Multi-water pump motor control system based on frequency converter

Abstract

The embodiment of the utility model relates to a multi-water pump motor control system based on a frequency converter, which controls corresponding water pump motors through one frequency converter and a plurality of contactors, has higher adjustability, and can more flexibly control the flow speed and pressure of the water pump motors and control the sequential operation of the water pump motors. Another advantage of the scheme provided by the utility model is that the current controlled water pump motor does not influence other water pump motors and does not influence power consumption equipment except the water pump, so that one frequency converter capable of communicating can control a plurality of water pumps, due to the fact that the size of the frequency converter is large, space can be effectively saved by only using one frequency converter, and the cost is reduced. And the device is suitable for controlling equipment with small space.

Description

Technical Field

[0001] This application relates to the field of electronic control technology, and in particular to a control system for multiple water pump motors based on a frequency converter. Background Technology

[0002] A water pump motor is a power device that converts electrical energy into mechanical energy to drive a water pump, enabling water to be transported, circulated, and pressurized in a pipeline system. Because water pump motors lack frequency regulation, the starting current can impact the control circuit during startup and may also cause the circuit breaker to trip.

[0003] Currently, water pump motors are directly started using air switches and contactors, which has a certain impact on the power supply equipment. Selecting a D-type tripping air switch can prevent tripping. However, if multiple water pump motors in the overall system start alternately or simultaneously, it will seriously interfere with the air switch and other equipment, and in severe cases, it may lead to phase loss. Utility Model Content

[0004] The purpose of this application is to provide a control system for multiple water pump motors based on a frequency converter, which solves the problem in the prior art that when multiple water pump motors in the overall system start alternately or simultaneously, it will cause serious interference to air switches and other equipment.

[0005] To achieve the above objectives, this application provides a multi-pump motor control system based on a frequency converter. The multi-pump motor control system comprises an inverter, an air switch, a PLC controller, a frequency converter, multiple contactors, and a number of pump motors equal to the number of contactors. Specifically, it includes:

[0006] The power supply is connected to the inverter, the inverter is connected to the main power circuit breaker, the other end of the main power circuit breaker is connected to the PLC control cabinet, and the other end of the PLC control cabinet is connected to the frequency converter, the switching power supply, and the socket.

[0007] An air switch is also connected between the frequency converter and the PLC control cabinet. The other end of the frequency converter is connected to each contactor, and each contactor is connected to the corresponding water pump motor. The frequency converter controls the corresponding water pump motor by communicating with the corresponding contactor.

[0008] Furthermore, the inverter outputs three-phase power to the main power circuit breaker, where it is shunted at the lower port of the main power circuit breaker.

[0009] Furthermore, the switching power supply is used to provide low-voltage DC power to the control system of multiple water pump motors.

[0010] Furthermore, the socket is used to reserve a power supply port for subsequent debugging equipment.

[0011] Furthermore, the communication protocol of the frequency converter is the MODBUS RTU protocol.

[0012] Furthermore, the PLC control cabinet is connected to input signals, output signals, analog input signals, and 485 signals;

[0013] The input signals include the start feedback signals of each water pump motor and the frequency converter fault signal. The output signals include the start signals of each water pump motor. The analog input signal is used to read the frequency of the frequency converter.

[0014] Furthermore, the 485 signal includes parameters for setting the rated power, rated current, rated voltage, rated speed, start, stop, and frequency of the controlled equipment of the frequency converter.

[0015] Furthermore, the frequency converter is used to change the rated power, rated current, rated voltage, and rated speed parameters of the frequency converter via communication.

[0016] As can be seen from the above, the technical solution provided by this application has higher adjustability, and can more flexibly control the flow rate and pressure of the water pump motor as well as the sequential operation of the water pump motor. Another advantage of the solution proposed in this application is that the currently controlled water pump motor will not affect other water pump motors, nor will it affect power-consuming equipment other than the water pump. Therefore, one frequency converter that can communicate can control multiple water pumps. Since the frequency converter is relatively large, using only one frequency converter can effectively save space and is suitable for controlling equipment with small space. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the architecture of a multi-pump motor control system based on a frequency converter, as described in an embodiment of this application.

[0018] Figure 2 This is a schematic diagram of a system control system for multiple water pump motors based on a frequency converter, as described in an embodiment of this application. Detailed Implementation

[0019] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this application.

[0020] To address the problem mentioned above where multiple water pump motors within the overall system start alternately or simultaneously, causing severe interference to air switches and other equipment.

[0021] This utility model provides a control system for multiple water pump motors based on a frequency converter. Please refer to [link / reference]. Figure 1 and Figure 2 The multi-pump motor control system consists of an inverter, an air switch, a PLC controller, a frequency converter, multiple contactors, and a number of pump motors equal to the number of contactors, specifically including:

[0022] The power supply is connected to the inverter, the inverter is connected to the main power circuit breaker, the other end of the main power circuit breaker is connected to the PLC control cabinet, and the other end of the PLC control cabinet is connected to the frequency converter, the switching power supply, and the socket.

[0023] An air switch is also connected between the frequency converter and the PLC control cabinet. The other end of the frequency converter is connected to each contactor, and each contactor is connected to the corresponding water pump motor. The frequency converter controls the corresponding water pump motor by communicating with the corresponding contactor.

[0024] Due to the stability of the frequency converter's control over the water pump motor frequency, the entire system consists of an air switch, a frequency converter, and multiple contactors. First, the frequency converter must be selected so that its rated power, rated current, rated voltage, rated speed, and other parameters can be changed via communication. The power supply of the frequency converter is connected to multiple contactors, and each contactor is connected to a water pump motor. The communication protocol with the frequency converter is the MODBUS RTU protocol.

[0025] Furthermore, the inverter outputs three-phase power to the main power circuit breaker, where it is shunted at the lower port of the main power circuit breaker.

[0026] One circuit breaker is dedicated to the frequency converter, and its size is selected according to the rated current of the frequency converter. The frequency converter is selected based on the power of the water pump motor that is turned on simultaneously from the lower end. Another circuit is dedicated to the switching power supply to provide low-voltage DC power to the control system. A third circuit is dedicated to the socket to reserve power supply ports for the equipment debugging equipment.

[0027] Furthermore, the switching power supply is used to provide low-voltage DC power to the control system of multiple water pump motors.

[0028] Furthermore, the socket is used to reserve a power supply port for subsequent debugging equipment.

[0029] Furthermore, the communication protocol of the frequency converter is the MODBUS RTU protocol.

[0030] This utility model embodiment consists of a hardware air switch, a frequency converter, multiple contactors, multiple water pump motors, a switching power supply, a PLC, a 485 module, a battery power supply, and an inverter. First, a DC 330V power supply with a discharge time of 3 hours is selected. The inverter uses three-phase power output with a neutral wire because the control system used with the frequency converter requires AC 220V voltage. The power output from the inverter first goes to the main power air switch in the control cabinet, and then is shunt from the lower end of the power air switch.

[0031] Due to safety considerations and the heat generated during battery use, discharging is prohibited while the battery pack is charging. In actual use, standby time and charging time arrangements need to be considered.

[0032] Furthermore, the PLC control cabinet is connected to input signals, output signals, analog input signals, and 485 signals; the input signals include start feedback signals for each water pump motor and inverter fault signals, the output signals include start signals for each water pump motor, and the analog input signals are used to read the frequency of the inverter.

[0033] Furthermore, the 485 signal includes parameters for setting the rated power, rated current, rated voltage, rated speed, start, stop, and frequency of the controlled equipment of the frequency converter.

[0034] Furthermore, the frequency converter is used to change the rated power, rated current, rated voltage, and rated speed parameters of the frequency converter via communication.

[0035] When there are 6 water pumps, the input signals include: water pump 1 start feedback signal, water pump 2 start feedback signal, water pump 3 start feedback signal, water pump 4 start feedback signal, water pump 5 start feedback signal, water pump 6 start feedback signal, and frequency converter fault signal.

[0036] The output signals include: pump 1 start signal, pump 2 start signal, pump 3 start signal, pump 4 start signal, pump 5 start signal, and pump 6 start signal.

[0037] After the hardware connection is completed, wire the terminal water pump motors in an orderly manner according to the contactor current. Write the manual program for the PLC, confirm that there is no problem with the communication between the frequency converter and the PLC, ensure that the parameters can be adjusted through the MODBUS RTU protocol, and ensure that the communication frequency of the frequency converter is not a problem before starting the water pump motor.

[0038] Since idling can cause irreversible damage to the motor, the water pump motor must meet certain environmental requirements before being powered on, including a sufficient water supply. If the water pump wiring points are not properly insulated from the power connection points, pay attention to the motor's rotation direction upon first power-on. If it rotates in the opposite direction, swap any two of the three power wires (U, V, W) in their positions.

[0039] After the PLC completes the manual program and starts the water pump motors individually, it can write an automatic program according to specific needs. Water pumps 1-6 can be started sequentially, alternately, or several can be started simultaneously to meet the project requirements.

[0040] The foregoing description of various embodiments of this application is provided to those skilled in the art for illustrative purposes. It is not intended to be exhaustive or to limit the invention to a single disclosed embodiment. As mentioned above, various alternatives and variations of this application will be apparent to those skilled in the art to which the foregoing pertains. Therefore, while some alternative embodiments have been specifically discussed, other embodiments will be obvious or readily apparent to those skilled in the art. This application is intended to include all alternatives, modifications, and variations of the invention already discussed herein, as well as other embodiments falling within the spirit and scope of the foregoing application.

Claims

1. A control system for multiple water pump motors based on a frequency converter, characterized in that, The multi-pump motor control system consists of an inverter, an air switch, a PLC controller, a frequency converter, multiple contactors, and a number of pump motors equal to the number of contactors, specifically including: The power supply is connected to the inverter, the inverter is connected to the main power circuit breaker, the other end of the main power circuit breaker is connected to the PLC control cabinet, and the other end of the PLC control cabinet is connected to the frequency converter, the switching power supply, and the socket. An air switch is also connected between the frequency converter and the PLC control cabinet. The other end of the frequency converter is connected to each contactor, and each contactor is connected to the corresponding water pump motor. The frequency converter controls the corresponding water pump motor by communicating with the corresponding contactor.

2. The control system for multiple water pump motors according to claim 1, characterized in that, The inverter outputs three-phase power to the main power circuit breaker, where it is shunt at the lower port of the main power circuit breaker.

3. The control system for multiple water pump motors according to claim 1, characterized in that, The switching power supply is used to provide low-voltage DC power to the control system of multiple water pump motors.

4. The control system for multiple water pump motors according to claim 1, characterized in that, The socket is used to reserve a power supply port for subsequent debugging equipment.

5. The control system for multiple water pump motors according to claim 1, characterized in that, The communication protocol of the frequency converter is the MODBUS RTU protocol.

6. The control system for multiple water pump motors according to claim 1, characterized in that, The PLC control cabinet is connected to input signals, output signals, analog input signals, and 485 signals. The input signals include the start feedback signals of each water pump motor and the frequency converter fault signal. The output signals include the start signals of each water pump motor. The analog input signal is used to read the frequency of the frequency converter.

7. The control system for multiple water pump motors according to claim 6, characterized in that, The 485 signal includes parameters for setting the rated power, rated current, rated voltage, rated speed, start, stop, and frequency of the controlled equipment of the frequency converter.

8. The control system for multiple water pump motors according to claim 1, characterized in that, The frequency converter is used to change its rated power, rated current, rated voltage, and rated speed parameters via communication.

Images