Do any new trains still use DC motors?

Question

I'm not refering to trains that take DC power and invert to ac to drive the motors. I mean that are not built with AC/Three Phase motors (or for the pedants - mechanical drives)

Answer 1

Huh??

Your question and the explanation of same don't match.

Edit:

I understand.  You mean motors used for traction.

For freight operations, Both AC and DC locomotives are built today.  The purchase decision is made looking at the purchase price and the utilization.

The AC locomotives are ust a bit more expensive to buy, but for railroads that need a lot of low-speed TE for the highest tonnage (like coal trains), they are an overall benefit (fewer units needed per train).

If you were a railroad with lower tonnage and higher speed operation (manifest freight), it would not be prudent to spend extra for AC.  DC locomotives are just as good, and they are simpler to troubleshoot, too (familiarity).  Remember, the ease of maintenance of the AC motors is more than offset by the complexity added in the inverters needed to drive them.

Answer 2

all london underground trains use DC motors 630-700v dc

Answer 3

I agree with Rango.They still make both types.The one thing i do like about them is the ability to cut out single traction motors to comply with dynamic brake restrictions.Our first series of G.E. Evo engines had a lot of computer software issues.The first series of ac's were a pain.I still hate seeing them in a consist too.Just had an old SP 222 on the point of a dpu double stack train.They take forever to start loading.Makes good train handling a pain!

Answer 4

Most new locomotives are AC, probably not all of them.

Speaking form an engineer's point of view, I am not in the least convinced that AC is a bit better than DC locomotives.

The first series of AC we saw were worse, I hate seeing those older series in a consist on a heavy train.

The newer generations including the EMD ACE and GE Evo series are good, very good but other than being new and quiet I dont see any improvement in traction control, dynamic braking abilities, or reliability.

They may have benefits in maintenance or fuel economy, I honestly cant say.

Answer 5

Jubilee Line.

Answer 6

Most are swapping to AC Traction Motors. A Traction Motor converts electricity generated by the diesel engine into power to move the wheels.

AC Traction used alternating current. It uses AC power for things like dynamic braking. Thats where the motors become giant resistors and send the electicity back through the engine, and it is exhausted as heat. On the rear of modern diesels. They have what is called a "rad cab" thats where the fan is.

Dynamic braking is commonly used for trains goin downhill. That way the trains wouldn't burn up there brakes.

I know that and I'm only 17!!!