What is the application of dual converter?
Application of Dual Converter Direction and speed control of DC motors. Applicable wherever the reversible DC is required. Industrial variable speed DC drives.
What is the advantage of dual converter?
Explanation: Dual converters provide four quadrent operation, which means voltage can be positive or negative and so can be the current. Hence, AC-DC, DC-AC any converter configuration can be used.
What is dual converter controlled drive?
Dual converters are commonly used to operate the dc drives where the four-quadrant operation needed. Two back to back connected full controlled converters are called as dual converter. One of the converter works as a ac to dc converter and the other one works as a dc to ac converter.
What are the four quadrants of dual converters?
First quadrant: voltage and current both positive. Second quadrant: voltage is positive and current is negative. Third quadrant: voltage and current both negative. Fourth quadrant: voltage is negative and current is positive.
What is the difference between full converter and dual converter?
Full wave rectifiers have three configurations - fully controlled, semi controlled and uncontrolled. Fully controlled config has 4 SCRs, semi controlled config has 2 SCRs and 2 diodes and uncontrolled config has 4 diodes. SCRs make the control over the output voltage possible (by controlling the firing angle).
What causes circulating current in dual converter?
3. What causes circulating current in dual converters? Explanation: In case of practical dual converters, the voltages from both the converter circuits though equal in magnitude is out of phase. This indifference in voltages causes circulating currents to flow.
How many SCR is dual converter?
Single Phase to Single Phase Cycloconverters: This Cycloconverter has two full wave converters connected back to back. If one converter is operating the other one is disabled, no current passes through it. The Single Phase to Single Phase CCV has two pairs of full wave rectifier circuits, each consisting of four SCR.
What is single-phase full converter?
Single-Phase Full Converter: Single-Phase Full Converter converts the AC signal to DC signal and utilizes thyristor only. The utilization of thyristor only for the conversion process makes it fully controllable and provides wider control over the level of DC output voltage.
In which quadrant does dual converter operate?
Dual converters are used for the four-quadrant operation. It has two converters that are connected back to back. One of the bridges works as rectifier (AC to DC) and other bridge works as inverter (DC to AC)
What is 4 quadrant of DC motor?
Four Quadrant Operation of any drives or DC Motor means that the machine operates in four quadrants. They are Forward Braking, Forward motoring, Reverse motoring and Reverse braking.
What is the function of the inverter converter?
Converters and inverters are electrical devices that convert current. Converters convert the voltage of an electric device, usually alternating current (AC) to direct current (DC). On the other hand, inverters convert direct current (DC) to alternating current (AC).
What is buck converter and its working?
The buck converter is a ubiquitous DC-DC converter that efficiently converts a high voltage to a low voltage efficiently. Efficient power conversion extends battery life, reduces heat, and allows for smaller gadgets to be built. The buck converter can be used in lots of cool applications.
What are the disadvantages of dual converter?
The dual conversion uses two local oscillators in the circuit, the circuit can act as power hungry due to extra matching required. Hence, modern receivers tends to avoid this kind of structure for receivers.
What are the condition for ideal dual converter operation?
Ideal Dual Converter The firing angles must be properly controlled here so that the average output voltage of the two converters must have the same magnitude and polarity. To attain this condition, out of the two, one converter must act as a rectifier while another as inverter.
What is buck converter and its working?
The buck converter is a ubiquitous DC-DC converter that efficiently converts a high voltage to a low voltage efficiently. Efficient power conversion extends battery life, reduces heat, and allows for smaller gadgets to be built. The buck converter can be used in lots of cool applications.
In which quadrant does dual converter operate?
Dual converters are used for the four-quadrant operation. It has two converters that are connected back to back. One of the bridges works as rectifier (AC to DC) and other bridge works as inverter (DC to AC)
What is dual converter?
Dual converter, the name itself says two converters. It is really an electronic converter or circuit which comprises of two converters. One will perform as a rectifier and the other will perform as an inverter. Therefore, we can say that double processes will occur at a moment.
What are the two types of dual converters?
They are of two types: Single-phase dual converter and three-phase dual converter.
What is the firing angle of a converter 2?
During the converter 2 operation, firing angle (α 2) will be 0<α 2 < 90 o; V dc and I dc are negative.
How many converters can be used at a time?
One converter will perform at a time. So there is no circulating current between the converters.
What is ideal output voltage?
The term ‘ideal’ refers to the ripple free output voltage. For the purpose of unidirectional flow of DC current, two diodes (D 1 and D 2) are incorporated between the converters. However, the direction of current can be in any way. The average output voltage of the converter 1 is V 01 and converter 2 is V 02. To make the output voltage of the two converters in same polarity and magnitude, the firing angles of the thyristors have to be controlled.#N#Average output voltage of Single-phase converter =#N#Average output voltage of Three-phase converter =#N#For converter 1, the average output voltage,#N#For converter 2, the average output voltage,#N#Output voltage,#N#The firing angle can never be greater than 180 o. So,
What is dual conversion?
In a dual conversion system, the two converters out of which one acts as rectifier while another acts as inverter are connected to a common dc load. Thus is called so.
What is an ideal dual converter?
An ideal dual converter provides such an output voltage that is free from ripples. The figure below represents the circuit of an ideal dual converter:
How long does it take for a conduction converter to change to another?
It is to be noted here that at the time of changing the conduction from one converter to another the current through the load must be reduced to zero. A delay time of around 10 to 20 sec must be there between stopping the conduction of a converter and applying the firing pulse to another converter. With this time delay, the SCRs of the active converter will get properly commutated. However, if this time delay between switching of one converter to another is skipped then this will lead to cause flow of large circulating current between the two converters as both will be in the active state.
How many full converters are needed for a four quadrant load circuit?
Thus, in order to have a four-quadrant operation, we use two full converters in back-to-back orientation to the load circuit. This provides an antiparallel arrangement of two full converters that give rise to dual converters.
What is a half controlled converter?
All half-controlled converters offer single quadrant operation and help to convert ac power to dc power. In this case, the whole operation is restricted to the first quadrant, of the output current-voltage plane. While the fully controlled converters are the ones that generate direct output voltage where the current flows in one direction, operates in the first and fourth quadrant. Such converters are helpful in applications like dc torque motors.
What are the opposite polarities of the two output voltages?
In the normal operating condition, the two output voltages exhibit opposite polarities i.e., the two plates of converter 1 upper positive and lower negative while the two plates of converter 2 are exactly opposite. However, an assumption regarding average magnitude is made where the magnitude value is the same.
Do both converters conduct at the same time?
Here as both the converters conduct at the same time thus, the circuit requires a current limiting reactor in the connecting terminals of the two converters. Due to the simultaneous conduction mode of the converters, the firing angle must be so adjusted that a minimal circulating current must flow through the reactor. This mode of operation offers quite a fast time response.
What is a converter?
A converter changes a signal from one format to another and in our products you’ll find two kind of converters, an Analog to Digital Converter (ADC) and a Digital to Analog Converter (DAC).
How many times can a converter take samples?
Let us explain simply. Converters operate at high speeds, taking samples of the audio up to 96,000 times per second and with each sample being made up of up to 24 binary digits.
How much is the deviation of a signal?
The deviation value is expressed as a plus or minus decibel figure (+/- dB) across a given frequency range.
How does a first converter work?
Out of these two converters, the first converter works in two quadrants depending upon the value of firing angle α. This converter works as a rectifier when the value of α is less than 90˚. In this operation, the converter produces a positive average load voltage and load current, and operates in the first quadrant.
What type of converter is used for load?
According to the type of load, single-phase and three-phase dual converters are used.
What is the firing angle of a converter?
The firing angle of converter-1 is α1 and α1 is less than 90˚. Hence, the converter-1 act as a rectifier. For positive half cycle (0 < t < π), thyristor S1 and S2 will conduct and for a negative half cycle (π < t < 2π), thyristor S3 and S4 will conduct. In this operation, output voltage and current both are positive. So, this operation is known as forward motoring operation and the converter works in the first quadrant.
What happens when load current is reversed?
If the load current is reversed, the converter which is operated as a rectifier is now operating as an inverter, while the converter which is operated as an inverter is now operating as a rectifier. In this scheme, both converters conduct at the same time. So, it requires two firing angle generator unit.
What is a positive group converter?
The converter operating as a rectifier is called a positive group converter and the other converter working as an inverter is called a negative group converter.
How many three phase converters are connected back to back?
The circuit diagram of the three-phase dual converter is as shown in the below figure. Here, two three-phase converters are connected back to back. The principle of operation is the same as a single-phase dual converter.
How long is the delay time for converter 2?
The pulses to the converter-2 are applied after a delay time. The delay time is around 10 to 20 msec. Why we apply delay time between the change of operation? It ensures reliable operation of thyristors. If converter-2 trigger before the converter-1 has completely turned off, a large amount of circulating current will flow between converters.
What is a dual converter?
Dual converters are mainly found in variable speed drives V F D s. In a dual converter, two converters are linked together back to back. The operation of a dual converter is explained using the diagram below. It is assumed that −
Which diodes show unidirectional flow?
Diodes D1 and D2 show the unidirectional flow of current.
What is an inductive charger?
Inductive chargers − Uses electromagnetic induction to charge the battery. Intelligent chargers − Used to charge a battery that contains a chip that communicates with the smart charger. Motion powered charger − Makes use of human motion to charge a battery.
How does a simple charger work?
Simple chargers − Operates by supplying a constant DC power source into the battery being charged.
What are the different types of battery chargers?
Types of Battery Chargers 1 Simple chargers − Operates by supplying a constant DC power source into the battery being charged. 2 Fast chargers − Uses control circuitry to charger the battery rapidly and in the process prevent the battery cells from damage. 3 Inductive chargers − Uses electromagnetic induction to charge the battery. 4 Intelligent chargers − Used to charge a battery that contains a chip that communicates with the smart charger. 5 Motion powered charger − Makes use of human motion to charge a battery. A magnet placed between two springs is moved up and down by human motion thus charging the battery.
What is dual converter?
The dual converter is a power electronics control system to get either polarity DC from AC rectification by the forward converter and reverse converter. It can run a DC motors in either direction with speed control too.
How does a dual converter work?
One of the bridge works as a rectifier (converts AC to DC), another half bridge works as an inverter (converts DC to AC) and connected commonly to a DC load. Here two conversion processes take place simultaneously, so it is called as a dual converter. The dual converter can provide four quadrant operations. The four quadrant operation is shown below.
How does a single phase converter work?
This single phase converter is achieved by using a pair of a thyristor controlled bridge (4 SCRs X 2) that enables the DC motor to get reversed polarity for either direction rotation and speed control also lowered in steps by Microcontroller triggering each bridge SCR bank of duly interfaced through Opto-isolators.
What is converter 1?
The Converter 1 consists of Rectifier. Then the rectified DC fed to a filter which removes pulses from rectified DC and converts it to a pure DC by filtering.
What is the diode D1 and D2?
Here Diode D1 and D2 represent the unidirectional current flow characteristics of the converters. However, the direction of current can be in any way. Let us assume, the average output voltage of the converter 1 is V01 and converter 2 is V02. To make the output voltage of the two converters in same polarity and magnitude, the firing angles of the thyristors have to be controlled.
What is a three phase dual converter?
In three phase dual converter, we make use of three phase rectifier which converts 3 phase AC supply to DC. The structure of the converter is same as single phase dual converter.
What voltage motor is used for polarity reverse?
This project uses 12-volt ac at the input and a 12 volt DC motor to verify either direction rotation as the polarity gets reversed.
