阅读说明：本技术 一种电能表中适用于通讯模块的功率电路工作方法 (Power circuit working method applicable to communication module in electric energy meter ) 是由 寿寅生 贺民 章恩友 蒋卫平 马益平 刘照飞 贺东 姚晓峰 郭巨锋 陈亮 盛旭朝 于 2021-07-19 设计创作，主要内容包括：本发明涉及一种电能表中适用于通讯模块的功率电路工作方法,功率电路输入端为交流电,输入端连接一RC串联电路,RC串联电路连接整流二极管,整流二极管一路连接DC/DC转换器,DC/DC转换器输出端给负载供电,整流二极管另一路连接第一稳压二极管,第一稳压二极管再串联连接一第二稳压二极管,第二稳压二极管并联连接一三极管,三极管的基极连接MCU控制器。当通讯模块接收数据时,电路工作在正常状态,MCU控制三极管处于导通状态,通讯模块发送数据时,MCU控制三极管处于截止状态,第二稳压二极管起稳压作用,DC/DC转换器的输入端电压被拉升。本发明通过对电路结构以及电路工作方法的改进,实现了RC电路满足通讯模块的工作要求,并且尽量减少电能损耗。(The invention relates to a power circuit working method suitable for a communication module in an electric energy meter, wherein the input end of a power circuit is alternating current, the input end of the power circuit is connected with an RC series circuit, the RC series circuit is connected with a rectifier diode, one path of the rectifier diode is connected with a DC/DC converter, the output end of the DC/DC converter supplies power to a load, the other path of the rectifier diode is connected with a first voltage-stabilizing diode, the first voltage-stabilizing diode is connected with a second voltage-stabilizing diode in series, the second voltage-stabilizing diode is connected with a triode in parallel, and the base electrode of the triode is connected with an MCU controller. When the communication module receives data, the circuit works in a normal state, the MCU controls the triode to be in a conducting state, when the communication module sends data, the MCU controls the triode to be in a stopping state, the second voltage stabilizing diode plays a role in stabilizing voltage, and the voltage of the input end of the DC/DC converter is pulled up. The invention realizes that the RC circuit meets the working requirement of the communication module and reduces the electric energy loss as much as possible by improving the circuit structure and the circuit working method.)

1. A working method of a power circuit suitable for a communication module in an electric energy meter is characterized in that:

the power circuit power input is alternating current, the power input end comprises a first input end and a second input end, the first input end is connected with an RC series circuit, the output end of the RC series circuit is connected with the anode of a rectifier diode, one path of the cathode of the rectifier diode is connected with a DC/DC converter, the output end of the DC/DC converter supplies power to a communication module, the other path of the cathode of the rectifier diode is connected with the cathode of a first voltage-stabilizing diode, the anode of the first voltage-stabilizing diode is connected with the cathode of a second voltage-stabilizing diode in series, the anode of the second voltage-stabilizing diode is connected with the second input end, the second voltage-stabilizing diode is connected with a triode in parallel, the collector of the triode is connected with the cathode of the second voltage-stabilizing diode, the emitter of the triode is connected with the anode of the second voltage-stabilizing diode, and the base of the triode is connected with an MCU controller;

when the communication module receives data, the circuit works in a normal state, the MCU controller controls the triode to be in a conducting state, the second voltage stabilizing diode is short-circuited by the triode, only the first voltage stabilizing diode plays a voltage stabilizing role, the MCU controller judges whether the data needs to be replied or not, when the data does not need to be replied, the circuit is kept in the normal state, when the data needs to be replied, the MCU controller controls the triode to be in a cut-off state, the second voltage stabilizing diode plays a voltage stabilizing role, the voltage of the input end of the DC/DC converter is pulled up, the output power of the output end of the DC/DC converter is pulled up, the communication module sends data, when the data sending of the communication module is finished, the MCU controller controls the triode to be conducted again, and the circuit is subjected to voltage reduction and reverts to the normal working state.

2. The method of claim 1, wherein the power circuit of the power meter is adapted to the communication module, and the method comprises: and a diode is also connected between the output end of the RC series circuit and the power supply input, the anode of the diode is connected with the second input end, and the cathode of the diode is connected with the output end of the RC series circuit.

3. The method of claim 2, wherein the power circuit of the power meter is adapted to the communication module, and the method comprises: the power supply input is 127V/60HZ alternating current, the stable voltage of the first voltage stabilizing diode is 10V, and the stable voltage of the second voltage stabilizing diode is 20V.

Technical Field

The present invention relates to an improvement in on-load power circuits.

Background

In the electric energy meter, an on-load power circuit is mainly subjected to voltage reduction through a transformer and then rectified to provide direct current. The transformer has loss, and after 1.3 times of input voltage, the loss can be greatly increased, the temperature rise is greatly increased, and a protector is generally required to be added outside. The power consumption of the RC voltage-reducing circuit is very small, but the output current and the output power of the existing RC voltage-reducing loaded power circuit are fixed. For the communication module, the requirements for current and power are different when receiving signals and transmitting signals, the requirements for current and power are low when receiving signals, and the requirements for current and power are high when transmitting signals, so that the requirements of the communication module cannot be completely met by a common RC (resistance-capacitance) voltage-reducing on-load power circuit. If the on-load power is too high, power loss is wasted when receiving signals, and if the on-load power is too low, the power loss is insufficient when transmitting signals.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides a working method which is suitable for a communication module after an on-load power circuit is improved in an electric energy meter.

The invention is realized by the following technical scheme:

a power circuit working method suitable for a communication module in an electric energy meter is characterized in that the power input end of the power circuit is alternating current, the power input end comprises a first input end and a second input end, the first input end is connected with an RC series circuit, the output end of the RC series circuit is connected with the anode of a rectifier diode, one path of the cathode of the rectifier diode is connected with a DC/DC converter, the output end of the DC/DC converter supplies power to the communication module, the other path of the cathode of the rectifier diode is connected with the cathode of a first voltage-stabilizing diode, the anode of the first voltage-stabilizing diode is connected with the cathode of a second voltage-stabilizing diode in series, the anode of the second voltage-stabilizing diode is connected with the second input end, the second voltage-stabilizing diode is connected with a triode in parallel, the collector of the triode is connected with the cathode of the second voltage-stabilizing diode, and the emitter of the triode is connected with the anode of the second voltage-stabilizing diode, the base electrode of the triode is connected with the MCU controller;

when the communication module receives data, the circuit works in a normal state, the MCU controller controls the triode to be in a conducting state, the second voltage stabilizing diode is short-circuited by the triode, only the first voltage stabilizing diode plays a voltage stabilizing role, the MCU controller judges whether the data needs to be replied or not, when the data does not need to be replied, the circuit is kept in the normal state, when the data needs to be replied, the MCU controller controls the triode to be in a cut-off state, the second voltage stabilizing diode plays a voltage stabilizing role, the voltage of the input end of the DC/DC converter is pulled up, the output power of the output end of the DC/DC converter is pulled up, the communication module sends data, when the data sending of the communication module is finished, the MCU controller controls the triode to be conducted again, and the circuit is subjected to voltage reduction and reverts to the normal working state.

Preferably, a diode is further connected between the output end of the RC series circuit and the power input, an anode of the diode is connected to the second input end, and a cathode of the diode is connected to the output end of the RC series circuit.

Preferably, the power supply input is 127V/60HZ alternating current, the stable voltage of the first voltage stabilizing diode is 10V, and the stable voltage of the second voltage stabilizing diode is 20V.

In the application, the resistance-capacitance voltage reduction is realized through the RC series circuit, and the circuit is improved according to the working characteristics of the communication module. An operating characteristic of the communication module that requires less operating current and power when receiving a signal than when transmitting a signal. For example, when the LORA module receives a signal, the working current is 14mA, the required power is 46mW, the circuit can completely meet the requirement in a normal working state, and when the LORA module sends a signal, the working current is 140mA, the required power is 462mW, and the circuit needs to be boosted to meet the requirement. The specific implementation mode is that a voltage stabilizing diode is arranged at the input end of the DC/DC converter, the voltage stabilizing diode is not only provided with a first voltage stabilizing diode, but also is connected with a second voltage stabilizing diode in series, the second voltage stabilizing diode is connected with a triode in parallel, and whether the voltage stabilizing effect is realized by the second voltage stabilizing diode is controlled through the switching action of the triode. When the communication module receives data, the second voltage stabilizing diode is short-circuited by the triode and does not work, the circuit is in a normal working state, when the communication module sends data, the triode is cut off, the second voltage stabilizing diode can be used for pulling up the voltage of the input end of the DC/DC converter, and the requirement of the communication module can be completely met.

The switching function of the triode on or off is controlled by the MCU controller, when the communication module receives data, the MCU controller controls the triode to be in the on state, the circuit is in the normal working state, the MCU controller judges whether the data needs to be replied, when the data needs to be replied, the triode is controlled to be in the off state, and the second voltage stabilizing diode boosts the voltage of the input end of the DC/DC converter to improve the output power.

The invention has the beneficial effects that: the invention realizes that the RC circuit meets the working requirement of the communication module and reduces the electric energy loss as much as possible by improving the circuit structure and the circuit working method.

Drawings

Fig. 1 is a schematic diagram of the circuit structure of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

As shown in fig. 1, in an electric energy meter, a power circuit working method suitable for a communication module is provided, a power supply input of the power circuit is a 127V/60HZ alternating current, a power supply input end includes a first input end and a second input end, the first input end is connected with an RC series circuit, an output end of the RC series circuit is connected with an anode of a rectifier diode D, one way of a cathode of the rectifier diode D is connected with a DC/DC converter, and an output end of the DC/DC converter supplies power to the communication module. The other path of the cathode of the rectifier diode D is connected with the cathode of the first voltage-stabilizing diode D1, the anode of the first voltage-stabilizing diode D1 is connected with the cathode of the second voltage-stabilizing diode D2 in series, and the anode of the second voltage-stabilizing diode D2 is connected with the second input end. The second voltage-stabilizing diode D2 is connected in parallel with the triode Q, the collector of the triode Q is connected with the cathode of the second voltage-stabilizing diode D2, the emitter of the triode Q is connected with the anode of the second voltage-stabilizing diode D2, the base of the triode is connected with the output end of the MCU controller, and the triode Q is equivalent to a switch and is controlled by the MCU controller. And a diode D3 is also connected between the output end and the second input end of the RC series circuit, the anode of the diode D3 is connected with the second input end, and the cathode of the diode D3 is connected with the output end of the RC series circuit.

In this embodiment, taking the LORA module as an example, when receiving data, the required current is 14mA and the required power is 0.046W in the module receiving state, and when sending data, that is, when the module is in the module transmitting state, the required current is 140mA and the required power is 0.462W.

127V/60HZ alternating current is input to the power supply input end, and resistance-capacitance voltage reduction is carried out through an RC series circuit. In the positive half cycle, the voltage is converted into direct current through a rectifier diode D, and is stabilized through a voltage stabilizing diode. In an RC series circuit, the current-limiting capacitor C is 1uF (330V), the capacitive reactance is equal to 1/2 pi fC, and the capacitance of 1uF is equal to about 2.65k under the condition of 60 Hz. The stabilized voltage of the first zener diode is 10V, and the stabilized voltage of the second zener diode is 20V. Here, only half-wave rectification is performed because there is only one rectifying diode. In the environment of input 127V/60HZ, full wave can provide current of 47.8mA, while half wave actually uses current of 23.9 mA. During the negative half cycle, the current passes through the diode D3 and forms a closed loop with the RC series circuit, so that during the negative half cycle the following circuit is protected from negative voltage. When the communication module receives data, the power circuit works normally, the MCU controller outputs high level to control the conduction of the triode Q, the triode Q is equivalent to a switch, the second voltage stabilizing diode D2 is short-circuited by the triode Q, the voltage of the input end of the DC/DC converter is stabilized at 10V, and the output power is 0.239W. When the communication module receives data, the MCU controller judges whether to reply or not, and if not, the circuit is maintained in a normal working state. If the reply is needed, the MCU controller outputs low level to control the triode Q to be cut off, the second voltage stabilizing diode D2 also plays a role of voltage stabilization, the voltage of the input end of the DC/DC converter is pulled up to 30V, the output power of the output end of the DC/DC converter is pulled up to 0.717W, and the communication module sends data. When the data transmission of the communication module is finished, the MCU controls the conduction of the triode Q, and the circuit reduces the voltage and returns to the normal working state.

When the LOW communication module receives data, the required current is 14mA, the required power is 0.046W, and then the circuit can provide 0.239W when in a receiving state, thereby completely meeting the requirement. When the communication module sends data, namely the module is in a transmitting state, the required current is 140mA, the required power is 0.462W, the circuit cannot meet the requirement in a normal working state, but 0.717W can be provided after the voltage is controlled to be pulled up by the MCU controller, and the circuit completely meets the requirement.

The existing transformer circuit has large power consumption and generally needs an external protector. While the power consumption of the general RC circuit is reduced, the RC circuit can not meet the requirements when a LORA communication module is adopted, and the electric energy loss can be greatly increased if the load power is simply increased. Therefore, in the application, RC resistance-capacitance voltage reduction is mainly adopted, and then an RC circuit is improved. The method is mainly based on the working characteristics of the communication module, and when the communication module receives signals, the required current and the required power are smaller than those when the communication module sends signals. The specific implementation mode is that a first voltage-stabilizing diode D1 and a second voltage-stabilizing diode D2 which are connected in series are arranged at the output end of a rectifier diode D, the second voltage-stabilizing diode D2 is connected with a triode Q in parallel, the triode Q is used for controlling whether the second voltage-stabilizing diode D2 realizes a voltage-stabilizing effect, the conduction or the cut-off of the triode Q is controlled by an MCU controller, and the MCU controller is used for controlling according to the fact that a communication module receives data or sends data.

The specific working process is as follows: the circuit only has half-wave rectification, 127V/60HZ alternating current is input to the power input end, and resistance-capacitance voltage reduction is carried out through an RC series circuit. In the positive half cycle, the alternating current is converted into direct current through a rectifier diode D, and is stabilized by a voltage stabilizing diode. During the negative half cycle, the alternating current passes through the diode D3 and forms a closed loop with the RC series circuit, so that during the negative half cycle, the following circuit is protected from the negative voltage.

The input end of the DC/DC converter is direct current, and the voltage of the input end of the DC/DC converter is controlled by a first voltage stabilizing diode D1 and a second voltage stabilizing diode D2. When the communication module receives data, namely the module is in a receiving state, the MCU controller controls the conduction of the triode Q, the second voltage stabilizing diode D2 is short-circuited by the triode Q and does not work, only the first voltage stabilizing diode D1 works, the circuit is in a normal working state, the voltage of the input end of the DC/DC converter is stabilized at 10V, and the power is 0.239W. Then the MCU controller judges whether the recovery is needed or not, and if the recovery is not needed, the MCU controller is kept in the normal working state. If the reply is needed, the MCU controller controls the triode Q to be cut off, the second voltage stabilizing diode D2 works, the voltage of the input end of the DC/DC converter is stabilized at 30V, the power is 0.717W, and the communication module sends data, namely the module is in a transmitting state. The second zener diode D2 can pull up the voltage at the input terminal of the DC/DC converter, and can completely meet the requirement of the communication module during transmission.

The RC resistance-capacitance voltage reduction circuit replaces the existing transformer, so that the loss can be reduced, the stable voltage can be adjusted according to the working state of the communication module through the arrangement of the second voltage stabilizing diode, the output power is adjusted, and the diode D and the back end circuit are protected through the diode D3. Through the mode, the requirements of working current and power of the communication module are met, the working characteristics of the communication module are utilized, the working voltage is only boosted when the communication module sends signals, the loaded power of the power circuit is improved through the second voltage stabilizing diode, and the electric energy loss caused by simply increasing the loaded power is avoided being greatly increased.