light industry

First, the inverter in the dyeing and finishing industry development trend
For the dyeing and finishing industry, power consumption is the main part of the cost of production, and VAT is one of the major energy consuming equipment in yarn dyed, with the development of variable frequency control technology, on the flow pressure difference frequency control has been in the dyeing and finishing industry are widely used. Adopting frequency conversion energy-saving energy-saving transformation of VAT has become the dyeing and finishing industry to reduce dyed yarn in energy costs, the most effective way to improve the competitiveness of their products. The application of AC frequency converter in the VAT, has an important significance for reducing the waste of energy.

 

Two, the main loss in the process of VAT
The dyeing process is a process of periodic operation, which is the time control of the inner flow and the outflow. Mainly depends on its internal and external flow reversing commutator; and the yarn flow depends mainly on the main pump. First for the hardware loss. Ordinary VAT main pump with the original Y -] reduced voltage starting, the starting torque and starting current, the main pump to speed up the aging and the commutator of the accelerated wear. Improve the maintenance cost and the waste of energy. The second is the overflow loss. With different yarn in the process, the process required temperature, flow rate, pressure difference, for the main pump motor. The VAT in the dyeing process of load is in a state of change. And flow rate of the pump is designed according to the required maximum flow, provide the owner pump motor at a constant speed of pressure and flow, when the per yarn pump flow is less than the maximum flow color pigments, but through the every pound of yarn, the no in the shortest time to add color, this part of the energy lose. Third for throttling loss. When the water through the mouth of the commutator commutator will have a certain flow and pressure, increase the torque of the electromagnetic valve. At the same time, due to the severe long-term water full circulation flow and reversing device of mechanical friction, resulting in sealing ring temperature is too high, commutator noise, mechanical life shortening is not good phenomenon. Fourth for design margin loss. Usually in the design, taking into account the common character, design with maximum capacity is based, so VAT as the main pump motor design capacity than it actually needs much higher, "big car Mara" phenomenon, resulting in the waste of energy.

 

Three. The energy saving principle and control system of flow differential pressure control inverter
First speed regulation and energy saving. According to the dyeing of yarn process requirements, the original master cylinder injection material pipe is changed into a flow controller converted 4-20mA current signal and in PLC Analog input as the inverter frequency for a given signal, PLC on the of real-time sampling and through the PID operation, so that the output to the inverter frequency rate with flow controller, the analog signal into a linear change; in after a given number of pounds size through the PLC operation, the size of the pressure and flow will automatically adjusts the rotate speed of the motor, thereby reducing the output power of the motor, reversing solenoid valve in the installation of reversing switch in place, has ensured that reversing solenoid valve full action in place. The internal and external current commutation will automatically reduce the rotating speed according to the change of the commutation switch, and the speed of the motor and the reversing valve can achieve the minimum degree of energy loss in the whole load range. Second cost reduction, easy to operate. The master cylinder original level controller and a magnet signal into analog signal from controller to achieve control of the level of water. And the man-machine interface is added to view the real-time water level of the master cylinder. Has been exempt from the operation of the main cylinder water caused the accident. The water level controller of the material cylinder is removed, and the original analog signal controller is used to control the level of the water level, and the maintenance cost and the production cost are reduced. Third improve power factor. No power will not only increase the heat loss and equipment, mainly because of the decrease of power factor leads to a decrease in power grid. It is known that the greater the power factor, the greater the active power is. Common main pump cos Phi values between 0.6 to 0.8, and the use of variable frequency speed regulating device, due to the AC filter capacitor compensation, making cos phi = 1, so as to reduce the reactive power loss, increasing the active power of the grid. Fourth soft start energy saving. Due to the original motor for direct start or Y /] start, starting current equal (3-7) times the rated current, it will cause serious impact on Electrical and mechanical equipment and power grids, but also increase the network capacity requirements, the large current generated when starting and vibration is extremely unfavorable to the service life of the equipment. After the use of the frequency conversion energy-saving device, the use of frequency converter soft start function will make the starting current starting from zero, is limited to a maximum acceleration in the frequency converter set in current amplitude level limit, generally not more than 1.2 times the rated current, reducing the impact on the grid and grid capacity requirements, and prolongs the service life of the equipment.