Standby power supply switching-in scheme for intelligent measurement terminal

Abstract

The utility model discloses a standby power supply switching scheme for an intelligent measurement terminal, which comprises two main power supply lines, namely a mains supply line and an auxiliary power supply line, and adopts an input lightning protection circuit, a rectification circuit and a filter circuit, so that the terminal has more reliable and stable power supply input. Most importantly, power failure detection of the terminal is realized by using the voltage monitoring chip, a power failure interruption signal is generated and transmitted to the micro-control chip, the standby power supply is started through the micro-control chip, seamless switching between the main power supply and the standby power supply is realized, the terminal is ensured to continuously and normally work when the main power supply is in power failure, and accidental loss of data is prevented.

Description

Technical Field

[0001] The utility model relates to the technical field of power distribution network automation, and in particular to a backup power supply cut-in solution for an intelligent measuring terminal. Background Art

[0002] The intelligent measuring terminal is a new type of measuring equipment in the power system. It can measure and record the use of electric energy in real time and accurately, and transmit this information to the data center through the communication network. In the field of power distribution and utilization, the application of intelligent measuring terminals has become an important trend. It plays a vital role in the field of power distribution and utilization. It is a key device connecting the smart meter and the main station for power consumption information collection. It is usually installed next to the transformer to collect data from the smart meter and perform task scheduling in the power supply area. With the advancement of technology, modern intelligent measuring terminals not only have basic power collection functions, such as realizing the collection and calculation of electrical quantities of large user branch lines and main incoming lines, but also can collect state quantities, such as switch status, energy storage, locking and other signals. In addition, it also supports parameter configuration, such as the specified configuration function of the bus voltage to which the line power calculation belongs, the matrix configuration function of the tripping outlet, and the custom line total power calculation function, to ensure the flexibility of on-site engineering configuration. In order to ensure that when the main power supply has problems or needs maintenance, the intelligent measuring terminal can switch to the backup power supply in time and automatically, ensure continuous and stable power supply, and report the problem to the main station through the backup power supply in time when there is a problem with the main power supply, so as to avoid power outages or unnecessary losses to the power grid system caused by abnormal main power supply. Therefore, a backup power supply solution that can be switched in time is urgently needed. Utility Model Content

[0003] The utility model aims at the shortcomings and defects of the prior art and provides a backup power supply cut-in solution for the intelligent measuring terminal, thereby solving the problem of restarting the intelligent measuring terminal when there is a sudden power outage or the main power is disturbed and abnormal occurs.

[0004] The purpose of the utility model can be achieved through the following technical solutions:

[0005] A backup power supply cut-in solution for an intelligent measurement terminal, characterized by comprising a mains power supply system, an auxiliary power supply system and a backup power supply cut-in control system.

[0006] Furthermore, the power supply system is connected to the intelligent measurement terminal from the mains power, and after passing through the input lightning protection, rectification, and filtering modules, it passes through the AC-DC module to convert the mains power into a 12V power supply that can be used for the mainboard of the intelligent measurement terminal, and can power different functional circuits of the intelligent measurement terminal. The 12V power supply is grounded through two series resistors R1 and R2, R2 is connected in parallel with a capacitor C1, and the far end of R2 is LVD-Z, which is connected to the microcontroller chip; and the 12V power supply is connected to the resistor R6 of the backup power supply cut-in control system.

[0007] Furthermore, the auxiliary power supply system is connected to the intelligent measurement terminal by the auxiliary power supply, and after the input rectification and filtering module, the auxiliary power supply is converted into a 12V power supply that can be used for the mainboard of the intelligent measurement terminal through the AC-DC module, which can power different functional circuits of the intelligent measurement terminal. The 12V power supply is grounded through two series resistors R3 and R4, R4 is connected in parallel with a capacitor C4, and the far end of R4 is LVD-FZ, which is connected to the microcontroller chip; and the 12V power supply is connected to the resistor R6 of the backup power supply cut-in control system.

[0008] Furthermore, the backup power supply cut-in control system is a backup power supply, a microcontroller chip, a voltage detection chip N1, and resistors (R5, R6, R7), and capacitors (C2, C3) connected thereto. One end of R5 and C2 is connected in parallel to the 2-pin Vdd of the N1 chip, and the other end of R5 and C2 is connected in parallel to the ground; one end of R6 is connected to the 2-pin Vdd of the chip N1, and the other end is connected to the 12V power supply of the intelligent measurement terminal. The 1-pin Vout of the chip N1 is connected to the microcontroller chip, and a pull-up resistor R7 and a filter capacitor C3 are connected to ground.

[0009] Furthermore, the 12V power converted by the mains power supply system and the auxiliary power supply system is transformed by the DC-DC module to charge the backup power supply and power the microcontroller chip, and can also provide power for different functional circuits of the terminal.

[0010] Furthermore, for the AC power supply system and the backup power supply system, when the AC power is supplied alone, the microcontroller chip can collect the LVD-Z voltage of the AC power through a voltage sampling resistor, confirm that it is supplied by the AC power, and judge whether the main power supply is normal based on the collected voltage; when the auxiliary power supply is supplied alone, the microcontroller chip can also collect the LVD-FZ voltage of the auxiliary power supply through another voltage sampling resistor, confirm that it is supplied by the auxiliary power supply, and judge whether the auxiliary power supply is normal based on the collected voltage, and at the same time, only one main power (consisting of the AC power and the auxiliary power supply) can be used for power supply.

[0011] Furthermore, the backup power supply is cut into the control system. When the voltage of the main power drops to the set threshold after passing through the lightning protection rectification, filtering circuit and AC-DC circuit, the PWR-DET level changes from high to low level, and a power-off interrupt signal is sent to the microcontroller chip. The microcontroller chip controls the switching of the backup power supply to achieve seamless switching of the backup power supply.

[0012] The beneficial effects of the utility model are:

[0013] 1. This voltage detection chip can reasonably set the required voltage according to demand, which is more flexible;

[0014] 2. The main power can be seamlessly switched to the backup power supply without affecting the normal operation of the terminal;

[0015] 3. The use of lightning protection, rectification and filtering circuits can provide the terminal with a stable, large-load power supply. Setting a reasonable main power-off threshold can avoid the impact of voltage fluctuations caused by spatial electromagnetic interference on the terminal's switching to the backup power supply function;

[0016] 4. There is no need for the terminal to always detect the voltage of the main power supply. Only one interrupt signal is needed to achieve seamless switching of the backup power supply, which occupies very little CPU resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram illustrating the scheme of the utility model.

[0018] Figure symbols: N1 is a voltage detection chip, R1, R2, R3, R4, R5, R6, R7 are resistors, C1, C2, C3, C4 are capacitors. LVD-Z is a mains detection, which can detect the main power voltage according to the program setting, and can charge the backup power supply when the mains is powered; LVD-FZ is an auxiliary power detection, which can detect the auxiliary power voltage according to the program setting. PER-DET is the interrupt signal sent by the voltage detection chip to the microcontroller chip. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model, and do not limit the utility model.

[0020] like Figure 1 As shown, a backup power supply cut-in solution for an intelligent measuring terminal includes a mains power supply system, an auxiliary power supply system and a backup power supply cut-in control system.

[0021] The mains power supply system is connected to the intelligent measurement terminal by the mains power supply. After the input lightning protection, rectification and filtering modules, the AC-DC module converts the mains power into a 12V power supply that can be used for the mainboard of the intelligent measurement terminal, which can power different functional circuits of the intelligent measurement terminal. The 12V power supply is grounded through two series resistors R1 and R2, R2 is connected in parallel with a capacitor C1, and the far end of R2 is LVD-Z, which is connected to the microcontroller chip; and the 12V power supply is connected to the resistor R6 of the backup power supply cut-in control system.

[0022] The auxiliary power supply system is connected to the intelligent measurement terminal by the auxiliary power supply. After the input rectification and filtering module, the auxiliary power is converted into a 12V power supply that can be used for the mainboard of the intelligent measurement terminal through the AC-DC module, which can power different functional circuits of the intelligent measurement terminal. The 12V power supply is grounded through two series resistors R3 and R4, and R4 is connected in parallel with a capacitor C4. The far end of R4 is LVD-FZ, which is connected to the microcontroller chip; and the 12V power supply is connected to the resistor R6 of the backup power supply cut-in control system.

[0023] The backup power supply cut-in control system is a backup power supply, a microcontroller chip, a voltage detection chip N1, and the resistors (R5, R6, R7), and capacitors (C2, C3) connected to it. One end of R5 and C2 is connected in parallel to the 2-pin Vdd of the N1 chip, and the other end of R5 and C2 is connected in parallel to the ground; one end of R6 is connected to the 2-pin Vdd of the chip N1, and the other end is connected to the 12V power supply of the intelligent measurement terminal. The 1-pin Vout of the chip N1 is connected to the microcontroller chip, and a pull-up resistor R7 and a filter capacitor C3 are connected to ground.

[0024] The 12V power converted from the mains power supply system and the auxiliary power supply system is transformed by the DC-DC module to charge the backup power supply and power the microcontroller chip. It can also provide power for different functional circuits of the terminal.

[0025] Mains power supply system and backup power supply system, when the mains power is supplied alone, the microcontroller chip can collect the LVD-Z voltage of the mains power through the voltage sampling resistor, confirm that it is mains power supply, and judge whether the main power supply is normal according to the collected voltage; when the auxiliary power supply is supplied alone, the microcontroller chip can also collect the LVD-FZ voltage of the auxiliary power supply through another voltage sampling resistor, confirm that it is auxiliary power supply, and judge whether the auxiliary power supply is normal according to the collected voltage, and at the same time only one main power (consisting of the mains power and the auxiliary power supply) can be used for power supply.

[0026] The backup power supply cuts into the control system. When the voltage of the main power drops to the set threshold after passing through the lightning protection rectification, filtering circuit and AC-DC circuit, the PWR-DET level changes from high to low, and a power-off interrupt signal is sent to the microcontroller chip. The microcontroller chip controls the switching of the backup power supply to achieve seamless switching of the backup power supply.

[0027] Based on the above scheme, the basic working principle of the utility model is as follows:

[0028] Taking the mains power supply as an example, the voltage after passing through the AC-DC module is V i , V i After passing through the DC-DC module, the voltage is reduced to power the microcontroller chip and some functional circuits of the intelligent measurement terminal. i It will not drop to 0V immediately, but will gradually drop to 0V over a certain period of time. The voltage detection chip also detects V i Voltage, when the voltage drops to the set value V within 10ms s When the power is off, PWR-DET changes from high level to low level, and sends the interrupt signal of the main power failure to the microcontroller chip. The microcontroller chip issues a command to start the backup power supply to ensure that the terminal can continue to operate when the main power is off. The set value V can be adjusted by resistors R5 and R6. s , assuming that the voltage at pin 2 of the N1 chip is V2, the calculation formula is as follows:

[0029] V2=V s (R5 / (R5+R6))

[0030] Although the LVD-Z voltage and LVD-FZ voltage can be detected in real time by the microcontroller chip to determine whether the main power is normal, and the backup power supply can be started when the main power is abnormal, if you want to start the backup power supply in time when the main power is not completely interrupted, you need to detect the LVD-Z voltage and LVD-FZ voltage every less than 10ms, which will greatly occupy CPU resources. The backup power supply cut-in solution for intelligent measurement terminals can reduce a large amount of CPU resource usage.

[0031] From the perspective of providing power for the intelligent measurement terminal, this solution provides the intelligent measurement terminal with three power supply modes: AC power, auxiliary power supply, and backup power supply. This greatly ensures the continuous and stable operation of the terminal's power supply system under complex environmental conditions. In addition, when a sudden power outage or external environmental interference causes the main power to fail, it can also switch to the backup power supply in time and report the relevant power outage information to the main station, so that the power grid staff can locate the problem in a timely and accurate manner.

[0032] The above embodiments are descriptions of specific implementation methods of the present invention, rather than limitations of the present invention. Technicians in the relevant technical field may make various changes and modifications to obtain corresponding equivalent technical solutions without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions should be included in the patent protection scope of the present invention.

Claims

1. A backup power supply cut-in solution for an intelligent measurement terminal, characterized in that: It includes a mains power supply system, an auxiliary power supply system and a backup power supply cut-in control system; the mains power supply system is connected to the intelligent measurement terminal by the mains power, and after passing through the input lightning protection, rectification and filtering modules, it passes through the AC-DC module to convert the mains power into a 12V power supply that can be used for the mainboard of the intelligent measurement terminal, which can power different functional circuits of the intelligent measurement terminal, and the 12V power supply is grounded through two series resistors R1 and R2, R2 is connected in parallel with a capacitor C1, and the remote end of R2 is LVD-Z, which is connected to the microcontroller chip; and the 12V power supply is connected to the resistor R6 of the backup power supply cut-in control system; the auxiliary power supply system is connected to the intelligent measurement terminal by the auxiliary power supply, and after passing through the input rectification and filtering modules, it passes through the AC-DC module to convert the auxiliary power supply into a 12V power supply that can be used for the mainboard of the intelligent measurement terminal, which can power the intelligent measurement terminal The 12V power supply is connected to the ground through two series resistors R3 and R4, and a capacitor C4 is connected in parallel to R4. The remote end of R4 is LVD-FZ, which is connected to the microcontroller chip; and the 12V power supply is connected to the resistor R6 of the backup power supply cut-in control system; the backup power supply cut-in control system is the backup power supply, the microcontroller chip and the voltage detection chip N1 and the resistors (R5, R6, R7) and capacitors (C2, C3) connected thereto, wherein one end of R5 and C2 are connected in parallel to the 2-pin Vdd of the N1 chip, and the other end of R5 and C2 are connected in parallel to the ground; one end of R6 is connected to the 2-pin Vdd of the chip N1, and the other end is connected to the 12V power supply of the intelligent measurement terminal, and the 1-pin Vout of the chip N1 is connected to the microcontroller chip, and a pull-up resistor R7 and a filter capacitor C3 are connected to the ground.

2. A backup power supply cut-in solution for an intelligent measurement terminal according to claim 1, characterized in that: The 12V power converted by the mains power supply system and the auxiliary power supply system is transformed by the DC-DC module to charge the backup power supply and power the microcontroller chip, and can also provide power for different functional circuits of the terminal.

3. A backup power supply cut-in solution for an intelligent measurement terminal according to claim 1, characterized in that: The AC power supply system and the backup power supply system, when the AC power is supplied alone, the microcontroller chip can collect the LVD-Z voltage of the AC power through a voltage sampling resistor, confirm that it is supplied by the AC power, and judge whether the main power supply is normal based on the collected voltage; when the auxiliary power supply is supplied alone, the microcontroller chip can also collect the LVD-FZ voltage of the auxiliary power supply through another voltage sampling resistor, confirm that it is supplied by the auxiliary power supply, and judge whether the auxiliary power supply is normal based on the collected voltage, and only one main power can be supplied at the same time, and the main power is composed of the AC power and the auxiliary power supply.

4. A backup power supply cut-in solution for an intelligent measuring terminal according to claim 1, characterized in that: The backup power supply is cut into the control system. When the voltage of the main power drops to the set threshold after passing through the lightning protection rectification, filtering circuit and AC-DC circuit, the PWR-DET level changes from high to low level, and a power-off interrupt signal is sent to the microcontroller chip. The microcontroller chip controls the switching of the backup power supply to achieve seamless switching of the backup power supply.

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