Exam 41: Electric Powertrains

Which of the following methods of charging a CEV from the grid is contact-free?

How many NMC cells are required to produce a pack voltage of over 80 VDC?

When a regenerative braking cycle is engaged in a vehicle with an electric powertrain, which of the following should be true?

Technician A says that the peak torque ratings for CEV traction motors exceeds that used in an equivalent ICE by a significant margin. Technician B says that CEV traction motors typically have higher power ratings than the ICEs used in an equivalent vehicle. Who is correct?

When a li-ion battery is charged, which of the following is true?

Which of the following li-ion cells has proven to be the most thermally stable?

Technician A says that using multiple battery banks in parallel increases the electrical energy density. Technician B says that CEVs use multiple battery banks in series to increase the nominal operating voltage. Who is correct?

What device performs the high speed switching required in a solid state inverter?

Technician A says that that some CEVs are driven by a single, longitudinally-mounted (inline) traction motor directly coupled to drive wheels. Technician B says that a CEV drive axle can use a pair of in-axle traction motors coupled to reduction gearing in each wheel assembly. Who is correct?

What would be the advantage of using a 9-phase traction motor over a 3-phase motor in a CEV?

Which of the following cities was the first to eliminate diesel engines from its transit bus fleet?

Which of the following is true of the traction motor/generator used in a CEV?

Which of the following correctly describes a typical CEV traction motor?

Where is a CEV string control unit (SCU) normally located?

What frequency AC is used on the North American grid?

Technician A says that li-ion packs are arranged in parallel to form a string. Technician B says that battery strings are arranged in series to form a bank. Who is correct?

Technician A says that a CEV pantograph can be a permanent station fixture. Technician B says that a CEV stationary pantograph can uses a flexible parallelogram to enable its contact rails to connect with contactors on the vehicle. Who is correct?

Which of the following best describes the source of the energy recovered during regenerative braking in an electric powertrain?

Where would you most likely find a pantograph on a CEV transit bus?

Technician A says that although the voltage is high in a CEV, there is usually insufficient available current to cause an injury. Technician B says that the RESS in a CEV can output HV exceeding 600 volts. Who is correct?