Majidreza Salehi

10 Questions 17 Answers 0 Followers

Questions related from Majidreza Salehi

Do you have any idea about DC current circulating in the primary side of a transformer based inverter?

I have a voltage source inverter connecting to a symmetrical load through a delta-star transformer. Surprisingly, the primary currents of transformer have DC components. the output voltage of...

01 August 2016 1,813 13 View

How should we choose the value of capacitor and inductor (LC filter parameters) of a stand-alone inverter? for example a 4 KVA or 40 KVA inverter?

I've seen a wide range of L and C values for LC filters for off-grid inverters in papers. Is it true to say that less inductance and larger capacitance must be chosen for high power inverters?...

17 March 2016 3,734 3 View

What special consideration should we give to choose a transformer for an inverter?

which kind of core material, wiring (delat-wye, delta-zigzag, ...) is appropriate for a 3-phase inveter according to the harmonic problems, acoustic noise, neutral overload supplying nonlinear...

28 January 2016 5,276 8 View

How can I Calculation of Dimension fin and tube for air conduction?

according to formula of Q=AU delta T , How can I calculate parameter A of coil condenser or evaporator of cooler?

18 January 2016 3,213 3 View

What is the optimum size of capillary tube in an air conditioner with 500w cooling capacity?

Manufacturers use capillary tubes for upper cooling by changing the diameter and length of the capillary tube. But I don't know the good diameter and length of the capillary tube for an air...

01 November 2014 3,590 5 View

What is the effect of the volume flow rate of a fan with evaporator and condenser coil dimension in air conditioner with cooling capacity 500 W?

I know in HVAC for example a condenser coil 1 cubic foot almost is suitable for 1 hp(horsepower)cooling capacity. But I don't know the relationship between evaporator and condenser size with...

01 November 2014 9,393 1 View

What is the reason of DC harmonics in grid-connected converters?

We designed a grid-connected converter for wind. We saw in the grid side there is a DC current. Can anybody solve this problem?

29 October 2014 5,496 10 View

What is the best method for detecting Sensorless Rotor Position in BLDC motor?

We have a small BLDC motor(160W) and the load of the motor is constant. I want to control the speed of the rotor. We don't have access to the rotor, so we should use sensorless method, but we have...

27 October 2014 4,167 3 View

Can anyone suggest a method for linear NTC for temperature measurement?

NTC is nonlinear.

11 October 2014 8,235 6 View

How can I detect islanding in a grid-connected converter?

The study and development of anti-islanding controls are very important in wind and solar applications.

11 October 2014 4,556 10 View