Application of the hottest delta frequency convert

Application of delta inverter in cold rolling mill

at present, the main product types of cold rolling series equipment include: cold rolling torsion series equipment, straightening machine series equipment and cold rolling ribbed bar production series equipment. Among them, the cold-rolled ribbed steel bar equipment is a steel rolling production line, and the material is the original rolled steel bar. After being processed by the production line, the surface is embossed with ribs and cut by fixed length. First, it is stretched by direct torque control through the primary motor, then stretched by the secondary motor and embossed on the surface, then stretched by the tertiary motor, and finally cut at the end of the production line. The primary motor was previously operated by the torque motor with short service life and other problems. Considering the many advantages of frequency converter control, the frequency converter was used to replace it for torque control. In view of the space constraints of the production line, it is not suitable to install tension frame sensors between the primary and secondary motors for feedback, and the open-loop torque control of V series frequency converter is needed for direct drive

1. System architecture:

1) the production line process of cold rolling equipment is as follows:

rebar raw materials → vfd370v43a torque control (primary motor) → vfd550b43a speed control (secondary motor) → vfd055b43a speed control (tertiary motor) → fixed length cutting → completion

2) inverter configuration: one vfd370v43a, vfd550b43a, vfd055b43a respectively

3) vfd370v43a external electrical control part of frequency converter:

a, a potentiometer is connected with + 10V, AVI and ACM to adjust the torque command

b, a button to switch the speed/torque mode, and in the speed mode, this button realizes the terminal command of inching frequency at the same time

c, short circuit AVI and AUI terminals

d, short circuit MI1 and mi2 terminals

2. Process requirements:

in the production line process of cold rolling equipment, vfd370v43a, the frequency converter used to drive the primary motor (driven), carries out direct torque control, and pulls the reinforcement forward in the production process. The given torque is a suitable value; When the secondary motor (active) runs, the primary motor will follow the secondary motor in the system to replace the torque motor previously used. And in the actual use process, when a roll of reinforcement is used, it is required to realize inching operation and feeding in the speed mode when replacing materials, so that the reinforcement can smoothly pass through the mechanical part of the equipment. In addition, vfd037v43a of frequency converter is required to drive its heavy load independently within the range of maximum torque command. For example, the load is replaced with reinforcement with a larger diameter. Aluminum spot welder

3. Commissioning steps:

1). Optimize the parameters of the primary motor and set the corresponding parameters:

00-10 = 4 (torque control mode)

00 － 20 = 2 (external analog quantity of frequency command)

03-00 = 1 (AVI is the unit fixed frequency/torque command for 80 of them to produce degradable plastics or blends)

at this time, turn the external potentiometer and input a more appropriate torque for direct torque control. At this time, the reinforcement does not move forward under this torque. Only when the second stage stretching motor runs at the speed, the first stage stretching motor drives the reinforcement to move forward under the torque mode

2). Realize inching operation in speed mode

when the external terminal mi2 is switched to speed mode (02-02 = 32 torque speed mode switching),

set the external terminal MI1, 02-01 = 1 (multi-stage speed command I); 04 － 00 = 1 (the speed of the first section is 1Hz)

at this time, the multi-stage speed frequency 1 can operate normally in the speed mode. With the load, the effect is also good

3). Test whether it can drive a larger load in the direct torque mode

due to the thickness of reinforcement materials, after increasing the load, when the motor directly gives torque, gradually rotate the potentiometer, increase the torque command size, and observe the motor's response. To observe whether the load can be pulled before the torque increases to full torque. The setting parameters are as follows: 06-12 = 250 (torque limit is set to 250%)

when the potentiometer rotates to the full position, the torque command is the maximum value at this time, but the load does not move; Set 03-02 = 8 (AUI analog function is torque compensation); The effect is poor when adjusting AUI analog quantity alone, and it is effective when adjusting AVI and AUI analog quantity at the same time. Because the external circuit only allows one potentiometer analog quantity input, the AUI and avi terminals are short circuited. When the external potentiometer rotates, the torque command and torque compensation are gradually increasing. When it increases to a certain value, the primary motor drives the load to run

4）、 Parameter setting:

the final parameter setting of vfd370v43a, which controls the primary motor, is as follows:

00 － 10 = 4. The control mode is torque control

00 － 20 = 2. The specified frequency source is external analog input

01 － 00 = 50. The maximum operating frequency is 50Hz

01 － 01 = 50. The rated frequency of the motor is 50Hz

01 － 02 = 380. The rated voltage of the motor is 380V

02 － 01 = 1. The multi-function input terminal MI1 is multi-stage speed command I

02 - 02 = 32 function input terminal mi2 is torque speed mode switching

03-00 = 1 Analog avi input is frequency/torque command

03-02 = 8 analog AUI input is torque compensation

04-00 = 1 first segment speed is 1Hz

05-02 = 16.9 motor no-load current is 16.9a

05-06 = 151.8 motor R1 it is also the first 3D printable medical material developed in Korea, 151.8m Ω

05-07 = 166 motor R2 is 166m Ω

05 － 08 ＝ 471 8. Motor LM parameter 471.8mh

05-09 = 29.9 motor LC parameter 29.9mh

05-29 = 200, the oscillation compensation factor is 200

06-12 = 250, and the torque limit is 250%

4. Debugging summary:

1. Delta inverter uses direct torque mode to replace torque motor, which has superior performance and good effect

2. The production line operates stably and the maintenance cost is greatly reduced

3. The quality of the produced products is very good, and the end users respond well