Component production for ripple control transmitters to 110kV

Technical parameters of ripple control stationary sources for networks up to 110kV, produced by EPA :

Type: SMK 720 SMK 1600
Input supply voltage [V / (50 – 60)Hz]: 3 × 525
(3 × 400)x
3 × 525
(3 × 400)x
Input phase current [A / (50 – 60)Hz]: < 400 < 1050
Output phase tonal current [A]: < 440 < 900
Apparent output three-phase power [kVA]: 720
Operating frequency [Hz]: 170 – 770 170 – 500
Time long-term power carrying capacity [%]: 10 10
Assembly dimensions, inclusive control systems [mm]
– width:
– deep:
– height (without eyes and bases):


Number of boxes, inclusive control systems: 2 4
Volume utilization of power [kVA/m3]: 317

x – Possibility of variant input supplying and output power corresponding this situation.
xx – Volume utilization of power, typical for the previous type of transmitter for equal operating conditions.

Characteristics of power ripple control stationary sources for networks up to 110kV, produced by EPA :

SMK 720

  • A stationary ripple control transmitter in two-box version (GO + power unit box), intended primarily for transmitters to hv levels (up to 110kV), with tonal loading impedance greater than 20Ω at the operated tonal voltage level of 1.8 – 2.2%, in a block connection with one coupling element. It may be advantageously used also for extremely loaded ripple control transmitters to hv levels, particularly in consideration of more coupling elements in parallel connection.
  • At present, it is in operation in Bošáca (Slovakia – E.ON) substation.
  • The above-mentioned type supersedes the older ripple control transmitter with equal power situated in Tábor (E.ON) substation.

SMK 1600

  • Radically innovated ripple control transmitter with the greatest power intended for the control of extensive 110kV networks, the tonal impedance of which is greater than 10Ω at the required tone signal level of 1.8 – 2.2%, in a block connection with one coupling element with the basic parameter of maximum tonal current 140A to 110kV network.
  • At present, it is in operation in Praha – Chodov, Medzibrod, Považská Bystrica (both Slovakia), Čebín, Horní Životice, Krasíkov, Malešice, Neznášov, Opočínek, Vítkov and Týnec II. substations.
  • The above-mentioned type supersedes older ripple control transmitters with equal power.

Characteristics of control and operating systems for innovated stationary ripple control sources, produced by EPA :

  • The compact version of transmitter control and operating system, placed, in case of the SMK 720 and SMK 1600 types, to a separate box with the dimensions of 600 × 600 × 2000mm (allows controlling two power blocks for large transmitters to 110kV), in case of the SMK 250, the control and operating system is situated in one box together with the transmitter's power unit.
  • Control systems allow the automatic operation of the ripple control transmitter with continuous power regulation, the aim of which is to preserve a tonal signal level in the range of adjusted values, which supports fully operator-free equipment operation.
  • All critical transmitter parameters are real-time monitored and if any limit is exceeded an immediate response will follow (according to the program entered). For this purpose, one-chip computer circuits are used, which implement the whole transmitter operation optimization with the maximum utilizing of given performance possibilities. By this system, conditions for the whole equipment long-term lifespan are ensured, with the minimization of malfunctions leading to the necessity of operating staff intervention. The program entered was developed based on a long-term experience with this transmitter's type operation and derived from power circuits' analysis.
  • In case of a personal computer connection to the transmitter's control system (namely locally with a cable or remotely by a modem), the whole transmitter's operation may be monitored during the transmission of individual telegram control pulses; alternatively this transmission may be analyzed from an integral memory for several past weeks. This allows, in collaboration with the possible installation of memory analyzers, to identify prospective anomalous responses during the transmitter's operation and this way further to improve the quality of the equipment long-term operation. The new VLK 10 system (see information on the SMK 250 innovation) has a significantly extended function for remote communication, in the frame of diagnostics as well as control of transmitter operational parameters.
  • Control systems are fitted with the GPS sync circuits from a new series, which allow these transmitters' reliable power operation in a controlled area without exceptional requirements regarding connecting routes with the possibility of continuous sync angle adjusting via one-chip computers, which simplifies any measurement during commissioning.
  • The style of control system allows scale-up in the case of operator's nonstandard requirements regarding the way of the transmitter's monitoring.
  • Control systems are designed so as to enable expeditious identification of any malfunction in the case of its occurrence and pertinently, the whole equipment could be put into fully valuable operation by simple replacing one of functionally integrated components.


Items marked (*) are required.