A frequency converter is a device that converts power to other frequencies of power supply. The power frequency of our country is 50Hz, in the field of motors, in order to change the speed of the motor, or other performance changes, many motors choose inverter power supply.
Inverter is a kind of conversion equipment used with inverter motor, from the configuration of the line, the inverter is between the motor and the power frequency power supply, and the motor with different load characteristics should match the inverter with different performance.
The relationship between the voltage and frequency of the inverter
In the case of an asynchronous motor, the torque of the motor is the result of the magnetic flux of the motor acting together with the rotor current. With the extra frequency as the boundary, when the frequency of the power supply is reduced, if the input voltage of the motor is insisted on unchanged, the magnetic flux of the motor will be full, and the motor winding will be burned when it is severe. For this reason, when the power supply frequency is reduced, the input voltage of the motor should be lowered together, and the magnetic flux of the control motor is unchanged as the criterion, which is generally used more in the load of fans and pumps.
For power frequency motors, if the voltage is lower than the additional voltage, the current of the motor will increase a lot if the same power is output, especially for the motor running on the temporary line, and the winding incineration problem caused by this is particularly many. Then about the motor powered by the inverter, when running at low speed, if the same power is required to be output, that is, the constant power operation condition, there is also the problem of current increase, but if it is a constant torque operation condition, the current of the motor will not change much.
The control key of the 60Hz motor is the power frequency 50Hz power supply experiment
Regarding the newly built experimental institutions, most of them are equipped with variable frequency power supplies, which can be tested according to the practical frequency of the motor, but about some old experimental equipment or some repair units, they may not have the experimental conditions for frequency conversion, and how to experiment about the 60Hz motor?
According to the theoretical inference of this paper, when the power frequency 50Hz power supply experiment is selected, the method of voltage drop should be selected, and the voltage experiment should be applied according to the calculated value of the motor additional voltage divided by 1.2.
|
More on that
|
The basic method and steps of inverter debugging - power inverter
1. No-load energizing test of inverter
1. Ground the grounding terminal of the inverter.
2. Connect the power input terminal of the inverter to the power supply through the leakage maintenance switch.
3. Check whether the factory display window of the inverter is normal, if it is incorrect, it should be reset.
|
|
Introduction of LS power products
1. Power-related products: medium, low and high voltage electrical products;
(1) Low Voltage Products: Molded Case Circuit Breaker, Air Circuit Breaker, LS Contactor & Overload Relay, Miniature Circuit Breaker, Dual Power Automatic Transfer Switch, Intelligent Motor Protector, Manual Motor Starter, Surge Protection ...
|
|
Analysis of the working principle of the inverter - LS power generation
The rectified DC voltage of the rectifier contains the pulsating voltage of the power supply 6 times the frequency, and the pulsating current generated by the inverter also changes the DC voltage.
The main power is the power replacement part of the power supply for the asynchronous motor voltage regulation and frequency modulation power supply, and the main power of the inverter can be roughly divided into two ...
|
|
Fatal failure of LS power terminal block
From the point of view of application, the function that should be reached is: it is necessary to conduct the local area where the touch part should be conducted, and the touch is reliable. If the insulating part should not be conducted, it is necessary to insulate it firmly. There are three common fatal problems in terminal blocks:
...
|
|
Power production PLC installation and wiring skills
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 line, control line and PLC power line and I/O line should be separated from the wiring, barrier transformer and PLC and I/O should be selected ...
|
|
Introduction of plc inverter - LS power generation
Because the imported products of the inverter brand have their own PLC function, they mainly play an important role in the control effect of mechanical equipment, and play an important role in the equipment, which can regulate the operation and control of the machine and meet the requirements of users.
It should be scale
pLC ...
|
|
LS GTH, GTK series thermal relay models
Thermal Overload Relay GTH-22
GTH series: GTH-22, GTH-40, GTH-85, GTH-100, GTH-150, GTH-220,
GTH-400、GTH-600、GTH-12M、GTH-12MH、GTH-12M、GTH-MH
GTH series: GTH-22, GTH-40, GTH-85 ...
|
|
The selection principle of AC contactors - LS produces electricity
1. The voltage level of the AC contactor should be the same as the load, and the type of contactor should be suitable for the load.
2. The accounting current of the load should be less than or equal to the additional working current of the contactor.
The turn-on current of the contactor is greater than the starting current of the load, and the breaking current is greater than the load ...
|
|
An integral part of an electrical solid state relay
Solid state relays consist of three parts: the input circuit, the barrier (coupling), and the output circuit.
Input Circuit:
According to the different categories of input voltage, the input circuit can be divided into DC input circuit, communication input circuit and AC-DC ...
|
|
The internal accessories component of the power production circuit breaker
1. Auxiliary contact: the contact mechanically linked with the main circuit of the circuit breaker and the closing mechanism is mainly used for the display of the circuit breaker and the closing status, and is connected to the control circuit of the circuit breaker through the opening and closing of the circuit breaker to control or interlock its related electrical appliances. For example, output to signal lights, relays, etc.
|
|
LS inverter classification
LS Denden's low-voltage inverters provide optimal speed control in a variety of industrial sites, and are solutions that can demonstrate the completion of an automation system and have an epoch-making power saving effect. It includes four types of products: IGXA; S100; IS7; C100 series.
...
|
|
Why can't the inverter be equipped with a leakage protector?
When using an inverter, a leakage maintainer must not be used. This is a major criterion for 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 ...
|
|
Specification steps for the safe operation of generator sets – power generation
Standardized procedures for safe operation of generator sets
1. Preparation before starting
(1) The operators of the computer room should abide by the safety operation procedures, wear work clothes and insulated shoes, and the crew should have a clear division of labor.
(2) Check whether the flywheel and part of the generator are not defective. ...
|
|
Switching analysis and synchronous control of inverter - LS power generation
AC asynchronous motors are widely used in all walks of life, and frequency converters and power frequency power supplies are often required to switch in the selection of frequency conversion speed control system. The primary types of switching are: fault switching and multi-machine system switching. In the process of operation of many production machinery, the motor is not allowed to stop ...
|
|
The impact of power quality problems on frequency converters - electricity production
(1) Excessive voltage error will increase the loss of electrical equipment, shorten the life, and work abnormally, which will damage the stability of the synchronous operation of the power system, the stability of the voltage and the economic operation of the power grid, and will cause the inverter system to report overvoltage fault or undervoltage fault.
...
|
|
The main functions and functions of LS power production PLC
1. For sequential control: sequential control is based on the current and pre-historical conditions of the input switch, and produces the required switching output, so that the system can work in a certain order. This is the basic manipulation of the system. It is also a common manipulation in discrete production processes.
...
|
|
The size of the contactor is selected by the type of contactor - LS produces electricity
1. Select the corresponding category of contactor according to the control object, operation times and application category of the contactor.
2. Select according to the rated voltage of the line at the application location.
3. Select the rated current of the main contact of the contactor according to the load capacity.
4. About the voltage level of the lead coil ...
|
|
LS MASTER-K120S series PLC features and advantages
(1) This series is divided into two types: economic type and standard type, which can meet the requirements of different customers:
Economical: 10/14/20/30 points (10/14 points with 2 built-in analog potentiometers), up to 70 points.
Standard type: 20/30/40/60 point DR/DRT (2-axis position ...
|
|
Analysis of the fault problem of LS power terminal block
From the point of view of application, the function of the terminal block should be achieved: it is necessary to conduct the local conduction of the touch part, and the touch is reliable. The insulating part should not be conducted, and it is necessary to insulate it firmly. There are three common forms of fatal problems in terminal blocks:
...
|
|
Energy-saving method of ventilator inverter - LS power generation
high-power
Although some inverters are fan type inverters, but it is a low-power fan inverter, such an inverter does not have the effect of energy saving, and it is necessary to achieve energy saving must be a high-power inverter, in addition to the high-power fan inverter, it is necessary to meet its ...
|
|
Contact
working hours
