Hello All,
I’m doing a ride-on mower electric conversion for a fun winter project. An Arduino is going to be the brains of the system. I have no background in electronics or programming (so please excuse my non-technical English), which makes this project quite challenging. Basically I’ve been googling a lot, and from that trying to implement other peoples experiences in my project. My lack of knowledge makes me expect a lot of confusion, headaches and smoke, but I’m hoping to minimize the smoke, with some help from you guys.
Description and schematics below.
Here is where I need your help:
- Is the mosfets I’ve chosen good enough? (They will be mounted to large heatsinks with fans. The stall current of motors is unknown, but my code will shutdown power to each motor if current is more than 200A or if current is more than 130A for more than 5 sec. I plan to use PWM frequency of 31khz)
- Can I use a single mosfet driver for driving 5 mosfets in parallel? And is my driver chip up to the job?
- Can I use 0.1uf small ceramic disc capacitors for noise suppression on such a large motor? (I have copied what others have used for much smaller motors, not being able to find examples for high current motors)
- Do you see anything in my circuit that will cause smoke, simply not work or is redundant?
Any input is greatly appreciated
The project:
Ride-on mower with one motor for drive (mechanical gearbox, so only one direction speed control is needed) and one motor for blades/cutter-deck. Arduino will be controlling speed of motors and monitoring voltage, drive-motor current, blade-motor current, system current, rpm for motors, safety switch, brakes (mechanical brakes) and “reverse-selected”. User interface will be an Android phone communicating by Bluetooth with Arduino.
Progress:
I have written the code for Arduino and Android and it works with simulated sensor values. Almost all parts have been bought, and next step is assembly.
Important parts:
Arduino Uno R3
Motors: 24V, 130A continuous, 2600 rpm, series-wound DC (unknown: stall current)
Batteries: 4pcs. Marine deep cycle 12V 75ah, flooded type (connected for 24V)
Mosfets: 5 pcs. IRL 1404 in parallel for each motor. Datasheet: http://www.irf.com/product-info/datasheets/data/irl1404.pdf
Mosfet Driver: TC4422, one for each bank of mosfets. Datasheet: http://ww1.microchip.com/downloads/en/devicedoc/21420d.pdf
Power supply for each mosfet driver: http://www.ebay.co.uk/itm/130680030803?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
12V supply for Arduino, lights etc.: http://www.ebay.co.uk/itm/24V-to-12V-DC-DC-Car-Power-Supply-Converter-30A-New-/180743402619?pt=LH_DefaultDomain_3&hash=item2a1525747b
Current Sensors (200A each): http://www.ebay.co.uk/itm/110894073072?var=410115820134&ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
Relays for lights, reversing light, horn and contactors: http://arduino-direct.com/sunshop/index.php?l=product_detail&p=156