Modern Technique

Modern Technique

For the Railway Infrastructure Equipment

CNCF "CFR" SA strategy includes several projects referring to the development and the modernization of the railway infrastructure from Romania complying with the European standards, in order to provide its compatibility and interoperability with the European railway transport system.

Safety Traffic Equipment Sphere

In the field of safety traffic equipment - signaling, centralization and blocking (SCB) -, the development of CNCF "CFR" SA policy aimed at replacing the current relay signaling equipment with electronic signaling equipment, based on IT application, and at modernizing the power supply system of the equipment, through the implementation of some new types of inverters, rectifier equipment and accumulators, which, through ulterior developments, allow, to the switch electro-mechanisms, the operation through the agency of the electrical engines of three-phased alternative power. The railway infrastructure company currently exploits an electronic centralized equipment (CE) with 95 switches, 650 electrodynamics centralized equipment (CED) with 18,444 switch electro-mechanisms and clogs, 219 automatic barrier equipment with half-barriers (BAT), 859 automatic signaling equipment of the trains at level crossing without barriers (SAT), interlocking systems (BLA) for double track, introduces on 3,294 km, BLA equipment for the simple track, introduced on 1,912 km, and 19 automated marshaling yards with 100 track brakes. All these equipment manage 33,018 light signals, take over the information regarding the position of the rolling stock from 18,144 electrified track circuits, 8,551 track circuit at non-electrified tracks and controls the speed of the trains with punctual self-stopping equipment assembled on 10,296 km, through the agency of 27,880 track inductors.
The uninterrupted operation of this assembly imposes the existence of a safety power supply - which at CFR SA is compound of its own power networks of 220V/75 Hz - achieved with almost 1,300 rectifying equipment/accumulator/static inverters assemblies, with galvanic insulated outlets in comparison with the power networks and the ground.
The great majority of the rectifying /inverting assemblies are from the technical generation of the '65s, being characterized through small efficiency (almost 0.7) a high cooper, iron and aluminum consumption, the reduced possibilities for adjustment and protection at electric overloads or short-circuits high noise during the operation due to the vibration in 50 Hz and 75 Hz, automated schemas achieved with relays and contactors. The large duration of their uninterrupted operation, much more over the normal use duration (20 years), the high degree of aging of the insulation and the reduction of their reliability, the low protection at the accidental short-circuits on the charge, all these impose the transition to a new generation of power supply equipment, the achievement at parameters and the technology of the beginning of the third millenium.
Once with the inception of the rehabilitation program for the Corridors IV and IX, which, together have a fifth part from the entire length of the network, where there is unfolded almost half of the total traffic, the specialists of the company have analyzed from the technical and economical point of view the current achievements of the electro-techniques/electronics industry in the field, and has accepted the implementation, after a thorough and long experimenting in Craiova station, of the rectifier equipment and inverters achieved by INDA -SRL Craiova Company.
The orientation of the company to a Romanian company is included in the program for the re-launching of the national industry activity and for the maintenance of the places of work for the employees.

Romanian Peak Technique

INDA - SRL Craiova has been set up in year 1991, pursuant to the initiative to associate of some engineers specialized in the field of power operations and of the power electronics, for the achievement of certain peak technological products in the field of industrial automation. Its own research and production activity is oriented to the power operations, using the power electronics, to the power electronic equipment, yet to the special computers for electrical hauling or special computers for automation in industrial use, with dedicated operation, achieved with micro-controls.
The competitiveness of the company, attested as the railway supplier by AFER Bucharest, is based on the competence and the professionalism of its specialists, on their permanent information in order to be up to date for the adoption of certain modern conceptions, as well as on the use of the most performant electronic components in the world, purchased from abroad.
With an advanced managerial conception, INDA - SRL Craiova Company grants a great importance to the demands of the potential clients, from the country or from abroad. The team of the company proves its flexibility and promptness in solving the problems of its beneficiaries, and the defining believe of the company is not to accept the compromises between the costs and the performances of the achieved components. Through the capacity of the company to agree the technical motivations with the economical ones, in the context of selecting the most appropriate sub-assemblies or components from abroad (detecting elements, force transistors, micro-controls etc.) adequate technical conditions and the level of financing available in each case, there have been achieved many things, which have offered satisfaction to the specialists of the company, as well as to its beneficiaries.
The following equipment for the infrastructure of CFR SA are also included in the fabrication list:
╖ Three-phased rectifier equipment DCS type for the power supply of CED and BLA equipment;
╖ Mono-phased rectifier equipment DCS type for power supply of CED and BLA equipment;
╖ Mono-phased rectifier equipment RLC type for power supply of CED and BLA equipment from the contact line;
╖ True sinus inverters with fast commuting - ICR type for the supply of the track circuits with a voltage of 220V/ 75 Hz in CED stations and on BLA equipment;
╖ The three-phased frequency converter and the voltage of ISTA type for the operation of the switch mechanism with the asynchronous engine from CED stations.
All these equipment have technical parameters keeping up with the last hour evolution on the power components market from abroad and, there are also executed in order to provide the quality at ISO 9001.
INDA - SRL has introduced in fabrication - at all its equipment - the digital order, with micro-controllers and digital processors of specialized signal, supplied by big companies, as well as PHILIPS, TEXAS or SIEMENS, this way being also increased the operation possibilities, the precision and flexibility of the adjustments.
In the fabrication list there are also listed the following equipment meant to the electric hauling for the railway companies, the underground or the autonomous companies for public transport:

a) for the electric locomotives:
- static converter modules of CSA type for the operation of the compressor;
- the protection, signaling and diagnosis equipment of EPS type;
- board computers EPS/P/SA type;
- voltage static completes of converters and frequency 4 x CSA for the supply of the auxiliary services;
- SAGMA equipment for the operation of the LE 5,100 kW graduator with asynchronous engines;

b) for Diesel -electric locomotives:
- board computers of EPSAI type;
- HI inverters for the electric heating of the hauled train of LDE 2,100 HP (endowed with General Motors engine);
- CH-HI type converters for the electric heating of a hauled train of LDE 2,100 HP (endowed with classical engine);

c) for the underground train sets:
- static sources of MAS type for the supply of the auxiliary services.

For the entire country, INDA - SRL represents a special example of company, which, during the transition from the centralized, staged industry to the automatic, private one, has proposed, as a research and integrated production unit, to approach certain difficult segments - as the electronic equipment and the computers with dedicated operation-, but indispensable in their way for the modernization, automation and computerization of the railway transports, meeting the requirements of the clients, which become less and less dependent of the limitations characteristic to the imported solutions.

INDA Equipment for the Railway Infrastructure

All the equipment supplied to the Railways are achieved in metallic boxes protected against corrosion and stipulated with a earthed terminal. From the constructive point of view, the boxes have visiting doors with locking devices. The electronic side is based on modules which contain transistors with insulated gate - IGBT - of power and high frequency, and through the control strategy applied - the modulation in width at impulse (PWM), there has been reached to a solution for fast commutation (CR) at 16 Hz, which, by an appropriate filtering provides the stability of the necessary shapes at the outlets, the constancy of the adjustments reported to the size of the charge (from empty to the maximum) or its feature, insensitiveness at a high variation of the shapes at the outlets and the protection at the short-circuit on charge. The operation at 16 kHz has allowed the reduction of the filter dimensions, of the gauge and of the weight of the modules and the total elimination of the noise produced during the operation, creating a non-stressing work atmosphere for the maintenance persons.
Taking advantage of the control by microprocessor, all the subassemblies have an alphanumeric diagnosis panel and have digital display for the power supply parameters. The command clock, integrally electronically achieved, supply the necessary signals for various signaling, and by free potential contact of certain intermediary relays are supplied the necessary information for the remote -signaling regarding the operation or the disabled state.
Being assembled in the microclimate area with temperate climate (N), according to STAS 6535 - 83, they operate without forced ventilation, at atmosphere temperature included between 0o and 40o C.

The inverter with fast commuting ICR 5000 type

It has the role to supply the sinusoidal voltage of 220V/75 Hz for the supply of the track circuits existing in CFR stations and on railway tracks endowed with BLA.
Its main technical features are:
╖ supply voltage: 178 V cc +/- 20%;
╖ outlet voltage: 220 Vca +/- 3%;
╖ power: 5,000 VA (cos ЕЕЕ..included between 0.3 and 1);
╖ the frequency of the outlet voltage: 75 Hz +/- 0.5%;
╖ supplementary protection at the electric overload (including the short-circuit);
╖ efficiency (at 100% charge): better than 75%;
╖ harmonic distortions: less than 3%;
╖ automatic disconnection at the outlet from the voltage range allowed by the supply;
╖ high reliability during the operation;
╖ the average time of well operation (MTBF) is estimated at over 30,000 hours.
These inverters are designed to allow the operation in dependence with one or several inverters, by choosing the operation regime (STAND BY or INVERTER), the commutation time on the operational inverter on the spare one being smaller than 2 ms (the charge transfer on a source on another one is practically performed without any brake).
In Fig. 1 is presented a registration of the voltage on the charge when the first inverter is turned off.
The introduction of certain power detecting elements of high quality and of its own procedure of electric overload protection at the outlet (including the brutal short-circuit on the distribution bars) allows the operation of the IGBT transistors in a regime of providing the internal protection with non-destructive limitation. When a short-circuit is produced, protected by a fusible fuse, the inverters are able to supply the necessary energy in order to melt the fusibility in a very short time, and later on (after turning off the electric arch from the inside of the fuse), in a few milliseconds, the voltage at the outlet is automatically reestablished, without being necessary the intervention of the maintenance personnel.
In Fig. 2 is presented a registration of the voltage on the terminal of an inverter, when a short-circuit is produced on one charge, protected by a fusible fuse, which, by bringing the voltage at zero, has disturbed the operation for almost 55 milliseconds.

Three-phased rectifier equipment DCS 40A/178 V type

This is meant to operate as a main continuous power source for the supply of the railway remote controls equipment, with or without the accumulator battery assembled at the outlet (in the buffer).
The numeric command with the microprocessor allows the prescription of any level of voltage and the power in the admitted range, fact that makes possible the use at will and necessity.
Its main technical features are:
╖ The input voltage: 3 x 380 V/ 50 Hz +/- 20%;
╖ The adjustable voltage at outlet: continuous, between 144 and 210 Vcc;
╖ The variation of the outlet voltage: +/- 1%;
╖ The maximal power at the prescribed outlet: 45A;
╖ The protection at electric overload, including the short-circuit situation;
╖ Allows the operation in parallel with other similar rectifier equipment;
╖ High reliability during the operation;
╖ The power allowed at the outlet - the nominal one, as well as the one at short-circuit - can be prescribed, the precision being smaller than 1%.
The assembling and the putting into operation are quite facile; when connected, there should be granted a great attention to strictly respect the stipulated polarities: the plus and the minus pointed out at the outlet of the rectifier equipment should correspond with the plus and the minus of the accumulating battery; contrary, there is the risk to damage the rectifier equipment.

Three-phased inverter of ISTA 3-178, ISTA 5-178 types

This is meant to supply with three-phased voltage of 380 V/50 Hz of the asynchronous engines which the switch electro-mechanisms from CED stations are equipped with.
Its main technical features are:
╖ The supply voltage: 178 Vcc +/- 20%;
╖ The outlet voltage: 3 x 380 Vca, 50 Hz, with accessible null;
╖ The variation of the outlet voltage: +/- 5%;
╖ Power: 3,000 or 5,000 VA;
╖ The protection at electric overload, including the short-circuits situation;
╖ The automatic disconnection at the outlet from the admitted range of supply;
╖ The possibility to be put in dependency with a similar inverter (the commuting time is of maximum 2 seconds) or directly with the network;
╖ High reliability during the operation.

Rectifier equipment from contact line of RLC 40A/178 V type

This is meant to replace the three-phased rectifier equipment of DCS type when the three-phased voltage lacks (the normal distribution network). It is a mono-phased rectifier equipment supplied through a recessive transformer which takes over the necessary energy from the voltage of 25 kV (-30%Е+20%) from the contact line.
The numeric command with microprocessor allows the prescription of any level of voltage and of the power from the admitted range, fact that makes possible the use at will and according to the necessity.
Its main technical features are:
╖ The input voltage: 3 x 380 V/50 Hz +/_ 20%;
╖ The adjustable outlet voltage: between 144 and 210 Vcc;
╖ The variation of outlet voltage: +/- 1%;
╖ The prescribed outlet maximal power: 45A;
╖ The protection at the electric overload, including at short-circuit situation;
╖ Allows the operation in parallel with another similar rectifier equipment;
╖ The high reliability during the operation.
The admitted outlet power - the nominal one, as well as the one at short-circuit - can be prescribed, the precision being smaller than 1%.
The assembling and putting into operation of the function are facile; when connected there should be paid a greater attention to strictly respect the stipulated polarities: the plus and the minus pointed out at the outlet of the rectifier equipment should correspond with the plus and the minus of the accumulator battery; contrary, there is the risk of damaging of the rectifier equipment.

Rectifier equipment of DCS 2 x 25 A /20 V DCS 2 x 63 A/20V types
This is meant the supply of CED equipment, with or without the accumulator batteries in the buffer. It contains two identical rectifier equipment, with separate outlet terminals allowing the use at will and according to the necessity - either individual, or in series, or in parallel.
Its main technical features are:
╖ The input voltage: 220 Vca +/- 20%;
╖ The nominal outlet voltage: 2 x 12 Vcc;
╖ The variation of outlet voltage: +/- 1%;
╖ The adjustable field of the outlet voltage: 0Е20 V;
╖ The outlet power: 2 x 25A or 2 x 63 A;
╖ The protection at the electric overload, including at short-circuit situation;
╖ The high reliability during the operation.

The introduction of these new supply sources has fully satisfied up to the present time. Even if there was initially a series of question marks with regard to their well operation, their exploitation has certainly demonstrated that the new technical solutions are globally increased the reliability of the safety electro-supply, in order to provide the operation regime required by the new accumulator battery, achieved in closed vessels, made of polypropylene. Due to these sources there were no parts in motion, their maintenance is extremely facile, the producer recommending that at 12 months to blow with air the dust that has been deposited and, on this occasion, to be visually checked the existence of certain eventual aged insulation or of certain hot spots, caused by certain weakened clenched.

The equipment are delivered with quality certificate, the producer granting a guarantee of one year from the putting into operation, within 8 months since the delivery.

Alexandru Iulian Stan
Magdalena Fedeles