Skip to main content

Types Of Current Collector

Current Collector

A current collector is a device used to collect electrical current from a moving conductor, such as a train or a trolley. It is typically used in electric vehicles, such as trains and trams, to transfer power from an overhead power source to the vehicle's electric motor.

The current collector consists of a sliding contact, which is often made of carbon or copper, that makes contact with an overhead power source, such as an overhead catenary wire or a third rail. The sliding contact is mounted on the vehicle and is typically in the form of a pantograph or a trolley pole.

The pantograph is a device with a metal frame and a spring-loaded arm that presses against the overhead power source. It is raised and lowered by the operator of the vehicle, and as it moves along the overhead power source it maintains contact and collects the electrical current.

The trolley pole is a vertical pole that is mounted on the roof of the vehicle and has a horizontal arm that extends out from the pole and makes contact with the overhead power source. The pole is typically mounted on a swivel, which allows it to move as the vehicle turns.

The current collector is a critical component in the operation of electric vehicles, as it is responsible for collecting power from the overhead power source and transferring it to the vehicle's electric motor.

Types Of Current Collector

In order to collect the current sparkless, even pressure should be maintained against the trolley wire at all speeds. Three types of collectors are mainly used which are as follows.
  1. The trolley type
  2. The bow type
  3. The pantograph type

1. Trolley collector

A trolley collector is used on tramways and trolleybuses and mounted on the roof of the vehicle. Contact with the overhead wire is made by means of either a grooved wheel or a sliding shoe carried at the end of a light trolley pole attached to the top of the vehicle and Held in contact with the overhead wire by means of a spring. 

Trolley collectors always operate in a trailing position. It is employed up to speeds of about 32 km/h as beyond this speed there's every possibility of the wheel jumping off the trolley wire.

Trolley collector
The trolley collector is adopted on tramways and trolleybuses. Current is collected by means of a grooved wheel or a sliding shoe, supported at the end of a long trolley pole attached to the top of the car and held in contact with the wire by a spring. 

The pole is made to swivel about its support so that it can be reversed for reverse running and rendering it unnecessary for the trolley wire to be accurately maintained above the center of the track. 

It enables the bus to manage traffic up to a distance of 3.5 to 4.5m on either side of the contact wire. Although the wheel has a deep groove there is a danger of its jumping off the wire, at points and crossings, at speeds of more than 30 km/hr.

2. Bow collector

It can be employed for a higher speed. It consists of a light metal strip or bow (about 1m long) pressing against trolley wire and the framework is mounted on the roof of the car. 

The strip is made up of soft material (e.g. Copper, Aluminum, or Carbon). A bow collector also operates in a trailing position. Hence it requires the provision of either duplicate bows or an arrangement for reversing the bow for running in the reverse direction. 

It is not suitable for railway work where speeds up to 120 km/h and currents up to 3000A.
Bow collector
The current may be collected by means of a light metal strip of bow 0.5 or 1 meter wide, attached to a framework mounted on the roóf of the car. This type of collector is commonly used for tramways in Europe. It enables higher speeds to be run without the danger of jumping.

3. Pantograph collector

The Pantograph collector maintains the link between the overhead contact wire and the power circuit of the electric locomotive at different speeds under all wind conditions and the stiffness of overhead equipment. 

This necessity is that positive pressure must be maintained at the least time to avoid loss of contact ad sparking but the pressure must be as low as possible in order that the wear of the overhead contact wire is minimum. 

It is mounted on a pentagonal framework which may be raised or lowered by compressed gas or springs. Compressed air for raising is normally used. It is used where vehicles at high speeds i.e. in railways and where currents to be collected are large (2000 to 3000A).

Bow collector
For railway work for speeds up to 150km/h or 130 km/h and currents up to 3000 A and a light pantograph construction, as shown on the locomotive is used. The tubing of high-tensile alloy steel is generally employed to ensure lightness as well as adequate strength.

Popular posts from this blog

RS Aggarwal Aptitude Book PDF Free Download

RS Aggarwal Aptitude Book PDF Free Download RS Agarwal Aptitude Book PDF Free Download: Quantitative Aptitude by R.S Aggarwal is a standout amongst the most inclining books among the hopefuls getting ready for Bank PO, PO, MBA, RBI, IBPS, CAT, SSC, IAS, PSC, Hotel Management, Railway Recruitment Exams, and other aggressive and placement tests. This book is suggested by different specialists in this field. This book covers relatively every theme which is being requested for the focused exams. On the off chance that you are looking to Download RS Aggarwal Quantitative Aptitude PDF's most recent version with the expectation of complimentary then you appear to be at the correct place.    Download PDF  RS Agarwal Aptitude Book PDF Free Download This book covers Problems on Surds and Indices, Simplification, Numbers and Ages, Pipes and Cisterns, Boats and Streams, Problems on Trains, Simple and Compound Interests, Time and Work, Permutations and Combination, Clocks, Odd Man Out, Heights

Limitations of Terzaghi Theory

Limitations of Terzaghi Theory The value of the coefficient of consolidation has been assumed to be constant.  The distance d of the drainage path cannot be measured accurately in the field. The thickness of the deposit is generally variable, and an average value has to be estimated.  There is sometimes difficulty 1n locating the drainage face, and sometimes thin previous seams that can act as good drainage faces are missed in the boring operations. The equation is based on the assumption that the consolidation is one-dimensional. In the field, the consolidation is generally 3-dimensional. The lateral drainage may have a significant effect on the time rate of consolidation. The initial consolidation and secondary consolidation have been neglected. Sometimes these form an important part of the total consolidation. In actual practice, the pressure distribution may be far from linear or uniform.

Comparison between VSI and CSI

Comparison between VSI and CSI In power electronic systems, inverters are an essential component that converts direct current (DC) into alternating current (AC). There are two main types of inverters used in power electronic systems: Voltage Source Inverters (VSI) and Current Source Inverters (CSI). Both have their own unique advantages and disadvantages, and the choice of which to use depends on the specific application and the desired outcome. Comparisons between voltage source inverters and current source inverters are as follows. In voltage source inverters, the input voltage is maintained constant and the amplitude of the output voltage does not depend on the load. However, the waveform of load current, as well as its magnitude, depends upon the nature of load impedance.  In current source inverters (CSI), the input current is constant but adjustable. The amplitude of output current from CSI is freelance of the load. However, the magnitude of output voltage and its undulation outp