatively stable.

[0028] When the management module is always in the inserted state, or when the management module is just replaced, the main output power supply end is not unloaded, the voltage of the main output is relatively stable, and under the influence of mutual inductance, the voltage of the auxiliary output is also relatively stable. If the virtual load 20 is added to the loop between the positive pole of the power supply VP1 and the ground GND, the power consumption of the energy meter will increase. Therefore, in order to reduce power consumption, the switch device 10 needs to control the virtual load 20 to exit the loop between the positive pole of the power supply VP1 and the ground GND.

[0029] The switch device 10 may include an electronic relay, a metal-oxide-semiconductor field-effect transistor (MOSFET), a bipolar junction transistor (BJT), etc., and the present invention does not specifically limit this. In order to reduce cost and impedance, the embodiment 1 provided by the present invention takes the switch device 10 including an NPN transistor Q1 as an example for exemplary description.

[0030] In the case where the switch device 10 includes an NPN transistor Q1, the voltage stabilizing circuit also includes a pull-up resistor R3. The pull-up resistor R3 may be a fixed resistor or a sliding resistor, and the present application does not specifically limit this. For the convenience of integration, the embodiments of the present application are described exemplarily by taking the pull-up resistor R3 as a fixed resistor. The resistance value of the pull-up resistor R3 is not specifically limited in the present application.

[0031] Specifically, the detection end is connected to the base of the transistor Q1, and is connected to the positive electrode of the power supply VP1 through the pull-up resistor R3; the first resistor R1 and the second resistor R2 are connected in parallel and in series between the positive electrode of the power supply VP1 and the collector of the transistor Q1, and the emitter of the transistor Q1 is grounded GND.

[0032] When the management module is inserted, the in-place signal COM-RQ defaults to a low level, the control transistor Q1 is turned off, and the first resistor R1 and the second resistor R2 both exit the loop between the positive electrode of the power supply VP1 and the ground GND. When the management module is unplugged, the level of the in-place signal COM-RQ output by the detection end is pulled up through the pull-up resistor R3, the control transistor Q1 is turned on, and the first resistor R1 and the second resistor R2 are both added to the loop between the positive electrode of the power supply VP1 and the ground GND.

[0033] In order to reduce the damage to the transistor Q1 caused by the excessive output current of the in-position signal COM-RQ, as an optional implementation, the voltage stabilizing circuit provided in the embodiment of the present application also includes a current limiting resistor R4.

[0034] When the voltage stabilizing circuit includes a current limiting resistor R4, the current limiting resistor R4 is connected between the detection terminal and the base of the transistor Q1.

[0035] The fourth resistor R4 may be a fixed resistor or a sliding resistor, and the present application does not specifically limit this. For the convenience of integration, the present application will take the fourth resistor R4 as an example of a fixed resistor for illustrative description. The present application does not specifically limit the resistance value of the fourth resistor R4.

[0036] A voltage stabilizing circuit for a modular electric energy meter provided in an embodiment of the present invention can detect the plugging and unplugging status of a management module by using a detection end. When the management module is unplugged, a virtual load can be added to both ends of a power supply for the metering module by controlling the conduction of a switch device. When the management module is unplugged, there is no no-load phenomenon in the main circuit, so that the output voltage of the auxiliary circuit can be stabilized, thereby ensuring the normal operation of the metering module, and further improving the stability and service life of the electric energy meter.

[0037] Embodiment 2: The difference between this embodiment and embodiment 1 is that the transistor Q1 in the switch device 10 is replaced by the relay J1, and the other circuit components are not changed. The circuit principle can be referred to Figure 2 .

[0038] Figure 2 is a schematic diagram of the structure of another voltage stabilizing circuit for a modular electric energy meter provided by an embodiment of the present invention, such as Figure 2 As shown, the detection end is connected to the first end of the relay J1 through the current limiting resistor R4, and the detection end is also connected to the power supply VP1 through the pull-up resistor R3. The second and fourth ends of the relay J1 are both grounded GND, and the third end of the relay J1 is connected to the power supply VP1 through the virtual load 20.

[0039] When the management module is inserted, the in-place signal COM-RQ defaults to a low level, the control relay J1 is turned off, and the first resistor R1 and the second resistor R2 both exit the loop between the positive electrode of the power supply VP1 and the ground GND. When the management module is unplugged, the level of the in-place signal COM-RQ output by the detection end is pulled up through the pull-up resistor R3, the control relay J1 is turned on, and the first resistor R1 and the second resistor R2 are both added to the loop between the positive electrode of the power supply VP1 and the ground GND.

[0040] An embodiment of the present invention provides a voltage stabilizing circuit for a metering module of a modular electric energy meter. By using a detection end, the plugging and unplugging status of a management module can be detected. When the management module is unplugged, a virtual load can be added to both ends of the power supply for the metering module by controlling the conduction of a switch device. When the management module is unplugged, there is no no-load phenomenon in the main circuit, so that the output voltage of the auxiliary circuit can be stabilized, thereby ensuring the normal operation of the metering module, and further improving the stability and service life of the electric energy meter.

[0041] An embodiment of a modular electric energy meter: An embodiment of the present invention further provides a modular electric energy meter, comprising the voltage stabilizing circuit of the modular electric energy meter in any of the aforementioned implementations.

[0042] A modular electric energy meter provided in an embodiment of the present invention can achieve the same beneficial effects as the voltage stabilizing circuit of the modular electric energy meter in any of the aforementioned embodiments, which will not be described in detail here.

Claims

1. A voltage stabilizing circuit for a modular electric energy meter, characterized in that: include: A detection end, a virtual load and a switch device are used to detect the plugging and unplugging status of the electric energy meter management module; the detection end is used to control the conduction of the switch device when the management module is unplugged, and the switch device and the virtual load are connected in series at both ends of the main voltage.

2. The voltage stabilizing circuit for a modular electric energy meter according to claim 1, characterized in that: The detection end outputs a high level when the management module is unplugged, the switching device is an NPN transistor, the virtual load is connected in series between the positive pole of the power supply and the collector of the NPN transistor, the emitter of the NPN transistor is grounded, and the detection end is connected to the base of the NPN transistor.

3. The voltage stabilizing circuit for a modular electric energy meter according to claim 2, characterized in that: The detection end is also connected to the positive pole of the power supply through a pull-up resistor; when the management module is inserted into the electric energy meter, the detection end level is pulled down, and when the management module is pulled out, the detection end level is pulled up through the pull-up resistor.

4. The voltage stabilizing circuit for a modular electric energy meter according to claim 3, characterized in that: A current limiting resistor is also connected between the detection end and the base of the NPN transistor.

5. The voltage stabilizing circuit for modular electric energy meter according to claim 4, characterized in that: The dummy load includes two resistors connected in parallel.

6. A modular electric energy meter, characterized in that: A voltage stabilizing circuit comprising a modular electric energy meter as described in any one of claims 1 to 5.

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