First, the process requirements of the grinding machine:
The grinding machine is a kind of textile machinery, and its function is to polish the dyed cloth to improve its added value, which is an important process in the printing and dyeing process. The traditional driving method is driven by a DC motor, and the ceramic plate resistance linked with the lifting rod is used for feedback to adjust the excitation current of the DC motor to achieve the purpose of speed synchronization. However, in the printing and dyeing industry, the equipment works in an alkaline and humid air environment for a long time, and the DC motor structure has a high failure rate and a large amount of repair during use, which sometimes seriously affects production. With the many applications of frequency conversion governor in this industry, its synchronous speed regulation has gradually been recognized and accepted by people for its high precision, high reliability function, and simple peripheral architecture.
2. Difficulty in control:
The inverter control system system has a high running speed, stable tension, good follow-up motor speed, and insists on synchronization between motors.
3. Program Description:
The following is our inverter control scheme for the grinding machine of a machinery factory in Zhangjiagang, Jiangsu.
1. The sanding machine is divided into two parts: sanding and traction, the control of the sanding area is relatively simple, according to the needs of customers, we set the speed of the touch screen, and the PLC is driven by RS485 (LS-BUS) communication to drive the inverter to adjust the motor speed online, and can be selected at will for forward rotation and rotation.
2. The following will be a specific explanation of the tension part of synchronous control. The whole traction mechanism is composed of 4 motors, in order to make our inverter more capable of controlling tension, a tension roller is installed in front of traction roller 2 and traction roller 3, the tension of cloth is detected by the tension sensor through the tightness of the cloth, the A/D value output by the tension transmitter is sent to the A/D module of the PLC, and after PID operation, the set data (0-4000) is transformed to 0-5000, and the frequency of the given inverter is communicated through RS485 (LS-BUS mode). In this way, the inverter runs smoothly, quickly makes up for the difference in the range, and adheres to constant speed and constant tension.
3. In terms of the overall speed conditioning, we set the starting speed and carry out the control and twist of gradual acceleration, which can be adjusted through the touch screen.
4. Conclusions:
The successful application of LS inverter in the grinding machine has improved the control function of the grinding machine, and achieved constant tension and constant speed control, from the beginning of debugging to the present half a year, whether it is the operation status of the inverter or the control function of the system, it has always been very stable, and the customer is very satisfied with this!
|
More on that
|
DC reactor for inverter and design calculation - LS power generation
The DC reactor for the inverter is also called the flat wave reactor, which is connected in series in the DC bus (terminals P1 and P+). The main thing is to reduce the higher harmonic component of the input current and improve the power factor of the input power supply (to 0.95). This reactor can be used at the same time as the AC reactor, and the inverter has high power ...
|
|
What are the determinants of the performance of LS inverters?
The quality of the control circuit determines the function of the LS inverter.
The function of the DC central circuit is to smooth the output of the rectifier circuit to ensure that the inverter circuit and the control power supply can obtain a high-quality DC power supply. When the whole ...
|
|
The difference between input reactor and output reactor – LS produces electricity
The rectifier part of the general inverter selects the diode uncontrollable bridge rectifier circuit, and the middle filter part selects the large capacitor as the filter, so the input current of the rectifier is actually the charging current of the capacitor, and the harmonic component is relatively steep and steep.
|
|
The matrix alternating control mode of the inverter - LS power generation
VVVF frequency conversion, vector control frequency conversion, and direct torque control frequency conversion are all one of the AC-DC-AC frequency conversion. One of the disadvantages is that the input power factor is low, the harmonic current is large, the DC circuit needs a large energy storage capacitor, and the regenerative energy cannot be reflected back to the grid, that is, it cannot carry out four-quadrant operation.
|
|
The five stages of mastery of PLC technology
One. Logical stage
The so-called logical stage is to be able to complete the general logical planning in the relay system, since it is a relay system, so the knowledge of power drag is the foundation of this stage. I personally summarize that the root of learning the relay system lies in the word "grab", the relay system ...
|
|
PLC installation and wiring skills - LS power generation
The PLC should be kept away from strong disturbance sources such as electric welding machines, high-power silicon rectifier equipment and large-scale power equipment, and cannot be installed in the same switch cabinet as high-voltage electrical appliances.
Power cables, control cables, and PLC power cables and I/O cables should be separated from the wiring ...
|
|
Introduction to the matching of LS power inverter loads
1. Square torque load
Fan and pump loads are the most widely used equipment in industrial sites, and frequency converters are used in this type of load. It is a square torque load. In general, inverters with U/f=const control mode can be satisfied with the ...
|
|
Cycloidal reducer transmission system testing - LS power production
With the support of data processing, signal analysis and computer skills, the transmission system uses dynamic error detection equipment, starting from the measurement of time domain error information, and the internal dynamic test of the transmission system should include the following aspects.
...
|
|
Meaning and classification of LS Electronic Motor Relay (EMPR).
The Electronic Motor Relay (EMPR) is a digital motor maintenance relay with an MCU that has a compact and compact form factor that can be combined directly with a contactor. Through the implementation of real-time data processing, high reliability and high precision can be completed, and it can pass through phase loss, reverse, unbalance, stalled rotor, connection...
|
|
The reason why the inverter cannot be equipped with a leakage protector
When using inverters, leakage protectors must not be used. This is a major principle of the use of frequency converters.
Some users choose the corresponding leakage protector for the inverter when using the inverter. *The result is: the inverter moves together, the leakage protector acts, and the system can't ...
|
|
Single-table driver for HLP2B
|
|
Key points of LS power BKN circuit breaker design
(1) The cooperation between the circuit breaker and the circuit breaker should consider the instantaneous trip device action value of the superior circuit breaker, which should be greater than the maximum expected short-circuit current at the outlet end of the lower circuit breaker.
|
|
Inverter harmonic calculation method - LS power generation
1. Method 1
Method 1: Fourier transform to obtain the amplitude and phase of each harmonic of voltage and current, calculate the active power of each harmonic according to P=√3UIcosφ, and add the active power of all harmonics to obtain the harmonic power.
Method 2: Measure the total active work ...
|
|
The difference between voltage inverter and current inverter - LS produces electricity
For example, the operating principle of voltage inverter is mainly to regulate the voltage source, and the voltage source regulates the current to achieve the role of conditioning, while the current inverter is to directly regulate the current to achieve the role of conditioning.
...
|
|
Features of LS SUSOL series circuit breakers
Features of SUSOL series circuit breakers:
It can be used as the main switch of electrical equipment, and the limit breaking ability is high, Icu=Ics
Modular construction of circuit breakers: Tripper replacement (TS series) can be combined in a variety of combinations, such as ...
|
|
Inverter exception handling method - LS power generation
1. The working temperature of the inverter is high
1. Check whether the ambient temperature of the inverter is too high;
2. Check whether the cooling fan inside the device is working properly;
3. Check whether the ventilation pores and mask grilles are blocked;
4. Check if the load is too heavy.
...
|
|
Inverter circuit board repair and drawing-free maintenance method - LS power generation
1. Be "confident"
It is necessary to fully understand the principles of some typical circuits and be familiar with them. Guangzhou Kewo Training Center believes that drawings are dead, and the thoughts in the head are alive, able to make analogies, able to reason, and able to touch analogies. For example, switching power supply is always inseparable from ...
|
|
Why can't the inverter be equipped with a leakage protector - power generation
When using an inverter, a leakage maintainer must not be used. This is a major principle of the use of frequency converters.
Some users choose the corresponding leakage maintainer for the inverter when using the inverter. *The result is: the inverter moves together ...
|
|
The power of LS power inverter is selected
The relationship curve between the load rate β and the power η of the inverter can be seen: when β = 50%, η = 94%; When β = 100%, η = 96%. Although the β has doubled, the η change is only 2%, but it is also considerable for medium to high power (a few hundred kilowatts to several thousand kilowatts) electric motors. The system power is equal to the inverter power ...
|
|
The working principle of the LS power production module
When the LS power generation module is put into operation, its working process is generally divided into three stages, namely input sampling, user program fulfillment and output rewriting. The completion of these three phases is called a scan cycle. During the entire operation, the PLC's CPU repeatedly performs the upper ...
|
|
Contact
working hours
