Inverters are increasingly popular for speed control for all types of machinery and equipment in industry and construction. Let’s learn more about the common applications of the inverter in the following article.
Water pumping
This is the most popular application of the inverter.
Inverter for level 2 pump (flow control)
In the traditional system, the pressure and flow of the pump are controlled by a multi-speed motor, in and out valve or reflux system. All of these methods waste a lot of energy, causing mechanical shock, reducing system life and increasing pipe depreciation.
Inverter series used in the water pump system
The inverter is used to regulate the speed of the pump, which can run at the flow/pressure option. Since then, it helps increase efficiency and save energy. At the same time, the inverter also helps the system to operate smoothly, reduce maintenance costs, repair, reduce pipeline losses, and increase the life of water pumping systems.
Water supply for buildings
Before the appearance of the inverter, if you want to supply water for high-rise buildings, people have to pump water to the roof water tower to distribute to the entire building. At the same time, it is necessary to adjust the pressure of each floor by means of regulating and reducing pressure. The disadvantage of this system is that it increases building structure, energy consumption, large costs for pressure reducing devices, high requirements for pipe systems …
The use of motor drive inverters to provide the required load will greatly save electricity. Not only that, but it also helps reduce investment costs when not building a water tower.
Inverter for level 1 pump (no flow control)
Level 1 pumps are usually controlled by a simple switching method. Usually, the pump capacity is chosen very large compared to the needs of the system. In many cases, the pump usually runs idle, increasing the pressure and pipe loss. Besides shocking when operating … To overcome many of these disadvantages, people often open the exhaust valve or peel the impeller. However, these methods are only intended to overcome the over-pressure of pipes without overcoming other disadvantages.
The use of inverter motor control allows pressure control, flow options, soft start, optimization of engine operation, power saving for the system …
Sucking/Pushing Fan
Sucking/Pushing Fans are commonly used in areas such as vacuuming, oven fans, ventilation … To control the amount of wind needed, people often use a multi-level motor control system, control valves … The disadvantages of this method are similar to pump systems.
The use of inverter motor control also allows pressure control, soft start, optimization of engine operation, power saving for the system.
Air Compressor
Conventional air supply control mode operates in a closed / cut mode. This mode controls the inlet air through the inlet valve. When the pressure reaches the upper limit, the inlet valve is closed. The compressor will go into idle operation. When the pressure reaches below the lower limit, the inlet valve opens. At this time, the compressor will go into the load operation state. The rated power of the motor is selected according to maximum demand. Normally this power is designed to be overloaded. The main starting current, the motor operates continuously when no load consumes a large amount of electricity.
The inverter used in air compressors
Motor speed control mode by inverter operates as follows: The air supply only needs to meet the consumption of gas. Therefore, the gas supply system can achieve the highest efficiency and save electricity.
Conveyor
The conveyor transmission system has a very large starting torque. The inverter can create high starting torque but still ensure the starting current within the allowable limit of the net. The ability to start and stop gently is achieved by controlling the amount of time needed to accelerate/decelerate.
The inverter used in conveyors
Benefits of using inverters for conveyors
- Energy is saved when running the engine at a speed consistent with the load requirements. High engine power factor. In addition, in the case of a conveyor with an inertial run (downward slope), the conveyance of the conveyor can be converted into electrical energy to return the grid to the regenerative brake inverter.
- When multiple motors are used, the speed can be synchronized. Besides the load can be shared between engines.
- Can compensate for slip speed, detection of torque, speed detection. Along with that is the function to increase the motor torque when the load torque increases. This function helps the conveyor speed is always stable.
- Control the start and stop process correctly on the conveyor system.
Lifting equipment
Lifting systems in Construction and Industry often face technological problems. These problems have not been handled well in the traditional design process. Eg:
- It is difficult to control the running speed.
- It only runs at a fixed and low speed.
- Acceleration/deceleration easily leads to mechanical shock
- Stop incorrectly when loading changes, unsafe …
The inverter used in lifting equipment
The inverter has positioning control, torque and braking to make applications such as cranes and pa-steering possible by using AC motors. Inverters for lifting equipment have regenerative braking systems and energy grids. This type ensures safety and power saving.
In the crane system moving heavy bales, the control system consists of 2 structures. It is the control of lifting and controlling moving girder. The control of moving girder crane is carried out by 2 motor and power source and close / cut simultaneously. This structure is located at the foot of the girder. Two motor activities cause some harm such as: Create a tendency to twist the beams; causing high energy consumption due to high starting current; causing a drop in the grid voltage when starting.
Solutions
The solution to overcome these disadvantages is to use an inverter to control 2 motors moving girder. This solution brings practical benefits. Eg:
- Soft start, stable power network quality.
- The heat loss on the wire is reduced. Overcoming the phenomenon of pressure drop on the grid.
- The process of starting and stopping the smooth load, reduced noise, increasing the life of the motor and mechanical structures.
- Increase in safety.
- Energy saving.
Planer
In steel production, conventional rolling mills use AC motors. The reversible rolling machine uses a DC motor. Accurate control of engine speed according to technical requirements is required. Traditional wire tractors usually do not adjust the speed according to the tension. This results in products that may not guarantee quality when traction changes.
Using inverter motor control rolling scissors will fully and accurately meet the drive requirements of production technology. AC inverter for AC motors and DC converters for DC motors.
Injection machine.
For traditional injection molding machines using fixed hydraulic pumps, the capacity is usually calculated at the maximum load condition. An adjustable valve is used to change flow and consumption pressure. A large proportion of energy is consumed through the valve in the form of pressure difference by the overflow. So the energy is very huge.
The inverter used in injection machines
If the control system with the inverter can automatically adjust the speed of the oil pump motor according to the actual load requirement (pressure and flow) in accordance with each stage. Then the energy consumption will reach the lowest level.
Rolling/ releasing machine
The biggest requirement for these types of machines is to stabilize the tension, ensuring regular roll/release. Particularly required with roll/release materials, film, sheet … (pull wire, roll, print, coated …). The use of inverter ensures the coiling/release of the two motors, stabilizing the tension between the two ends. At the same time, it is possible to actively adjust the speed when it is necessary to use release modes when changing the material size, strain requirements.
Hopefully, the knowledge about the application of inverter in the industry has helped you better understand this device. Don’t forget to read the interesting information about the inverter in the next article.
