NFPA ELECTRIC VEHICLE SAFETY FOR EMERGENCY RESPONDERS Module

NFPA ELECTRIC VEHICLE SAFETY FOR EMERGENCY RESPONDERS Module III: Vehicle Systems and Safety Features 3 -1

NFPA ELECTRIC VEHICLE SAFETY FOR EMERGENCY RESPONDERS Module III: Vehicle Systems and Safety. Features Module III Objectives Terminal Objective Describe the operation of P/HEV and EV systems. Enabling Objectives ● ● Define terms related to P/HEV and EV systems. Compare and contrast P/HEV’s and EV’s. List major components of P/HEV systems. List major components of EV systems. 3 -2

Definitions HEV Hybrid Electric Vehicle A vehicle that has both an internal combustion engine (ICE) and electric motor(s). PHEV Plug-In Hybrid Electric Vehicle A vehicle that has both an ICE and electric motors, and can recharge its batteries to full charge from an external electric power source. EV Electric Vehicle A vehicle which uses only electric motor(s) for propulsion. 3 -3

Video Vehicle Types 3 -4

Hybrid Electric (HEV) All hybrids use batteries and electric motors to reduce demand on the internal combustion engine (ICE). ● Allows better fuel economy. Toyota Prius ● ICE can shut down when not needed. ● Full Hybrids can drive short distances on electric power only (silent movement hazard). ● For response purposes, treat all hybrids the same. Honda Civic Hybrid 3 -5

Plug-In Hybrid Electric (PHEV) A hybrid vehicle that allows the battery to be charged via an external power source. • Increases battery charge 2012 Ford Escape • Increases range • Reduces dependence on the gasoline engine. 2012 Toyota Prius 3 -6

Electric Vehicle • Electric motors are the only means of propulsion. • Vehicle must be charged by an external power source. Nissan Leaf 3 -7

Extended Range Electric Vehicle • Electric motors provide the propulsion. • When battery is low, gasoline generator provides the electricity for the motor. Chevrolet Volt • For emergency response, treat as a PHEV with… • a gasoline engine • high voltage battery • electric propulsion • possible external power. 3 -8

HEV / PHEV / EV VEHICLE COMPONENTS 3 -9

Standard Components Internal Combustion Engine 12 Volt DC Battery 12 VDC battery can be located in various locations around vehicle. Common Locations: · Trunk / Cargo compartment · Under hood Less Common Locations: · Front wheel well · Under 2 nd Row seats 3 -10

Video 12 VDC and High Voltage Batteries 3 -11

High Voltage Batteries Battery Types Ni. MH Nickel Metal Hydride Lithium Ion Various Materials 3 -12

High Voltage Batteries Nickel Metal Hydride (Ni. MH) Battery ● Most common battery in existing hybrids. ● Less common in newer vehicles. ● Electrolyte is alkaline. 3 -13

High Voltage Batteries Lithium Ion (Li-Ion) Battery ● Most common in electric vehicles. ● Will be used more in future hybrids. ● Many different chemical variations. ● Different from Li-Ion batteries in home electronics. 3 -14

Video High Voltage Battery Construction 3 -15

High Voltage Batteries Small Cells in Series ● High voltage batteries are made of many small, lowvoltage cells. ● Small cells wired in series to multiply voltage. ● Ex: Four 1. 5 VDC batteries in series equals 6 VDC. 3 -16

High Voltage Batteries Location of Batteries in HEVs, PHEVs Generally located in rear of vehicle. Under 2 nd row seating in most SUVs and trucks, in trunk/ cargo area in most sedans. 3 -17

High Voltage Batteries Location of Batteries in EVs ● EV Batteries are larger and of higher voltage than P/HEV batteries. ● Usually located on the underside of the vehicle. 3 -18

High Voltage Batteries Service Disconnects ● Recommendations for use and required safety equipment vary by manufacturer. Consult appropriate ERG before using service disconnect. ● Located on the battery. ● Cuts off the battery from the high voltage system. Service disconnect will be addressed later in course. 3 -19

Inverter/ Converter Located under hood ● Found in vehicles using AC drive motors. ● Converts DC from HV Battery to AC to run motor. ● Converts AC from regenerative braking back to DC to charge HV Battery. 3 -20

Inverter/ Converter Located under hood Dangerous to penetrate cover with tools. ● Capacitors inside unit can store voltage for a period of time. ● If damaged, capable of rapid energy discharge that can cause severe injuries. 3 -21

DC/DC Converter DC-DC Converter (APM) for Chevrolet Volt ● Takes the place of the alternator. ● Converts DC from high voltage battery to 12 VDC to run vehicle’s low voltage systems. ● In some models the DC/DC converter is housed in the inverter/converter module. 3 -22

Video High Voltage Battery Relay 3 -23

EV/ HEV Cabling Color coded to SAE voltage levels ● Low Voltage: <30 Volts Often Red or Black ● Intermediate: 30 -60 Volts Usually Yellow or Blue ● High Voltage: >60 Volts Orange 3 -24

Medium/High Voltage Cabling Medium and high voltage should both be considered highly dangerous. For the purposes of this program, treat blue cables the same as high voltage orange. 3 -25

High Voltage Cabling Location ● Between the HV battery, HV components, and the electric motor. ● Typically routed along the underside of the vehicle and under hood. 3 -26

High Voltage Cabling Construction/Fault Protection If a cable is compromised or damaged, the system is designed to detect the damage and shut down. For safety, ALL high voltage cable should be considered energized during response operations. 3 -27

Electric Motors P/HEVs • Provide propulsion in some models. • Start and stop the ICE when not needed. • Recharge HV battery through regenerative braking and ICE. EVs • Provide propulsion and recharge HV battery through regenerative braking. 3 -28

Regenerative Braking A process used to capture energy from braking and help recharge the high voltage battery. ● During braking, wheels turn the electric motor, making it act as a generator and produce electricity. ● Electricity routed to HV battery to increase charge. Can damage HV system if towed in overhaul. 3 -29

Safety Systems P/HEVs and EVs have safety systems designed to automatically shut down the high voltage systems in the event of: ● Crash Impact ● Airbag Deployment ● Cabling damage ● Short Circuits Always treat HV systems as energized for maximum safety. 3 -30

Charging Ports • Used to connect a charging cord to the vehicle. • The charging components reside on the vehicle. • The charging unit is an interface between the power supply and the vehicle. 3 -31

Charging Stations 3 -32

Charging Stations Level II 120 VAC 8 -16 hours 240 VAC 3 -8 hours DC Quick Charge 480 VDC 20 -30 min. 3 -33

Level 1 Charging Station Level I 120 VAC 8 -16 hours ● Utilizes 120 VAC power. ● Uses standard household plug. ● Slowest rate of the three levels. ● Can accompany vehicle to charge it anywhere. 3 -34

Level II Charging Station Level II 240 VAC 3 -8 hours ● Utilizes 240 VAC power. ● Can be a fixed installation or portable unit. ● Faster than Level I systems. Typically 3 -8 hours depending on the size of the battery. 3 -35

J 1772 Plug and Receptacle ● SAE standardized for Level I and II charging. ● Multi-pin charging/ communication link between charger and vehicle. ● Conducts current. ● Relays charge status. ● Shuts down charging when battery “full. ” ● Prevents vehicle from moving when plugged in. 3 -36

DC Quick Charge Station DC Quick Charge 480 VDC 20 -30 min. ● Currently provides 480 VDC directly to the battery. ● New standards being developed, so this may change. ● Fastest charging system. ● Due to wiring requirements, availability, and expense, will likely be in commercial sites only. 3 -37

Activity 3. 1 P/HEV, EV Components You will be shown a series of slides, each with a picture of a component of a P/HEV or EV. You will be given a few moments to discuss and decide on the name of the component and its function. Be prepared to share your answer with the class. 3 -38

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Component High Voltage Battery Function The electrical storage system that provides power for vehicle systems. 3 -40

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Component High Voltage Cabling Function Wiring used to carry electric current from the high voltage battery to the electrical motor. 3 -42

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Component Inverter / Converter Function Devices which convert DC from the high voltage battery to AC to drive the motor. May also house DC-DC converter to step down high voltage DC to 12 VDC to run standard vehicle systems. 3 -44

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Component Charging Ports Function Electrical connections on a vehicle for connecting the high voltage battery to a charging source. 3 -46

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Component Manual Service Disconnect Function Cuts off the battery from the high voltage system. Refer to Manufacturer ERG before use! 3 -48

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Component J 1772 Connector Function Multi-pin communication link between charger and vehicle. 3 -50

Activity 3. 1 End of Activity 3 -51

Module Summary • There are several different types of P/HEVs and EVs. • Each one has specific components related to its electrical identify. • Familiarity with the types, components and differences will facilitate emergency operations. 3 - 52 3 -52