Dual-motor variable frequency-to-power frequency circuit

Abstract

The utility model discloses a dual-motor variable frequency-to-power frequency circuit, which comprises a frequency converter, a conversion module, a driving module, a first main motor, a second main motor and a controller, the power supply input end of the frequency converter is connected with a three-phase power supply, and the output end of the frequency converter is connected with the first input end of the conversion module; the second input end of the conversion module is connected with the power input end of the frequency converter, the conversion module is connected with the first main motor, the input end of the driving module is connected with the three-phase power supply, the output end of the driving module is connected with the second main motor, and the output end of the controller is connected with the control end of the frequency converter and the control end of the driving module. The circuit can be applied to a double-motor sand making machine, and a more efficient and more stable crushing process is realized by driving the first main motor and the second main motor of the sand making machine. The first main motor is driven through the frequency converter and the conversion module, conversion between a variable frequency driving mode and a power frequency driving mode can be achieved, and flexible adjustment of the driving mode of the first main motor is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of sand making machine control circuits, in particular to a dual-motor frequency conversion to industrial frequency circuit. Background Art

[0002] Sand making machine, also known as impact crusher, is used to crush and plastically shape raw materials to produce artificial sand that meets the requirements. It can crush various hard materials such as rocks and ores into particles that meet the standards for construction sand. It is the core equipment for producing machine-made sand. The working principle of sand making machine is mainly to crush and plastically shape the raw materials through the combination of high-speed rotating rotor and crushing chamber.

[0003] In order to improve the crushing efficiency and enhance the working stability of the sand making machine, sand making machines equipped with dual motors have appeared on the market. The dual motors independently drive the different motion mechanisms of the sand making machine, making the crushing process more efficient and more stable. However, there are still some problems with the current dual-motor sand making machines. First, the motor speed cannot be adjusted in real time according to the production load, which results in the two motors still running at high power at the same time when the production load is low, causing unnecessary energy waste; it is also impossible to achieve precise control of the motor speed, resulting in difficulty in ensuring the sand making efficiency and sand and gravel quality. Utility Model Content

[0004] The purpose of the utility model is to provide a dual-motor variable frequency to industrial frequency circuit to solve one or more technical problems existing in the above-mentioned background technology.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] A dual-motor variable frequency to industrial frequency circuit comprises a frequency converter, a conversion module, a drive module, a first main motor, a second main motor and a controller, wherein the power input end of the frequency converter is connected to a three-phase power supply, the output end of the frequency converter is connected to a first input end of the conversion module, the second input end of the conversion module is connected to the power input end of the frequency converter, the first output end and the second output end of the conversion module are both connected to the first main motor, the input end of the drive module is connected to the three-phase power supply, the output end of the drive module is connected to the second main motor, and the output end of the controller is connected to a control end of the frequency converter and a control end of the drive module.

[0007] Preferably, the conversion module includes conversion contactors KMa and KMb, the main contacts of the conversion contactor KMa are respectively connected to the output end of the inverter and the first main motor, the main contacts of the conversion contactor KMb are respectively connected to the power input end of the inverter and the first main motor, and the coil end of the conversion contactor KMa is interlocked with the coil end of the conversion contactor KMb.

[0008] Preferably, the normally open contact of the conversion contactor KMb, the normally closed contact of the conversion contactor KMa, and the coil end of the conversion contactor KMb are connected in series with the first phase and the third phase of the three-phase power supply.

[0009] Preferably, the conversion module also includes an intermediate relay KAa, the normally open contact of the intermediate relay KAa, the normally closed contact of the conversion contactor KMb and the coil end of the conversion contactor KMa are connected in series with the first phase and the third phase of the three-phase power supply, and the coil end of the intermediate relay KAa is connected to the status output end of the inverter and the AC power supply.

[0010] Preferably, the drive module includes an AC contactor KM2, main contacts of the AC contactor KM2 are respectively connected to the three-phase power supply and the second main motor, and coil ends of the AC contactor KM2 are respectively connected to the first phase and the third phase of the three-phase power supply.

[0011] Preferably, the conversion module also includes intermediate relays KA1 and KA3, the normally open contact of the intermediate relay KA1 is connected to the digital input end of the frequency converter, and the coil end of the intermediate relay KA1 is connected to the input end of the controller; the coil end of the intermediate relay KA3 is connected to the digital output end of the frequency converter, and the normally open contact of the intermediate relay KA3 is connected to the input end of the controller.

[0012] Preferably, main circuit breakers Q1 and Q2 are also included, the main circuit breaker Q1 is respectively connected to the three-phase power supply and the power input terminal of the inverter, and the main circuit breaker Q2 is respectively connected to the three-phase power supply and the main contacts of the AC contactor KM2.

[0013] The beneficial effects of the utility model are as follows: the circuit of the utility model can be applied to a dual-motor sand making machine, and a more efficient and stable crushing process is achieved by driving the first main motor and the second main motor of the sand making machine. Among them, the first main motor is driven by the frequency converter and the conversion module, and the conversion between the variable frequency drive mode and the industrial frequency drive mode can be realized, and the flexible adjustment of the drive of the first main motor can be realized to meet various production needs; and the second main motor is driven by the drive module to ensure that the sand making machine has basic crushing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The accompanying drawings further illustrate the present invention, but the contents in the accompanying drawings do not constitute any limitation to the present invention.

[0015] Figure 1 It is a circuit diagram of one embodiment of the utility model;

[0016] Figure 2 It is a circuit diagram of the first main motor and the second main motor of one embodiment of the utility model;

[0017] Figure 3 It is a circuit diagram of the conversion contactors KMa and KMb of one embodiment of the utility model;

[0018] Figure 4 It is a circuit diagram of the controller input end of one embodiment of the utility model;

[0019] Figure 5 It is a circuit diagram of the output end of the controller of one embodiment of the present utility model. DETAILED DESCRIPTION

[0020] The technical solution of the utility model is further explained below with reference to the accompanying drawings and through specific implementation methods.

[0021] A dual-motor variable frequency to industrial frequency circuit in this embodiment is shown in FIG. Figure 1 , including a frequency converter, a conversion module, a drive module, a first main motor M1, a second main motor M2 and a controller, the power input end of the frequency converter is connected to the three-phase power supply, the output end of the frequency converter is connected to the first input end of the conversion module, the second input end of the conversion module is connected to the power input end of the frequency converter, the first output end and the second output end of the conversion module are both connected to the first main motor M1, the input end of the drive module is connected to the three-phase power supply, the output end of the drive module is connected to the second main motor, and the output end of the controller is connected to the control end of the frequency converter and the control end of the drive module.

[0022] This embodiment is provided with a first main motor M1 and a second main motor M2 to form a dual-motor sand making machine. Through the simultaneous operation of the dual motors, the crushing process is made more efficient and more stable. By setting a frequency converter and a conversion module to drive the first main motor M1, in the variable frequency mode, the frequency converter is used to adjust the frequency of the first main motor M1, so that the precise control of the main shaft speed of the sand making machine can be achieved. When the processing capacity of the sand making machine increases, the speed of the first main motor M1 can be increased by the frequency converter to improve the crushing efficiency. When low-power operation is required, the speed of the first main motor M1 can be reduced by the frequency converter, which can effectively reduce energy consumption and achieve energy saving effects. Therefore, the variable frequency drive mode can ensure that the first main motor M1 operates at the highest efficiency point, further improving the energy utilization efficiency. When variable frequency regulation is not required, the frequency converter can also be disconnected from the first main motor M1 through the conversion module to achieve power frequency drive. The adjustment method is more flexible and suitable for more production occasions. The use of variable frequency drive can also control the soft start and soft stop of the first main motor M1, reducing the impact on the power grid and mechanical equipment and extending the service life of the equipment. When the sand making machine is started, the motor speed is gradually increased by the frequency converter to avoid mechanical stress caused by sudden start-up, and when it stops, the speed is gradually reduced to reduce the damage to the equipment caused by inertia. In this embodiment, the second main motor M2 is driven by the drive module to ensure basic crushing efficiency. Therefore, under the premise that the second main motor M2 maintains a certain crushing efficiency, the speed of the first main motor M1 is adjusted by the frequency converter, and the adjustment of the crushing efficiency is more convenient, and there is no need to add another frequency converter, saving equipment costs. By connecting the controller to the frequency converter and the drive module, the frequency converter can be adjusted by changing the output of the controller, which makes the operation of the sand making machine more flexible and convenient to meet different production needs.

[0023] Preferably, refer to the attached Figure 2 and 3 The conversion module includes conversion contactors KMa and KMb. The main contacts of the conversion contactor KMa are respectively connected to the output end of the frequency converter and the first main motor M1. The main contacts of the conversion contactor KMb are respectively connected to the power input end of the frequency converter and the first main motor M1. The coil end of the conversion contactor KMa is interlocked with the coil end of the conversion contactor KMb. When the conversion contactor KMa is closed, the motor is driven by the frequency converter to achieve frequency conversion control; when the conversion contactor KMb is closed, the motor is directly driven by the three-phase power supply. Thus, the switching between the variable frequency mode and the industrial frequency mode is controlled by the conversion contactors KMa and KMb, making the switching between the variable frequency and the industrial frequency of the circuit simpler and more direct. The conversion contactor KMa is interlocked with the conversion contactor KMb to reduce the possibility of operating errors and improve the reliability of the system.

[0024] Furthermore, the normally open contact of the conversion contactor KMb, the normally closed contact of the conversion contactor KMa, and the coil end of the conversion contactor KMb are connected in series with the first phase and the third phase of the three-phase power supply. By controlling the normally open auxiliary contact of the conversion contactor KMb to close, the coil end of the conversion contactor KMb can be energized, and then the main coil of the conversion contactor KMb is closed, so that the first main motor M1 is connected to the frequency converter, and the frequency conversion mode is started.

[0025] Furthermore, the conversion module also includes an intermediate relay KAa, the normally open contact of the intermediate relay KAa, the normally closed contact of the conversion contactor KMb, and the coil end of the conversion contactor KMa are connected in series with the first phase and the third phase of the three-phase power supply, and the coil end of the intermediate relay KAa is connected to the state output end of the inverter and the AC power supply. When it is necessary to switch to the industrial frequency power supply to the first main motor M1, the coil end of the conversion contactor KMa can be energized by closing the normally open contact of the intermediate relay KAa, so that the main contact of KMa is closed, and the first main motor M1 is connected to the three-phase power supply through the main contact of the conversion contactor KMa, so as to realize the industrial frequency mode startup.

[0026] Preferably, the drive module includes an AC contactor KM2, the main contacts of the AC contactor KM2 are respectively connected to the three-phase power supply and the second main motor, and the coil ends of the AC contactor KM2 are respectively connected to the first phase and the third phase of the three-phase power supply. Thus, by controlling the opening and closing of the main contacts of the AC contactor KM2, the opening and closing of the second main motor M2 can be controlled.

[0027] Preferably, refer to the attached Figure 4 and 5 The conversion module also includes intermediate relays KA1 and KA3. The normally open contact of the intermediate relay KA1 is connected to the digital input terminal of the frequency converter, and the coil end of the intermediate relay KA1 is connected to the input terminal of the controller; the coil end of the intermediate relay KA3 is connected to the digital output terminal of the frequency converter, and the normally open contact of the intermediate relay KA3 is connected to the input terminal of the controller. The controller controls the start and stop of the frequency converter by setting the intermediate relay KA1. When the frequency converter is started, the controller outputs a signal to turn on and off the coil of the intermediate relay KA1, so that the normally open contact of the intermediate relay KA1 is closed, and the frequency converter is started. By setting the intermediate relay KA3, when the frequency converter fails, its output signal is sent to the intermediate relay KA3, so that the coil end of the intermediate relay KA3 is energized, and the normally open contact of the intermediate relay KA3 is closed, so that the frequency converter fault signal is input into the controller, which is convenient for the operator to obtain the fault condition.

[0028] It also includes main circuit breakers Q1 and Q2. The main circuit breaker Q1 is connected to the three-phase power supply and the power input terminal of the frequency converter, and the main circuit breaker Q2 is connected to the three-phase power supply and the main contact of the AC contactor KM2. By setting the main circuit breakers Q1 and Q2, the first main motor M1 and the second main motor M2 are electrically protected.

[0029] The technical principle of the present invention is described above in combination with specific embodiments. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the protection scope of the present invention in any way. Based on the explanations here, technicians in this field can think of other specific implementation methods of the present invention without creative work, and these methods will fall within the protection scope of the present invention.

Claims

1. A dual-motor variable frequency to industrial frequency circuit, characterized in that: It includes a frequency converter, a conversion module, a drive module, a first main motor, a second main motor and a controller, wherein the power input end of the frequency converter is connected to a three-phase power supply, the output end of the frequency converter is connected to a first input end of the conversion module, the second input end of the conversion module is connected to the power input end of the frequency converter, the first output end and the second output end of the conversion module are both connected to the first main motor, the input end of the drive module is connected to the three-phase power supply, the input end of the drive module is connected to the second main motor, and the output end of the controller is connected to a control end of the frequency converter and a control end of the drive module.

2. A dual-motor variable frequency to industrial frequency circuit according to claim 1, characterized in that: The conversion module includes conversion contactors KMa and KMb, the main contacts of the conversion contactor KMa are respectively connected to the output end of the inverter and the first main motor, the main contacts of the conversion contactor KMb are respectively connected to the power input end of the inverter and the first main motor, and the coil end of the conversion contactor KMa is interlocked with the coil end of the conversion contactor KMb.

3. A dual-motor variable frequency to industrial frequency circuit according to claim 2, characterized in that: The normally open contact of the conversion contactor KMb, the normally closed contact of the conversion contactor KMa and the coil end of the conversion contactor KMb are connected in series with the first phase and the third phase of the three-phase power supply.

4. A dual-motor variable frequency to industrial frequency circuit according to claim 2, characterized in that: The conversion module also includes an intermediate relay KAa, whose normally open contacts, normally closed contacts of the conversion contactor KMb and the coil end of the conversion contactor KMa are connected in series with the first phase and the third phase of the three-phase power supply, and the coil end of the intermediate relay KAa is connected to the state output end of the inverter and the AC power supply.

5. A dual-motor variable frequency to industrial frequency circuit according to claim 1, characterized in that: The driving module includes an AC contactor KM2, the main contacts of the AC contactor KM2 are respectively connected to the three-phase power supply and the second main motor, and the coil ends of the AC contactor KM2 are respectively connected to the first phase and the third phase of the three-phase power supply.

6. A dual-motor variable frequency to industrial frequency circuit according to claim 3, characterized in that: The conversion module also includes intermediate relays KA1 and KA3, the normally open contact of the intermediate relay KA1 is connected to the digital input end of the inverter, and the coil end of the intermediate relay KA1 is connected to the input end of the controller; the coil end of the intermediate relay KA3 is connected to the digital output end of the inverter, and the normally open contact of the intermediate relay KA3 is connected to the input end of the controller.

7. A dual-motor variable frequency to industrial frequency circuit according to claim 5, characterized in that: It also includes main circuit breakers Q1 and Q2. The main circuit breaker Q1 is connected to the three-phase power supply and the power input terminal of the inverter respectively, and the main circuit breaker Q2 is connected to the three-phase power supply and the main contact of the AC contactor KM2 respectively.

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