CN111786389A - A dual power switching device applied to DTU/FTU - Google Patents

Abstract

The invention provides a double-power switching device applied to a DTU/FTU, wherein the input end of the switching device is connected with a power supply input route, the output end of the switching device is connected with the power supply input end of the FTU/DTU, the power supply input route comprises an A route and a B route, and the A route and the B route are respectively connected with mutually independent power supplies; the input end of the switching device is provided with a switching switch, the switching switch is connected with one of the path A or the path B of the power supply input route, and the switching action time of the switching switch is less than the fluctuation time of the output voltage of the set FTU/DTU. The dual-power switching device is additionally arranged on a power supply of the FTU/DTU, so that the normal work of the FTU/DTU is not influenced when the two-way power supply is switched, and the fluctuation time of the output voltage is ensured to be less than a set value; the stability and reliability of power supply can be ensured, and the stability and reliability of the operation of the FTU/DTU are improved; in addition, the device has simple structure and also has the function of power-off warning.

Description

A dual power switching device applied to DTU/FTU

technical field

The invention relates to the field of power supply switching, in particular to a dual power supply switching device applied to DTU/FTU.

Background technique

DTU is the power distribution terminal installed in 10kV power distribution room, switch station, ring network cabinet and other stations, FTU is the power distribution terminal installed on the overhead line column switch, DTU and FTU are provided by voltage transformer (TV) 220V working voltage. Nowadays, people have high requirements for power supply. If the power supply is interrupted in the middle, it will cause great losses. Therefore, people usually choose dual power supply.

In the case of dual power supply, the dual power switching device is a necessary part of the FTU/DTU. A dual power switching device is installed between the two power supplies of A and B and the power input terminal of the FTU/DTU. For the DTU installed at the station end, the two voltage transformers (TV) are powered by two 10kV busbars (A and B) respectively; for the FTU installed on the section and tie switches, the 10kV lines at both ends of the switch (A road and B road) supply power to two voltage transformers (TV) respectively. That is to say, whether it is DTU or FTU, there are usually A and B dual-channel independent external power supplies to provide power supply for the power distribution terminal; and when dual-channel power supply switching is used, it is necessary to ensure that the normal operation of the FTU/DTU is not affected. , in order to meet people's expectations.

Therefore, in view of the above-mentioned requirements, a dual power supply switching device is designed to solve the problem of selection and switching of the A and B power supplies in practical applications. The dual power switching device is set between the two independent external power supplies of A and B and the FTU/DTU power input terminals. On the one hand, the switching device can ensure that the switching can be performed correctly when needed. On the other hand, the switching process must be fast and cannot be Affect the normal work of FTU/DTU. Therefore, a dual power switching device applied to DTU/FTU has great challenges, but it has indeed become an innovative design concept of current technicians.

SUMMARY OF THE INVENTION

In order to overcome the defects of the prior art, the object of the present invention is to provide a dual power supply switching device applied to DTU/FTU, which is aimed at the power supply technology of the DTU installed at the station end and the FTU installed on the segment/tie switch, The problem of selection and switching of dual power supplies in the prior art is solved; that is, when the problem of the power supply route occurs, the selection and switching can be carried out in time, so as to achieve the effect of continuous and uninterrupted power supply of the FTU/DTU.

In view of the above problems, the present invention provides a dual power switching device applied to a DTU/FTU. The input end of the switching device is connected to the power supply input route, and the output end of the switching device is connected to the power input end of the FTU/DTU. The power supply input line includes a circuit A and a circuit B, and the circuit A and the circuit B are respectively connected to mutually independent power supplies; the input end of the switching device is provided with a switch, and the switch is connected to the circuit A or the circuit A of the power supply input route. B way select one connection, and the switching time of the switch is less than the set fluctuation time of the output voltage of the FTU/DTU.

Further, the A channel and the B channel are respectively provided with a K1 relay and a K2 relay, and the switch is a double-pole double-throw switch.

Further, the switching device is provided with a running light, a street light, a street light B and a voltage loss warning light, wherein,

Running light: After the switching device is running, the running light is always on;

A street lamp: switch to A channel power output;

B street light: switch to B channel power output;

Loss of pressure warning light: remote signal indication of pressure loss warning signal.

Further, the double-cutting device is provided with a 485 communication interface, and the 485 communication interface is connected to the DTU/FTU, and the DTU/FTU sets relevant parameters through the 485 communication interface.

Further, the relevant parameters set through the 485 communication interface include voltage stabilization duration and output voltage fluctuation time, wherein,

The voltage stabilization duration: when the voltage value of circuit A returns to the normal range, and the duration exceeds the set time, it switches back to circuit A, and is powered by circuit A;

The output voltage fluctuation time: when the dual power supply is switched, ensure the normal operation of the FTU/DTU, so that the output voltage fluctuation time is less than the set value.

Further, the control circuit of the switching device includes a main control board and a bottom board, the main control board and the bottom board are connected by double-row pins, and the bottom board provides the main control board with the alternate acquisition signals of the A road and the B road and Power supply, the main control board provides relay control signals, alarm control signals and 485 communication signals for the bottom plate.

Further, the main control board collects the power supply voltage information of the A- and B-channels, performs data processing and analysis, controls the corresponding relay action according to the calculation result, and simultaneously lights the corresponding A street lamp or B street lamp to control the dual power supply switching action.

Further, when the switching device performs the switching action, it is necessary to simultaneously judge that the power supply of either the A channel or the B channel loses voltage, and control the output of the alarm signal.

Further, the voltage loss of the power supply means that the voltage is lower than 80% of the rated voltage.

The invention records the beneficial effects brought by the technical solution:

1. The present invention is applied to the occasions where the power supply needs to be automatically switched in the field of power system and industrial control, especially as a necessary accessory of FTU/DTU equipment, it is applied to A and B two independent external power supply and FTU/DTU power supply Between the input terminals, it solves the problem of selection and switching of two power supplies in the case of dual power supply.

2, the present invention can realize the following purposes:

1) Under normal conditions, the working power is provided by one of them;

2) When the power supply of channel A is abnormal, it should automatically switch to channel B, and supply power from channel B;

3) When the voltage value of channel A returns to the normal range, and the duration exceeds the set time, it can automatically switch back to channel A and supply power from channel A;

4) The normal operation of the FTU/DTU is not affected when the dual-circuit power supply is switched, and the fluctuation time of the output voltage is guaranteed to be less than the set value.

3. The dual power switching device of the present invention also has a power loss alarm function, the alarm information is provided to the FTU/DTU remote signaling signal collection through the outgoing node; the current two-way power supply input conditions and voltage loss alarm conditions are displayed through the indicator lights. .

The present invention provides a dual power supply switching device applied to DTU/FTU. Since the DTU/FTU product can support dual power supply, the dual power supply switching device of the present invention can be added to the power supply of the FTU/DTU. Ensure the stability and reliability of the power supply, thereby improving the stability and reliability of the FTU/DTU operation; due to the improvement of the stability and reliability of the DTU/FTU product operation, it also greatly improves the level of power distribution automation. The reliability of power grid operation can play a great role. Moreover, when the dual power supply is switched, it is ensured that the FTU/DTU can maintain a normal working state. The dual power switching device has a simple structure and is convenient for popularization and application.

Description of drawings

1 is a schematic diagram of a switching circuit of the power supply of the device itself in a preferred embodiment of a dual power switching device applied to a DTU/FTU of the present invention.

2 is a schematic diagram of a dual power switching circuit for external output in a preferred embodiment of a dual power switching device applied to a DTU/FTU of the present invention.

FIG. 3 is a schematic diagram of the internal signals of the device in a preferred embodiment of a dual power switching device applied to a DTU/FTU according to the present invention.

4 is a schematic diagram of a main control board circuit in a preferred embodiment of a dual power switching device applied to a DTU/FTU of the present invention.

5 is a schematic diagram of a midplane circuit in a preferred embodiment of a dual power switching device applied to a DTU/FTU of the present invention.

6 is a schematic diagram of a device panel in a preferred embodiment of a dual power switching device applied to a DTU/FTU according to the present invention.

Detailed ways

The embodiment of the present invention provides a dual power supply switching device applied to DTU/FTU, which is used to solve the problem of the existence of synonyms and polysemy in the prior art, which affects the accurate analysis of text information and is prone to analysis deviations. problems, and the above-mentioned problems such as the acquisition of formulas, pictures, and table content information; the general idea of the technical solution provided by the present invention is as follows:

In order to better understand the above technical solutions, the technical solutions of the embodiments of the present specification will be described in detail below through the accompanying drawings and specific embodiments. The detailed description is not intended to limit the technical solutions of the present specification, and the embodiments of the present specification and the technical features in the embodiments may be combined with each other under the condition of no conflict.

1-6 are schematic diagrams of a dual power switching device applied to a DTU/FTU in a preferred embodiment of the present invention.

The present invention provides a dual power supply switching device applied to DTU/FTU, the input end of the switching device is connected to a power supply input line, the output end of the switching device is connected to the power supply input end of the FTU/DTU, and the power supply input line Including A road and B road, and the A road and B road are respectively connected with mutually independent power supply; the input end of the switching device is provided with a switch, and the switch and the A road or B road of the power supply input route are selected. a connection, and the switching time of the switch is less than the set fluctuation time of the output voltage of the FTU/DTU.

The present invention is applied to the occasions where the power supply needs to be switched automatically in the field of electric power system and industrial control, especially as a necessary accessory of FTU/DTU equipment, it is applied to A and B two independent external power supply and FTU/DTU power input terminal In between, to solve the problem of selection and switching of two power supplies in the case of dual power supply.

The following objects can be achieved by adopting the present invention:

1) Under normal conditions, the working power is provided by one of them (such as A road);

2) When the power supply of circuit A is abnormal (such as voltage fluctuation exceeding the normal value range of -20% to +20%, power failure, etc.), it should automatically switch to circuit B and supply power from circuit B;

3) When the voltage value of channel A returns to the normal range, and the duration exceeds the set time (such as 120s), it can automatically switch back to channel A and supply power from channel A;

4) The normal operation of the FTU/DTU is not affected when the dual power supply is switched, and the output voltage fluctuation time is guaranteed to be less than the set value (such as 10ms).

Specifically, the A channel and the B channel are respectively provided with a K1 relay and a K2 relay, and the switch is a double-pole double-throw switch.

As shown in Figure 1, the switching process of the power supply of the device itself:

K is a double-pole double-throw switch, which is separated and closed by the relay control. K is a normally closed switch. As long as the A-circuit power supply (L1, N1) is normal and in a normally closed state, the A-circuit side power supply (L1, N1) of K is turned on. If the power supply of channel A (L1, N1) loses pressure, and the power supply of channel B (L2, N2) is normal, the power supply on the B channel side of K is connected through the relay.

(1) When the power input of channel A (L1, N1) is normal (within the range of plus or minus 20% of AC220V), K1 is closed, the power supply of channel A (L1, N1) is turned on, and the control circuit is powered by the power supply of channel A.

(2) When the power supply of circuit A (L1, N1) loses power or the voltage drops below 80% (176V) of the rated voltage of 220V, the power supply of circuit B (L2, N2) makes the relay absorb K, and the power supply of circuit B (L2, N2) is turned on, and the control circuit is powered by the B-channel power supply.

(3) When the power supply of circuit B (L2, N2) loses power or the voltage drops below 80% (176V) of the rated voltage of 220V, no matter whether the circuit A is normal or not, the K is closed to turn on the circuit A, and the control circuit is powered by the circuit A. powered by.

As shown in Figure 2, the external output dual power switching is completed by the control circuit with CPU:

The control circuit collects the voltages of A and B, and according to the voltages of A and B, the software controls the on and off of DK1 and DK2. DK1 is connected to supply power to A; DK2 is connected to supply power to B. DK1 and DK2 cannot be switched on at the same time. Controlled by the CPU, when switching from one way to another, that is, the time interval between when one relay is turned off to the other when it is turned on cannot exceed 10ms.

The dual power switching device of the present invention also has a power failure alarm function, and the alarm information is provided to the FTU/DTU remote signaling signal collection through the switch-out node;

Specifically, the switching device is provided with a running light, a street light, a street light B and a voltage loss warning light, wherein,

Running light: After the switching device is running, the running light is always on;

A street lamp: switch to A channel power output;

B street light: switch to B channel power output;

Loss of pressure warning light: remote signal indication of pressure loss warning signal.

That is, the device can output alarm information when either of the two power sources of A and B loses voltage (the settable voltage is lower than 80% of the rated voltage). The alarm forms are divided into: lighting the alarm indicator; providing alarm remote signaling output, which can be connected to the DTU/FTU for DTU/FTU collection.

Specifically, the double-cutting device is provided with a 485 communication interface, and the 485 communication interface is connected to the DTU/FTU, and the DTU/FTU sets relevant parameters through the 485 communication interface;

Among them, the relevant parameters set through the 485 communication interface include voltage stabilization duration and output voltage fluctuation time. Specifically,

The voltage stabilization duration: when the voltage value of circuit A returns to the normal range, and the duration exceeds the set time, it switches back to circuit A, and is powered by circuit A;

The output voltage fluctuation time: when the dual power supply is switched, ensure the normal operation of the FTU/DTU, so that the output voltage fluctuation time is less than the set value.

Specifically, as shown in FIG. 3 , the control circuit of the switching device includes a main control board and a backplane, the main control board and the backplane are connected by double-row pins, and the backplane provides A and B for the main control board. The main control board provides relay control signals, alarm control signals and 485 communication signals for the bottom plate.

Among them, as shown in Figure 4, the main control board collects the power supply voltage information of the A and B channels, performs data processing and analysis, controls the corresponding relay actions according to the calculation results, and lights the corresponding A street lamp or B street lamp at the same time, so as to achieve intelligent Control dual power switching action. At the same time, when it is judged that either the power supply of channel A or channel B loses voltage, the output of the alarm signal is controlled; specifically, the voltage of the power supply can be set to be lower than 80% of the rated voltage.

The main control board provides one RS485 communication interface for setting system parameters such as switching time.

As shown in Figure 5, the base plate provides all the external interfaces of the device, so the system power supply, PT sampling circuit, relay and related control circuit, RS485 isolation chip and supporting power supply, and alarm output circuit are all placed on the base plate.

Specifically, a dual power switching device applied to a DTU/FTU provided in this embodiment is designed as a small square box with a size of 115mm*90mm*40mm, as shown in FIG. 6 . The chassis leads out 3 groups of terminals: AC input terminal, AC output terminal and functional terminal. The chassis panel contains 4 indicators: running, pressure loss alarm, L1, L2, as follows:

Running: After the equipment is running, the running light is always on;

Pressure loss alarm: pressure loss alarm signal remote signaling signal indication;

L1: switch to channel A power output (ie U1, U1n power output);

L2: switch to B-channel power output (ie U2, U2n power output).

The relevant technical parameters of the dual power switching device applied to the DTU/FTU in this embodiment are:

Rated voltage Un: 220VAC; normal working range of voltage: (-20%～+20%)Un; contact capacity: 8A@250VAC/30VDC; switching power: ≤1000W; switching time: ≤10ms; insulation resistance: ≥100MΩ; Voltage performance: input to earth: 2500VAC/1minute, leakage current: ≤5mA.

The electromagnetic compatibility performance of the dual power switching device applied to the DTU/FTU in this embodiment is as follows:

Voltage drop and interruption: The sudden drop △U is 100%, and the voltage interruption is 0.5s, and it can work normally;

Electrostatic discharge immunity: level 4, air discharge ±15kV;

Electrical fast transient burst immunity: Class 4, ±4kV;

Damped shock wave immunity: common mode 2.5kV, differential mode 1kV;

Surge immunity: Class 4, ±4kV;

Power frequency magnetic field immunity: continuous magnetic field 100A/m, short-term magnetic field 1000A/m.

In the dual power switching device applied to DTU/FTU in this embodiment, the temperature range of the device is operating temperature: -40°C to +70°C; storage temperature: -40°C to +85°C.

The invention provides a dual power supply switching device applied to DTU/FTU. Since DTU/FTU products can support dual power supply, the dual power supply switching device of the invention is added to the power supply of FTU/DTU. When the power supply is switched, it does not affect the normal operation of the FTU/DTU, and ensures that the output voltage fluctuation time is less than the set value; it can ensure the stability and reliability of the power supply, thereby improving the stability and reliability of the FTU/DTU operation. In addition, the device also has the function of power loss alarm. The alarm information is provided to the FTU/DTU remote signal collection through the outgoing node; the current two-way power supply input status and voltage loss alarm status are displayed through the indicator lights. Due to the improvement of the stability and reliability of the operation of DTU/FTU products, the operation level of distribution automation has also been greatly improved, which can play a great role in improving the reliability of distribution network operation, and is convenient for popularization and application.

While the preferred embodiments of this specification have been described, additional changes and modifications to these embodiments may occur to those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be construed to include the preferred embodiment and all changes and modifications that fall within the scope of this specification.

Obviously, those skilled in the art can make various changes and modifications to this specification without departing from the spirit and scope of this specification. Thus, provided that these modifications and variations of the present specification fall within the scope of the claims of the present specification and technical equivalents thereof, the present specification is also intended to include these modifications and variations.

Claims (9)

1. The utility model provides a be applied to DTU/FTU's dual supply auto-change over device which characterized in that: the input end of the switching device is connected with a power supply input route, the output end of the switching device is connected with the power supply input end of the FTU/DTU, the power supply input route comprises an A path and a B path, and the A path and the B path are respectively connected with mutually independent power supply sources; the input end of the switching device is provided with a switching switch, the switching switch is connected with one of the path A or the path B of the power supply input route, and the switching action time of the switching switch is less than the fluctuation time of the output voltage of the set FTU/DTU.

2. The dual power switching device applied to the DTU/FTU according to claim 1, wherein: the A path and the B path are respectively and correspondingly provided with a K1 relay and a K2 relay, and the change-over switch is a double-pole double-throw switch.

3. The dual power switching device applied to the DTU/FTU according to claim 1 or 2, wherein: the switching device is provided with an operation lamp, a street lamp A, a street lamp B and a decompression warning lamp, wherein,

operating the lamp: after the switching device operates, the operating lamp is normally on;

a street lamp: switching to A-path power output;

and B, street lamp: switching to B power supply output;

pressure loss warning lamp: and indicating the voltage loss alarm signal by a remote signaling signal.

4. The dual power switching device applied to the DTU/FTU according to any one of claims 1 to 3, wherein: this double-cutting device is equipped with 485 communication interface, just 485 communication interface and DTU FTU connect, DTU FTU passes through 485 communication interface and sets up relevant parameter.

5. The dual power switching device applied to the DTU/FTU according to claim 4, wherein: the relevant parameters set via the 485 communication interface include the voltage stabilization duration and the output voltage fluctuation time, wherein,

the voltage stabilization duration is: when the voltage value of the path A is recovered to the normal range and the duration time exceeds the set time, switching back to the path A and supplying power by the path A;

the output voltage fluctuation time: when the two-way power supply is switched, the normal work of the FTU/DTU is ensured, and the fluctuation time of the output voltage of the FTU/DTU is smaller than a set value.

6. The dual power switching device applied to the DTU/FTU according to claim 1, wherein: the control circuit of the switching device comprises a main control board and a bottom board, wherein the main control board is connected with the bottom board through double rows of contact pins, the bottom board provides an A-way and B-way alternate acquisition signal and a power supply for the main control board, and the main control board provides a relay control signal, an alarm control signal and a 485 communication signal for the bottom board.

7. The dual power switching device applied to the DTU/FTU according to claim 6, wherein: the main control board collects the power supply voltage information of the A path and the B path and carries out data processing and analysis, corresponding relay actions are controlled according to the calculation results, the corresponding street lamp A or street lamp B is lightened at the same time, and the dual power supply switching actions are controlled.

8. The dual power switching device applied to the DTU/FTU according to claim 7, wherein: when the switching device performs switching action, the output of an alarm signal is controlled when the voltage loss of any one of the A-path power supply or the B-path power supply needs to be judged at the same time.

9. The dual power switching device applied to the DTU/FTU according to claim 8, wherein: the power supply voltage loss finger voltage is lower than 80% of the rated voltage.

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