HACHEURS : Cours et Exercices corrigés
Les hacheurs sont les convertisseurs statiques qui permettent le transfert de l’énergie électrique d’une source continue vers une autre source continue. (Ils sont l’équivalents des transformateurs en alternatif). Lorsque l’entrée et la sortie sont de natures dynamiques différentes, on peut les relier directement (on parle alors de hacheur à liaison directe). Lorsqu’elles sont de même nature dynamique, il faut faire appel à un élément de stockage momentané (on parle dans ce cas de hacheur à accumulation). Enfin dans le cas où l’isolation galvanique de la sortie avec l’entrée est une nécessité, on réalise des hacheurs dits « isolés ».
Suivant le degré de réversibilité que l’on désire, la structure du montage diffère.
Enfin, suivant la puissance nominale du système, la technologie des composants ne sera pas la même.
I- Familles de hacheurs
On distingue deux familles de convertisseurs continu / continu.
– Les hacheurs à liaison continue (continuité électrique entre entrée et sortie), Charge rapide et contrôlée de batteries d’accumulateurs, et typiquement entraînement de moteurs à courant continu à vitesse variable,
– Les alimentations à découpage avec isolation galvanique.
Les alimentations à découpage se sont fortement développées pour remplacer les, alimentations linéaires de poids élevé et faible rendement. Elles sont utilisées désormais dans tous les appareils électroniques « grand public »
II- Différents types de hacheur
On distingue :
- Le hacheur série
- Le hacheur parallèle
- Les hacheurs 2 et 4 quadrants
- Les alimentations à découpage.
III- Quelques Applications
Le hacheur est principalement utilisé pour :
- La variation de vitesse d’un moteur à courant continu
- Le freinage par récupération
- Alimentation d’appareil électronique grand public (PC, …)
VI- Hacheur série – Abaisseur de tension
Le schéma de principe du hacheur série est donné à la figure ci-dessous. On considère l’interrupteur I et la diode D parfaits. La charge est par exemple un moteur à courant continu.
Le fonctionnement du convertisseur se déduit de l’analyse du comportement de l’interrupteur I.
- à t=0, I est enclenché (passant) pendant un temps αT , alors : ud (t) = U
- entre αT et T (αT< t < T ), I est ouvert.
On a alors : i=0 et le courant id circule à travers la diode D (diode de « roue libre »).
Donc : ud (t) = 0 tant que la diode D conduit, soit tant que le courant id (t) est non nul.
- Lorsque id (t) s’annule, la diode D se bloque et : ud (t) = Ec
On distingue donc deux types de fonctionnement selon que le courant id (t) est interrompu ou non.
Fonctionnement à courant ininterrompu
La valeur moyenne de ud (t) vaut :
Remarque : la FEM Ec de la charge et la valeur moyenne Id0 du courant id (t) sont liés par :
- Si la charge est une batterie ( Ec est imposé par la charge), cette relation définit Id0
- Si la charge est un moteur à courant continu, cette relation fixe Ec (et donc la vitesse du moteur car Ec= KΩ (Ω en rad/s)), sachant que Id0 dépend du moment du couple du moteur M (M= KI si l’on néglige les pertes mécaniques et les pertes par hystéréris et courants de Foucault).
Fonctionnement à courant dans la charge interrompu
Lorsque l’interrupteur s’ouvre, à t = αT, le courant id(t) décroît. Si la constante de temps τ=Ic/Rc est suffisamment faible devant T, ce courant s’annule avant que l’interrupteur ne redevienne passant à t=T. En considérant que le courant id (t) est nul entre les instants βT et T, la valeur moyenne de ud (t) vaut alors :
Conclusion sur le hacheur série
Dans les deux types de fonctionnement, on voit que la valeur moyenne Ud0 de la tension disponible aux bornes de la charge est fonction du rapport cyclique α . On réglera la valeur de Ud0 en modifiant le rapport cyclique α :
1. soit en modifiant la durée de conduction de l’interrupteur I sans modifier la période T de commande (Modulation de Largeur d’Impulsion, MLI).
2. soit en modifiant la fréquence de commande ( f=1/T) sans modifier la durée de conduction de l’interrupteur.
La solution 1 est de loin la plus utilisée en pratique car elle permet un filtrage aisé de la tension ud(t) par un filtre passe-bas comme le décrit la figure ci-dessous. Ce filtre passe-bas permet d’éliminer les harmoniques élevés de ud(t).
V- Hacheur parallèle – Elévateur de tension
Le hacheur parallèle est aussi appelé hacheur survolteur. Ce montage permet de fournir une tension moyenne Ud0 à partir d’une source de tension continue U < Ud0 . Le montage étudié est donné à la figure ci-dessous :
Les applications principales du hacheur parallèle sont les alimentations de puissance régulées et le freinage par récupération des moteurs à courant continu. On distingue 2 phases de fonctionnement :
- Lorsque l’interrupteur I est fermé, la diode est polarisée en inverse (vD = -ud ); la charge est donc isolée de la source. La source fournit de l’énergie à l’inductance l.
- Lorsque l’interrupteur I est ouvert, l’étage de sortie (C+ charge) reçoit de l’énergie de la source et de l’inductance l.
Pour l’analyse en régime permanent présentée ici, le condensateur de filtrage C a une valeur de capacité suffisamment élevée pour que l’on puisse considérer la tension disponible en sortie constante : ud (t) = Ud0
Enfin on distingue deux modes de fonctionnement selon que le courant dans l’inductance l (il (t) ) est interrompu ou non.
VI- Application des hacheurs série et parallèle :
Alimentation et freinage d’un moteur à courant continu à l’aide d’un hacheur réversible
Le montage étudié est décrit sur la figure ci-dessous :
Le hacheur série est constitué de la diode D1 et de l’interrupteur I1. Le hacheur parallèle est constitué de la diode D2 et de l’interrupteur I2.
La machine fonctionne en moteur lorsqu’elle est alimentée par le hacheur série (D2 reste toujours bloquée car U > ud et I2 est maintenu ouvert).
La machine fonctionne en génératrice (phase de freinage) et alimente la source U (batterie par exemple) lorsque le hacheur parallèle est utilisé (D1 est toujours bloquée car lorsque I2 est fermé VD1 = 0 et lorsque I2 est ouvert D2 est passante et VD1 = -U ; I1 est maintenu ouvert).
Pour plus de détails télécharger les documents ci-dessous:
Liens de téléchargement des cours sur HACHEURS
Cours sur les HACHEURS N°1
Cours sur les HACHEURS N°2
Cours sur les HACHEURS N°3
Cours sur les HACHEURS N°4
Cours sur les HACHEURS N°5
Cours sur les HACHEURS N°6
Cours sur les HACHEURS N°7
Cours sur les HACHEURS N°8
Liens de téléchargement des exercices corrigés sur HACHEURS
Exercices corrigés sur les HACHEURS N°1
Exercices corrigés sur les HACHEURS N°2
Exercices corrigés sur les HACHEURS N°3
Exercices corrigés sur les HACHEURS N°5
Thanks very interesting blog!
This post is genuinely a good one it helps new
web viewers, who are wishing for blogging.
There’s definately a great deal to know about this
topic. I like all the points you have made.
I just like the helpful information you supply in your articles.
I will bookmark your blog and check once more here regularly.
I am rather certain I’ll learn a lot of new stuff
right here! Best of luck for the following!
Wonderful goods from you, man. I’ve have in mind your stuff previous to and you are simply
extremely magnificent. I actually like what you have obtained right here, really like
what you’re saying and the way in which you assert it.
You are making it entertaining and you continue to take care of to keep it wise.
I can not wait to learn much more from you. This is really
a great website.
Hey! This is my 1st comment here so I just wanted to give a
quick shout out and say I really enjoy reading
your articles. Can you suggest any other blogs/websites/forums that cover the
same topics? Thank you so much!
What a data of un-ambiguity and preserveness of valuable experience on the topic of unpredicted feelings.
What’s up all, here every person is sharing these kinds of know-how, thus
it’s good to read this blog, and I used to pay a
visit this web site every day.
I couldn’t refrain from commenting. Very
well written!
My brother recommended I may like this web site. He was
once totally right. This submit truly made my day.
You can not imagine just how much time I had spent for this information! Thanks!
I think this is among the most vital info for me. And i’m glad reading your article.
But wanna remark on few general things, The site style is wonderful, the articles is really great
: D. Good job, cheers
Hi there, yeah this paragraph is actually pleasant and I have learned lot of things from it regarding
blogging. thanks.
What’s up mates, its enormous post regarding cultureand fully
defined, keep it up all the time.
Thanks for sharing your info. I really appreciate your efforts and I will be
waiting for your next post thank you once again.
Its such as you read my mind! You seem to understand a lot about this, like you
wrote the e-book in it or something. I think that you just could do with a few
p.c. to power the message home a little bit, but instead of that, that is magnificent
blog. A fantastic read. I’ll certainly be back.
You really make it seem so easy with your presentation but I find this
topic to be actually something which I think I would never understand.
It seems too complex and extremely broad for me.
I am looking forward for your next post, I’ll try to get the hang of it!
Hi terrific website! Does running a blog such as this require a lot of work?
I have no expertise in coding however I had been hoping to start my own blog soon. Anyways, should you have any suggestions or techniques for new
blog owners please share. I know this is off subject but I simply wanted to ask.
Appreciate it!
magnificent post, very informative. I ponder why the opposite
specialists of this sector don’t realize this. You must proceed your writing.
I’m confident, you have a huge readers’ base already!
Hi there it’s me, I am also visiting this site
on a regular basis, this website is actually pleasant and the people
are truly sharing fastidious thoughts.
I enjoy what you guys are usually up too. Such
clever work and reporting! Keep up the very good works guys I’ve added you guys to blogroll.
You actually make it seem so easy together with your presentation but I
find this matter to be really one thing which I believe I’d
never understand. It kind of feels too complicated and extremely large for me.
I’m looking forward for your next publish, I will try to get the grasp
of it!
I could not refrain from commenting. Perfectly written!
Every weekend i used to pay a visit this web page, as i wish for enjoyment, for the reason that this this web page conations in fact pleasant funny
stuff too.
Hmm it appears like your site ate my first comment (it was super
long) so I guess I’ll just sum it up what I wrote and say, I’m
thoroughly enjoying your blog. I as well am an aspiring blog writer but I’m still new to everything.
Do you have any recommendations for inexperienced blog writers?
I’d genuinely appreciate it.
Excellent blog! Do you have any recommendations for aspiring writers?
I’m hoping to start my own blog soon but I’m a little lost on everything.
Would you recommend starting with a free platform like
Wordpress or go for a paid option? There are so many
options out there that I’m totally overwhelmed .. Any tips?
Cheers!
Hey There. I discovered your weblog using msn. This is a
really smartly written article. I will be sure to bookmark it
and return to learn more of your useful info. Thanks for the post.
I will definitely comeback.
Hello all, here every person is sharing such knowledge, therefore it’s nice
to read this website, and I used to visit this web site daily.
Nice blog! Is your theme custom made or did you download it from somewhere?
A theme like yours with a few simple adjustements would really make my blog shine.
Please let me know where you got your design. Thank you
I am sure this post has touched all the internet visitors,
its really really fastidious piece of writing on building up new web site.
Yes! Finally something about gum disease.
Pretty! This was a really wonderful post. Many thanks for providing this information.
Right here is the perfect webpage for everyone who would like to
understand this topic. You realize a whole lot its almost tough to argue with
you (not that I really will need to…HaHa). You definitely
put a new spin on a topic which has been written about for ages.
Wonderful stuff, just excellent!
Appreciate this post. Let me try it out.
Having read this I thought it was extremely informative.
I appreciate you finding the time and energy to put this information together.
I once again find myself personally spending
way too much time both reading and posting comments.
But so what, it was still worth it!
Hmm is anyone else encountering problems with the pictures on this blog loading?
I’m trying to determine if its a problem on my end or if it’s the blog.
Any feedback would be greatly appreciated.
Hi, i believe that i saw you visited my weblog thus i got here to go back
the favor?.I am attempting to in finding things to enhance my website!I suppose its
adequate to use a few of your concepts!!
If some one needs to be updated with most recent technologies
therefore he must be pay a visit this website and be up to date everyday.
I enjoy what you guys are usually up too. This kind of clever
work and exposure! Keep up the superb works guys I’ve added
you guys to my personal blogroll.
Sweet blog! I found it while surfing around on Yahoo News.
Do you have any tips on how to get listed in Yahoo News?
I’ve been trying for a while but I never seem to
get there! Thanks
Good day! Do you know if they make any plugins to protect against hackers?
I’m kinda paranoid about losing everything I’ve
worked hard on. Any suggestions?
I was wondering if you ever thought of changing the layout of your website?
Its very well written; I love what youve got to say. But maybe you could
a little more in the way of content so people could connect with it better.
Youve got an awful lot of text for only having one or two pictures.
Maybe you could space it out better?
Hi there outstanding blog! Does running a blog similar
to this require a massive amount work? I’ve absolutely no expertise in computer programming but I had been hoping to
start my own blog in the near future. Anyway, should you have any suggestions or techniques for new blog owners
please share. I understand this is off topic but I
simply had to ask. Thanks a lot!
I am actually glad to glance at this weblog posts which contains lots of helpful facts, thanks for providing these information.
I am actually happy to glance at this weblog posts which
contains plenty of useful information, thanks for providing such data.
I think the admin of this web page is really working hard in favor of his web page, since here every stuff is quality based stuff.
I simply could not leave your website before suggesting that I extremely enjoyed the usual info an individual provide
in your visitors? Is going to be back steadily to check out new posts
Asking questions are actually pleasant thing if you are not
understanding something totally, except this paragraph gives good understanding even.
I really like your blog.. very nice colors & theme. Did
you design this website yourself or did you hire someone to do it
for you? Plz reply as I’m looking to create my own blog and would like to find out where u got
this from. thanks a lot
Heya i am for the first time here. I came across this board and I to find It truly helpful &
it helped me out much. I am hoping to present one thing back and
help others such as you helped me.
I really like it when people get together and share thoughts.
Great website, keep it up!
Hi just wanted to give you a quick heads up
and let you know a few of the pictures aren’t loading properly.
I’m not sure why but I think its a linking issue.
I’ve tried it in two different web browsers and both show the
same outcome.
Good post however I was wondering if you could write a litte more on this
subject? I’d be very thankful if you could elaborate a little bit
further. Many thanks!
There is certainly a great deal to find out about this topic.
I really like all the points you made.
You’ve made some good points there. I looked on the net to learn more about the issue and found most individuals will go
along with your views on this web site.
Simply wish to say your article is as astonishing.
The clarity for your post is simply spectacular
and that i could assume you’re an expert in this subject.
Fine with your permission allow me to seize your feed
to keep updated with approaching post. Thanks a million and please continue the gratifying work.
What i don’t realize is in reality how you’re no longer actually much more smartly-liked than you may be
now. You’re so intelligent. You recognize thus considerably with regards to this subject, produced me personally believe it from
so many numerous angles. Its like men and women are not fascinated except it is one thing to accomplish with Woman gaga!
Your own stuffs great. Always care for it
up!
I was curious if you ever considered changing the structure of your site?
Its very well written; I love what youve got to say. But maybe you could a little
more in the way of content so people could connect with it better.
Youve got an awful lot of text for only having one or 2 pictures.
Maybe you could space it out better?
I needed to thank you for this very good read!! I absolutely loved
every bit of it. I’ve got you book marked to check out new things you post…
We are a group of volunteers and opening a new scheme in our community.
Your website offered us with valuable information to work on. You’ve done a formidable job and our
whole community will be grateful to you.
Oh my goodness! Incredible article dude! Many
thanks, However I am having problems with your RSS.
I don’t understand why I am unable to join it. Is there anybody getting similar RSS problems?
Anybody who knows the answer will you kindly respond?
Thanks!!
Highly energetic article, I loved that bit.
Will there be a part 2?
This paragraph offers clear idea in favor of the new users of blogging,
that in fact how to do running a blog.
Hello there, I discovered your blog by means of Google while searching for a comparable matter, your
website got here up, it looks good. I have
bookmarked it in my google bookmarks.
Hi there, simply became aware of your blog through Google, and located that it
is really informative. I am gonna watch out for brussels.
I’ll appreciate when you proceed this in future. Numerous
other people might be benefited from your writing.
Cheers!
Pretty great post. I simply stumbled upon your blog and
wanted to mention that I’ve really enjoyed browsing your weblog posts.
After all I’ll be subscribing to your feed and I hope you write again very soon!
Your style is very unique compared to other people I have read stuff from.
Thank you for posting when you’ve got the opportunity, Guess I will just book mark this web site.
Because the admin of this website is working, no uncertainty very
quickly it will be famous, due to its feature contents.
Howdy I am so excited I found your blog, I really found you by
mistake, while I was browsing on Bing for something else,
Regardless I am here now and would just like to say thanks a lot for a marvelous post and a all
round enjoyable blog (I also love the theme/design), I don’t have time to read it all at the
moment but I have book-marked it and also added in your RSS feeds, so
when I have time I will be back to read much more, Please do keep up the fantastic work.
It’s a pity you don’t have a donate button! I’d definitely donate to this brilliant
blog! I guess for now i’ll settle for book-marking and adding your RSS feed to my Google account.
I look forward to new updates and will talk about this blog with my Facebook group.
Chat soon!
My family members every time say that I am wasting my time here
at web, but I know I am getting knowledge all the time by
reading such pleasant posts.
Thanks for your marvelous posting! I truly enjoyed reading it,
you’re a great author. I will be sure to bookmark your blog
and will come back down the road. I want to encourage
you to ultimately continue your great posts, have a nice morning!
I have read so many articles about the blogger lovers however this
piece of writing is in fact a fastidious article, keep it up.