An electrical actuator converting electrical energy into rotational motion.

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5
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2answers
244 views

Voltage spikes when driving DC motor with N-channel MOSFET

I'm trying to drive a DC motor (12V, 100W) with MOSFET IRFP054N. PWM frequency is 25 kHz. Here's the schematic: I know DSEI120-12A is not the best diode for this but I don't have any better right ...
6
votes
2answers
411 views

Why do we need a ramp for stepper motor?

I am a newbie and trying to understand how i can run a stepper motor. The concept i had in mind was that steppers need digital pulses to run, and i tried it out too. I was able to run the stepper i am ...
0
votes
0answers
97 views

Selecting motor for a DIY wheelchair stairlift

I need to make an wheelchair stairlifter for my stroked mother similar to : So I need to find out one motor in range of 200 Wat for lifting a 200KG load in slope of 43 degree from these options: ...
-1
votes
3answers
131 views

Mosfet time and PWM frequency relation

what is the relation that I have to take into account when I select a mosfet(or a transistor in general) for pwm driving about rise/fall/turn off delay/turn on delay and the PWM frequency? How to ...
0
votes
2answers
71 views

How to transfer electrical power from stationary to rotational part.that can be used for POV display?

I have been researching how to transfer electrical power from stationary to rotational part. Some of them showed the means by using slip spring rings like in this website ...
0
votes
1answer
58 views

Why does the current in autotransformer motor starting gets reduced squared in relative to the voltage?

Say, relatively, the motor's full voltage rating's voltage, current and torque are 100, 100 and 100 Why does when the autotransformer tap is set at 80%, the motor runs at 80 64 64 65% and 50% as ...
1
vote
2answers
64 views

Minimum current to measure from a 30kW motor?

We've been troubleshooting a problem here at work and we're kinda stuck so I thought about asking for some opinion from you guys. We have a 30kW 240V 3-phase motor with a rated current of 109A that is ...
0
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0answers
45 views

Control multiple high current channels in mass production

We have to controll 4-6 channels with high current (3-5A ) ,with a micro controller, with control voltage of about 3v . One ...
0
votes
1answer
91 views

Driving a 4.5V motor with PWM from an Arduino

This is a basic question but I would appreciate help. I have: An Arduino A 4.5V DC motor Various transistors, like BC337, 2N7000, 2N2222A What I'm trying to do is very simple: control the motor ...
0
votes
3answers
85 views

Transistor with different voltage in colector and base

I have a small LED of 5mm and an arduino powered by 9V. When I connect the LED to Vin (9V) using a 330 ohm resistor the LED brights very high. When I connect the LED to 5V (from arduino) using a 330 ...
0
votes
3answers
69 views

Using a motor with DC

I am using a Lego DC motor with a 9V battery which can provide up to 1A of current. I called Lego support and they said the motor draws 300mA of current. What does that mean? If I plug the motor to ...
1
vote
1answer
151 views

“Standard orientation” for stepper motors in data sheets

I just finished getting a SOYO 6V@0.8A unipolar stepper motor working, and wanted to know more about an issue I faced while doing so. I used the stepping sequence below with an L293D chip to drive ...
2
votes
3answers
112 views

Can a DC motor be of specification 320Watts, 3A, 24 V?

The above is the specifications of a wheelchair DC motor I'm trying to use as my hobby project. My question is how can a motor of 320 Watt and ...
1
vote
2answers
226 views

Is my MOSFET H-bridge design correct?

Can anyone check over this motor controller design I made? I'm running off of a rudimentary understanding of electronics (just a hobbyist), so I'm not fully confident in it yet. Kamil EDIT: ...
0
votes
0answers
134 views

Can I run a 3s ESC from a 12V power supply (car battery)?

I am building an ROV, and my thrusters will require 12V. The voltage source will be a 12V car battery. I have found this ESC and it seems to be just what I need (well over my ~9A draw and has ...
0
votes
1answer
95 views

Mechanical Power (Application) and Electrical Power (Stepper Motor) Discrepancy

For my application I need a torque of \$\tau=0.87 \, Nm \$ and a speed of \$ w=140 \, RPM \approx 14.65 \, rad/s \$. This gives me a mechanical power \$ P_m=12.75 \, W\$. $$ P_m=\tau w $$ I have ...
0
votes
2answers
290 views

Can I solder back together a single broken copper winding wire in an electric washing machine motor? [closed]

Can I solder back together a single broken copper winding wire in an electric washing machine motor? This is the motor: ...
1
vote
1answer
59 views

Spice simulation of a motor switching power supply

I'm designing a switching regulator for motor controlling, I have tried this circuit with spice but it does not work: The problem is that the voltage on the load of the regulator never goes down, ...
0
votes
0answers
421 views

Making a simple wireless remote control circuit to control a micro motor

All I need is to be able to activate a small 4mm by 6mm micro motor with a remote wireless switch. Just on and off. I have searched everywhere for help and I can't figure anything out, I am ...
0
votes
1answer
71 views

DC Motor Coil Voltage

I have a DC stepper motor that appears to be powered by 75V supply voltage (I measured this). However after connecting the motor to the controller (supply), I measured the voltage across the coil ...
5
votes
3answers
228 views

How to tackle regenerative current in my H-bridge

I am using 2 of the following H-Bridge to control 2 x 24V 350W electric scooter DC motors. The power is from 2 x 12V 12AH SLA batteries in series. EDIT: These are the entire schematic and PCB ...
0
votes
0answers
41 views

What factors affect the choice of a particular variant of the Clarke transformation?

I have a question about the different variants of Clarke transformation. In one of the responses on this site, I read the following: 3->2 symmetric component transforms (a.k.a. "Clarke") are not ...
1
vote
1answer
100 views

Need help isolating source of interference

I'm pretty new to electronics, but have been successfully working with a Spark Core (www.spark.io) and some simple drivers/circuits for now. That said, I've run into a problem. I have a Spark Core ...
1
vote
0answers
52 views

How much has the power density of electrical motors and generators changed in recent decades?

I would like to know how much lighter (if at all) a matched combination of an electrical motor and generator with a given power output would be today, compared to a similarly powerful combination ...
0
votes
0answers
48 views

Computer Controling The Mouse Of Another Computer Issue

I am a nooby to electronics but I have a decent background in Programming. I have a project I am trying to do which is to make computer1 control the mouse of computer2. Basically, I want to use motors ...
0
votes
0answers
65 views

Stepper motor with integrated circuits and encoder controlled by custom software

I am new to electronics but I have decent experience in programming. What I would like to do is have 2 stepper motors attached to my computer, and then develop a program that would control their ...
0
votes
0answers
160 views

Using two half bridge drivers as a full H bridge - What bootstrap capacitor?

I'm trying to design a motor (brushed DC) speed controller circuit (to learn about such circuits). I decided to use two half bridge drivers (IR2184) to control my bridge. The circuit I've come up ...
0
votes
2answers
250 views

Why do AC motors have various back EMF shapes?

I just saw in one of the threads that apparently, a permanent magnet synchronous motor and a brushless DC motor have different back EMF shapes. But why? I thought those two were exactly the same in ...
0
votes
1answer
93 views

DC motors, AC motors, and Kv

As I understand it, DC motors have Kv values because their speed is determined by the applied voltage. AC motors don't have Kv values because their speed is determined by the frequency of the AC ...
0
votes
1answer
109 views

Will a flyback diode prevent an analog MCU input from being destroyed in this schematic?

Quick question: In this schematic, would D1 prevent high flyback voltages caused by the motor going into the voltage divider network and destroying pin A0 on the MCU? Pin A0 can only tolerate 5V max. ...
0
votes
2answers
102 views

What factors can determine the constant coefficient when calculating torque?

In this servo motor's datasheet, both motor have the same torque of 0.32 Nm, have the same power of 100w, but have different rated currents and voltages. It seems that the "torque" relates to the ...
0
votes
1answer
99 views

Current usage with multiple PWM controlled motors

I have a circuit that can use 25 A of current max, it is on a 25 A fuse. I am looking to control 4 DC brushless motors using ESC's. The trouble is that the motors are rated at 7A max current. I know ...
0
votes
2answers
120 views

Will these heatsinks be sufficient for my mosfets?

I need to control 10 12VDC motors at ~25Amps, so I decided to make my own mosfet H bridges to control it ( with 2 n chan et 2 p chan ). I will need 10 H-Bridge, so 40 Mosfets. ( 20 n chan and 20 p ...
1
vote
3answers
109 views

HEXFET PWM motor driver does not work

I'm trying to drive a motor for an academic project, using the circuit in the image. The STM32F4 Discovery board that I'm using in this phase of the project produces a 30Khz PWM at 3V, that is correct ...
0
votes
0answers
130 views

PWM and brushed DC motor - AC input? Limiting RPM?

I'm looking to replace the 20-year old poorly-performing speed control in a MIG welder. It allows the user to adjust the speed of a small brushed DC motor, which drives thin welding wire of of a ...
0
votes
1answer
54 views

Voltage wave form across a DC motor driven by a transistor with pwm

Above is the simple implementation for a DC motor control with pwm. I was expecting to see a square wave with a Vmax when Q1 is ON and zero when Q1 is OFF like the one here: standard pwm But ...
0
votes
2answers
125 views

How to run a 6v 4amp motor at slower speeds for long periods of time (2 hrs)?

I am trying to get a project done for Halloween. I am running a 6V 4A motor (from a powerwheels) but need it to run slower. I tried using an adjustable charger and ran it at 3V to slow down the ...
0
votes
1answer
73 views

How does this motor drive circuit work?

The Drive terminals are connected to a PWM signal generated by an arduino micro controller. The purpose of this circuit is to isolate the arduino from the motors to avoid too much current being drawn. ...
0
votes
1answer
41 views

Motor control solution on the truntable for computer vision and optics usage

I'm lack of electrical engineering knowledge, I'm just a software engineer, so I need your help on the turntable design and control problem. I need a very accurate turntable to allow me to scan some ...
2
votes
2answers
297 views

Operation of a Growler to test armature shorts

Can someone explain to me how a Growler for testing electric motor armatures works please? I have obviously read the Wikipedia Growler page but it is still foggy. So the growler unit acts as the ...
0
votes
1answer
269 views

High Torque Brushless DC Motors in Small Package

I have a particular set of requirements that call for a relatively high stall torque for the space available (300 ozf-in for < 8cm length of motor). The motor would be operating at a relatively low ...
0
votes
1answer
239 views

Calculation of base current resistor resistance for a transistor operating in switch mode? [duplicate]

I have a 9V DC motor and I want to control its speed with an Arduino board with help of a power transistor TIP120. In one of the web-tutorials the writer explains how to calculate the resistor ...
0
votes
1answer
87 views

How to limit motor stall current?

I've run into a dilemma. I have two motors, both with a 2.2A stall current. I know that at start up, motors will draw their stall current because they are essentially stalled. However, my motor driver ...
0
votes
1answer
100 views

What is sine wave torque constant and voltage constant for electric motors

I am wondering if anyone can explain to me what the sine wave torque constants and the voltage constants are and how to calculate them for a specific electric motor? Thanks!
10
votes
3answers
602 views

Locking up a DC motor with constant supply a bad thing?

I am working on a little pen plotter project and for one of my motors (which supports the pen) I have used a small DC motor obtained from an old DVD drive. I have noticed that if I supply a constant ...
9
votes
1answer
202 views

Very intermittent power MOSFET failure

I am working on a very spotty motor failure (I am not the designer). We have a wound armature which is switched by power MOSFETs. These are driven by a FET totem pole type FET driver. When the ...
1
vote
0answers
78 views

No output at H bridge during quick power drop

I used a H bridge with PMW control to drive DC motor in two directions. I observed a strange phenomenon that during quick voltage drop, the PWM output at M2 is cutoff, although the T4 gate PWM input ...
5
votes
5answers
324 views

Can a motor's movement be improved to any arbitrary resolution?

For a project that I'm working on, I need motor rotation at extremely small increments -- my desired resolution is about ~0.15 degrees per minimum rotation step. Of course, most motors of reasonably ...
1
vote
1answer
122 views

Powering a large DC motor from the mains

I scavenged a 220 volts DC motor from a large photocopy machine. How can I best get a suitable 220 volts DC supply when our local main supply is 240 volts AC? Since the voltages are so close is ...
1
vote
1answer
199 views

Are these H-Bridge circuits set up correctly?

I know I can use a driver chip to simplify this a lot, but I just want to make sure that I have the concept of H-Bridges down. Here they are: I have two motors, and each have 4 N-MOSFETs ...