modelling bidirectional dc-dc converters for hybrid vehicles

[Nickys13]

dc-dc converters for hybrid vehicle

Hello everyone, I would be very grateful if I could have some advice regarding my project.

My task is to connect the HV battery of a plug in series hybrid vehicle to the motor using the appropriate converter. I will need to boost the voltage from approximately 280V to 700V. This connection needs to be bidirectional because the motor is operating as a generator during regenerative braking and needs to charge the battery back. However the generator's output is Ac so I will need an Ac/dc inverter as well.

the last part is to connect another generator driven by the Internal Combustion Engine to charge the battery but also with the ability to drive the motor directly.. This will need another ac/dc inverter.

For the first part I was thinking of an isolated bidirectional dc-dc converter followed by a buck boost. I would like to ask if you know any literature that give a similar solution to this problem, preferably sources that provide all the relevant equations.
Also I would be pleased if I could find some relevant simulations of the above converters in Simulink.

I have attached the vehicle's schematic which shows all the relevant connections. I can also provide the files of the motor and the generators upon request, if you need it to offer any advice.

Thanks a lot in advance!

 

[FvM]

bidirectional ac-dc converter

I think, there are contributions related to hybrid drive concepts in automotive electronics professional journals. Obviously, many major automotive companies are already working with prototype designs of high voltage hybrid drive.

Generally, you didn't clarify, if you are doing research at the system concept level or are also involved in inverter circuit design. Simulink simulation e.g. may be helpful in evaluating the overall system behaviour but can't give answers to circuit design questions.

As you mentioned isolated DC/DC. I think, I won't be used in automotive unless explicitely required by safety concepts or resulting in efficiency or weight/volume advantages, which probably isn't the case, either.

 

[Nickys13]

dc converter hybrid vehicles

I am a 4th Year student, unfortunately I am not much of an expert. I will have to come up with a few ideas - solutions to the problem and try to simulate them in simulink by connecting the already designed motor and generator.

The motor is a Permanent Magnet Synchronous Motor which is a Brushless DC motor that uses a synchronous mode of operation. I am not required to know about it in detail, it just needs to be supplied by constant voltage of 700V as previously mentioned. This is a bit higher than usual but not surprising- common value is around 600V.

Someone mentioned to me that it is too much of a step -up in voltage. How about making this in 2 steps if this poses a problem?

As for the isolated converter, it is not a requirement I had just come accross a few papers suggesting this. Do you have any simulations in simulink of bidirectional converters, buck-boost or ac/dc inverters?



Thanks