Target Applications: Welding / spot welding equipment Presses (e.g. most car factories in Germany use meanwhile dynamic PFC) Wind turbines Container cranes Lifts Central motor start up compensation Any fast fluctuating load requires DYNAMIC PFC EPCOS AG FK PM PFC (RM)
DYNAMIC PFC
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What is DYNAMIC PFC? The usage of new technologies in modern industry claims for faster and more dynamic power factor correction banks that follow the faster process and allow a “real time” power factor correction. The solution is the so called “Dynamic Power Factor Correction”. Dynamic PFC systems use electronic switches rather than contactors – thyristor modules – which allow an infinite number of switching operations on one hand and ensures an extremely fast reaction time upon load changes. High inrush currents one of the big problems while switching shunt capacitors with conventional contactors are eliminated with Thyristor switches due to ZERO
CROSSING SWITCHING, means the
capacitor is connected during ZERO crossing of the sinusoidal wave and therefore no inrush currents are caused. EPCOS AG FK PM PFC (RM)
DYNAMIC PFC
30.04.2003
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Customer benefits of DYNAMIC PFC 1.
Elimination of reactive power drawn from power utilities, reduction of electricity cost also with fast fluctuating loads; duty cycles of a few seconds are possible
2.
Fast switching without delay time for discharging (< 20 ms)
3.
Cost saving: investment reduction for new equipment (distribution equipment, transformer, cable cross section etc.), due to cutting-off of peak loads
4.
Stabilizing of grid voltage, means avoiding of voltage drop, e.g. welding therefore improvement of welding process in terms of quality but also in time
5.
Avoiding of flickering
6.
Smooth switching, transients power quality will be improved
7.
Increase of life time of a capacitor bank due to contact less switching and smooth switching (switching device as well as capacitors) EPCOS AG FK PM PFC (RM)
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(voltage
DYNAMIC PFC
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30.04.2003
current),
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N E T Z
L A S T
EchtzeitBlindleistungsregler
TSM – C 1 ... n
Real time Power factor controller
DynamiC
Reaction-time: about 20 ms EPCOS AG FK PM PFC (RM)
DYNAMIC PFC
30.04.2003
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Features expected of dynamic PFC? Transient-free switching Power factor correction with high switching frequency Minimal reaction-time Free of wear out Enhancement of power quality Flicker-compensation EPCOS AG FK PM PFC (RM)
DYNAMIC PFC
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TSM-C Thyristor switch
TSM – C for Active (dynamic, real time) PFC Fast Thyristor switch for capacitive loads up to 50 kvar. The TSM-C is a fast electronically controlled, selfobserving thyristor switch for capacitive loads up to 50 kvar, which is capable to switch PFC capacitors within a few milliseconds as often as required.
EPCOS AG FK PM PFC (RM)
DYNAMIC PFC
30.04.2003
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TSM-C Thyristor switch The TSM-C observes permanently: - voltage (availability & value) - phase sequence - capacitor rated current - temperature of the power switches When voltage problems occur, the TSM turns-off. By supervising of the capacitor-current it is possible to identify dangerous operating conditions, such as harmonic distortion. High current harmonics may cause the destruction of the connected PFC capacitor. Over currents are measured by an integrated measuring system. The module turns-off as long as the overload exists. The highly advanced measuring circuit for self-observing of the thyristor switch protects the capacitor and the application as well. The alarm-signal of the temperature trigger switches-off the corresponding capacitor branch. After dis-connection the thyristor switch will cool down again, if the temperature decreases below the preset threshold value, the module will reconnect. EPCOS AG FK PM PFC (RM)
DYNAMIC PFC
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TSM-C Features: 1.
Easy installation: it can be used identically as a contactor and can be put into operation even with a standard controller (our recommendation is the BR6000-T controller with transistor output). All the intelligence needed is offered with the thyristor module itself.
2.
The TSM-C is a fast electronically controlled, self-observing power switch for capacitive loads up to 50 kvar
3.
Due to “full wave switching” no harmonics generated by TSM-C
4.
Very fast reaction time: < 7 milliseconds only
5.
Permanent self-controlling of: - voltage parameter - capacitor-current - temperature of the thyristor-switch.
6.
Cascading output
7.
Alarm output per module
8.
Compact and modern design
EPCOS AG FK PM PFC (RM)
DYNAMIC PFC
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TSM-C high end design : 1.
Modern design with compact casing
2.
2 high voltage thyristor modules
3.
2 large heat sinks
4.
2 current transformer
5.
Intelligent control board for zero crossing switching
6.
Firing board for thyristor firing
7.
PCB for self diagnostic of all important electrical and thermal parameters
8.
Front plate with operation and error message display
EPCOS AG FK PM PFC (RM)
DYNAMIC PFC
30.04.2003
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Comparison of inrush current
Left hand graph shows a inrush current of 157 times nominal current caused by PFC capacitor parallel switching with standard motor contactor.
EPCOS AG FK PM PFC (RM)
The thyristor connects the capacitor with almost Zero delay time. As soon as the control signal is applied to the thyristor, it starts carrying the capacitor current, means ULTRA FAST switching. At the same time this graph shows that the current is starting from ZERO (Xaxis), up to its maximum value without any inrush current effect. >> no inrush current
