Double-starting drying roller
By adopting a dual-start method in the drying drum, combining direct start and frequency conversion start, and using the combination of relay and frequency converter, the grid impact and start failure caused by the single starting method of the traditional drying drum is solved, and a more stable Motor operation and grid safety.
Patent Information
- Application Number
- CN202420225793.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-30
- Publication Date
- 2024-12-13
- Estimated Expiration
- 2034-01-30
AI Technical Summary
The drying drum starts with traditional asphalt mixture mixing equipment, and the power grid impact is large and unfavorable to the drum when it is started. When the star triangle starts, it is easy to fail in the case of material.
A double-start drying drum is designed, using two methods: direct start and frequency conversion start. Through the combination of multiple relays and frequency converters, the starting method is selected according to actual conditions, reducing the starting impulse and avoiding start failure.
It effectively reduces the starting momentum, avoids the start-up failure, ensures the stable operation of the motor and the safety of the power grid, and is suitable for different working conditions.
Smart Images
Figure CN222165502U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a double-start drying drum. Background Art
[0002] The traditional drying drum of asphalt mixing equipment has a single starting method, either direct starting or star-delta starting, but both methods have defects: direct starting will have a large instantaneous starting impulse, especially when using a large power motor, which will not only have a large impact on the power grid, but also have an impact on the drum itself; star-delta starting can reduce the instantaneous impact force, but when starting with material in the drying drum, starting failure is prone to occur. Utility Model Content
[0003] The utility model provides a dual-start drying drum, which can realize starting the drying drum in two ways: direct start or variable frequency start, so that the starting mode can be selected according to the actual situation, which can reduce the starting impulse and avoid the situation of starting failure.
[0004] The utility model is realized by the following technical solutions:
[0005] A double-start drying drum comprises a first power supply, a second power supply, a frequency converter, a control device, a plurality of motors, a start relay, a control relay, a first operation contactor and a second operation contactor, wherein the normally open contact of the control relay, the first normally open contact of the start relay, the normally closed contact of the second operation contactor and the coil of the first operation contactor are connected in series with the second power supply, the normally closed contact of the control relay, the normally closed contact of the first operation contactor and the coil of the second operation contactor are connected in series with the second power supply, the first normally open contact of the first operation contactor is connected between the first power supply and each motor, the first normally open contact of the second operation contactor is connected between the frequency converter and each motor, the frequency converter is bidirectionally connected with the control device, the coil of the start relay and the coil of the control relay are respectively connected with the control device, and the second normally open contact of the start relay and the second normally open contact of the second operation contactor are connected in series with the frequency converter. In this way, the drying drum can be started in two ways, namely, direct start or frequency conversion start, so that the start mode can be selected according to the actual situation, which can reduce the start impulse and avoid the start failure.
[0006] Furthermore, it also includes a first feedback relay, a second feedback relay and a DC power supply. The coil of the second feedback relay is connected in series with the second normally open contact of the first operating contactor and then connected to the second power supply. The normally open contact of the second feedback relay is connected in parallel with the two normally open feedback contacts of the inverter. The two ends of the coil of the first feedback relay are respectively connected to one end of the normally open contact of the second feedback relay and one end of the DC power supply, the other end of the normally open contact of the second feedback relay is connected to the other end of the DC power supply, and the normally open contact of the first feedback relay is connected to the control device. In this way, it is possible to timely feedback to the control device whether the motor is working normally.
[0007] Furthermore, it also includes an overload relay, multiple thermal relays and a fault relay, the coils of the multiple thermal relays are respectively connected between the frequency converter and each motor, the normally open contacts of each thermal relay are connected in parallel and in series with the coil of the overload relay and then connected to the second power supply, the normally open contact of the overload relay is connected in parallel with two normally open fault contacts of the frequency converter, the two ends of the coil of the fault relay are respectively connected to one end of the normally open contact of the overload relay and one end of the DC power supply, the other end of the normally open contact of the overload relay is connected to the other end of the DC power supply, and the normally open contact of the fault relay is connected to the control device, so that the control device can be alerted in time when the motor is overloaded or other faults occur.
[0008] Furthermore, it also includes an emergency stop button and an emergency stop relay. The coil of the emergency stop relay is connected in series with the emergency stop button and then connected to a second power supply. One end of the normally open contact of the emergency stop relay is connected to the second power supply, and the other end is respectively connected to the normally closed contact of the control relay and the normally open contact of the control relay, so that the motor can be quickly stopped in an emergency.
[0009] Furthermore, it also includes a circuit breaker, one end of which is connected to the first power supply, and the other end of which is respectively connected to the frequency converter and the first normally open contact of the first operating contactor.
[0010] Furthermore, the control device includes a PLC.
[0011] Furthermore, it also includes a switching button, which is connected to the control device to energize or de-energize the coil of the control relay.
[0012] Furthermore, it also includes a start button, which is connected to the control device to energize or de-energize the coil of the starter relay. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The utility model is further described in detail below in conjunction with the accompanying drawings.
[0014] Figure 1 This is the main circuit diagram of the utility model.
[0015] Figure 2This is a control loop circuit diagram of the utility model.
[0016] Among them, 1. the first power supply; 2. the frequency converter; 3. the control device; M1-M4, the motor; KY1, the coil of the start relay; KY11, the first normally open contact of the start relay; KY12, the second normally open contact of the start relay; KY2, the coil of the control relay; KY21, the normally open contact of the control relay; KY22, the normally closed contact of the control relay; KM1, the coil of the first operating contactor; KM11, the first normally open contact of the first operating contactor; KM12, the second normally open contact of the first operating contactor; KM13, the normally closed contact of the first operating contactor; KM2, the coil of the second operating contactor; KM21, the first normally open contact of the second operating contactor; KM22, the first normally open contact of the second operating contactor The second normally open contact of the second running contactor; KM23, the normally closed contact of the second running contactor; KA1, the coil of the first feedback relay; KA11, the normally open contact of the first feedback relay; KA2, the coil of the second feedback relay; KA21, the normally open contact of the second feedback relay; KA3, the coil of the overload relay; KA31, the normally open contact of the overload relay; FR1-FR4, the thermal relay; FR11-FR41, the normally open contact of the thermal relay; KX1, the coil of the fault relay; KX11, the normally open contact of the fault relay; KX2, the coil of the emergency stop relay; KX21, the normally open contact of the emergency stop relay; SB1, the emergency stop button; Q, the circuit breaker; U1, the second power supply. DETAILED DESCRIPTION
[0017] like Figure 1 and Figure 2As shown, the double-start drying drum includes a first power supply 1, a second power supply U1, a DC power supply, a frequency converter 2, a control device 3, four motors, four drums driven to rotate by the motors, a circuit breaker Q, a start relay, a control relay, a first operation contactor, a second operation contactor, a first feedback relay, a second feedback relay, an overload relay, four thermal relays, a fault relay, an emergency stop relay, and an emergency stop button SB1. The first power supply 1 is a three-phase AC power supply, one end of the circuit breaker Q is connected to the first power supply 1, and the other end is respectively connected to the power supply end of the frequency converter 2 and one end of the first normally open contact KM11 of the first operation contactor, the other end of the first normally open contact KM11 of the first operation contactor is respectively connected to the motor M1 to the motor M4 through the thermal relay FR1 to the thermal relay FR4, and the first normally open contact KM21 of the second operation contactor is connected between the output end of the frequency converter 2 and the thermal relay FR1 to the thermal relay FR4. The inverter 2 is bidirectionally connected to the control device 3. When the inverter 2 is running, the motor current information will be fed back to the control device 3 through the AO1 and GND points, and the control device 3 will feed back the frequency information set by the operator to the inverter 2 through the AI 1 and GND points. The coil KY1 of the start relay and the coil KY2 of the control relay are respectively connected to the control device 3. The switch button and the start button are set on the computer. The computer is connected to the control device 3 through a network cable. When the switch button is pressed, the control device 3 receives the signal and the coil KY1 of the start relay is energized. When the start button is pressed, the control device 3 receives the signal and the coil KY2 of the control relay is energized. The switch button and the start button are set on the computer, and the signal transmission between the computer and the control device 3 are all existing technologies. The second normally open contact KY12 of the start relay is connected in series with the second normally open contact KM22 of the second operation contactor and connected to the inverter 2. The normally open contact KY21 of the control relay, the first normally open contact KY11 of the starting relay, the normally closed contact KM23 of the second operating contactor and the coil KM1 of the first operating contactor are connected in series and connected to the second power supply U1. The normally closed contact KY22 of the control relay, the normally closed contact KM13 of the first operating contactor and the coil KM2 of the second operating contactor are connected in series and connected to the second power supply U1. The second power supply U1 is a 220V AC power supply.
[0018] The coil KA2 of the second feedback relay is connected in series with the second normally open contact KM12 of the first operating contactor and then connected to the second power supply U1. The normally open contact KA21 of the second feedback relay is connected in parallel with the two normally open feedback points (RA, RC) of the inverter 2. The two ends of the coil KA1 of the first feedback relay are respectively connected to one end of the normally open contact KA21 of the second feedback relay and one end of the DC power supply, and the other end of the normally open contact KA21 of the second feedback relay is connected to the other end of the DC power supply. The normally open contact KA11 of the first feedback relay is connected to the control device 3. The specific connection of this part with the DC power supply is the prior art.
[0019] The normally open contact FR11 of the thermal relay FR1 is connected in parallel to the normally open contact FR41 of the thermal relay FR4, and then connected in series with the coil KA3 of the overload relay and then connected to the second power supply U1. The normally open contact KA31 of the overload relay is connected in parallel to the two normally open fault points (TC, TA) of the inverter 2. The two ends of the coil KX1 of the fault relay are respectively connected to one end of the normally open contact KA31 of the overload relay and one end of the DC power supply. The other end of the normally open contact KA31 of the overload relay is connected to the other end of the DC power supply. The normally open contact KX11 of the fault relay is connected to the control device 3.
[0020] The coil KX2 of the emergency stop relay is connected in series with the emergency stop button SB1 and then connected to the second power supply U1. One end of the normally open contact KX21 of the emergency stop relay is connected to the second power supply U1, and the other end is respectively connected to the normally closed contact KY22 of the control relay and the normally open contact KY21 of the control relay.
[0021] In this embodiment, the control device 3 includes a PLC. The four motors need to be started and stopped at the same time, so the capacity of the inverter 2 needs to be greater than the sum of the four motors.
[0022] The working principle of the utility model is as follows:
[0023] Direct boot:
[0024] Close the circuit breaker Q, energize the coil KY2 of the control relay through the switching button, close the normally open contact KY21 of the control relay, and then energize the coil KY1 of the start relay through the start button, and close the first normally open contact of the start relay. In non-emergency situations, the emergency stop button SB1 does not work, then the coil KX2 of the emergency stop relay is energized, and the normally open contact KX21 of the emergency stop relay is closed, then the coil KM1 of the first running contactor is energized, so that the first normally open contact KM11 of the first running contactor connected between the first power supply 1 and the motor is closed, and the motor starts; in this case, the second normally open contact KM12 of the first running contactor is closed, so that the coil KA2 of the second feedback relay is energized. , that is, the normally open contact KA21 of the second feedback relay is closed, so that the coil KA1 of the first feedback relay is energized, and then the normally open contact KA11 of the first feedback relay is closed, that is, the control device 3 receives the signal that the motor is operating normally; when the motor is overloaded, a trip occurs in the thermal relays FR1 to FR4, and closed contacts appear in the normally open contacts FR11 of the thermal relay FR1 to the normally open contact FR41 of the thermal relay FR4, and the coil KA3 of the overload relay is energized, so that the normally open contact KA31 of the overload relay is closed, and the coil KX1 of the fault relay is energized, and then the normally open contact KX11 of the fault relay is closed, and the control device 3 receives the motor fault alarm information;
[0025] Frequency conversion start:
[0026] Close the circuit breaker Q, and use the switch button to de-energize the coil KY2 of the control relay. At this time, the coil KM2 of the second operating contactor is energized, and the second normally open contact KM22 of the second operating contactor is closed. Then, the coil KY1 of the start relay is energized by the start button, and the second normally open contact of the start relay is closed. In this way, the inverter 2 is started, and the coil KM2 of the second operating contactor is energized, so that the first normally open contact KM21 of the second operating contactor is closed, and the motor is also started; after the motor is started, the two normally open feedback points (RA, RC) of the inverter 2 are closed, so that the coil KA1 of the first feedback relay is energized, and then the normally open contact KA11 of the first feedback relay is closed, that is, the control device 3 receives the signal of normal operation of the motor; when a fault occurs, the two normally open fault points (TC, TA) of the inverter 2 are closed, so that the coil KX1 of the fault relay is energized, and then the normally open contact KX11 of the fault relay is closed, and the control device 3 receives the motor fault alarm information, which can be detected by the inverter 2, such as overcurrent, overvoltage, and phase loss.
[0027] Under direct starting, when the coil KM1 of the first operating contactor is energized, the normally closed contact KM13 of the first operating contactor is disconnected, which makes the coil KM2 of the second operating contactor not energized, that is, the first normally open contact KM21 of the second operating contactor connected between the frequency converter 2 and the motor will not be closed, that is, the motor will not be started in the variable frequency starting mode; under variable frequency starting, when the coil KM2 of the second operating contactor is energized, the normally closed contact KM23 of the second operating contactor is disconnected, so that the coil KM1 of the first operating contactor will not be energized, that is, the first normally open contact KM11 of the first operating contactor connected between the first power supply 1 and the motor will not be closed, that is, the motor will not be started in the direct starting mode, thus achieving interlocking to ensure that there is only one way to start the motor.
[0028] When there is no material in the drum, the inverter start-up method is selected to control the start-up of the motor to avoid the large impact on the power grid caused by the simultaneous start-up of four motors. At the same time, the low-frequency start-up is also a protection for the drum itself, and it will not be broken due to the impact of large current; when the drum suddenly stops due to a fault, if it is to be started again, there is material in the drum at this time. If the inverter is used for starting, it is easy to fail to start. Therefore, the direct start-up method is selected for starting, so the starting torque is large and the starting time is short, so that starting with materials can be achieved. In an emergency, the emergency stop relay can be de-energized through the emergency stop button SB1, and then the connection between the motor and the power supply or inverter 2 can be quickly disconnected.
[0029] The above is only a preferred embodiment of the present invention, and therefore cannot be used to limit the scope of implementation of the present invention. That is, equivalent changes and modifications made according to the scope of the patent application of the present invention and the contents of the specification should still fall within the scope covered by the patent of the present invention.
Claims
1. A double-start drying drum, characterized in that: The invention comprises a power supply, a frequency converter, a control device, a plurality of motors, a starting relay, a control relay, a first operating contactor and a second operating contactor. The normally open contact of the control relay, the first normally open contact of the starting relay, the normally closed contact of the second operating contactor and the coil of the first operating contactor are connected in series and then connected to the power supply. The normally closed contact of the control relay, the normally closed contact of the first operating contactor and the coil of the second operating contactor are connected in series and then connected to the power supply. The first normally open contact of the first operating contactor is connected between the power supply and each motor, the first normally open contact of the second operating contactor is connected between the frequency converter and each motor, the frequency converter is bidirectionally connected to the control device, the coil of the starting relay and the coil of the control relay are respectively connected to the control device, and the second normally open contact of the starting relay and the second normally open contact of the second operating contactor are connected in series and then connected to the frequency converter.
2. A double-start drying drum according to claim 1, characterized in that: It also includes a first feedback relay, a second feedback relay and a DC power supply. The coil of the second feedback relay is connected in series with the second normally open contact of the first operating contactor and then connected to the second power supply. The normally open contact of the second feedback relay is connected in parallel with the two normally open feedback points of the frequency converter. The two ends of the coil of the first feedback relay are respectively connected to one end of the normally open contact of the second feedback relay and one end of the DC power supply. The other end of the normally open contact of the second feedback relay is connected to the other end of the DC power supply. The normally open contact of the first feedback relay is connected to the control device.
3. A double-start drying drum according to claim 2, characterized in that: It also includes an overload relay, multiple thermal relays and a fault relay. The coils of the multiple thermal relays are respectively connected between the frequency converter and each motor. The normally open contacts of each thermal relay are connected in parallel and in series with the coil of the overload relay and then connected to a second power supply. The normally open contacts of the overload relay are connected in parallel with two normally open fault points of the frequency converter. Both ends of the coil of the fault relay are respectively connected with one end of the normally open contact of the overload relay and one end of the DC power supply, the other end of the normally open contact of the overload relay is connected to the other end of the DC power supply, and the normally open contact of the fault relay is connected to a control device.
4. A double-start drying drum according to claim 1, 2 or 3, characterized in that: It also includes an emergency stop button and an emergency stop relay. The coil of the emergency stop relay is connected in series with the emergency stop button and then connected to a second power supply. One end of the normally open contact of the emergency stop relay is connected to the second power supply, and the other end is respectively connected to a normally closed contact of a control relay and a normally open contact of the control relay.
5. A double-start drying drum according to claim 1, 2 or 3, characterized in that: It also includes a circuit breaker, one end of which is connected to the positive pole of the power supply, and the other end of which is respectively connected to the frequency converter and the first normally open contact of the first operating contactor.
6. A double-start drying drum according to claim 1, 2 or 3, characterized in that: The control device includes a PLC.
7. A double-start drying drum according to claim 2 or 3, characterized in that: It also includes a switching button, which is connected to the control device to energize or de-energize the coil of the control relay.
8. A double-start drying drum according to claim 1, 2 or 3, characterized in that: It also includes a start button, which is connected to the control device to energize or de-energize the coil of the starter relay.