Energy-saving water slime pump control circuit

Abstract

The utility model discloses an energy-saving control circuit for a water slime pump. The energy-saving control circuit comprises a control loop and a main loop, the main loop comprises a frequency converter F, one end of the frequency converter F is connected with a power supply through a normally open contact of a circuit breaker QF, the other end of the frequency converter F is connected with a first motor M1, a coil of a current relay KI is connected between the normally open contact of the circuit breaker QF and a phase C of the power supply, and a normally open contact of an intermediate relay KA is connected between an FWD contact and a COM contact of the frequency converter F. A second motor M2 is connected between the frequency converter F and the normally open contact of the circuit breaker QF through the normally open contact of the contactor KM; the control loop comprises a first branch, a second branch and a third branch.

Description

Technical Field

[0001] This utility model relates to the field of circuit technology, specifically to an energy-saving water-coal slurry pump control circuit. Background Technology

[0002] In the actual production of many coal mining enterprises in my country, the frequent start-up and shutdown of coal slurry pumps and load changes result in a high frequency of use of frequency converter F. Over time, this can easily cause wear and tear and failure of the circuit board of frequency converter F, affecting the normal operation of the equipment. At the same time, when the load of the coal slurry pump is stable, the frequency converter F continues to be used in full-pressure operation mode, which also reduces the service life of frequency converter F, increases maintenance costs, and often results in a waste of frequency converter F resources. Utility Model Content

[0003] The purpose of this invention is to provide an energy-saving control circuit for a coal slurry pump.

[0004] This utility model is implemented by the following technical solution: an energy-saving water-coal slurry pump control circuit, which includes a control circuit and a main circuit;

[0005] The main circuit includes a frequency converter F. One end of the frequency converter F is connected to the power supply through the normally open contact of the circuit breaker QF. The other end of the frequency converter F is connected to the first motor M1. The coil of the current relay KI is connected between the normally open contact of the circuit breaker QF and the C phase of the power supply. The normally open contact of the intermediate relay KA is connected between the FWD contact and the COM contact of the frequency converter F. The normally open contact of the frequency converter F and the normally open contact of the circuit breaker QF is connected to the normally open contact of the contactor KM. The other end of the thermal relay FR is connected to the second motor M2.

[0006] The control loop includes a first branch, a second branch, and a third branch;

[0007] The first branch includes a normally open contact of a circuit breaker QF, a normally closed contact of a contactor KM, a normally open contact of a current relay KI, and a coil of a first time relay KT1, which are connected in series. The normally open contact of the current relay KI and the coil of the first time relay KT1 are connected in parallel with a time-delayed disconnect contact of the first time relay KT1 and a coil of the intermediate relay KA.

[0008] The second branch is connected in parallel between the normally closed contact of the contactor KM, the normally open contact of the current relay KI, and the coil of the first time relay KT1 in the first branch.

[0009] The second branch includes the normally closed contact of the intermediate relay KA, the delayed closing contact of the first time relay KT1, the normally closed contact of the second time relay KT2, the coil of the contactor, and the normally closed contact of the thermal relay FR, which are connected in series. The delayed closing contact of the first time relay KT1 is connected in parallel with the normally open contact of the contactor KM.

[0010] The second branch is connected in parallel with the third branch, which includes the normally closed contact of the current relay KI and the coil of the second time relay KT2, which are connected in series.

[0011] The advantages of this utility model are: through the cooperation of the control circuit and the main circuit, the dynamic adjustment of the motor operation of the coal slurry pump is realized. When the current reaches the set value for a long time, the switching between frequency conversion operation and power frequency operation can be realized automatically. When the current is lower than the set value, the frequency conversion operation is immediately realized. Therefore, the control circuit is more flexible, minimizing the usage time of the frequency converter F and reducing its operation and maintenance costs.

[0012] It can switch to the full-pressure operation mode of the conventional circuit in a timely manner according to the actual load conditions, saving energy and reducing operating costs. When the load of the coal slurry pump is stable, the full-pressure operation mode of the coal slurry pump can meet the normal operation requirements of production.

[0013] For coal slurry pumps that frequently start and stop, a frequency converter F is used during the startup phase. Once normal operation is achieved, the system is immediately switched to the conventional circuit. This minimizes the usage time of the frequency converter F and reduces its operation and maintenance costs. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the control circuit of the present invention;

[0016] Figure 2 This is a schematic diagram of the main circuit of the utility model;

[0017] In the diagram: control circuit 1, main circuit 2, frequency converter F, circuit breaker QF, power supply, first motor M1, intermediate relay KA, contactor KM, second motor M2, first branch 11, second branch 12, third branch 13, current relay KI, first time relay KT1, second time relay KT2, thermal relay FR. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0019] like Figure 1-2 As shown, the energy-saving water-coal slurry pump control circuit includes a control circuit 1 and a main circuit 2.

[0020] The main circuit includes a frequency converter F. One end of the frequency converter F is connected to the power supply through the normally open contact of the circuit breaker QF. The other end of the frequency converter F is connected to the first motor M1. The coil of the current relay KI is connected between the normally open contact of the circuit breaker QF and the C phase of the power supply. The normally open contact of the intermediate relay KA is connected between the FWD contact and the COM contact of the frequency converter F. The normally open contact of the frequency converter F and the normally open contact of the circuit breaker QF is connected to the normally open contact of the contactor KM. The other end of the thermal relay FR is connected to the second motor M2.

[0021] The control loop 1 includes a first branch 11, a second branch 12, and a third branch 13;

[0022] The first branch 11 includes a normally open contact of a circuit breaker QF, a normally closed contact of a contactor KM, a normally open contact of a current relay KI, and a coil of a first time relay KT1, which are connected in series. The normally open contact of the current relay KI and the coil of the first time relay KT1 are connected in parallel with a time-delayed disconnect contact of the first time relay KT1 and a coil of an intermediate relay KA.

[0023] The second branch 12 is connected in parallel between the normally closed contact of the contactor KM, the normally open contact of the current relay KI, and the coil of the first time relay KT1 in the first branch 11.

[0024] The second branch 12 includes the normally closed contact of the intermediate relay KA, the delayed closing contact of the first time relay KT1, the normally closed contact of the second time relay KT2, the coil of the contactor, and the normally closed contact of the thermal relay FR, which are connected in series. The delayed closing contact of the first time relay KT1 is connected in parallel with the normally open contact of the contactor KM.

[0025] The second branch 12 is connected in parallel with the third branch 13, which includes the normally closed contact of the current relay KI and the coil of the second time relay KT2, which are connected in series.

[0026] The specific operation process of this embodiment is as follows:

[0027] When the circuit breaker QF is closed, the coil of the intermediate relay KA is energized, the normally open contact of the intermediate relay KA on the inverter F in the main circuit 2 closes, the inverter F starts running, and the motor M1 starts working.

[0028] The current in the main circuit 2 is not yet sufficient to reach the operating current set by the current relay KI. The coil of the second time relay KT2 in the third branch 13 is energized, and the normally closed contact of the second time relay KT2 in the second branch 12 is open. At this time, the coil of the contactor KM is disconnected, and the normally open contact of the contactor KM in the main circuit 2 is in the open state, so that the motor M2 is not energized.

[0029] In the main circuit 2, when the current relay KI reaches the set value, the coil of the current relay KI is energized, and the normally closed contact of the current relay KI in the third branch 13 is opened. At this time, the coil of the second time relay KT2 is de-energized.

[0030] In the first branch 11, the normally open contact of the current relay KI closes, the coil of the first time relay KT1 is energized, and the first time relay KT1 starts timing. After the set time is reached, the delay disconnect contact of the first time relay KT1 opens, and the coil of the intermediate relay KA is disconnected.

[0031] At the same time, the delayed closing contact of the first time relay KT1 in the second branch 12 closes, the coil of contactor KM is energized and self-locked, and motor M2 starts to run;

[0032] In the first branch 11, the normally closed contact of contactor KM opens, the coil of intermediate relay KA is de-energized, and motor M1 stops running;

[0033] When the current is less than the set value, the coil of the current relay KI is de-energized, the normally closed contact of the current relay KI in the third branch 13 is closed, the coil of the second time relay KT2 is energized, the normally closed contact of the second time relay KT2 in the second branch 12 disconnects the coil circuit of the contactor KM, and the motor M2 stops running.

[0034] In the first branch 11, the normally closed contact of contactor KM is closed, the coil of intermediate relay KA is energized, the frequency converter F starts running again, and motor M1 starts working.

[0035] Repeat the above steps;

[0036] By coordinating control circuit 1 and main circuit 2, dynamic adjustment of motor operation is achieved. When the current reaches the set value for an extended period, the system can automatically switch between variable frequency and mains frequency operation. When the current falls below the set value, the system immediately switches to variable frequency operation, offering greater flexibility and minimizing the usage time of the frequency converter F, thus reducing its operation and maintenance costs. The system can also switch to the full-voltage operation mode of the conventional circuit as needed based on the actual load conditions, saving energy and reducing operating costs. When the coal slurry pump load is stable, the full-voltage operation mode can meet the normal operation requirements of production. For coal slurry pumps that frequently start and stop, the frequency converter F is used during the startup phase, and once normal operation is achieved, the system immediately switches to the conventional circuit, minimizing the usage time of the frequency converter F and reducing its operation and maintenance costs.

[0037] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An energy-saving water-coal slurry pump control circuit, characterized in that, It includes a control circuit and a main circuit; The main circuit includes a frequency converter F. One end of the frequency converter F is connected to the power supply through the normally open contact of the circuit breaker QF. The other end of the frequency converter F is connected to the first motor M1. The coil of the current relay KI is connected between the normally open contact of the circuit breaker QF and the C phase of the power supply. The normally open contact of the intermediate relay KA is connected between the FWD contact and the COM contact of the frequency converter F. The normally open contact of the frequency converter F and the normally open contact of the circuit breaker QF is connected to the normally open contact of the contactor KM. The other end of the thermal relay FR is connected to the second motor M2. The control loop includes a first branch, a second branch, and a third branch; The first branch includes a normally open contact of a circuit breaker QF, a normally closed contact of a contactor KM, a normally open contact of a current relay KI, and a coil of a first time relay KT1, which are connected in series. The normally open contact of the current relay KI and the coil of the first time relay KT1 are connected in parallel with a time-delayed disconnect contact of the first time relay KT1 and a coil of the intermediate relay KA. The second branch is connected in parallel between the normally closed contact of the contactor KM, the normally open contact of the current relay KI, and the coil of the first time relay KT1 in the first branch. The second branch includes the normally closed contact of the intermediate relay KA, the delayed closing contact of the first time relay KT1, the normally closed contact of the second time relay KT2, the coil of the contactor, and the normally closed contact of the thermal relay FR, which are connected in series. The delayed closing contact of the first time relay KT1 is connected in parallel with the normally open contact of the contactor KM. The second branch is connected in parallel with the third branch, which includes the normally closed contact of the current relay KI and the coil of the second time relay KT2, which are connected in series.

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