logo-mobile

ROHM

ROHM
Menu
  • Arduino –
  • Raspberry Pi –
  • Trending –
  • Others –
  • About –
  • Contact –

Glossary

Maximum Current Flow to Motor

Device Plus Editorial Team
Published by Device Plus Editorial Team at July 14, 2016
Categories
  • Glossary
  • Others
Tags
  • motor
Current Flow

Figure 1. Brush DC motor equivalent circuit

Question: Under what conditions does the maximum amount of current flow through the motor?

Answer: Maximum current flow occurs when there is no load in one direction and the motor is operating at maximum speed, at which time operation will immediately reverse direction.

An equivalent circuit of a DC brush motor is shown in Figure 1, while Figure 2 shows the power supply polarity conditions immediately before and after change when the DC brush motor is operating at maximum speed.

Current Flow

Figure 1. Brush DC motor equivalent circuit

Ea:Supply Voltage

Ia:Motor Current

R:Armature Resistance

L:Coil Inductance

Ec:Motor Generated Voltage

Current Flow polarity reversal

Figure 2. DC brush motor equivalent circuit diagrams immediately before and after polarity switching at maximum motor speed

(a) Immediately before
polarity reversal               (b) Immediately after polarity reversal

A DC brush motor can be represented as a series-connected circuit with a resistor, inductor, and motor-generated voltage. When the motor reaches its maximum speed under no-load conditions, the generated motor voltage also becomes maxed out, with a value Ecmax (see Figure 2 (a) above). At this time the power supply connected to the motor reverses directions in order to reverse motor rotation (Figure 2 (b)). The supply and generated voltages are added and applied to the series motor circuit consisting of the resistor and inductor. This will result in maximum current flow during motor operation.

With a maximum current Ipk,

Ipk=(Ea+Ecmax)/R

of DC current should flow, but since the inductance will act to prevent instantaneous current change and the current will steeply rise with respect to time, this maximum value will not be reached.

With respect to the direction of rotation, when the motor current flow is in reverse, torque works in the reverse direction, reducing rotational speed (RPM). The generated motor voltage is proportional to the rotational speed. As a result, when the generated voltage decreases the current flow to the motor will also decrease. These transient waveforms are shown in Figure 3.

Current flow waveforms

If you have any comments or questions, please leave them for us at Google +. Follow us there; we will be posting more soon.

Device Plus Editorial Team
Device Plus Editorial Team
Device Plus is for everyone who loves electronics and mechatronics.

Check us out on Social Media

  • Facebook
  • X

Recommended Posts

  • Motor Current When Applying a Torque LoadMotor Current When Applying a Torque Load
  • Simple DC Brush Motor ControlSimple DC Brush Motor Control
  • Power Consumption During Current Regeneration FlowPower Consumption During Current Regeneration Flow
  • How To Calculate Power ConsumptionHow To Calculate Power Consumption
  • Maximum Rated Output CurrentMaximum Rated Output Current
  • How To Make Parking Assist Car SensorsHow To Make Parking Assist Car Sensors
Receive update on new postsPrivacy Policy

Recommended Tutorials

  • How to integrate an RFID module with Raspberry Pi How to integrate an RFID module with Raspberry Pi
  • How to Use the NRF24l01+ Module with Arduino How to Use the NRF24l01+ Module with Arduino
  • How to Run Arduino Sketches on Raspberry Pi How to Run Arduino Sketches on Raspberry Pi
  • Setting Up Raspberry Pi as a Home Media Server Setting Up Raspberry Pi as a Home Media Server

Recommended Trends

  • SewBot Is Revolutionizing the Clothing Manufacturing Industry SewBot Is Revolutionizing the Clothing Manufacturing Industry
  • All About The Sumo Robot Competition And Technology All About The Sumo Robot Competition And Technology
  • 5 Interesting Tips to Calculating the Forward Kinematics of a Robot 5 Interesting Tips to Calculating the Forward Kinematics of a Robot
  • Go Inside the Drones That Are Changing Food Delivery Go Inside the Drones That Are Changing Food Delivery
Menu
  • Arduino –
    Arduino Beginner’s Guide
  • Raspberry Pi –
    Raspberry Pi Beginner's Guide
  • Trending –
    Updates on New Technologies
  • Others –
    Interviews / Events / Others

Check us out on Social Media

  • Facebook
  • X
  • About
  • Company
  • Privacy Policy
  • Terms of Service
  • Contact
  • Japanese
  • 简体中文
  • 繁體中文
Don’t Forget to Follow Us!
© Copyright 2016-2023. Device Plus - Powered by ROHM
© 2023 Device Plus. All Rights Reserved. Muffin group

istanbul escort istanbul escort istanbul escort