CN110868056A - Dynamic switching device for remote control frequency converter - Google Patents

Abstract

The invention discloses a dynamic switching device used for remote control of frequency converters, comprising a PLC controller and a plurality of switching circuits arranged in parallel; The PLC controller includes the input signal module for collecting the required state signal and the output signal module for sending the driving signal; the switching loop is connected to the PLC controller; the switching loop includes the working trunk and Spare/Maintenance Trunk. The invention can be applied to the motor load with long-term operation and high continuity of power supply. The dynamic switching device realizes the function of remote control and dynamic switching of the frequency converter through the PLC controller, so as to achieve the rapid switching of frequency converter failures, avoid the possibility of human operation errors, and effectively The reliability and safety of the dynamic switching device in the power supply system are greatly improved, and the continuity requirements of long-term power supply can be met.

Description

Dynamic switching device for remote control of frequency converters

technical field

The invention belongs to the technical field of power supply of electric power systems, and in particular relates to a dynamic switching device used for remote control of frequency converters.

Background technique

As the drive equipment of the motor load, the inverter needs to be equipped with multiple inverters in order to ensure the long-term continuous operation of the motor and prevent the inverter from malfunctioning during the working process. The coordination command and standby switching of multiple frequency converters need to be undertaken by the switching device, so the switching device undertakes the overall and standby switching operation tasks of the power supply system.

The perfect switching function can solve the fault switching requirements in more complex situations. If a fault occurs, the manual operation of the inverter will take a long time to switch, and the manual operation is prone to errors, which cannot fully guarantee the uninterrupted operation of the power supply system.

SUMMARY OF THE INVENTION

The present invention is proposed in order to overcome the shortcomings of the prior art that the manual operation of frequency converter switching has a long response time and is prone to errors, and aims to provide a dynamic switching device for remote control of frequency converters.

The present invention is achieved through the following technical solutions:

A dynamic switching device for remote control of frequency converters comprises a PLC controller and a plurality of switching circuits arranged in parallel; the input ends of the switching circuits are respectively connected with the output ends of the working frequency converter, the standby frequency converter and the maintenance frequency converter. The output end is connected to the load; the PLC controller includes an input signal module and an output signal module, the input signal module collects required state signals, and the output signal module sends a drive signal; the switching loop is connected to the PLC controller; the switching loop includes The working trunk line and the standby/maintenance trunk line are connected in parallel with each other, the working trunk line includes the isolation switch and the No. 1 circuit contactor in series, the upper port of the isolation switch is connected to the output end of the working frequency converter, and the lower port is connected to the upper port of the No. 1 circuit contactor; The standby/maintenance trunk line includes a series-connected transfer switch and No. Ⅱ loop contactor. The transfer switch has two sets of upper ports, which are respectively connected to the standby inverter and the maintenance inverter, and the lower port is connected to the No. Ⅱ loop contactor; the No. Ⅰ loop contactor The lower port of the circuit contactor and No. Ⅱ are connected to the upper port of the electronic switch assembly, the lower port of the electronic switch assembly is connected to the upper port of the short-circuit contactor and the upper port of the output terminal, and the lower port of the short-circuit contactor is short-circuited, and the lower port of the output terminal is connected. port is connected to the load.

In the above technical solution, the switching loops are divided into three groups.

In the above technical solution, the input signal module is used to collect external control signals, and the external control signals include panel button signals, inverter status signals, loop device status signals, and sensor acquisition parameter signals.

In the above technical solution, the inverter state signal includes a start-up completion signal, a fault signal, and a power failure signal; the loop device includes an isolation switch, a contactor, and a transfer switch; and the sensor includes a voltage sensor and a current sensor.

In the above technical solution, the output signal module sends control signals to the working inverter, the standby inverter, the maintenance inverter and the loop device.

In the above technical solution, the control signal includes a start signal and a stop signal.

In the above technical solution, the loop device includes a loop contactor and a shorting contactor.

In the above technical solution, the output signal module sends the collected parameter data and operation records and fault records to the host computer and the touch screen for display.

The beneficial effects of the present invention are:

The invention provides a dynamic switching device for remote control of frequency converters, which can be applied to motor loads with long-term operation and high continuity of power supply. It can achieve rapid switching of frequency converter failures, avoid the possibility of human operation errors, effectively improve the reliability and safety of dynamic switching devices in the power supply system, and meet the continuity requirements of long-term power supply.

Description of drawings

Fig. 1 is the structure schematic diagram of assembling the power supply system of the present invention;

Fig. 2 is the structural representation of the present invention;

FIG. 3 is a method flow chart of the handover method of the present invention.

in:

1PLC controller 2Switching circuit

3 Working inverter 4 Standby inverter

5 Overhaul the inverter 6 Load

21 isolating switch 22 I circuit contactor

23 transfer switch 24 Ⅱ circuit contactor

25 Electronic switch assembly 26 Shorting contactor

For those of ordinary skill in the art, other related drawings can be obtained from the above drawings without any creative effort.

Detailed ways

In order to make those skilled in the art better understand the technical solution of the present invention, the technical solution of the present invention for the dynamic switching device for remote control of a frequency converter is further described below with reference to the accompanying drawings and specific embodiments.

Example 1

As shown in Figures 1 and 2, a dynamic switching device for remote control of frequency converters includes a PLC controller 1 and multiple groups of switching circuits 2 arranged in parallel; The inverter 4 is connected to the output terminal of the maintenance inverter 5, and its output terminal is connected to the load 6;

The PLC controller 1 includes an input signal module and an output signal module, the input signal module collects required state signals, and the output signal module sends a drive signal;

The switching circuit 2 is connected to the PLC controller 1; the switching circuit 2 includes a working trunk line and a backup/maintenance trunk line in parallel with each other,

Described working trunk line comprises isolating switch 21 and No. 1 loop contactor 22 connected in series, the upper port of isolating switch 21 is connected to the output end of working frequency converter 3, and the bottom port is connected to the upper port of No. 1 loop contactor 22;

The standby/maintenance trunk line includes a series-connected transfer switch 23 and No. II circuit contactor 24. The transfer switch 23 has two sets of upper ports, which are respectively connected to the standby frequency converter 4 and the maintenance frequency converter 5, and its lower port is connected to the No. II circuit contactor. twenty four;

The lower ports of the No. I loop contactor 22 and the No. II loop contactor 24 are connected to the upper port of the electronic switch assembly 25, and the lower port of the electronic switch assembly 25 is connected to the upper port of the shorting contactor 26 and the upper port of the output terminal, and the shorting contactor The lower port of 26 is short-circuited, and the lower port of the output terminal is connected to the load 6.

The switching loops 2 are in three groups.

The input signal module is used to collect external control signals, and the external control signals include panel button signals, inverter status signals, loop device status signals, and sensor acquisition parameter signals.

The inverter status signal includes a start-up completion signal, a fault signal, and a power failure signal; the circuit device includes an isolation switch, a contactor, and a transfer switch; the sensor includes a voltage sensor and a current sensor.

The output signal module sends control signals to the working inverter 3, the standby inverter 4, the maintenance inverter 5 and the loop device.

The control signal includes a start signal and a stop signal.

The loop device includes a loop contactor and a shorting contactor.

The output signal module sends the collected parameter data, operation records, and fault records to the host computer and the touch screen for display.

Example 2

As shown in FIG. 3 , the switching control method of applying the dynamic switching device of the present invention includes the following steps:

I normal working procedure

(I) Initialize S1

start initialization;

(II) Judgment of the state of the isolation switch S2

After initialization, the state of the isolation switch 21 is first detected to judge whether the inverter 3 is ready to be started, the next step is performed in the ON state, and the OFF state is returned;

(III) Proximity control S3

Set the control mode, select close control;

(IV) Fault judgment of working inverter S4

According to the fault signal of the working inverter 3, judge whether the working power supply is faulty, if the working power supply fails, return, and if there is no fault, go to the next step;

(V) Send start signal S5

Send a start signal to the working inverter 3;

(VI) Send the contactor turn-on signal S6

After sending the start signal of the working inverter 3, the No. 1 circuit contactor 22 is turned on;

(VII) Receive start completion signal S7

After the working inverter 3 receives the start signal, it starts to run, and returns to the start completion signal after the start is completed;

(VIII) Send the electronic switch on signal S8

After receiving the start-up completion signal returned by the working inverter 3, send the electronic switch assembly 25 on signal to turn on the electronic switch assembly 25;

(IX) Turn on connection S9

After the electronic switch assembly 25 is turned on, the connection of the entire working trunk line is completed, the connection with the load is turned on, and the power supply is output;

II dynamic switching control program

(X) Initialize S10

start initialization;

(XI) Working inverter status S11

Receive the start completion signal of the working inverter 3;

(XII) Remote control S12

Set the control mode and select remote control;

(XIII) Switch state selection S13

Under the condition of remote control, the state of the transfer switch 23 is detected, if the standby inverter 4 is selected, then step S14 is executed; if the maintenance inverter 5 is selected, step S20 is executed;

(XIV) Working inverter fault judgment S14

According to the fault signal of the working inverter 3, judge whether the working inverter 3 is faulty, if the working inverter 3 is faulty, it will return, if there is no fault, go to the next step;

(XV) Send start signal S15

Send a start signal to the standby frequency converter 4;

(XVI) Send the contactor on signal S16

After sending the starting signal of the standby inverter 4 or the maintenance inverter 5, the No. Ⅱ loop contactor 24 is turned on;

(XVII) Receive start completion signal S17

After the standby inverter 4 or the maintenance inverter 5 receives the start signal, it starts to run, and returns to the start completion signal after the start is completed;

(XVIII) Send the electronic switch on signal S18

After receiving the start-up completion signal of the standby frequency converter 4 or the maintenance frequency converter 5, send the electronic switch assembly 25 on signal to turn on the electronic switch assembly 25;

(XIV) Turn on connection S19

After the electronic switch assembly 25 is turned on, the connection of the entire backup/maintenance trunk line is completed, the connection with the load is turned on, and the power supply is output;

(XX) Working inverter fault judgment S20

According to the fault signal of the working inverter 3, judge whether the working inverter 3 is faulty, if the working inverter 3 is faulty, it will return, if there is no fault, go to the next step;

(XXI) Send start signal S21

Send a start signal to the maintenance inverter 5.

The invention provides a dynamic switching device of a frequency converter with a remote control function based on PLC control, which ensures the continuous operation of the power supply system. It can be applied to motor loads with long-term operation and high continuity of power supply. In the dynamic switching device, the PLC controller can realize the function of remote control and dynamic switching of inverters, which can achieve rapid switching of inverter failures and avoid the possibility of human operation errors. The reliability and safety of the dynamic switching device in the power supply system are effectively improved, and the continuity requirements of long-term power supply can be met.

It should be noted that the embodiments of the present invention and the features of the embodiments may be combined with each other under the condition of no conflict.

In the description of the present invention, it should be understood that the terms "center", "portrait", "horizontal", "top", "bottom", "front", "rear", "left", "right", " The orientation or positional relationship indicated by vertical, horizontal, top, bottom, inner, outer, etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and The description is simplified rather than indicating or implying that the device or element referred to must have a particular orientation, be constructed and operate in a particular orientation, and therefore should not be construed as limiting the invention. In addition, the terms "first", "second", etc. are used for descriptive purposes only, and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. Thus, a feature defined as "first", "second", etc., may expressly or implicitly include one or more of that feature. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

In the description of the present invention, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense, unless otherwise expressly specified and limited, for example, it may be a fixed connection or a detachable connection Connection, or integral connection; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific situations.

The applicant declares that the above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should Changes or substitutions that can be easily conceived within the technical scope all fall within the protection scope and disclosure scope of the present invention.

Claims (8)

1. a kind of dynamic switching device for remote control frequency converter, it is characterized in that: comprise PLC controller (1) and the switching circuit (2) that multiple groups are arranged in parallel; The output terminal of the inverter (3), the standby inverter (4) and the maintenance inverter (5) are connected, and the output terminal is connected to the load (6); The PLC controller (1) includes an input signal module and an output signal module, the input signal module collects required state signals, and the output signal module sends a drive signal; The switching loop (2) is connected to the PLC controller (1); the switching loop (2) includes a working trunk line and a backup/maintenance trunk line that are connected in parallel with each other, The working trunk line comprises an isolation switch (21) and a No. 1 loop contactor (22) connected in series, the upper port of the isolation switch (21) is connected to the output end of the working frequency converter (3), and the lower port is connected to the No. 1 loop contactor (22) catchy; The standby/maintenance trunk line includes a series-connected transfer switch (23) and a No. II loop contactor (24), and the transfer switch (23) has two sets of upper ports, which are respectively connected to the standby frequency converter (4) and the maintenance frequency converter (5) , its lower port is connected to the No. Ⅱ loop contactor (24); The lower ports of the No. I loop contactor (22) and the No. II loop contactor (24) are both connected to the upper port of the electronic switch assembly (25), and the lower port of the electronic switch assembly (25) is connected to the upper port of the shorting contactor (26) Connect with the upper port of the output terminal and the lower port of the short-circuit contactor (26) for short-circuit connection, and the lower port of the output terminal is connected to the load (6). 2 . The dynamic switching device for remote control of frequency converters according to claim 1 , wherein the switching loops ( 2 ) are in three groups. 3 . 3 . The dynamic switching device for remote control of frequency converters according to claim 1 , wherein the input signal module is used to collect external control signals, and the external control signals include panel button signals and frequency converter status signals. 4 . , Loop device status signal, sensor acquisition parameter signal. 4. The dynamic switching device for remote control of a frequency converter according to claim 3, wherein the frequency converter status signal comprises a start-up completion signal, a fault signal, and a power failure signal; the loop device comprises an isolation switch, a contact The sensor includes a voltage sensor and a current sensor. 5. The dynamic switching device for remote control of a frequency converter according to claim 1, wherein the output signal module sends control signals to the working frequency converter (3), the standby frequency converter (4), the maintenance frequency converter (5) and loop devices. 6 . The dynamic switching device for remote control of the frequency converter according to claim 5 , wherein the control signal includes a start signal and a stop signal. 7 . 7 . The dynamic switching device for remote control of a frequency converter according to claim 5 , wherein the loop device comprises a loop contactor and a shorting contactor. 8 . 8 . The dynamic switching device for remote control of a frequency converter according to claim 1 , wherein the output signal module sends the collected parameter data and operation records and fault records to the host computer and the touch screen for display. 9 .

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