What are the best inverter topologies for low power induction motors?

[saboor42390]

Hi folks, I'm new to both the forums and the concept of inverters.

For my project, I've been told to look up various inverter topologies.

I've read inverters in a textbook, course notes, over the web, with PLECS, and I'm still confused.

Maybe, I just need a good place to start. I understand basics of circuits.

I've been trying to simulate inverters using PLECS to no avail. Although, that could just be my lack of experience with the software.

I'm supposed to simulate a way to convert DC voltage into three-phase AC voltage. Our group leader has designated a pulse-width modulated (PWM) hex-bridge inverter to be implemented.

However, we do not necessarily have to follow the above design. We're pretty free in deciding what works best for our low power induction motor. I just need to find a good way to create a sinusoidal voltage after a DC/DC converter steps up the voltage.

So, for the more experienced of you, any topologies that would work for this situation?

I'd appreciate schematics, circuit diagrams, links, etc.

I'm really lost here and don't know where to turn. Thank you.

 

[acdrive]

Hi folks, I'm new to both the forums and the concept of inverters.

For my project, I've been told to look up various inverter topologies.

I've read inverters in a textbook, course notes, over the web, with PLECS, and I'm still confused.

Maybe, I just need a good place to start. I understand basics of circuits.

I've been trying to simulate inverters using PLECS to no avail. Although, that could just be my lack of experience with the software.

I'm supposed to simulate a way to convert DC voltage into three-phase AC voltage. Our group leader has designated a pulse-width modulated (PWM) hex-bridge inverter to be implemented.

However, we do not necessarily have to follow the above design. We're pretty free in deciding what works best for our low power induction motor. I just need to find a good way to create a sinusoidal voltage after a DC/DC converter steps up the voltage.

So, for the more experienced of you, any topologies that would work for this situation?

I'd appreciate schematics, circuit diagrams, links, etc.

I'm really lost here and don't know where to turn. Thank you.

inverter is an efficient and reliable devices that come in a variety of sizes and power ranges for ac/dc motors, maybe you just need to start with how the inverter be used for?

 

[FOIWATER]

I don't want to under-mind you, but are you familiar with electronic switches (IGBT) used for dc to ac inversion?

They are transistors with 4 layers of alternating P & N junction material. As a switch, a gate pulse allows the IGBT to turn on and off it can do so thousands of times per second.

So, you can form sine waves from a DC pulse, by gating the igbt, turning it off. Letting it come on a little longer, turning it off, letting it come on a little longer turn it off etc.

As you gate it, the signal tries to rise up to the DC value, but you switch it. Then let it come on a little longer, it goes a little higher, etc

It makes it look a bit like using integration by rectangles ... haha

But you can form sine waves like this, by gating the IGBT's in the proper sequence.

That's how we do inversion at work

 

[jim hardy]

For my project, I've been told to look up various inverter topologies.

I've read inverters in a textbook, course notes, over the web, with PLECS, and I'm still confused.

the best textbook i know of is the GE SCR manual. Its inverter chapter is a pactical "how it works" . It covers several topologies. But it is old school, for the new pwm synthesized ones you 'll need a newer book.
But to get you started this can't be beat. I prefer fourth and fifth editions , myself, they're a little less math intensive.

https://www.amazon.com/dp/0137967632/?tag=pfamazon01-20

 

[alphysicist]

I would first like to commend you for seeking out various resources and attempting to simulate inverters using PLECS. It shows determination and a strong drive to understand the topic at hand.

To start, it is important to have a clear understanding of what an inverter is and its purpose. Inverters are electronic devices that convert DC voltage into AC voltage. They are commonly used in various applications such as power supplies, motor drives, and renewable energy systems.

In terms of topologies, there are several options for low power induction motors. Some commonly used topologies include the half-bridge, full-bridge, and three-phase bridge inverters. Each has its own advantages and limitations, so it is important to carefully consider the specific requirements and characteristics of your low power induction motor before selecting a topology.

In your case, your group leader has suggested a PWM hex-bridge inverter. This topology is commonly used for its ability to provide a sinusoidal output voltage, which is important for the operation of AC motors. However, it is not the only option and you are free to explore other topologies that may better suit your specific needs.

To create a sinusoidal voltage after a DC/DC converter, you will need to implement a control strategy that regulates the output voltage. This can be achieved through various techniques such as pulse-width modulation (PWM) or hysteresis control. It is important to carefully design and tune the control strategy to ensure stable and efficient operation of the inverter.

For more detailed guidance, I would suggest consulting with experienced engineers or professors in the field of power electronics. They can provide valuable insights and assistance in selecting the most suitable topology and designing a proper control strategy for your specific application.

In terms of resources, there are many online tutorials, books, and research papers available on inverter topologies and control strategies. I would recommend starting with a basic understanding of power electronics and then delving into more specific topics related to inverters and motor control.

I hope this response has provided some guidance and direction for your project. Remember to keep an open mind and continue seeking out resources and assistance when needed. Best of luck in your research and experimentation.