Re: GM
There are still a lot of those old two-stroke Jimmy diesels in service - mostly off-road and marine service. That's why Chevron still offers the old CF-2 oil.
Though the prime mover technology is relatively ancient - just like the mechanical guts of automotive engines, locomotive control systems are very high tech, especially when you consider that you are taking 3000 kilowatts of variable frequency AC out of the generator, rectifying it to DC, and then running it through an inverter that outputs variable frequency AC on the AC drive types. It's this inverter and additional controls that add significant cost. DC traction motors can use the power coming off the rectifier.
Interestingly, the Chevy Volt's architecture is similar to a diesel electric locomotive. The IC engine drives a generator that powers the electric drive. The IC engine has no mechanical connection to the drive wheels. What they added was a battery, but such a locomotive exists. I think it's called the "Green Goat" - a yard locomotive, which is an environment where a "hybrid" (battery and IC engine) can yield significant fuel use reduction.
Back when I was a grad student at the U. of Wisconsin Engine Research center we threw this idea around. The problem back then was the control technology, which was all based on mechanical relays, and there were only eight power settings. That wouldn't work on a car. Nowadays with solid state digital control technology the systems can provide better control granularity. They are cheaper to produce, weight less, and take up less space, but are more difficult and expensive to design, develop, and debug.
I don't know how long the two-stroke 710 will be viable. GE developed a new four-stroke engine for Tier 1, and it probably has a lot of development left. EMD will probably have to go with the H engine at some point. It's not dead. Not long after the sale, EMD made a deal with China for locomotives that will use the H. Most of the assembly will be done over there. In a sense they may be giving away their technology, but it will also fund additional development of the H.
Maybe they'll end up moving the whole company to China. That wouldn't surprise me.
Duke
There are still a lot of those old two-stroke Jimmy diesels in service - mostly off-road and marine service. That's why Chevron still offers the old CF-2 oil.
Though the prime mover technology is relatively ancient - just like the mechanical guts of automotive engines, locomotive control systems are very high tech, especially when you consider that you are taking 3000 kilowatts of variable frequency AC out of the generator, rectifying it to DC, and then running it through an inverter that outputs variable frequency AC on the AC drive types. It's this inverter and additional controls that add significant cost. DC traction motors can use the power coming off the rectifier.
Interestingly, the Chevy Volt's architecture is similar to a diesel electric locomotive. The IC engine drives a generator that powers the electric drive. The IC engine has no mechanical connection to the drive wheels. What they added was a battery, but such a locomotive exists. I think it's called the "Green Goat" - a yard locomotive, which is an environment where a "hybrid" (battery and IC engine) can yield significant fuel use reduction.
Back when I was a grad student at the U. of Wisconsin Engine Research center we threw this idea around. The problem back then was the control technology, which was all based on mechanical relays, and there were only eight power settings. That wouldn't work on a car. Nowadays with solid state digital control technology the systems can provide better control granularity. They are cheaper to produce, weight less, and take up less space, but are more difficult and expensive to design, develop, and debug.
I don't know how long the two-stroke 710 will be viable. GE developed a new four-stroke engine for Tier 1, and it probably has a lot of development left. EMD will probably have to go with the H engine at some point. It's not dead. Not long after the sale, EMD made a deal with China for locomotives that will use the H. Most of the assembly will be done over there. In a sense they may be giving away their technology, but it will also fund additional development of the H.
Maybe they'll end up moving the whole company to China. That wouldn't surprise me.
Duke
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