CN115882738A - CT power-taking power supply circuit for distribution network - Google Patents

Abstract

The invention discloses a CT power-taking power supply circuit for a distribution network, and relates to the technical field of power supplies. Two electrodes of the bidirectional thyristor are respectively connected to the output end CTS1 and the output end CTS2 of the CT power-taking mutual inductor, the two electrodes of the bidirectional thyristor are respectively connected with the 1 pin and the 2 pins of the rectifier bridge, the grid electrode of the bidirectional thyristor is connected with the second resistor and the 1 pin of the rectifier bridge, the grid electrode of the bidirectional thyristor is also sequentially connected with the first resistor and the 2 pins of the transient suppression diode and the rectifier bridge, the 3 pins and the 4 pins of the rectifier bridge are respectively connected with the 1 pin and the 2 pins of the power module, the 1 pin and the 2 pins of the power module are respectively connected with the energy storage capacitor and the filter capacitor, the 4 pins of the power module are sequentially connected with the diode and the backup battery is connected with the 2 pins of the power module. According to the invention, the power supply of the power distribution terminal is realized through CT power taking, a safe power supply source is provided for the power distribution terminal under different current conditions, the utilization rate of the CT power taking electric energy is improved, and the application prospect is wide.

Description

CT power-taking power supply circuit for distribution network

Technical Field

The invention relates to the technical field of power supplies, in particular to a CT power supply circuit for a distribution network.

Background

With the advance of distribution network automation construction, most of distribution network equipment of key nodes is automatically transformed, but part of stock equipment cannot be transformed automatically due to condition limitation, and part of the stock equipment is provided with a 10KV voltage transformer, namely, PT installation needs space and has long power failure time, so that the PT cannot be additionally arranged on site to supply power to the equipment. Therefore, the research on the realization of power supply to automatic equipment through a current transformer, namely CT power taking is a big problem needing to be mainly solved for automatic transformation.

At present, CT power taking power supplies of part equipment manufacturers have application cases on the site, but still have more problems, and are mainly reflected in that: (1) The circuit is too simple, no perfect protection measures are provided, and the subsequent automation device is easily damaged; (2) Although the circuit is protected, when the power supply is higher or lower than the working power supply range of the system, the external power supply is disconnected, and the electric energy loss is easily caused.

In order to solve the problems, a novel CT power supply circuit for a distribution network is particularly necessary.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide the CT electricity-taking power supply circuit for the distribution network, which has the advantages of simple structure and reasonable design, realizes power supply to the power distribution terminal through CT electricity taking, protects the electricity utilization safety of the power distribution terminal, effectively improves the utilization rate of the CT electricity-taking electric energy, and is strong in practicability and easy to popularize and use.

In order to achieve the purpose, the invention is realized by the following technical scheme: the utility model provides a CT gets electric power supply circuit for joining in marriage net, including bidirectional thyristor, the first resistance, the second resistance, transient state restraines the diode, the rectifier bridge, energy storage capacitor, filter capacitor, power module, reserve battery and diode, two electrodes of bidirectional thyristor insert CT respectively and get the CTS1 output of electric transformer, the CTS2 output, two electrodes of bidirectional thyristor still link to each other with 1 foot, 2 feet of rectifier bridge respectively, the second resistance is connected to 1 foot of rectifier bridge to bidirectional thyristor's grid, bidirectional thyristor's grid still connects gradually first resistance, transient state restraines diode to 2 feet of rectifier bridge, 3 feet, 4 feet of rectifier bridge link to each other with 1 foot, 2 feet of power module respectively, be connected with energy storage capacitor, filter capacitor between 1 foot, 3 feet of power module and the 2 feet, 4 feet of power module connect gradually the diode, reserve battery to its 2 feet, connect the analog load between 4 feet of power module and 2 feet.

Preferably, the bidirectional high-power silicon controlled rectifier adopts a bidirectional high-power silicon controlled rectifier BTA41-200.

Preferably, the power supply module adopts a wide-range DC-DC power supply module PE-12V-B4.

Preferably, the backup battery adopts a 12V direct current power supply.

The invention has the beneficial effects that: the circuit realizes power supply to the power distribution terminal through CT power taking, meets the requirement of providing a safe power supply for the power distribution terminal under the condition of different currents, protects the power utilization safety of the power distribution terminal, effectively improves the utilization rate of CT power taking electric energy, and has wide application prospect.

Drawings

The invention is described in detail below with reference to the drawings and the detailed description;

fig. 1 is a circuit diagram of the present invention.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.

Referring to fig. 1, the following technical solutions are adopted in the present embodiment: the utility model provides a CT gets electric power supply circuit for joining in marriage net, including bidirectional thyristor T1, first resistance R1, second resistance R2, transient suppression diode TVS1, rectifier bridge B1, energy storage capacitor C1, filter capacitor C2, power module U1, reserve battery BT1 and diode D1, two electrodes of bidirectional thyristor T1 insert CT respectively and get the CTS1 output of electric transformer, CTS2 output, two electrodes of bidirectional thyristor T1 still respectively with rectifier bridge B1's 1 foot, 2 feet link to each other, rectifier bridge B1 is used for the power rectification, the grid of bidirectional thyristor T1 connects second resistance R2 to rectifier bridge B1's 1 foot, bidirectional thyristor T1's grid still connects gradually first resistance R1, transient suppression diode TVS1 to rectifier bridge B1's 2 feet, rectifier bridge B1's 3 feet, 4 feet respectively with power module U1's 1 foot, 2 feet link to each other, power module U1's 1 foot, be connected with energy storage capacitor C1 between 3 feet and 2 feet, filter capacitor C2, power module U1 foot 4 is connected gradually with its load module's 2 foot of RL, its load module BT1 foot to 2 foot.

It is worth noting that the bidirectional high-power silicon controlled rectifier BTA41-200 is adopted as the bidirectional silicon controlled rectifier T1, a high-power TVS tube is adopted as the transient suppression diode TVS1, and the wide-range DC-DC power supply module PE-12V-B4 is adopted as the power supply module U1; the backup battery BT1 adopts a 12V direct current power supply.

The working principle of the specific embodiment is as follows:

(1) When the CT power taking electric energy and the electric energy consumed by the power distribution terminal reach dynamic balance, the rectified voltage is in the normal working range of the power module U1. The voltage obtained by the CTS1 and the CTS2 is rectified by the rectifier bridge B1 and then supplies power to the power module U1, the power module U1 outputs 12V voltage, the diode D1 is in a cut-off state at the moment, and the external power supply supplies power to the system, so that the distribution transformer terminal can stably work.

(2) When the CT power taking electric energy is smaller than the electric energy consumed by the distribution transformer terminal, the system preferentially consumes the electric energy stored in the energy storage capacitor C1. When the voltage at two ends of the energy storage capacitor C1 is lower than the normal working range of the power module U1, the power module U1 enters a standby mode, the backup battery BT1 continuously supplies power, the system normally works, meanwhile, the CT supplies power to continuously charge the energy storage capacitor C1, when the voltage of the energy storage capacitor C1 is increased to the working range of the power module U1, the analog load RL is automatically switched to the power module U1 to supply power, and when the power of the energy storage capacitor C1 is consumed and reduced, the analog load RL is switched to the backup battery BT1 to supply power; the working mode of power supply switching of the backup battery BT1 and the CT is achieved by reciprocating in this way, and therefore the CT is fully utilized to obtain electric energy.

(3) When the CT power taking electric energy is far larger than the electric energy consumed by the distribution transformer terminal, the voltage at the input end of the power module U1 continuously rises along with the continuous accumulation of the electric energy, at the moment, partial circuit of the bidirectional thyristor T1 starts to work, the voltage rectified by the rectifier bridge B1 is limited in the working range of the power module U1, and the power module device is prevented from being damaged due to overhigh voltage.

Taking the bidirectional triode thyristor BTA41-200 as an example, the specific working flow is as follows: when the voltage values of the CTS1 and the CTS2 are set to be Vi1, when the bidirectional thyristor T1 is not conducted, the Vi1 is applied to two ends of the transient suppression diode TVS1, when the Vi1 is larger than the maximum protection voltage of the transient suppression diode TVS1, the transient suppression diode TVS1 is instantly conducted, due to the voltage division relation, a voltage difference is generated between an anode A1 and a grid of the bidirectional thyristor T1, current flows to the grid through the anode A1, when the current is larger than the opening current of the bidirectional thyristor T1, the bidirectional thyristor T1 is conducted, namely the CTS1 and the CTS2 are in short circuit, and redundant electric energy can be discharged; when the voltage of the CT power-taking input is reduced, the bidirectional controllable silicon T1 is disconnected again. It can be known that when the bidirectional thyristor T1 works in quadrants i and iii, the conduction current Igt of the thyristor is less than 50mA, and the conduction voltage Vgt is less than 1.3V, the conduction voltage Vdt = Vtvs + Igt × R2 of the thyristor.

This embodiment is arranged in no PT power supply and need carry out the distribution network of automatic transformation, use CT to turn into voltage signal with the circuit electric current in joining in marriage the net, get the electricity realization through CT and supply power to distribution terminal, this circuit is through the project organization of excessive pressure release circuit, satisfy under the different current circumstances, provide safe power supply for distribution terminal, distribution terminal's power consumption safety has been protected, guarantee distribution terminal's normal operating, effectively improve CT simultaneously and get the utilization ratio of electric energy, automatic transformation of distribution network has very big practical value under the no power supply condition, possess wide market perspective.

The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (4)

1. The utility model provides a CT for joining in marriage net gets electric power supply circuit, a serial communication port, including bidirectional thyristor (T1), first resistance (R1), second resistance (R2), transient state suppression diode (TVS 1), rectifier bridge (B1), energy storage capacitor (C1), filter capacitor (C2), power module (U1), backup battery (BT 1) and diode (D1), two electrodes of bidirectional thyristor (T1) insert the CTS1 output of CT and get electric transformer respectively, CTS2 output, two electrodes of bidirectional thyristor (T1) still respectively with rectifier bridge (B1) 1 foot, 2 feet link to each other, the second resistance (R2) is connected to rectifier bridge (B1) foot to the grid of bidirectional thyristor (T1), the grid of bidirectional thyristor (T1) still connects gradually first resistance (R1), 2 feet of transient state suppression diode (TVS 1) to rectifier bridge (B1), 3 feet of rectifier bridge (B1), 4 feet respectively with power module (U1 foot, 2 feet link to each other, the power module (RL 1) foot of transient state suppression diode (U1), the load module (RL 2) is connected with its load module (RL 2), the load module (RL 2) foot is connected with its load module (RL 2) respectively, the power module (U1 foot, the load module (RL 2) is connected with the power module (RL 2).

2. The CT power-taking power supply circuit for the distribution network according to claim 1, wherein the bidirectional thyristor (T1) adopts a bidirectional high-power thyristor BTA41-200.

3. The CT power-taking power supply circuit for the distribution network according to claim 1, wherein the power supply module (U1) adopts a wide-range DC-DC power supply module PE-12V-B4.

4. The CT power supply circuit for the distribution network according to claim 1, wherein the backup battery (BT 1) adopts a 12V DC power supply.

Images