Community of green energy, renewable power, electrical machinery, automation, process control...

Our blog focus on green energy, renewable energy for a long time. Since our company is in the line of frequency inverter, variable speed drive, servo motor and drive, motor soft starter and so on, we decided to come back to this matter.

And some people worldwide has participated in our community for these topics. But we think it's not enough. We want more people to join our community and take this blog as their own place to talk, share their ideas and experiences with each other.

So what should we do in the next step? Please come here and leave your advices and comments on this community.

Need more quality content?

Need more articles about solar power?

Need more about wind energy?

Or need more of bioenergy?

Want to participate in the survey?

or others?

Just come and leave your messages here. We will value your voice here. And people worldwide will value your voice too!

The types of motors that ac drives control are normally operating at constant speed. Enabling the user to control the speed of motor potentially gives ac drive various benefits in terms of process control, system stress and energy savings.

Advantage of frequency inverter for process control:

controlling the process output to match the need; synchronising different parts of the main process to secure smooth flow between subprocesses; easily changing the setup when the process requirements change.

Advantage of frequency converter in system stress:

Reducing the start-up current, which allows use of smaller fuses and supply connections and reduces peak loads on the electrical network; Reducing the mechanical shock in start and stop situations.

Advantage of ac drive for energy conservation:

One of the most important tasks in oil refinery management is cost reduction, particularly the technological component of processing costs. Power comsumption in oil refinery management is large. Application of frequency converters (ac drives) is one way to achieve this goal because the advantage of applying frequency inverters (Variable frequency drives) is for energy conservation.

Application of frequency converters helped to significantly improve the quality of air cooler control by means of regulation of the fan rotation speed by eliminating negative factors which affected the operation of air coolers due to ambient temperature fluctuations. The dynamics of air cooler power consumption has also changed.

Statistical Process Control (SPC) is an effective method of monitoring a process through the use of control charts. Much of its power of Statistical Process Control (SPC) lies in the ability to monitor both process center and the variation about that center.

By collecting data from samples at various points within the process, variations in the process that may affect the quality of the end product or service can be detected and corrected, thus reducing waste as well as the likelihood that problems will be passed on to the customer. Statistical Process Control (SPC) has an emphasis on early detection and prevention of problems.

Below is an example to illustrate statistical process control.

A commonly used control device called a programmable logic controller (PLC), is used to read a set of digital and analog inputs, apply a set of logic statements, and generate a set of analog and digital outputs. For example, the room temperature would be an input to the programmable logic controller (PLC). The logical statements would compare the setpoint to the input temperature and determine whether more or less heating was necessary to keep the temperature constant. A programmable logic controller (PLC) output would then either open or close the hot water valve, an incremental amount, depending on whether more or less hot water was needed. Larger more complex systems can be controlled by a Distributed Control System (DCS) or SCADA system.

In practice, process control systems can be characterized as the following forms:

1. Discrete

2. Batch

3. Continuous

I hope to talk with you here for Industrial automation, Building automation, Motion Control, Motors & Drives, Process control.

Please comments on my articles for automation, process control and so on. Your comments for my articles will make me glad and write more.

And there are many famous brand of frequency inverters (ac drives) in the world. Famous brands of this item include ABB, Simens, Danfoss and some brands from Japan. These brands are used widely in the world. But do you know? Today, many famous brands of inverters have decided to manufacture their frequency inverters (ac drives) in China. Why? Why do they decide to manufacture frequency inverters in China? The reason is the same as that many famous companies manufacture their shoes, their comsume electronics in China. Because the cost of the labour in China is so cheap!!

So these famous brands of frequency inverters (ac drives) closed their factory in Europe, USA or other areas. Or they reduced the manufacturing of frequency inverters (ac drives) in Europe, USA or other areas just to save the cost. Then they can competite with the very cheap price.

Variable speed drives (VSDs) are used for two primary reasons:
1. To improve the efficiency of motor-driven equipment by matching speed to changing load requirements (energy saving).
2. To allow accurate and continuous process control over a wide range of speeds (Better process control).

Motor-driven centrifugal pumps, fans and blowers offer the most dramatic energy-saving opportunities.

...

In addition to two main benefits (energy savings and better process control), Variable Frequency Drives (VFDs) can provide other benefits:

1. VFDs may be used for control of process temperature, pressure or flow, without the use of a separate controller. Suitable sensors and electronics are used to interface the driven equipment with the VFDs.

2. Maintenance costs can be lower, since lower operating speeds result in longer life for bearings & motors.