Embedded Systems and Design & Development - Feb 20, 2026 | Morning | VisionAstraa EV Academy

Introduction to Lab Setup

Overview of the Session

• The session is introduced, emphasizing the importance of practical exposure for online attendees.

• The aim is to showcase the lab setup and provide insights into practical sessions that participants may miss.

Lab Equipment and Motor Control

Motor Specifications

• Discussion on a specific type of motor kit, including its RPM and control systems.

• Explanation of battery management systems (BMS), energy supply, and motor transmission types (forward, reverse, neutral).

Battery Monitoring

• Display features include current speed, battery status (71% charged), and peak capacity details.

• Emphasis on understanding battery metrics for effective usage in practical applications.

Controller Types and Functionality

Controller Insights

• Introduction to two types of controllers essential for electric vehicles (EV).

• Mention of fault simulation capabilities within the system.

Emergency Features

• Description of emergency brake functionalities and their significance in safety protocols.

Charging Systems Explained

Charging Port Details

• Overview of charging ports used in the lab setup with specifications on input/output voltage.

• Information about common household voltage requirements (230V), output current specifications (6.0A).

Battery Pack Usage

• Discussion on a specific battery pack type used without BMS for practical demonstrations.

Advanced Motor Features

Six-phase PMS Motor Design

• Explanation regarding the six-phase PMS motor designed specifically for this kit.

Comparison with Other Phases

• Clarification on why six-phase motors are preferred over three-phase motors due to efficiency in operation.

Practical Demonstration Insights

Operational Modes

• Description of operational modes including neutral state and ignition key functionality.

Acceleration Metrics

• Real-time demonstration showing acceleration capabilities up to 62 km/h while discussing voltage readings during eco mode.

Understanding Six-Phase Motors and Their Applications

Maximum Speed and Current Specifications

• The maximum speed for the discussed motor is noted to be 62.

• The current specifications are also emphasized, indicating that it should be recorded alongside voltage.

Input Supply for Six-Phase Motors

• A question is posed regarding the input supply voltage for a six-phase motor, inviting audience participation.

• Responses from participants suggest various voltages, with one mentioning 800 volts.

• Clarification is provided that the typical supply voltage is around 400 volts, similar to three-phase motors.

Efficiency and Switching Frequency

• The efficiency of six-phase motors is highlighted due to their higher switching frequency resulting from a 60° phase shift.

• It’s confirmed that while the voltage remains consistent at approximately 400 volts, the operational efficiency improves.

Modes of Operation

• Discussion transitions into different operational modes of the motor, including normal and sports mode settings.

• In sports mode, specific values such as current (20.4 amps) and single-phase voltage (53.6 volts) are mentioned.

Control Systems in Electric Vehicles

• Inquiry about knowledge on control systems used in four-wheelers indicates a focus on how these systems manage six-phase motors.

• Participants are asked about VQ and WD parameters related to control algorithms; responses indicate familiarity with direct access concepts.

Reverse Mode Functionality

Speed Limitations in Reverse Mode

• The maximum speed achievable in reverse mode is stated as 14 km/h due to safety concerns regarding control.

Voltage Consumption Insights

• Voltage consumption during reverse operation is lower because of reduced speed; current ranges between 2.1 to 2.3 amps.

Choosing Modes for Optimal Mileage

Comparison of Operational Modes

• A question arises regarding which mode offers better mileage: eco, normal, or sports mode.

Audience Participation on Mileage Preferences

• Responses indicate that eco mode provides the best mileage despite sports mode being more powerful but less efficient in terms of battery usage.

Two-Wheeler Motor Setup Overview

Introduction to Two-Wheeler Motor Types

• An introduction to two-wheeler setups highlights mid-drive motors; further details about specific types are anticipated from participants.

EV PMS Motor Trainer Kit Overview

Introduction to the Kit

• The session introduces the EV PMS motor trainer kit, which is designed for educational purposes in understanding electric vehicle systems.

• The setup includes a DC motor that loads the system, showcasing different operational modes.

Modes of Operation

• The kit features various modes: high, mid, and low, along with forward and reverse functionalities for two-wheeler setups.

• Participants express interest in exploring these modes, indicating engagement with the practical demonstration.

Understanding Key Components

Electrical Measurements

• The kit is equipped with multiple measurement tools: DC voltmeter, DC ammeter, AC voltmeter, AC ammeter, and an RPM meter to monitor performance metrics during operation.

• An ignition key is used to power on the system before starting demonstrations across different modes.

Role of Hall Effect Sensor

• A Hall effect sensor is utilized to synchronize the stator and rotor positions in the synchronous PMS motor for optimal speed control. This ensures both components are aligned correctly for maximum efficiency.

• The RPM sensor tracks real-time speed data displayed on the RPM meter during operation.

Operational Demonstration

High Mode Performance

• In high mode, the battery voltage measures approximately 48 volts, drawing a current of about 3.9 amps from the battery pack while achieving maximum rotation speed indicated by significant vibrations from the motor.

• Observations include noting down critical values such as voltage consumption and current draw during this mode for analysis later on.

Transitioning Between Modes

• As operations shift from high mode to medium mode (normal), voltage remains stable at around 46.8 volts, but current draw decreases to approximately 3.3 - 3.7 amps while RPM readings drop to around 2,200 RPM.

• In low or eco mode, despite lower speeds expected, current draw increases significantly up to about 5.35 amps, raising questions regarding torque requirements at lower speeds compared to higher settings where less current was drawn despite higher speeds achieved earlier in high mode operations.( t = 2500 s )

Analysis of Current Draw Across Modes

Current Draw Insights

• Participants are prompted to recall specific values observed during high-speed operations; notably that high mode drew around 3.8 - 3.9 amps while mid-mode saw similar currents around 3.x amps .

Understanding Torque Implications

• Discussion arises regarding why low mode draws more current than expected; participants suggest it relates primarily to increased torque demands even without additional load applied.( t = 2676 s )

Understanding Motor Torque and Current Draw in Different Modes

Low Speed Mode Dynamics

• The RPM is lower in low mode, while high mode shows around 233 RPM, indicating no significant difference in electromagnetic torque.

• In stationary mode, the vehicle requires more torque initially due to lack of momentum, leading to higher current draw at low speeds.

• When loading the motor with weight (e.g., 50-60 kg), it’s essential to consider how this affects performance.

Current Draw Measurements

• After loading the motor, the voltage remains stable at 48.5V; however, current draw increases significantly in low speed mode.

• The DC ammeter indicates a current draw of approximately 9 amps at low speed.

• Transitioning from low to mid mode should ideally decrease current; however, measurements show mid mode draws about 6.2 amps.

High Speed Mode Observations

• In high speed mode under similar load conditions, the current draw decreases further to around 5.4 amps.

• There is confusion regarding why mid and high modes show similar current readings despite expectations for variation.

Forward and Reverse Mode Functionality

• Observations are made on forward and reverse motor operation; clarity on directionality is confirmed as clockwise for forward and anticlockwise for reverse.

• In reverse mode, the DC ammeter reads approximately 1.73 amps with an RPM of around 570.

Power Electronics Overview

• A universal breadboard model is introduced for power electronics applications; understanding its components is crucial for grasping system functionality.

• PWM controllers are highlighted as key elements in controlling voltage supply effectively within a range suitable for motors.

• Components like diodes ensure unidirectional flow of energy while capacitors play a role in energy storage within circuits.

Understanding the Buck Converter Circuit

Overview of Buck Converter Components

• The buck converter circuit utilizes a capacitor voltage supply, which is a form of DC to DC conversion. This setup allows for controlled output from the DC supply.

• The circuit design includes components that allow current to flow in one direction while opposing reverse current, ensuring efficient energy transfer.

• An inductor is introduced as a key component, serving to store electric energy in a magnetic field. It charges and discharges slowly, which helps regulate current flow.

Load and Power Supply Configuration

• Common loads such as motors or batteries can be connected to the buck converter circuit, demonstrating its versatility in various applications.

• The input from the DC supply is directed into the capacitor, which operates effectively under variable conditions ranging from 0 to 72 volts.

Circuit Connections and Functionality

• A PWM (Pulse Width Modulation) signal is supplied to control the gate and source connections within the circuit. This interconnection facilitates proper functioning between components like inductors and diodes.

• Shorting occurs at specific points between sources and inductors, indicating critical junctions where energy transfer takes place efficiently.

Inductor-Capacitor Interaction

• The interaction between inductor negative terminals and capacitor positive terminals illustrates how energy flows through the system towards load outputs like motors.

• Direct grounding connections are established for effective power management without unnecessary complications in wiring configurations.

Frequency Settings and Voltage Control

• Discussion on frequency settings reveals that common switching frequencies used are around 50 Hz; however, higher frequencies up to 500 Hz can be achieved with this kit for optimal performance.

• Voltage adjustments are made based on user requirements; options range from 0 to 72 volts with practical examples provided during discussions about motor operation needs.

Duty Cycle Management

• PWM is utilized not only for voltage variation but also for setting duty cycles essential for controlling load safety during operation.

• The importance of turning on/off outputs via buttons ensures that voltage is only supplied when necessary, enhancing operational safety within the circuit setup.

Understanding Buck Converters and Motor Control

Introduction to Voltage Reduction

• The discussion begins with the concept of voltage reduction, specifically how a multimeter displays a voltage of 3.6 volts while the motor is not running.

• When the duty cycle is increased to 50%, the motor starts operating, demonstrating that reducing voltage can effectively control motor function.

Duty Cycle and Voltage Conversion

• At a 50% duty cycle, the output voltage drops to approximately 24 volts from an input of 48.1 volts, illustrating the conversion process in a buck converter.

• The relationship between input and output voltages is emphasized; halving the input (48 volts) results in an output of 24 volts when using a buck converter.

Operational Mechanics of Buck Converters

• The device operates by turning on at a duty cycle of 50%, allowing for effective power management and conversion from higher to lower voltages.

• A visual representation will be provided later to clarify how this conversion occurs within the system.

Experimentation with Battery Banks

• Transitioning into practical applications, an experiment involving two battery banks connected to a charger is introduced.

• A larger setup will be demonstrated where input from batteries is converted for use in motors, showcasing real-world applications of buck converters.

Motor Operation and Control

• The motor requires a specific voltage (24V), which it receives through conversion from a higher voltage battery pack (48V).

• Throttle control allows students to observe direct effects on motor operation as they engage with the system.

Components Used in Larger Setups

• Discussion includes components like MOSFETs arranged on universal breadboard modules for ease of experimentation.

• Key components such as diodes, capacitors, and motors are integrated into larger setups for educational purposes.

Importance of PWM in Motor Functionality

• Emphasis on Pulse Width Modulation (PWM); without it, motors do not operate despite being powered.

EV Charging Stations Comparison

• An analogy is drawn between national highways requiring toll payments and future electric vehicle charging stations that may implement similar fee structures for usage.

Understanding the Control Diagram of a Public Charging Station

Overview of AC Supply and Noise Filtering

• The system receives an AC supply ranging from 180 to 240 volts, typically considered as 220 to 230 volts.

• A display AC voltmeter is used to monitor the voltage; noise present in the AC signal necessitates the use of a noise filter for reduction.

Rectification Process

• A rectifier converts AC to DC, which is essential since the charge stored requires DC voltage.

• Post-rectification, some noise or disturbances remain in the DC output that must be smoothed out.

Voltage Requirements and Conversion

• The required output voltage for charging is between 30 to 60 volts DC; this is achieved through further conversion processes.

• Depending on whether the post-smoothing voltage exceeds or falls below these thresholds, either a buck converter (for higher voltages) or a boost converter (for lower voltages) will be employed.

Role of Microcontrollers in Embedded Systems

• A microcontroller is utilized for programming and interfacing within the embedded system setup.

• It’s highlighted that while both boost and buck converters can be used, only step-down conversion is necessary due to battery voltage constraints.

Current Management During Charging

• The input current at 230 volts AC needs careful management; while it starts at around 3 amps, it may increase up to 6 amps during charging.

• Emphasis on increasing current rather than voltage during charging illustrates fundamental principles of electrical engineering relevant to battery management.

Operational Steps for Charging Setup

• Initial steps include switching on power supplies like MCB and RCCB before connecting chargers to battery banks.

• Once connected, indicators show operational status; initial readings indicate approximately 53.3 volts being supplied but not yet charging due to battery state.

Battery Status Monitoring

• The charger does not initiate until specific conditions are met (e.g., tapping a card), indicating readiness based on internal charge levels.

• After discharging through usage, monitoring shows that batteries are not fully charged but are receiving power effectively from the charger setup.

This structured overview provides insights into how public charging stations operate regarding their control diagrams, focusing on key components such as rectification processes, voltage requirements, microcontroller roles, current management strategies during operation, and practical steps involved in setting up a charging station.

AC Voltage and Current Measurements

Overview of AC Measurements

• The session discusses the measurements of AC voltage and current, noting a reading of 241 volts on the voltmeter and approximately 2 amps on the ammeter.

• It is explained that when connected to a battery bank, the current shows around 3 amps while stepping down to 54 volts.

RFID Card Functionality

• The instructor demonstrates how removing the connection will turn off the system, indicating that an RFID card must be tapped for charging to commence.

• The importance of tapping the RFID card is emphasized as it activates the charging process.

Understanding Lab Setups

Importance of Physical Setup

• The instructor highlights that online students miss out on hands-on experience with lab setups, which are crucial for understanding practical applications.

• Various setups are shown in VU Baragavi and VU Nagari, where students engage in disassembling and assembling components.

Role of Common IDs

• Discussion about how each component (battery bank, power bank, RFID card) must share common IDs for proper functionality.

• Tapping the RFID card allows it to analyze stored information before initiating charging.

Experiments and Learning Outcomes

Student Engagement in Experiments

• Students are encouraged to document their experiments related to buck converters and EV charging technology in their diaries.

• Mechanical engineering students can describe two-wheeler setups while electrical students focus on motor types and phase signals.

Future Sessions

• The session concludes with plans for future meetings, emphasizing continued learning opportunities through hands-on experiences.

• An afternoon session is scheduled for further discussions on covered topics.