3-phase motor control
Archiver
Posts: 46,084
FYI
To do this you buy a three phase inverter drive of
sufficient rating and then use the stamp to send
control voltages to the inputs on the drive using a DAC
and op-amp. Or send serial data to the drive as most
will accept either RS-232 or RS-485. The stamp does not
have the processing power for three phase power
conversion. The above method is cheaper, believe me....
Inverter prices have come down a lot in the last
several years and many are available on EBAY for
cheap...
In using three phase inverters your connecting to the
grid, meaning your using lethal yes dangerous voltage
levels and currents, stick to commercially built
inverters. The dollars invested by companies to build
reliable drives is in the millions, do not think for a
moment that you will be able to build anything
approaching the complexity which are available for a
few hundred dollars ( I have purchased 3-5 hp drives
for 300-500 dollars) for less.
A basic stamp controlling them is cool !
Sincerely,
Ron
_______________________________________________________
_________________
Message: 21
Date: Fri, 16 Jul 2004 23:54:28 -0000
From: "edblancke2002" <cantonite@h...>
Subject: 3 phase inverter using Stamp2
I would like to make a 3 phase inverter for varaible
speed control of
small 3 phase motors using one of the Stamps. The 3
phase sine wave
generation process is well documented on various web
sites, and
requires an fast accurate variable timebase and lookup
table to drive
the IGBT's. It does not seem to be easily achieved
using a Stamp2.
Has anyone any experience or links on this topic ?
To do this you buy a three phase inverter drive of
sufficient rating and then use the stamp to send
control voltages to the inputs on the drive using a DAC
and op-amp. Or send serial data to the drive as most
will accept either RS-232 or RS-485. The stamp does not
have the processing power for three phase power
conversion. The above method is cheaper, believe me....
Inverter prices have come down a lot in the last
several years and many are available on EBAY for
cheap...
In using three phase inverters your connecting to the
grid, meaning your using lethal yes dangerous voltage
levels and currents, stick to commercially built
inverters. The dollars invested by companies to build
reliable drives is in the millions, do not think for a
moment that you will be able to build anything
approaching the complexity which are available for a
few hundred dollars ( I have purchased 3-5 hp drives
for 300-500 dollars) for less.
A basic stamp controlling them is cool !
Sincerely,
Ron
_______________________________________________________
_________________
Message: 21
Date: Fri, 16 Jul 2004 23:54:28 -0000
From: "edblancke2002" <cantonite@h...>
Subject: 3 phase inverter using Stamp2
I would like to make a 3 phase inverter for varaible
speed control of
small 3 phase motors using one of the Stamps. The 3
phase sine wave
generation process is well documented on various web
sites, and
requires an fast accurate variable timebase and lookup
table to drive
the IGBT's. It does not seem to be easily achieved
using a Stamp2.
Has anyone any experience or links on this topic ?
Comments
wrote:
> FYI
>
> To do this you buy a three phase inverter drive of
> sufficient rating and then use the stamp to send
> control voltages to the inputs on the drive using a DAC
> and op-amp. Or send serial data to the drive as most
> will accept either RS-232 or RS-485. The stamp does not
> have the processing power for three phase power
> conversion. The above method is cheaper, believe me....
>
> Inverter prices have come down a lot in the last
> several years and many are available on EBAY for
> cheap...
>
> In using three phase inverters your connecting to the
> grid, meaning your using lethal yes dangerous voltage
> levels and currents, stick to commercially built
> inverters. The dollars invested by companies to build
> reliable drives is in the millions, do not think for a
> moment that you will be able to build anything
> approaching the complexity which are available for a
> few hundred dollars ( I have purchased 3-5 hp drives
> for 300-500 dollars) for less.
I think you should be able to find a trobleshooting manual for some
drive and it would be worth the read.
There are different types of inverters from a simple 6 step to a PWM
to the newer high frequency IGBT drives. the old PWM units would
make the motors sing so loud it would hurt !
I seem to remember doing some checking with a multi meter on a drive
and the DC bus for the 230 drive was 450 volts.
If you are looking to regulate speed of a small motor, there are
quire a few ways. if you are looking for power, then E-Bay is
probably a better starting point.
IMHO
Dave