Converters for DC electric drives

Thyristor converter for current 10000A to voltage 930V

The converters may be used in electric drive systems of main machines applied in different types of industries, including integrated and nonintegrated steelworks, mechanical engineering, mining. etc.

By using converters in electric drives you can achieve:

• Smooth acceleration within a specified amount of time.
• Highly accurate multi-period velocity diagram of the machine as per requirements regardless of load changes.
• Speed stabilization during uniform motion periods.
• Clearance take-up in mechanical transmissions.
• Electric drives load levelling (for dual-motor drives) at all intervals of motion.
• Regenerative braking and avalanche deceleration back-to-back;
• Highly accurate shutdown without using mechanical brakes.
• Drive underspeed operation without unproductive losses of power.
• Drive braking mode that allows energy recovery to the supply network.
• Successful replacement of voltage-control systems that are still used at certain enterprises.
• Minimum breaking-in period due to simple and user-friendly interface for your staff.
• Minimum downtime due to advanced and simple built-in troubleshooting system in KTE5.
• Adjustment of all known electric drive coordinates (speed, tension, position).

As a part of a delivery, converters can be supplied with auxiliary equipment that can expand their functionality. The areas of equipment’s application include all industries of manufacturing and agricultural sector. Products comply with requirements of GOST 18142.1, GOST 24682, GOST 15963 and are manufactured according to the specifications of TU U 31.1-13626132-001: 2008.

The KTE5 series thyristor converters of the 5th generation are made in the following modifications: power range from 1 kW to 16 MW, rated rectified currents from 10A to 16 kA and rectified voltages up to 1200V. 6-pulse and 12-pulse rectification circuits without parallel connection of thyristors to the currents full range. 24-pulse rectification circuit for parallel operation of converters.

General characteristics

Converters for DC electric drives allow for armature circuit overloading as per values in the table below:

Overloading of converters used for power supply of electromagnetic loads and exciters should not exceed 130%.

In addition to a general-purpose industrial configurations, the series also include:

• special configuration for severe operating conditions: natural air cooling for currents up to 10 kA, overcurrent upto 2.5I for 10 sec (consistent with similar characteristics of engines and transformers);
• container versions for drilling pumps electric drives;
• block (built-in) versions using Customer’s reactor and transformer systems as well as protection switching equipment;
• cabinets for electric drives redundancy and distribution cabinets for multi-motor electric drives;
• control panels with manual controlling devices and embedded controllers or industrial computers;
• ComplexPro – embedded technological controller with open architecture and problem-oriented programming language for flexible changes of system functions during setup and operation;
• built-in electrical signals recorder SR-91A with a recording speed of up to 250 μs / point that provide for continuous monitoring of analog and digital signals and outputting measured parameters and states in a graphic form.

Since converters, cabinets and control panels are component-based and assemblable products this allows to:

• increase product’s mounting readiness;
• exclude their excessiveness;
• exclude additional automation controllers for the whole object.

Control system

• all versions of KTE5 have a uniform CS which also is consistent with CSs of other products made by our enterprise, in particular intelligent control panels, troubleshooting systems, devices for remote input/output, exciters of synchronous motors, turbo- and hydro-generators excitations, starters;
• CSs allow to receive and process signals from all sensors – pulse transducers, encoders, syncrodrives, temperature sensors, etc., including sensors with serial lines;
• the component parts for CSs, including low-voltage devices (relays, terminal connectors, etc.) are made of components by world leading manufacturers;
• CSs have high-speed industrial interfaces for communication with top-level equipment – ProfiBus DP, CAN, Modbus RTU, Modbus TCP / IP;
• it is possible to include SINAMICS DCM control units made by Siemens into the delivery set.

Protection system

KTE5 ensures the following types of protection and blocking:

• external and internal short circuits;
• inadmissible by rate and duration overloading currents of the main circuit elements and powered motors (time-current protection);
• cooling system breakdown;
• over- and undervoltage protection;
• supply voltage phase interruption;
• engine excess EMF;
• engine overspeeding;
• stop (mode) under load current;
• inadmissible reduction of station auxiliaries voltage;
• KTE5 activation if velocity demand is applicable;
• KTE5 activation when engine is rotating;
• power sources malfunction protection;
• activation blocking amid emergency and warning signals.

Controlling system parameters:

The controlling system implements all known positioning data for current, voltage, speed, EMF, tension, position.

Service options

The KTE controlling systems provide the user with a number of service options:

1. Flexible adjustment of automatic control structure
   For this purpose, the console terminal embedded into a specific service software controlling system can be used.
2. Real-time access to all adjustable parameters of the converter and electric drive via the console terminal.
   The Parameters are displayed in numerical decimal form on a single-line display of the console terminal.
3. Self-adjustment of certain adjustable parameters of the electric drive.
4. Detailed indication for activated protection types.
   When protection is activated, the list of all activated protection types is displayed on the console terminal in alphabetical order, starting from the first activated protection type and followed by all subsequent types.
5. Auto recording of the accident “track”.
   The recording is conducted by a built-in software titled “Track”.

Composition of armature circuit power converters (КТE5-A):

• Motor armature DC power system;
• A built-in excitation winding power system for motor excitation currents of up to 50A;
• A separate device for excitation winding power supply (KTE5-B) for motor excitation currents exceeding 50A;
• Control system.

Below you can find a drawing of the converter KTE5-AS-1k /440-ER2637-V00-UHL4 as an example

КТЕ5-М

General characteristics

The converter can be used in voltage-control systems as a controllable power supply for motor excitation winding.
The product’s microprocessor control system implements a subordinate automatic control system containing a motor speed controller, a current controller, a voltage controller, and a motor EMF controller for systems with motor excitation current control.

The saving mode and field suppression mode are implemented too.

• Rated currents: from 25 to 1000A;
• Rated voltages: from 110 to 460V;
• Power Units – reversible and non-reversible thyristor 6-pulse rectifiers.

On a drawing below you can see the converter KTE5-MS-500 /460-ER1100-V00-UHL4 as an example

Industrial configuration

• Cabinet and block versions;
• Depending on the scope of delivery, the product may include:
  – power rectifier and control system for generator excitation;
  – may include a power rectifier and a control system for motor excitation;
  – power transformer;
  – switch on the AC side;
  – downstream overvoltage protection device.
• Tools of local control and administration:
  – generator current and voltage excitation devices, motor excitation current device (with combined excitation control of the generator and the motor);
  – Lamps: “Power supply”, ‘Readiness”, “Warning”, “Accident”;
  – Setpoint handler “Manual setting”;
  – Console terminal;
  – Other tools of control and administration on demand of the customer.
• All tools of local control and administration can be duplicated on the control panel.

KTE5-B

General characteristics

The converter can be used in voltage-control systems as a controllable power supply for motor excitation winding. Additionally these series of converters can be used as motor exciters in thyristor converter-motor systems. reversive configurations can be applied in thyristor converter-motor systems with reversal of the field.
They can also be used as power supply for electromagnetic loads of various applications, including sources of operational voltage.
The product’s microprocessor control system implements a subordinate automatic control system containing a voltage controller and a current controller. By a simple change of settings, the converter can be used both as a current stabilizer and as a voltage regulator.

The saving mode and field suppression mode are implemented too.

• Rated currents: from 25 to 1000A;
• Rated voltages: from 110 to 460V;
• Power Units – reversible and non-reversible thyristor 6-pulse rectifiers.

On a drawing below you can see the converter KTE5-BC-200 /460-ER1100-V00-UHL4 as an example

Industrial configuration

• Cabinet and block versions;
• Depending on the scope of delivery, the product may include:
  – power rectifier and control system;
  – choke coil on the AC side or power transformer;
  – switch on the AC side;
  – downstream overvoltage protection device.
• Tools of local control and administration:
  – current and voltage excitation devices;
  – Lamp signalling: “Power supply”, ‘Readiness”, “Warning”, “Accident”;
  – Setpoint handler “Manual setting”;
  – Console terminal;
  – Other tools of control and administration on demand of the customer.
• All tools of local control and administration can be duplicated on the control panel;

Additional devices, which can serve as complex elements to solve the tasks of the drive:

• Cabinets with low-voltage equipment;
• Transfer switch cabinets;
• Control panels;
• Local automation controllers based on automation equipment from any supplier – Siemens, Shneder Electric etc.;
• Devices for remote input/output;
• Converters diagnostics system.

Electric drive diagnostics system

For deliveries of several KTE5 products to one facility, we are offering a delivery of converters and electric drives diagnostic system.