FIELD OF THE INVENTION
The present invention relates to an Embedded Contactor Controller for DC Drive
of Rapid transport System.
BACKGROUND OF THE INVENTION
Servo motor driven Cam Shaft Controller (CSC) is used in existing Metro trains
for resistance switching of the Power Circuit. Combination of Power Switches and
Auxiliary switches is operated by the Cams mounted on the shaft. The rotation of
the shaft is controlled by the Servo motor and a gear box assembly. However,
failures in the CSC are increasing, because positioning of the contacts is based
on a gearing mechanism which is susceptible to misalignment and failure.
Embedded Contactor Controller for DC drive will provide an alternate to CSC
resulting in improved performance of propulsion system, as this embedded
controller is free of gear box and shaft arrangement and do the resistance
switching directly by opening and closing the contacts which in turn is controlled
through embedded software.
OBJECTS OF THE INVENTION
It is therefore an object of the present invention to propose an Embedded
Contactor Controller for DC Drive of Metro System to replace the existing Cam
Shaft Controller for eliminating the prior art problems.
Another object of the present invention is to propose an Embedded Contactor
Controller for DC Drive of Metro System, which is capable for both make and
brake operation of power contactors.

A still another object of the present invention is to propose an Embedded
Contactor Controller for DC Drive of Metro System which provides faster
resistance switching of the Power circuit.
SUMMARY OF THE INVENTION
Accordingly, there is provided an embedded contactor controller for DC drive of a
rapid transport system to provide fast-switching of the power circuit of the DC
drive and operate the power contactors of the circuit under make or break
sequences, comprising : a processor having a software structure to evaluate the
plurality of input and output data, transmit command to the power contactors for
sequential resistance switching, and controlling operating parameters of
acceleration, jerk rate, and speed of the system; an input device for feeding on-
line data; peripherial electronic modules consisting one of electronic circuit,
application-specific integrated circuit, a software or a firmwire with processor for
acquiring and transmitting on-line data to the main processor; an output device
for display of processed data to allow control of the physical components of the
D.C drive system; a logic circuit; and a memory device for storage of data.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figure 1 shows a Block diagram of a DC Drive Metro System with Servomotor
driven Cam Shaft Controller of prior art.
Figure 2 shows a Block diagram of Embedded Contactor Controller for DC Drive
of Metro System with Contactor Box according to the invention.

DETAILED DESCRIPTION OF INVENTION
Embedded Contactor Controller for DC Drive of Metro System according to the
invention, is enabled to control the power contactors directly through their
Electro magnetic operating coils. To take care of the inductive nature of the coil
load, a plurality of fast acting intermediate relays are used. Due to direct control,
the response of the system is very fast and the system can be configured as per
the requirement of different train applications by changing and tuning the
software only. This will enable the system to be suitable for new and retrofitment
jobs.
Embedded Contactor Controller for DC Drive of Metro System comprises a
processor and other peripheral electronic modules for processing, and means for
data input and output. The outputs of various contactors are fed to the controller
for processing and taking decision. The software program evaluates the logic and
command the Contactors for sequential resistance switching and controlling the
acceleration, jerk rate, and speed of the train. This will also store the faults for
transmitting the same through communication port as required for Train
Information Management System and Display system.

ADVANTAGES OF THE INVENTION
Advantages of the invention over the prior art, is depicted in a comparison table,
shown as under.


WE CLAIM :
1. An embedded contactor controller for DC drive of a rapid transport system
to provide fast-switching of the power circuit of the DC drive and operate
the power contactors of the circuit under make or break sequences,
comprising :
a processor having a software structure to evaluate the plurality of
input and output data, transmit command to the power contactors for
sequential resistance switching, and controlling operating parameters
of acceleration, jerk rate, and speed of the system;
an input device for feeding on-line data;
peripherial electronic modules consisting one of electronic circuit,
application-specific integrated circuit, a software or a firmwire with
processor for acquiring and transmitting on-line data to the main
processor;
an output device for display of processed data to allow control of the
physical components of the D.C drive system;
a logic circuit; and
a memory device for storage of data.