Motor frequency conversion control circuit of elevator bucket type mixing plant

Abstract

The utility model relates to the technical field of mixing station motor electrical control, and particularly discloses an elevator bucket type mixing station motor frequency conversion control circuit which comprises a frequency converter and an elevator bucket motor, the output end of the frequency converter is connected with the elevator bucket motor through a cable, and the signal input end of the frequency converter is connected with the signal output end of a controller through a communication cable. The controller sends an instruction to the frequency converter to control the work of the elevator bucket motor, the frequency converter and the controller are both installed in an electric control cabinet on the elevator bucket motor site, and the frequency converter is further provided with a power interface circuit and a switch control circuit; the control mode of the elevator bucket motor is changed from power frequency direct starting to frequency conversion control of the frequency converter, and the frequency of the frequency converter is adjusted to 60HZ when the elevator bucket descends, so that the descending speed of the elevator bucket is increased, the descending time is effectively shortened, the energy consumption of a mixing plant is reduced, the production efficiency can be effectively improved during continuous production, and the position of the elevator bucket can be determined; and the frequency conversion node is determined, and control over the elevator bucket motor is more accurate.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of motor electrical control of mixing station, specifically relates to a kind of lifting bucket type mixing station motor frequency conversion control circuit. BACKGROUND

[0002] The lifting bucket motor of mixing station is the key link to ensure the production efficiency and quality of concrete.The function of lifting bucket is to lift raw materials (such as sand, stone, cement, etc.) from the ground to the mixer or storage bin, and the lifting bucket motor is the power source to drive the operation of lifting bucket.The following are some key technical points about the control of mixing station lifting bucket motor:

[0003] 1.Safety protection mechanism: the lifting bucket motor control system is provided with overload protection, underspeed protection, chain breakage protection and other safety mechanisms.Once abnormal conditions are detected, such as motor overload, lifting speed lower than the set value or chain breakage, the system will immediately shut down and alarm to prevent safety accidents.

[0004] 2.Emergency stop function: an emergency stop button is provided on the control panel, and the operator can immediately press this button to cut off the power supply of the motor in case of emergency to ensure the safety of personnel and equipment.

[0005] 3.Remote monitoring and fault diagnosis: through the integrated monitoring system, the operator can remotely monitor the running state of the lifting bucket motor and perform fault warning and diagnosis to improve maintenance efficiency.

[0006] 4.Communication interface: the lifting bucket motor control system usually has the ability to communicate with the host computer, and through Ethernet, RS485 and other interfaces, the running data is uploaded to the host computer system to realize real-time monitoring and analysis of production data.

[0007] 5.Energy-saving optimization: under the premise of meeting production requirements, the motor control system will adopt energy-saving mode, such as reducing motor speed or turning off motor in standby state to reduce energy consumption.In summary, the control of mixing station lifting bucket motor integrates advanced automation technology and safety protection measures to ensure efficient, safe and energy-saving concrete production process.

[0008] The existing lifting bucket motor directly uses a PLC (programmable logic) controller for control when electrically controlling, and is uploaded to a DCS system in an electric monitoring room. The existing direct control mode generally uses power frequency for control, has speed control of the lifting bucket motor, but the control precision is not high. The lifting bucket uses power frequency in a normal working state when ascending, but if power frequency is also used when the lifting bucket descends in an empty state, energy will be wasted and the descending speed will be slow, which affects production efficiency. Meanwhile, the lifting bucket is in a uniform speed running state, and there is no direct monitoring device for the motor in the system, so the position of the lifting bucket cannot be quickly identified. Therefore, it is urgent to design a lifting bucket type mixing station motor frequency conversion control circuit to solve the problems of low production efficiency caused by low control precision of the existing mixing station lifting bucket motor and inability to determine the position of the lifting bucket. Practical new type content

[0009] In view of the problems in the prior art, the purpose of the present application is to provide a lifting bucket type mixing station motor frequency conversion control circuit.

[0010] The technical scheme adopted by the present application to solve the technical problems is: a lifting bucket type mixing station motor frequency conversion control circuit, comprising a frequency converter and a lifting bucket motor, the output end of the frequency converter is connected to the lifting bucket motor through a cable, the signal input end of the frequency converter is connected to the signal output end of a controller through a communication cable, the controller controls the work of the lifting bucket motor by issuing instructions to the frequency converter, the frequency converter and the controller are both installed in an electric control cabinet on site of the lifting bucket motor, and the frequency converter is further provided with a power interface circuit and a switch control circuit.

[0011] Specifically, an angle encoder is installed on the motor shaft of the lifting bucket motor, the angle encoder is connected to the controller through a communication cable, and the controller identifies the working state of the lifting bucket motor to determine the position of the lifting bucket.

[0012] Specifically, six switch output ports of the controller are connected to six signal input ends of the frequency converter through 4-20mA communication cables, and the controller issues six instructions including a fault reset instruction, an ascending instruction, a stopping instruction, a descending instruction, a forward rotation instruction and a reverse rotation instruction to the frequency converter.

[0013] Specifically, the power interface circuit of the frequency converter uses R input terminals, S input terminals and T input terminals of the frequency converter, the R input terminals, the S input terminals and the T input terminals are three-phase alternating current power input terminals, and the R input terminals, the S input terminals and the T input terminals correspond to R phase, S phase and T phase of the three-phase alternating current power respectively.

[0014] Specifically, the switch control circuit of the inverter uses the A, B, and C relay control terminals of the inverter. The C relay control terminal is connected to the live wire of the power supply, and the A relay control terminal is connected to the switch SB1, switch SB2, contactor KM and the neutral wire of the power supply. The switch SB1 controls the inverter switch.

[0015] Specifically, the three-phase output terminals of the inverter include a U output terminal, a V output terminal and a W output terminal, and the U output terminal, the V output terminal and the W output terminal correspond to the U phase, the V phase and the W phase of the bucket motor respectively.

[0016] The utility model has the following beneficial effects:

[0017] The utility model designs a lifting bucket type mixing station motor frequency conversion control circuit with an additional frequency converter, which changes the control mode of the lifting bucket motor from industrial frequency direct start to frequency conversion control of the frequency converter. When the lifting bucket descends, the frequency converter frequency is adjusted to 60HZ, which increases the lowering speed of the lifting bucket. The lowering time can be increased by 6S compared with the industrial frequency direct start control. The production of each batch of concrete can save 6S time, effectively shortening the descending time, reducing the energy consumption of the mixing station, and effectively improving production efficiency during continuous production.

[0018] The motor frequency conversion control circuit of the bucket mixer station designed by the utility model adopts the angle encoder of the motor to identify the rotation angle of the bucket motor, thereby determining the position of the bucket and the frequency conversion node, and controlling the bucket motor more accurately. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Fig. 1 It is the system framework diagram of the motor frequency conversion control circuit of the bucket mixer station.

[0020] Fig. 2 This is a circuit connection structure diagram of the motor frequency conversion control circuit of the bucket mixer station.

[0021] In the figure: 1-controller; 2-inverter; 3-hoisting bucket motor. DETAILED DESCRIPTION

[0022] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely further describe the technical solutions in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0023] Example 1:

[0024] like Figs. 1-2The figure shows a motor frequency conversion control circuit for a bucket-type mixing station, comprising a controller 1, a frequency converter 2, and a bucket motor 3. The output of frequency converter 2 is connected to the bucket motor 3 via a cable, and the signal input of frequency converter 2 is connected to the signal output of controller 1 via a communication cable. Controller 1 controls the operation of bucket motor 3 by issuing commands to frequency converter 2. Both frequency converter 2 and controller 1 are installed in an on-site electrical control cabinet near bucket motor 3. Controller 1 primarily controls the operating status of frequency converter 2; frequency converter 2, installed in the on-site electrical control cabinet, controls bucket motor 3.

[0025] An angle encoder is installed on the motor shaft of the bucket motor 3, and the angle encoder is connected to the controller 1 through a communication cable. The controller 1 identifies the working status of the bucket motor 3, determines the position of the bucket, and determines the frequency conversion node, so as to control the bucket motor 3 more accurately.

[0026] The six switch output ports of controller 1 are connected to the six signal input ports of inverter 2 through 4-20mA communication cables. Controller 1 sends six instructions to inverter 2, including fault reset instruction, rise instruction, stop instruction, fall instruction, forward instruction and reverse instruction.

[0027] Inverter 2 also has a power interface circuit and a switch control circuit. The power interface circuit of inverter 2 uses the R, S, and T input terminals of inverter 2. The R, S, and T input terminals are three-phase AC power input terminals and correspond to the R, S, and T phases of the three-phase AC power supply, respectively.

[0028] Inverter 2's on / off control circuit uses its A, B, and C relay control terminals. Relay C is connected to the live power line, while relay A is connected to switches SB1, SB2, contactor KM, and the neutral power line. Switch SB1 controls the on / off switching of Inverter 2. To disconnect the main power supply to Inverter 2, press switch SB1. This de-energizes the coil of contactor KM, opens the main contacts of contactor KM, and disconnects the power supply to Inverter 2. Pressing switch SB2 energizes the coil of contactor KM, closing both the normally open auxiliary contacts and the main contacts of contactor KM. The closure of the normally open auxiliary contacts locks the coil of contactor KM, energizing it to self-lock, and closing the main contacts of contactor KM, connecting the main power supply to Inverter 2.

[0029] The three-phase output terminals of the inverter 2 include a U output terminal, a V output terminal, and a W output terminal, which correspond to the U phase, V phase, and W phase of the bucket motor 3 respectively.

[0030] The controller 1 controls to send the ascending, descending and stopping instructions to the frequency converter 2, the frequency converter 2 receives the descending instruction sent by the controller 1, and then the frequency converter 2 outputs the 60HZ frequency control to make the lifting bucket motor 3 quickly descend; the angle encoder identifies that the lifting bucket has descended to the specified position, and then feeds back the position signal to the controller 1; the controller 1 sends the stopping instruction to the frequency converter 2; the frequency converter 2 stops outputting, and the lifting bucket motor 3 is braked to stop.

[0031] The utility model discloses the control mode of lifting bucket motor 3 is changed from power frequency direct starting to frequency converter frequency control, and the frequency converter 1 frequency is adjusted to 60HZ when the lifting bucket descends, so that the descending speed of the lifting bucket is increased, and the descending time can be increased by 6S than the power frequency direct starting control, 6S time can be saved for producing each tray of concrete, and the production efficiency can be effectively improved when continuously producing.

[0032] The utility model is not limited to the above-mentioned embodiment, any person should know the structural change made under the inspiration of the utility model, and any technical scheme with the same or similar utility model falls into the protection scope of the utility model.

[0033] The utility model discloses the technical, shape, configuration part not described in detail are public known technology.

[0034] It should be noted that, in this paper, such as the first and second relationship terms are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations. Moreover, the term "includes", "contains" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or equipment.

[0035] Although the embodiments of the utility model have been shown and described, it can be understood by those skilled in the art that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirits of the utility model, and the scope of the utility model is defined by the appended claims and their equivalents.

Claims

1. A motor frequency conversion control circuit for a lifting bucket mixing station, characterized in that: It includes a frequency converter and a bucket motor. The output end of the frequency converter is connected to the bucket motor via a cable. The signal input end of the frequency converter is connected to the signal output end of the controller via a communication cable. The controller controls the operation of the bucket motor by sending instructions to the frequency converter. The frequency converter and the controller are both installed in an electric control cabinet at the bucket motor site. The frequency converter is also provided with a power interface circuit and a switch control circuit. An angle encoder is installed on the motor shaft of the bucket elevator motor. The angle encoder is connected to the controller via a communication cable. The controller identifies the working status of the bucket elevator motor and determines the position of the bucket elevator. The six switching output ports of the controller are connected to the six signal input ports of the inverter through 4-20mA communication cables. The controller sends six commands to the inverter, including fault reset command, rise command, stop command, fall command, forward command and reverse command. The inverter's switch control circuit uses the inverter's A, B, and C relay control terminals. The C relay control terminal is connected to the power live wire, and the A relay control terminal is connected to switch SB1, switch SB2, contactor KM, and the power neutral wire. Switch SB1 controls the inverter switch.

2. The motor frequency conversion control circuit of the lifting bucket mixing station according to claim 1 is characterized in that: The power interface circuit of the inverter uses the R input terminal, S input terminal, and T input terminal of the inverter. The R input terminal, S input terminal, and T input terminal are three-phase AC power input terminals, and the R input terminal, S input terminal, and T input terminal correspond to the R phase, S phase, and T phase of the three-phase AC power supply respectively.

3. The motor frequency conversion control circuit of the lifting bucket mixing station according to claim 1 is characterized in that: The three-phase output terminals of the frequency converter include a U output terminal, a V output terminal and a W output terminal, which correspond to the U phase, V phase and W phase of the bucket motor respectively.

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