Veloce Racing Electric

 Our project focuses on enhancing the safety and reliability of our Formula Student Electric Vehicle (FSAE) through an Integrated High-Voltage Safety and Control System. This system includes four key circuits:

1.    Accumulator  Controller Unit (ACU) - Manages energy distribution, ensuring balanced power delivery while protecting the battery system under dynamic driving conditions.

2.    TSAL (Tractive System Active Light) Green Circuit - Signals high-voltage presence in the system, providing an immediate visual cue for the safety of drivers and team members.

3.    Voltage Measurement Circuit - Continuously monitors voltage levels across critical points, enabling real-time adjustments and proactive safety measures.

4.    Power Distribution Circuit - Efficiently routes power to all vehicle components, ensuring reliable operation of the electric motor, sensors, control units, and auxiliary systems.

These circuits work together to enhance vehicle stability, prevent potential hazards, and ensure that our FSAE operates within safe voltage limits at all times.

Why Did You Decide to Make It?

Safety is paramount in the Formula Student competition, especially in electric vehicles where high-voltage components present unique risks. We designed this safety system to meet the stringent competition requirements and to prioritize the well-being of our drivers and crew members. By creating an integrated safety solution, we aim to set a high standard for EV safety in student racing competitions, equipping our team with hands-on experience in managing complex high-voltage systems.

How Does It Work?

ACU (Accumulator  Controller Unit): The Accumulator Control Unit (ACU) is responsible for managing and controlling the various safety and operational functions of the vehicle’s high-voltage (HV) and low-voltage (LV) systems. It integrates three critical sub-circuits namely the

a. TS Measurement Circuit

b. Pre-charge Circuit

c. AMS-IMD Latch Circuit

To ensure proper handling of the vehicle’s accumulator system. The ACU safeguards against potential risks such as insulation faults, contactor welding, and improper voltage levels, using logic gates, comparators, and MOSFETs to control the system's responses under various fault and operating conditions.

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Voltage Measurement Circuit: The Voltage Measurement Circuit is divided into two sub-circuits:

a. TSAL Red Circuit

b. Discharge Circuit

These circuits monitor the high-voltage (HV) side, flash the TSAL Red LED when HV is present, and ensure that the capacitors are safely discharged when the system is powered off or in shutdown mode.

Voltage Sensing: A voltage divider (R1 and R2) scales down the HV to a manageable level for the LM358 op-amp (U1A), which serves as a comparator. When the HV exceeds a set threshold (e.g., 60V), determined by the reference voltage on the inverting input (adjustable via potentiometer RV1), the LM358 output goes high, indicating an over-voltage.

Discharge Control: A 2N7000 MOSFET (Q3), triggered by the Tractive System Active (TSA) signal, controls the discharge path, while an NC reed relay ensures automatic capacitor discharge when TSA is inactive.

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·TSAL Green Circuit: The TSAL provides an essential visual indicator of high-voltage presence. When the vehicle is in an active, high-voltage state, the TSAL lights up green, ensuring that the driver and team members can quickly assess the safety status at a glance.

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Power Distribution Circuit: The custom-designed Power Distribution Board (PDB) manages the low-voltage power harness of the electric vehicle, ensuring safe and efficient distribution of power across critical circuits:

1) Overcurrent Protection: Each circuit is protected with dedicated fuses to prevent overload and short circuits.

Status Indication: LED indicators monitor each power line, providing visual confirmation of active circuits and enabling quick fault detection.

2) Reverse Polarity Protection: Equipped with P-channel MOSFETs to prevent damage from reverse polarity connections, adding an extra layer of safety.

3) Optimized Wiring: Uses Polycab wires sized at 0.75 mm² and 0.5 mm² for different circuits, based on specific power demands, ensuring efficient and reliable power flow.

This PDB design is essential for delivering stable, controlled power distribution throughout the vehicle’s low-voltage systems, enhancing both performance and safety in competitive racing.

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