हाटे-बाजारे एक्सप्रेस : चलती - फिरती मछली बाजार - Piyush Singh

Diesel Locomotive can't be Off like Present Diesel locos but Electric One can be Easily Switch Off or on.
As we know Diesel Engine continuously runs
When It Will run in Electric Section Its Power will be
4500 Hp + 4500 Hp Becomes = 9000 Hp Loco More Powerful than WDG5's 5500 Hp n WAP7's 6000 Hp n WAG9's 6850 Hp Most...
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Powerful Loco of IR
Ya In Diesel Lines It will act as Simple WDP4D

The 4500HP rating comes from the motor ratings. So a Co-Co loco of 4500HP will have something like 6 750HP traction motors ( Not exact numbers, just an example, some part of the power is required for on board stuff, reducing the power available to the motors), giving it a total of 4500HP. This amount will be the same no matter how much power is supplied to it. ( It is possible to get higher power rating of about 300-500HP higher, but only for a short period). So even if the diesel engine and OHE work in parallel, the motors cannot supply more than 4500HP of power. And in the dual mode loco, there will only be 6 traction motors that will be powering the axles.
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Besides, connecting 2 AC power sources ( in this case, one OHE and one diesel generator) is a very tricky task. Even the slightest difference in the voltage, frequency or phase, can cause a great power imbalance on the power grid and can cause very messy problems. And moreover, the control systems for both are different and using both will be quite unstable. Basically, it's a very, very tedious problem to solve, and can make the locomotive extremely expensive.
These locomotives are designed for a very specific market. Their usage pattern will be like this. At the point of traction change from diesel to electric, the diesel engine will be powered down and the control will be shifted to the Pantograph and electric loco portion. The diesel engine may be switched off completely, or may be running in idle mode, disconnected from the rest of the loco. At a point of traction change from diesel to electric, the control will be handed over to the diesel portion again and the OHE power block will be isolated. This will require a reasonably long halt, but it will be less time consuming than changing a loco.
These will be only used for trains that run for most part of their journey on one traction and have to do a small part of their journey on another. They are not designed for being used as regular locos like the WAP or WAG series.