Modified Mechanical Structure Electric Bike Design Computation and Prototype Model Implementation

The aim of this paper is to investigate the design computation and prototype model implementation of a Modified Mechanical Structure (MMS) Electric Bike (E-Bike). It is the technology that allows the vehicle to operate with the assistance of electrical energy. All conventional cars will be converted to electric vehicles (EVs) in the future. EVs will be affordable to all types of people, allowing them to fly comfortably and safely. As a result, this paper proposes a design estimate and model implementation of the MMS E-Bike with the smallest number of parts, lowest expense, and lightest weight possible. The most important parts of the designed MMS E-Bike are the battery, MMS, BLDC motor, and electronic commutator with their controller. Because of its adapted mechanical frame nature, the designed E-Bike is low in cost and weight, and it can also go up to 25 kmph. Furthermore, the rider will be able to ride the built MMS E-Bike without any pain to their bodies and should be able to sit comfortably during their journey. In comparison to the Ampere Angel and DMW Electra 20 E-Bikes, the performance of the developed model is tested under various operating conditions, as well as their battery backup.

Device for Generating and Measuring Time Intervals

The article suggests a device that extends the functionality of the measuring devices such as generators and frequency meters. So these devices can be used as part of working standards in a complex for verification and calibrating stopwatches. The device consists of an electronic commutator and a component controlled by a microcontroller, which forms the required intervals of time and provides a necessary connection from the generator output to the frequency counter input, turned on in the pulse counting mode. The control signal simultaneously arrives at the commutator and the device for automatic start/stop of stopwatches. The circuit design of the device allows minimizing the device’s influence on the overall metrological characteristics of the complex through the use of a high-speed controlled M74HC125 buffer (high-speed CMOS QUAD BUFFER (3-STATE)) as a switch. The M74HC125 buffer in this device is the only metrologically significant node; the state switching time of which in the aspect of this task can be ignored (Fig. 3). A computer and standard software, such as HyperTerminal from the Windows XP or PuTTY distribution, are used to control and communicate with the device. The device can be connected to the computer via USB. For laboratories that have these instruments in operation, this approach can help to avoid acquisitions of the additional reference equipment, which helps to reduce the maintenance and calibration costs of reference equipment.

Design and Fabrication of Electric Vehicle for Physically Challenged Person

This article studies on a design and fabrication of Electric Vehicle (EV) for physically challenged person. In current scenario, a physically challenged person has facing a problem of transportation during their travel from one place to another place without safety and convenience. They find it difficult to react to situation in front of them. In order to solve these problems, an Electric Vehicle (EV) is designed where they can travel easily and safely. The major components of EV consist of battery, electronic commutator with control unit, BLDC motor and mechanical structure. The main merits of developed EV has no pollution, no fuel cost, less weight, modified mechanical structure, high pulling capacity, comfortable spacing for person travel, easy maintenance, less number components in comparison with existing EV. The gross weight of designed vehicle with load (person) has 300 kg (approximately). The performance of the developed EV is validated at different running conditions for monitoring the battery back-up and time durations.

Constant Current Models of Brushless DC Motor

Two constant current models of Permanent Magnet Brushless Direct Current Motor (PM BLDC) are presented in the paper. In the first part of the paper principle of operation, basic properties and mathematical equations describing PM BLDC models are given. Then, two different constant current models of PM BLDC motor are considered: In the first model, PM BLDC motor is approximated with dc motor; in the second model, modified constant current model is applied with additional block, which is used to take into account the impact of inductance on torque-speed characteristics. In order to verify these models, torque-speed characteristics have been determined and compared for different motor supply voltages. After running a series of simulation and laboratory tests, we have found that this modified model (which makes allowance for the influence of inductance on torque-speed characteristics) ensures obtaining torque-speed characteristics identical to those of the real motor. Therefore, this model may be recommended for those simulation tests which do not consider effects occurring inside the electronic commutator-motor circuit. However, approximation of PM BLDC motor with dc motor is not recommended in computer tests.

A reconfigurable structure electronic commutator for a dual BLDC motor EV drive

An electronic commutator that can drive a PM BLDC motor either in the full bridge or half bridge configuration has been developed. This commutator allows increasing the motor speed over the nominal value, hence the motor is able to operate within a wide constant power speed range. An application of the commutator with a reconfigurable structure for the double drive of a small electric vehicle Elipsa has been presented. The driveline consists of two independent commutators feeding the motors coupled by gears with rear wheels of the vehicle. Both commutators are controlled by a common control system based on a signal microcontroller. The results of road tests indicate new areas of BLCD motor drives application. The fact that the BLCD motor work in the second speed range does not require any changes in the motor construction and at the same time does not significantly deteriorate the drive efficiency is an indisputable advantage of the presented solution

Recovery braking of variable-structure electronic commutator for BLDC motor

Permanent magnet motors are more and more frequently used in various applications. In this group motors with a trapezoidal EMF deserve a special attention. They are characterized by a simple construction, high efficiency and high torque overload. A certain drawback of BLDC motors are difficulties with an operation at a speed above the nominal value. The article presents the results of investigations into the variablestructure electronic commutator designed for the drive of a small electric vehicle equipped with BLDC motors. Such a solution allows extending the standard range of the drive’s speed. The considerations contained in the article focus on the possibilities and effects of regeneration mode in the proposed topology of converter. A theoretical analysis has been presented as well as computer simulations carried out by means of Matlab- Simulink, which were then verified at a laboratory. The tests were finished with trials conducted using a small electric vehicle Elipsa.