What is meant by phase control?

[′fāz kən‚trōl] (electronics) A control that changes the phase angle at which the alternating-current line voltage fires a thyratron, ignitron, or other controllable gas tube. Also known as phase-shift control.

What is three phase controlled rectifier?

Three phase converters are 3-phase controlled rectifiers which are used to convert ac input power supply into dc output power across the load. Operate from 3 phase ac supply voltage. They provide higher dc output voltage and higher dc output power. Higher output voltage ripple frequency.

What is SCR application?

Applications. SCRs are mainly used in devices where the control of high power, possibly coupled with high voltage, is demanded. Their operation makes them suitable for use in medium- to high-voltage AC power control applications, such as lamp dimming, power regulators and motor control.

What is the use of controlled rectifiers?

A fully controlled or half-controlled rectifier is used to generate the dc voltage for the inverter. In addition, the input rectifier acts as a battery charger. The output of the inverter is filtered before it is fed to the load.

What is meant by phase control DC regulator?

Single Phase AC Voltage Controller is a device which converts fixed single phase alternating voltage directly to a variable alternating voltage without a change in frequency. The input and output of the device is single phase.

What is phase controlled thyristor?

Thyristors are typically used as phase-controlled current valves for AC to DC conversion and vice versa, operating at low frequencies (most often around AC line frequency).

What is difference between controlled and uncontrolled rectifier?

Uncontrolled Rectifiers : Provide a fixed d.c. output voltage for a given a.c. supply where diodes are used only. Controlled Rectifiers : Provide an adjustable d.c. output voltage by controlling the phase at which the devices are turned on, where thyristors and diodes are used.

What are the advantages of three-phase controlled rectifier?

Advantages of three-phase rectifier over a single-phase rectifier: The transformer utilization factor is high. More efficient than a single-phase system. The power output and therefore rectification efficiency are quite high.

Why SCR is called controlled rectifier?

But, the silicon controlled rectifiers doesn’t conduct even though the anode voltage is greater than the cathode voltage unless until the (third terminal) gate terminal is triggered. Hence, the thyristor is also called as controlled rectifier or silicon controlled rectifier.

What is called controlled rectifier?

The diodes are termed as uncontrolled rectifiers as they conduct (during forward bias condition without any control) whenever the anode voltage of the diode is greater than cathode voltage. Hence, the thyristor is also called as controlled rectifier or silicon controlled rectifier.

What is working principle of phase control technique?

4.1 PHASE CONTROL TECHNIQUE The thyristor switch is turned on for a part of every half cycle, so that input supply voltage appears across the load and then turned off during the remaining part of input half cycle to disconnect the ac supply from the load.