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hoe to draw bidirectional dc dc converter for dc nano grid in ltspice

Started by chetan June 9, 2018
I need to design nonisolated dc-dc bidirectional converter for dc nano gride
system. i am not sure how to draw in ltspice or in Matlab. please help me out. 

-- 


On Sunday, June 10, 2018 at 9:37:11 AM UTC+10, chetan wrote:
> I need to design nonisolated dc-dc bidirectional converter for dc nano gride > system. i am not sure how to draw in ltspice or in Matlab. please help me out. > > --
Bi-directional DC-to-DC converters are tricky. You could use a Royer inverter to generate an alternating square wave, put it through a transformer to step the voltage up or down, and use active rectification to turn the AC emerging from the other side of the transformer back into a different DC voltage. Square waves are a bit brutal. Baxandall inverters generate sine waves (albeit with some harmonic content) which can be easier to handle. http://sophia-elektronica.com/0344_001_Baxandal.pdf Baxandall wrote that in 1959, before MOSFETs had been invented. His circuit tends to work better with MOSFET switches, though driving them can be tricky. The inverter to active rectifier route is potentially reversible, and you can represent and simulate that kind of circuit in LTSpice. Matlab isn't designed for that. The way the question is posed suggests that you haven't got a clue what you are talking about. A longer post, telling us what you want to do and why you want to do it, might get more helpful responses. It might also generate hurtful comments about dumb newbies, but there's no gain without some risk of pain. -- Bill Sloman, Sydney
On Sunday, 10 June 2018 00:37:11 UTC+1, chetan  wrote:
> I need to design nonisolated dc-dc bidirectional converter for dc nano gride > system. i am not sure how to draw in ltspice or in Matlab. please help me out.
Start by defining your requirements, then pick your topology. NT
On 2018-06-09, chetan <f6ceedb9c75b52f7fcc0a55cf0cfbf5d_1105@example.com> wrote:
> I need to design nonisolated dc-dc bidirectional converter for dc nano gride > system. i am not sure how to draw in ltspice or in Matlab. please help me out.
Do you mean that energy can flow in both directions? -- &#1578;
Jasen Betts wrote...
> > On 2018-06-09, chetan wrote: >> >> I need to design nonisolated dc-dc bidirectional converter >> for dc nano gride system. i am not sure how to draw in >> ltspice or in Matlab. please help me out. > > Do you mean that energy can flow in both directions?
Fully synchronous buck or boost converters are bi-directional. Current flows to maintain an in/out voltage ratio, set by the duty cycle of the two switch system. (Synchronous converters use switches instead of diodes.) For example, you can equalize the charge state between a 12V and a 42V battery. I like to call them bus converters. The nano-grid concept appears to be house-wide systems replacing the traditional AC power lines. They assume energy sources in your home. I have 8.5kW solar- panel on my roof to feed my house-hold use, with the extra going to the grid. But it works using conventional AC lines. -- Thanks, - Win
On 10/06/2018 00:37, chetan wrote:
> I need to design nonisolated dc-dc bidirectional converter for dc nano > gride > system. i am not sure how to draw in ltspice or in Matlab. please help > me out.
It would help to know the voltages and currents involved on each side. Is it to step up, step down, invert polarity etc. piglet
Winfield Hill wrote:
> Jasen Betts wrote... >> >> On 2018-06-09, chetan wrote: >>> >>> I need to design nonisolated dc-dc bidirectional converter >>> for dc nano gride system. i am not sure how to draw in >>> ltspice or in Matlab. please help me out. >> >> Do you mean that energy can flow in both directions? > > Fully synchronous buck or boost converters are bi-directional. > Current flows to maintain an in/out voltage ratio, set by the > duty cycle of the two switch system. (Synchronous converters > use switches instead of diodes.) For example, you can equalize > the charge state between a 12V and a 42V battery. I like to > call them bus converters. The nano-grid concept appears to be > house-wide systems replacing the traditional AC power lines. > They assume energy sources in your home. I have 8.5kW solar- > panel on my roof to feed my house-hold use, with the extra > going to the grid. But it works using conventional AC lines.
What page is that on? :)
On Monday, June 11, 2018 at 12:44:06 PM UTC+10, Tom Del Rosso wrote:
> Winfield Hill wrote: > > Jasen Betts wrote... > >> > >> On 2018-06-09, chetan wrote: > >>> > >>> I need to design nonisolated dc-dc bidirectional converter > >>> for dc nano gride system. i am not sure how to draw in > >>> ltspice or in Matlab. please help me out. > >> > >> Do you mean that energy can flow in both directions? > > > > Fully synchronous buck or boost converters are bi-directional. > > Current flows to maintain an in/out voltage ratio, set by the > > duty cycle of the two switch system. (Synchronous converters > > use switches instead of diodes.) For example, you can equalize > > the charge state between a 12V and a 42V battery. I like to > > call them bus converters. The nano-grid concept appears to be > > house-wide systems replacing the traditional AC power lines. > > They assume energy sources in your home. I have 8.5kW solar- > > panel on my roof to feed my house-hold use, with the extra > > going to the grid. But it works using conventional AC lines. > > What page is that on? :)
It's in the even-more extended edition, which hasn't been published yet (and probably never will be) and - for the moment - only exists in the minds of people who know something about electronic design (which excludes Tom Del Rosso). -- Bill Sloman, Sydney
bill.sloman@ieee.org wrote:
> On Monday, June 11, 2018 at 12:44:06 PM UTC+10, Tom Del Rosso wrote: >> Winfield Hill wrote: >>> Jasen Betts wrote... >>>> >>>> On 2018-06-09, chetan wrote: >>>>> >>>>> I need to design nonisolated dc-dc bidirectional converter >>>>> for dc nano gride system. i am not sure how to draw in >>>>> ltspice or in Matlab. please help me out. >>>> >>>> Do you mean that energy can flow in both directions? >>> >>> Fully synchronous buck or boost converters are bi-directional. >>> Current flows to maintain an in/out voltage ratio, set by the >>> duty cycle of the two switch system. (Synchronous converters >>> use switches instead of diodes.) For example, you can equalize >>> the charge state between a 12V and a 42V battery. I like to >>> call them bus converters. The nano-grid concept appears to be >>> house-wide systems replacing the traditional AC power lines. >>> They assume energy sources in your home. I have 8.5kW solar- >>> panel on my roof to feed my house-hold use, with the extra >>> going to the grid. But it works using conventional AC lines. >> >> What page is that on? :) > > It's in the even-more extended edition, which hasn't been published > yet (and probably never will be) and - for the moment - only exists > in the minds of people who know something about electronic design > (which excludes Tom Del Rosso).
You forgot the smiley. There are also people who have been regular posters and have passed away and are missed (which will exclude you when you croak because you won't be missed at all).
On Monday, 11 June 2018 07:42:03 UTC+1, Tom Del Rosso  wrote:
> bill.sloman@ieee.org wrote: > > On Monday, June 11, 2018 at 12:44:06 PM UTC+10, Tom Del Rosso wrote: > >> Winfield Hill wrote: > >>> Jasen Betts wrote... > >>>> > >>>> On 2018-06-09, chetan wrote: > >>>>> > >>>>> I need to design nonisolated dc-dc bidirectional converter > >>>>> for dc nano gride system. i am not sure how to draw in > >>>>> ltspice or in Matlab. please help me out. > >>>> > >>>> Do you mean that energy can flow in both directions? > >>> > >>> Fully synchronous buck or boost converters are bi-directional. > >>> Current flows to maintain an in/out voltage ratio, set by the > >>> duty cycle of the two switch system. (Synchronous converters > >>> use switches instead of diodes.) For example, you can equalize > >>> the charge state between a 12V and a 42V battery. I like to > >>> call them bus converters. The nano-grid concept appears to be > >>> house-wide systems replacing the traditional AC power lines. > >>> They assume energy sources in your home. I have 8.5kW solar- > >>> panel on my roof to feed my house-hold use, with the extra > >>> going to the grid. But it works using conventional AC lines. > >> > >> What page is that on? :) > > > > It's in the even-more extended edition, which hasn't been published > > yet (and probably never will be) and - for the moment - only exists > > in the minds of people who know something about electronic design > > (which excludes Tom Del Rosso). > > You forgot the smiley. There are also people who have been regular > posters and have passed away and are missed (which will exclude you when > you croak because you won't be missed at all).
kf him. The S/N ratio is about 1000:1. NT