# Connect 120 volt circuits to get 240 volts

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Guest

Sat Jan 05, 2019 12:45 pm

On Sat, 05 Jan 2019 00:58:05 +0200, upsidedown_at_downunder.com wrote:

Quote:

https://youtu.be/qy9pltNa0rY

On Fri, 4 Jan 2019 07:48:32 -0800 (PST), edward.ming.lee_at_gmail.com
wrote:

So, if we hang a diode on each of the 480V 3 phase. We get 240V x (1 + .75 + .75) = 576V. Right? I think their design max out at 700V. Parts get more expensive beyond 700V.

If you are using 480 V delta (with no neutral), better use ordinary 6
pulse rectifier with 6 diodes .

Looking at the specifications and not just listening to the video:

Quote:
It appears that the 700 V they were talking about was after the boost
PFC.

The input is 230/400 V at 3 x 32 A, giving about 25 kW. After PFC, the
voltage is 700 - 750 Vdc.

Quote:

There are several ways of implementing a three phase PFC, one method
is to use three independent single phase rectifier+PFC. The problem is
that the DC from each unit are floating around. Mo big deal, if you
still need DC/C conferrers, just use three separate DC/DC converters
and just combine the final DC output. It appears this is what they are
doing with three holes in the PCB for DC/DC converter transformers.

If they indeed used three independent PFC modules, each starts with a
4 diode bridge, so there would be 12 diodes total. Since the AC input
to each single phase PFC module is taken between two mains phases, so
no need for a neutral connection.

This was incorrect speculations since PFC uses only two big
inductances. Thus some other PFC method is used.

The DC/DC converter uses multiphase DC/DC conversion and in this case,
there happens to be three phase shifted high frequency square waves,
which apparently has nothing to do with mains three phases.

Anyway, it is strange that for three phase systems three separate
transformers are used, since a single three phase transformer would
save some iron, since some of the flux is canceled out in the core.

Guest

Sat Jan 05, 2019 6:45 pm

Quote:
The DC/DC converter uses multiphase DC/DC conversion and in this case,
there happens to be three phase shifted high frequency square waves,
which apparently has nothing to do with mains three phases.

Anyway, it is strange that for three phase systems three separate
transformers are used, since a single three phase transformer would
save some iron, since some of the flux is canceled out in the core.

I guess they are combining the booster and isolation in the final DC stage.
I would rather use a 3 phase input isolation transformer at the initial stage.
I only need to drop and regulate the DC from 600V/700V to 400V.
Don't need to isolate the DC stage.

Guest

Sat Jan 05, 2019 7:45 pm

On Sat, 5 Jan 2019 08:53:11 -0800 (PST), edward.ming.lee_at_gmail.com
wrote:

Quote:
The DC/DC converter uses multiphase DC/DC conversion and in this case,
there happens to be three phase shifted high frequency square waves,
which apparently has nothing to do with mains three phases.

Anyway, it is strange that for three phase systems three separate
transformers are used, since a single three phase transformer would
save some iron, since some of the flux is canceled out in the core.

I guess they are combining the booster and isolation in the final DC stage.
I would rather use a 3 phase input isolation transformer at the initial stage.
I only need to drop and regulate the DC from 600V/700V to 400V.
Don't need to isolate the DC stage.

Do you really mean 25 kVA 50/60 Hz isolation transformer ? Do you
realize how big that would be ?

Compare the size to the switching isolation transformers used.

Guest

Sat Jan 05, 2019 7:45 pm

Quote:
Do you really mean 25 kVA 50/60 Hz isolation transformer ? Do you
realize how big that would be ?

Compare the size to the switching isolation transformers used.

Yes, but I don't have to carry it around, or even drive it around.
A few hundred pounds are no problem for a stationary charger.

Guest

Sun Jan 06, 2019 6:45 am

On Mon, 31 Dec 2018 05:13:30 -0800 (PST), Lasse Langwadt Christensen

Quote:
mandag den 31. december 2018 kl. 14.03.06 UTC+1 skrev upsid...@downunder.com:
On Mon, 31 Dec 2018 00:07:18 +0200, upsidedown_at_downunder.com wrote:

The energy needs for various utility vehicles is of course much
larger, but still city buses can run with a high power charging
station at only at one end of the line. The battery is fully charged
in the time the driver visits the restroom or smokes a cigarette.

??? Where did you get this idea?

There is a charging station about 1 km from where I live and I have
frequently used the bus line in the afternoon returning from the round
trip towards the charging station. The bus accelerates quite strongly
at the end o the leg, so a lot of power must still be available.
Admittedly the total route is less than 10 km long, but this the
second or third winter.

These are Solaris Urbino12 Electric buses. The line round trip
distance is 13 km and according to the schedule, there would be at
most 10 min charging time from the pantograph at the city terminal.
.

yeh they are running some in cities here, 55kWh lithium-titanate battery,
300kW pantograf charger at the end of the line. claims 1kWh/km so only a
few minutes charging needed per trip

Making such charging station should be straight forward. Distribution
transformers over here are in the order of 200-300 kVA. Make a
distribution transformer with multiple secondary windings, each of a
few hundred volts. Feed the zigzag windings to a 12 or 18 pulse
rectifier to avoid the need for PFC.

Such 300 kW power requires just 8 A from a 20 kV medium voltage line.
Just make a branch line from the charging station to an existing 20 kV
network.

Such 300 kW station could alternatively fast charge a dozen 25 kW cars
(such as discussed elsewhere in this thread) simultaneously.

Of course such power levels may cause MV line loading problems in
countries using 4 or 7 kV medium voltage lines.

Guest

Sun Jan 06, 2019 6:45 am

On Saturday, January 5, 2019 at 11:58:44 PM UTC-5, upsid...@downunder.com wrote:
Quote:
On Mon, 31 Dec 2018 05:13:30 -0800 (PST), Lasse Langwadt Christensen

mandag den 31. december 2018 kl. 14.03.06 UTC+1 skrev upsid...@downunder.com:
On Mon, 31 Dec 2018 00:07:18 +0200, upsidedown_at_downunder.com wrote:

The energy needs for various utility vehicles is of course much
larger, but still city buses can run with a high power charging
station at only at one end of the line. The battery is fully charged
in the time the driver visits the restroom or smokes a cigarette.

??? Where did you get this idea?

There is a charging station about 1 km from where I live and I have
frequently used the bus line in the afternoon returning from the round
trip towards the charging station. The bus accelerates quite strongly
at the end o the leg, so a lot of power must still be available.
Admittedly the total route is less than 10 km long, but this the
second or third winter.

These are Solaris Urbino12 Electric buses. The line round trip
distance is 13 km and according to the schedule, there would be at
most 10 min charging time from the pantograph at the city terminal.
.

yeh they are running some in cities here, 55kWh lithium-titanate battery,
300kW pantograf charger at the end of the line. claims 1kWh/km so only a
few minutes charging needed per trip

Making such charging station should be straight forward. Distribution
transformers over here are in the order of 200-300 kVA. Make a
distribution transformer with multiple secondary windings, each of a
few hundred volts. Feed the zigzag windings to a 12 or 18 pulse
rectifier to avoid the need for PFC.

Such 300 kW power requires just 8 A from a 20 kV medium voltage line.
Just make a branch line from the charging station to an existing 20 kV
network.

Such 300 kW station could alternatively fast charge a dozen 25 kW cars
(such as discussed elsewhere in this thread) simultaneously.

Too bad no one drives 25 kWh cars. Well, I guess someone does, but not many. The cars being sold in quantity today have mostly 100 kWh batteries.

Quote:
Of course such power levels may cause MV line loading problems in
countries using 4 or 7 kV medium voltage lines.

Not a problem if they are being charged at night under control of the grid to prevent overloading.

Rick C.

- Get 6 months of free supercharging
- Tesla referral code - https://ts.la/richard11209

Guest

Sun Jan 06, 2019 7:45 am

On Sat, 5 Jan 2019 21:15:57 -0800 (PST),
gnuarm.deletethisbit_at_gmail.com wrote:

Quote:
On Saturday, January 5, 2019 at 11:58:44 PM UTC-5, upsid...@downunder.com wrote:
On Mon, 31 Dec 2018 05:13:30 -0800 (PST), Lasse Langwadt Christensen

mandag den 31. december 2018 kl. 14.03.06 UTC+1 skrev upsid...@downunder.com:
On Mon, 31 Dec 2018 00:07:18 +0200, upsidedown_at_downunder.com wrote:

The energy needs for various utility vehicles is of course much
larger, but still city buses can run with a high power charging
station at only at one end of the line. The battery is fully charged
in the time the driver visits the restroom or smokes a cigarette.

??? Where did you get this idea?

There is a charging station about 1 km from where I live and I have
frequently used the bus line in the afternoon returning from the round
trip towards the charging station. The bus accelerates quite strongly
at the end o the leg, so a lot of power must still be available.
Admittedly the total route is less than 10 km long, but this the
second or third winter.

These are Solaris Urbino12 Electric buses. The line round trip
distance is 13 km and according to the schedule, there would be at
most 10 min charging time from the pantograph at the city terminal.
.

yeh they are running some in cities here, 55kWh lithium-titanate battery,
300kW pantograf charger at the end of the line. claims 1kWh/km so only a
few minutes charging needed per trip

Making such charging station should be straight forward. Distribution
transformers over here are in the order of 200-300 kVA. Make a
distribution transformer with multiple secondary windings, each of a
few hundred volts. Feed the zigzag windings to a 12 or 18 pulse
rectifier to avoid the need for PFC.

Such 300 kW power requires just 8 A from a 20 kV medium voltage line.
Just make a branch line from the charging station to an existing 20 kV
network.

Such 300 kW station could alternatively fast charge a dozen 25 kW cars
(such as discussed elsewhere in this thread) simultaneously.

Too bad no one drives 25 kWh cars.

I said 25 kW not 25 kWh.

According to

the acceptance rate for most cars is below 10 kW, a few Teslas nearly
20 kW.

>Well, I guess someone does, but not many. The cars being sold in quantity today have mostly 100 kWh batteries.

According to the table only two Tesla models are 100 kWh.

Are all buying only these two models ?

Quote:

Of course such power levels may cause MV line loading problems in
countries using 4 or 7 kV medium voltage lines.

Not a problem if they are being charged at night under control of the grid to prevent overloading.

Rick C.

- Get 6 months of free supercharging
- Tesla referral code - https://ts.la/richard11209

Guest

Sun Jan 06, 2019 12:45 pm

On Sunday, January 6, 2019 at 1:06:08 AM UTC-5, upsid...@downunder.com wrote:
Quote:
On Sat, 5 Jan 2019 21:15:57 -0800 (PST),
gnuarm.deletethisbit_at_gmail.com wrote:

On Saturday, January 5, 2019 at 11:58:44 PM UTC-5, upsid...@downunder.com wrote:
On Mon, 31 Dec 2018 05:13:30 -0800 (PST), Lasse Langwadt Christensen

mandag den 31. december 2018 kl. 14.03.06 UTC+1 skrev upsid...@downunder.com:
On Mon, 31 Dec 2018 00:07:18 +0200, upsidedown_at_downunder.com wrote:

The energy needs for various utility vehicles is of course much
larger, but still city buses can run with a high power charging
station at only at one end of the line. The battery is fully charged
in the time the driver visits the restroom or smokes a cigarette.

??? Where did you get this idea?

There is a charging station about 1 km from where I live and I have
frequently used the bus line in the afternoon returning from the round
trip towards the charging station. The bus accelerates quite strongly
at the end o the leg, so a lot of power must still be available.
Admittedly the total route is less than 10 km long, but this the
second or third winter.

These are Solaris Urbino12 Electric buses. The line round trip
distance is 13 km and according to the schedule, there would be at
most 10 min charging time from the pantograph at the city terminal.
.

yeh they are running some in cities here, 55kWh lithium-titanate battery,
300kW pantograf charger at the end of the line. claims 1kWh/km so only a
few minutes charging needed per trip

Making such charging station should be straight forward. Distribution
transformers over here are in the order of 200-300 kVA. Make a
distribution transformer with multiple secondary windings, each of a
few hundred volts. Feed the zigzag windings to a 12 or 18 pulse
rectifier to avoid the need for PFC.

Such 300 kW power requires just 8 A from a 20 kV medium voltage line.
Just make a branch line from the charging station to an existing 20 kV
network.

Such 300 kW station could alternatively fast charge a dozen 25 kW cars
(such as discussed elsewhere in this thread) simultaneously.

Too bad no one drives 25 kWh cars.

I said 25 kW not 25 kWh.

According to

the acceptance rate for most cars is below 10 kW, a few Teslas nearly
20 kW.

Huh??? Most Teslas charge at up to 120 kW. It's a bit more complex than that since the max charge rate varies with state of charge, but is way above 20 kW other than in extreme conditions.

I think you are looking at some very old data or confusing DC charging with level 2 charging.

Maybe the document says most cars are charged at 20 kW or below. The fastest home charging on any Tesla is 20 kW. That's a function of what is practical at home with level 2 and not the same as the fast DC charging (level 3).

Tesla fast chargers, Superchargers, will charge a car at up to 120 kW. Other fast chargers typically are around 50 kW. Some new fast chargers will do up to 300 kW, there are only a handful of them in the world at this point and I don't think any cars will charge that fast yet.

At 25 kW it would take around 4-5 hours to fully charge a 100 kWh battery. The last bit goes a lot slower than the rest.

Quote:
Well, I guess someone does, but not many. The cars being sold in quantity today have mostly 100 kWh batteries.

According to the table only two Tesla models are 100 kWh.

Are all buying only these two models ?

Not sure what you are looking at. The models S, X and 3 all have 100 kWh battery options and even then have several performance options with that.

Most Teslas sold today (meaning more than half) have the 100 kWh battery. It was only in Q4 (if I recall correctly) Tesla came out with another battery option in the model 3 which sells 2.5 times as many as the S and X together.

Quote:
Of course such power levels may cause MV line loading problems in
countries using 4 or 7 kV medium voltage lines.

Not a problem if they are being charged at night under control of the grid to prevent overloading.

Rick C.

- Get 6 months of free supercharging
- Tesla referral code - https://ts.la/richard11209

Rick C.

+ Get 6 months of free supercharging
+ Tesla referral code - https://ts.la/richard11209

Guest

Sun Jan 06, 2019 5:45 pm

Quote:
Making such charging station should be straight forward. Distribution
transformers over here are in the order of 200-300 kVA. Make a
distribution transformer with multiple secondary windings, each of a
few hundred volts. Feed the zigzag windings to a 12 or 18 pulse
rectifier to avoid the need for PFC.

That's what I am searching for: 18 pulses phase shifting inductor.
Found one around 19"x17"x15" 230 pounds. But it's not isolated.
An isolation transformer is probably around the same size and weight.
Seems to be possible to combine them in a single unit, with custom
windings.

PFC should be around 95%, and fine tunning with SiC switches to each
of the nine phases. The duty cycle can also regulate the DC output.

So, just one big transformer, 18 diodes, 9 MOSFET and FPGA.

boB
Guest

Sun Jan 06, 2019 11:45 pm

On Sun, 6 Jan 2019 02:52:47 -0800 (PST),
gnuarm.deletethisbit_at_gmail.com wrote:

Quote:
On Sunday, January 6, 2019 at 1:06:08 AM UTC-5, upsid...@downunder.com wrote:
On Sat, 5 Jan 2019 21:15:57 -0800 (PST),
gnuarm.deletethisbit_at_gmail.com wrote:

On Saturday, January 5, 2019 at 11:58:44 PM UTC-5, upsid...@downunder.com wrote:
On Mon, 31 Dec 2018 05:13:30 -0800 (PST), Lasse Langwadt Christensen

mandag den 31. december 2018 kl. 14.03.06 UTC+1 skrev upsid...@downunder.com:
On Mon, 31 Dec 2018 00:07:18 +0200, upsidedown_at_downunder.com wrote:

The energy needs for various utility vehicles is of course much
larger, but still city buses can run with a high power charging
station at only at one end of the line. The battery is fully charged
in the time the driver visits the restroom or smokes a cigarette.

??? Where did you get this idea?

There is a charging station about 1 km from where I live and I have
frequently used the bus line in the afternoon returning from the round
trip towards the charging station. The bus accelerates quite strongly
at the end o the leg, so a lot of power must still be available.
Admittedly the total route is less than 10 km long, but this the
second or third winter.

These are Solaris Urbino12 Electric buses. The line round trip
distance is 13 km and according to the schedule, there would be at
most 10 min charging time from the pantograph at the city terminal.
.

yeh they are running some in cities here, 55kWh lithium-titanate battery,
300kW pantograf charger at the end of the line. claims 1kWh/km so only a
few minutes charging needed per trip

Making such charging station should be straight forward. Distribution
transformers over here are in the order of 200-300 kVA. Make a
distribution transformer with multiple secondary windings, each of a
few hundred volts. Feed the zigzag windings to a 12 or 18 pulse
rectifier to avoid the need for PFC.

Such 300 kW power requires just 8 A from a 20 kV medium voltage line.
Just make a branch line from the charging station to an existing 20 kV
network.

Such 300 kW station could alternatively fast charge a dozen 25 kW cars
(such as discussed elsewhere in this thread) simultaneously.

Too bad no one drives 25 kWh cars.

I said 25 kW not 25 kWh.

According to

the acceptance rate for most cars is below 10 kW, a few Teslas nearly
20 kW.

Huh??? Most Teslas charge at up to 120 kW. It's a bit more complex than that since the max charge rate varies with state of charge, but is way above 20 kW other than in extreme conditions.

120kW at home with 200A service ?

Quote:

I think you are looking at some very old data or confusing DC charging with level 2 charging.

Maybe the document says most cars are charged at 20 kW or below. The fastest home charging on any Tesla is 20 kW. That's a function of what is practical at home with level 2 and not the same as the fast DC charging (level 3).

Tesla fast chargers, Superchargers, will charge a car at up to 120 kW. Other fast chargers typically are around 50 kW. Some new fast chargers will do up to 300 kW, there are only a handful of them in the world at this point and I don't think any cars will charge that fast yet.

At 25 kW it would take around 4-5 hours to fully charge a 100 kWh battery. The last bit goes a lot slower than the rest.

Well, I guess someone does, but not many. The cars being sold in quantity today have mostly 100 kWh batteries.

According to the table only two Tesla models are 100 kWh.

Are all buying only these two models ?

Not sure what you are looking at. The models S, X and 3 all have 100 kWh battery options and even then have several performance options with that.

Most Teslas sold today (meaning more than half) have the 100 kWh battery. It was only in Q4 (if I recall correctly) Tesla came out with another battery option in the model 3 which sells 2.5 times as many as the S and X together.

Of course such power levels may cause MV line loading problems in
countries using 4 or 7 kV medium voltage lines.

Not a problem if they are being charged at night under control of the grid to prevent overloading.

Rick C.

- Get 6 months of free supercharging
- Tesla referral code - https://ts.la/richard11209

Rick C.

+ Get 6 months of free supercharging
+ Tesla referral code - https://ts.la/richard11209

Guest

Wed Jan 09, 2019 11:45 pm

On Sunday, January 6, 2019 at 4:49:31 PM UTC-5, boB wrote:
Quote:
On Sun, 6 Jan 2019 02:52:47 -0800 (PST),
gnuarm.deletethisbit_at_gmail.com wrote:

On Sunday, January 6, 2019 at 1:06:08 AM UTC-5, upsid...@downunder.com wrote:
On Sat, 5 Jan 2019 21:15:57 -0800 (PST),
gnuarm.deletethisbit_at_gmail.com wrote:

On Saturday, January 5, 2019 at 11:58:44 PM UTC-5, upsid...@downunder..com wrote:
On Mon, 31 Dec 2018 05:13:30 -0800 (PST), Lasse Langwadt Christensen

mandag den 31. december 2018 kl. 14.03.06 UTC+1 skrev upsid...@downunder.com:
On Mon, 31 Dec 2018 00:07:18 +0200, upsidedown_at_downunder.com wrote:

The energy needs for various utility vehicles is of course much
larger, but still city buses can run with a high power charging
station at only at one end of the line. The battery is fully charged
in the time the driver visits the restroom or smokes a cigarette.

??? Where did you get this idea?

There is a charging station about 1 km from where I live and I have
frequently used the bus line in the afternoon returning from the round
trip towards the charging station. The bus accelerates quite strongly
at the end o the leg, so a lot of power must still be available..
Admittedly the total route is less than 10 km long, but this the
second or third winter.

These are Solaris Urbino12 Electric buses. The line round trip
distance is 13 km and according to the schedule, there would be at
most 10 min charging time from the pantograph at the city terminal.
.

yeh they are running some in cities here, 55kWh lithium-titanate battery,
300kW pantograf charger at the end of the line. claims 1kWh/km so only a
few minutes charging needed per trip

Making such charging station should be straight forward. Distribution
transformers over here are in the order of 200-300 kVA. Make a
distribution transformer with multiple secondary windings, each of a
few hundred volts. Feed the zigzag windings to a 12 or 18 pulse
rectifier to avoid the need for PFC.

Such 300 kW power requires just 8 A from a 20 kV medium voltage line.
Just make a branch line from the charging station to an existing 20 kV
network.

Such 300 kW station could alternatively fast charge a dozen 25 kW cars
(such as discussed elsewhere in this thread) simultaneously.

Too bad no one drives 25 kWh cars.

I said 25 kW not 25 kWh.

According to

the acceptance rate for most cars is below 10 kW, a few Teslas nearly
20 kW.

Huh??? Most Teslas charge at up to 120 kW. It's a bit more complex than that since the max charge rate varies with state of charge, but is way above 20 kW other than in extreme conditions.

120kW at home with 200A service ?

Such 300 kW station could alternatively fast charge a dozen 25 kW cars
(such as discussed elsewhere in this thread) simultaneously.

Context. "fast charge"

No one considers L2 to be fast charging. I guess you didn't read far enough to see just what I wrote.

Rick C.

-- Get 6 months of free supercharging
-- Tesla referral code - https://ts.la/richard11209

Quote:
I think you are looking at some very old data or confusing DC charging with level 2 charging.

Maybe the document says most cars are charged at 20 kW or below. The fastest home charging on any Tesla is 20 kW. That's a function of what is practical at home with level 2 and not the same as the fast DC charging (level 3).

Tesla fast chargers, Superchargers, will charge a car at up to 120 kW. Other fast chargers typically are around 50 kW. Some new fast chargers will do up to 300 kW, there are only a handful of them in the world at this point and I don't think any cars will charge that fast yet.

At 25 kW it would take around 4-5 hours to fully charge a 100 kWh battery. The last bit goes a lot slower than the rest.

Well, I guess someone does, but not many. The cars being sold in quantity today have mostly 100 kWh batteries.

According to the table only two Tesla models are 100 kWh.

Are all buying only these two models ?

Not sure what you are looking at. The models S, X and 3 all have 100 kWh battery options and even then have several performance options with that.

Most Teslas sold today (meaning more than half) have the 100 kWh battery.. It was only in Q4 (if I recall correctly) Tesla came out with another battery option in the model 3 which sells 2.5 times as many as the S and X together.

Of course such power levels may cause MV line loading problems in
countries using 4 or 7 kV medium voltage lines.

Not a problem if they are being charged at night under control of the grid to prevent overloading.

Rick C.

- Get 6 months of free supercharging
- Tesla referral code - https://ts.la/richard11209

Rick C.

+ Get 6 months of free supercharging
+ Tesla referral code - https://ts.la/richard11209

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