Should I choose a 10KV high-voltage inverter or a 690V inverter?

The later maintenance costs for Option 1 are a problem, but its reliability is quite high. Option 2 has relatively lower maintenance costs in the long term, but the mechanical properties and process parameters after replacing the motor may not meet the requirements.

Replacing the high-voltage motor with a 690V motor of 800KW capacity will certainly result in an increase in current flow, so it is necessary to increase the cross-sectional area of the wiring; this cost should be taken into account. Since 690V frequency converters are reliable, it would be worth trying out 10KV frequency converters as well. If one is not willing to try new things, how can progress be achieved in society?

1. Carefully calculate the costs required for the two options (including equipment, materials, labor, etc.). If the cost of the high-voltage inverter solution is not more than 1.2 times that of the low-voltage solution, it is recommended to use the high-voltage solution.

Those who suggested using high-voltage frequency converters above are all people who have no experience working on high-voltage frequency converter projects! For installations of 1200 KW or less, low-voltage frequency converters should be used; this is a conclusion I have reached after working on high-voltage frequency converter projects for over 10 years. The decision is based on factors such as the initial investment, operating and maintenance costs, and the reliability of the equipment. The mechanical properties that people are concerned about have no direct connection with the rated voltage of the motor. As for converting high-voltage motors into low-voltage motors of the same capacity, this can be done at large motor factories or electrical repair shops across the country. Moreover, there are many engineering companies that specialize in such conversions and also offer services for recycling high-voltage motors. For 10KV high-voltage frequency converters, from a cost-performance perspective, domestic options are the only choice available at present; their reliability goes without saying!

Since our factory demands high reliability from its equipment, with only a few days of downtime allowed per year, we actually choose the 690V version. It seems that everyone really lacks confidence in the reliability of high-voltage frequency converters

6# Just wandering around the world – reliability isn’t an issue; the key is the price! !

High-voltage frequency converters are also very stable. It’s not necessarily the case that low-voltage systems are more reliable than high-voltage ones. In terms of the overall cost, the low-voltage version should be more expensive; how large does that cable need to be? In favor of using high pressure.

I forgot one thing: high-pressure systems also have bypass circuits, so in case something goes wrong, you won’t be in trouble and can handle it. But if your motor breaks down, then everyone is in the same situation.

Of course, using a high-voltage frequency converter is better; it is just as safe and reliable. If the frequency converter fails, it can switch to bypass mode, so operation isn’t disrupted. Those in the tech field shouldn’t place too much emphasis on price

Your factory’s 10KV 800KW motors are considered for having their frequency converters changed. There are 2 options available for the frequency converter: 1. Use a high-voltage frequency converter of 10 KV directly; no modification is required for the motor ； The concern is that high-voltage frequency conversion has not been used before, and there are worries about the operational reliability of such equipment ； 2. Use a 690V frequency converter, and replace the motor with a 690V motor; the factory already has fans of the same type (part of the imported equipment), which use this method for speed control ； From an economic perspective: Of course, the first option should be chosen, as the second option requires the addition of motors and other related auxiliary equipment needed to work with those motors. A frequency converter is also necessary, and the power supply cabinet must be replaced. If there is no 690V power supply circuit, a transformer must be added as well, along with high-voltage cables, which are very expensive ； If the first option is chosen, all that’s needed is to add an inverter! In terms of reliability: for 10KV high-voltage frequency converters, there will be no problems if foreign products (such as Robinkong) are used, provided it is determined whether they are suitable for the given altitude I haven’t used any domestic ones, so I can’t be sure about their reliability. Technically speaking, the technical approaches used in both are basically the same. Therefore, it is recommended to choose the first option!