Requirement\3 Electrical and propulsion systems

1.3 Electrical and propulsion systems
1.3.1 Vehicle electrical system
1.3.1.1 Voltage (on-board batteries, external batteries, super capacitors, etc)
1.3.1.1.1 Maximum voltage must never exceed 48 V nominal.
1.3.1.1.1.1 Maximum voltage must never exceed 60V max (peak).
1.3.1.2 Lithium ion battery.
1.3.1.2.1 The BMS must protect over-discharge (for e-mobility vehicles).
1.3.1.2.2 For non e-mobility vehicles, the accessory battery BMS system cell balancing and overcharge protection may be contained in the off-board charger.
1.3.1.3 All batteries and super capacitors must be short circuit protected.
1.3.1.3.1 Protection may be in the form of a fuse, fusible link, or a current interrupting device (circuit breaker).
1.3.1.3.2 Automatic reclosing current interrupting devices are not allowed.
1.3.1.3.3 Short circuit protection devices must be located on the positive and as close as possible to the battery itself.
1.3.1.3.3.1 The rating of the short circuit protection device must be such that the battery will be able to supply enough short circuit current at all times to open the device.
1.3.1.4 All vehicle electrical circuits must be protected against electrical overload.
1.3.1.4.1 Overload protection may be in the form of fixed current limits within electric controllers or by the insertion of individual circuit fuses.
1.3.1.5 Hybrid and e-mobility vehicles which have a propulsion battery.
1.3.1.5.1 Propulsion battery or super capacitors must be electrically isolated on both positive and negative circuits.
1.3.1.5.1.1 Must be isolated from the vehicle frame.
1.3.1.5.1.1.1 Must be isolated from the accessory battery circuit.
1.3.1.5.2 (for e-mobility vehicles only) Only one propulsion battery is allowed.
1.3.1.5.3 Only one accessory battery per vehicle is allowed.
1.3.1.5.3.1 The accessory battery (refer article 57 h) must maintain a negative ground.
1.3.1.5.3.2 The accessory battery must operate all safety devices (e.g. horn, hydrogen sensor) for the duration of the competition.
1.3.1.5.3.3 The accessory battery may also operate for: internal combustion engine, the starter motor, the ignition, the instrumentation and electronic management systems.
1.3.1.5.3.4 All other additional sources of electricity are forbidden.
1.3.1.5.3.5 The accessory battery is not allowed to power compressors, blowers, engine cooling systems, motors, etc. It may however be used to power a ventilation/cooling fan for the driver.
1.3.1.5.3.6 The organizers reserve the right to request Teams to install one joule meter, intended to measure the quantity of energy provided by the accessory battery. If this amount of energy exceeds the power typically required to operate the starter motor, horn and safety devices the competitor will be disqualified.
1.3.1.5.4 Both propulsion and accessory batteries must be installed outside of the driver's compartment behind a bulk head (see article 27).
1.3.1.5.5 The following devices may be powered by batteries other than the propulsion or accessory battery provided they use built-in batteries: radio communication system, GPS system, data loggers excluding engine management units, driver ventilators.
1.3.1.6 All electrical/electronic cases must be made of transparent material or at least have a transparent top.
1.3.1.7 Must have a Battery Management System (BMS) installed to control and protect the battery against risk of fire. The BMS must provide cell balancing during off-track charging and protect against overcharge,( and for e-mobility vehicles) over discharge, over-current and over temperature. For non e-mobility vehicles, the accessory battery BMS system cell balancing and overcharge protection may be contained in the off-board charger.
1.3.1.7.1 The BMS must provide cell balancing during off-track charging.
1.3.1.7.2 The BMS must protect against overcharge.
1.3.1.7.3 The BMS must protect against over-current.
1.3.1.7.4 The BMS must protect against over-temperature.
1.3.2 Battery electric vehicles
1.3.2.1 The drive train in the "Battery Only" category has restrictions to electrical storage and motors.
1.3.2.1.1 Maximum two electrical motors, with associated control units.
1.3.2.1.2 One electric storage device.
1.3.2.2 The competitors must provide a description and a precise technical drawing of their electrical drive train with the application.
1.3.2.3 Batteries
1.3.2.3.1 Only Lithium-Ion batteries are permitted as electric storage devices.
1.3.2.3.2 The vehicle must be equipped with a Battery Management System (BMS) to control and protect the battery against risk of fire as defined in article 57.
1.3.2.3.3 The Lithium-Ion battery and any accessory circuits are subject to the maximum voltage defined in Article 57 a).
1.3.2.4 The entire drive train including all circuit protection must be easily accessible for inspection and measurements.
1.3.2.5 Batteries must be placed outside the driver's compartment behind the bulkhead and securely mounted (see Article 27).
1.3.2.6 All vehicles must be equipped with one joule meter located between the battery and the motor controller(s) to measure the electric motor energy consumption.
1.3.2.6.1 The organizers will provide this joule meter for the duration of the event. A security deposit may be required for the joule meter.
1.3.2.6.2 The joule meter must be positioned so that its display can be easily read from outside the vehicle.
1.3.2.6.3 The joule meter must be inaccessible to the Driver in his or her normal driving position.
1.3.2.7 The competitors will be required to present electrical schematics at the competition technical inspection.
1.3.3 Horn
1.3.3.1 Each vehicle must be equipped with an electric horn mounted towards the front of the vehicle, in such a manner that is effectively audible to other vehicles and track marshals.
1.3.3.2 Volume and pitch
1.3.3.2.1 The horn must have a high tone (pitch) of equal or greater than 420 Hz.
1.3.3.2.2 With the vehicle in normal running condition, the horn must emit a sound greater than 85 dBA when measured 4 meters horizontally from the vehicle.
1.3.3.2.3 The horn must have a noise capability/volume greater than 110 dBA.
1.3.4 Emergency shutdown
1.3.4.1 The emergency shutdown mechanism (ESM) must provide a physical isolation of the propulsion battery from the vehicle electrical system.
1.3.4.1.1 If relays are used in the ESM, the relays must be a normally open contact type.
1.3.4.1.2 The use of a power controller or other logic systems to drive an isolation device is not permitted.
1.3.5 Team
1.3.5.1 Control system
1.3.5.1.2 Must have robust and stable velocity control of the motor, providing energy-optimized running. All new functionality requested by Shell rules must be implemented. Also, communication between control system and SmartMotor must be tailored (new black box, how do you want this formulated?). Horn, lights and wipers must be included in the car control system.