Many thanks for your reply. Can you give me more details what do you mean by operator issues? Are the same operator issues not exist in electric arc furnace. Also, what are the critical sizes in tons to choose either induction furnace or electric arc?
We use scrap to create steel.
I found this article about china banned induction furnaces. Are induction furnace creates low quality steel and has risk on workers...
Dear All,
I would be grateful if you can help me. Our steel company want to buy a furnace with 25 ton capacity for continuous casting process. We are confused with type of furnace we should select (Induction or arc electrical furnace). I read alot of information on internet and I am still...
I don't have circuit diagram and I need to design a circuit for hydraulic fatigue machine. I am wondering where can I find help and guide in designing such hydraulic system. I saw a photo for fatigue machine and I found they use 2 accumulators.
@Brian. Yes, there are dynamic loads during the...
Actually, it was for hydraulic fatigue testing machine. The two accumulators were connected to the cylinder which was controlling the force and the load. The load varies during the testing cycle in cyclic load .
Dear All,
I have a question and I would be grateful if you can help me to find its answer. I saw in some hydraulic circuits they use 2 accumulators for both high and lower pressure. I don't understand why they use two. I would be grateful if you help
Dear All,
I am confused in the calculation the frequency response (amplitude ratio and phase shift). What is the frequency units? Is it rad/sec or hertz?
I have Ogata, but I can't find these information
If there is a double integration in the plant under control -- for instance, from a torque/force command thru velocity to position -- you need derivative action to get the damping required for stability. Proportional gain here is just a spring...
Many thanks Curt. You provided me with very useful information. where can I read more about these about these recommendations for PT, PID and PD.
Regards,
Dear all,
I have a question regarding using PI or PD control based on the control variable. Is there a relation? As I found a lot of people use PI controller for speed or current control for servo systems. However, PD is used a lot for position or force control. I am wondering if there are...
Hello,
I have torque sensor based on strain gauges. I use it to measure the torque directly. I have a robot and I want to do torque control on its joints
Dear All,
I am wondering if it okay to have cascaded torque and current control loops to control the torque of a system driven by DC motor. The torque control will be the outer loop and has the set torque value and the current is the inner control loop on the DC motor. Is that okay? or it is...
Dear All,
I am looking to do PID torque control on a mechanical system derived by DC motor. The system has torque sensor to measure the actual torque on the system and the motor is derived by PWM motor driver. The PWM motor driver can work in either voltage control or current control. The input...
Dear All,
I have a question related to using power screw. Power screw is used to convert torque into axial forces on the nut. The axial forces between the nut and power screw will be equal and opposite to each other and the applied torque on the screw is function in applied forces. My question...
Hi
I have a question related to PWM vs. Linear Amplifier. I know the PWM amplifiers run cooler than standard linear power amplifiers and hence the PWM amplifiers has higher efficiency. I am wondering what about the motor itself. Are both PWM vs. Linear Amplifier produces the same heat losses on...
Many thanks to you all.
@ dogzzz . Do you mean measuring the voltage across the power supply, but the power supply voltage is constant and known? I am wondering if I can measure the effective voltage applied to the brushless DC motor as I don't know any information about the driver efficiency
Many thanks electricpete for detailed elaboration
So this means if I used low pass filter connected in parallel with the motor terminals I can measure the effective voltage as the low pass filter will provide the average value. Also, the current I0 is the average value too. Many thanks electricpete
Actually, I am little bit confused. As I want to measure the electrical power of a DC motor which equal to effective voltage*current. This motor is controlled by PWM motor driver. I was looking online and found some suggest that the effective voltage is the average voltage while the others...
