Fault-Tolerant Power Electronic System for Drag Power Kites
Table 5
Relevant parameters of the demonstrator other than in Table 3. The rows in bold are only relevant for a circuit simulation of the demonstrator with ground converters.
Parameter
Symbol
Value
Comment
Design choices
Number of drivetrain groups
2
Demonstrator design
Number of cable pairs per drivetrain group
1
Demonstrator design
Rated values
Rated voltage
24 V
A 12 V lead acid battery was used as a UPS (or generally as a power supply)
Rated power
W
approx. value for used RC rotor drives
Rated current of one drivetrain
5 A
Two drivetrain groups
Filter capacitances
Capacitors
C2#
2.2 mF
Capacitance of built rotor drives
Capacitors
2 C1p# = 2 C1n#
C2#
Capacitance of built rotor drives
Parasitic resistances
Ground wire resistance
R1# + R2# = R3# + R4#
0.01
Estimated
Resistance of one wire
0.01 Ω
Estimated for used wires including connectors
Resistance of one cable shield
0.01 Ω
Estimated for used wires including connectors
Resistance of parallel tether shields
R10#
Only single cable used to emulate shield, therefore no parallel shields in a drivetrain
Resistance of other shields
Ro
No further drivetrains/shields used
Fuse ratings
Fuse timings
2 ms
Selected
Kite converter control parameters
Imbalance-voltage turn-off threshold
Imbalance not measured and not used
Imbalance-voltage turn-off threshold
0.33Ur
in simulation with ground converter: same as in Table 3
UPSs
UPS voltage source
U1# = U2#
If no ground converters used, batteries are the only voltage source
UPS voltage source
U1# = U2#
U#,set/2
i.e., 90 of normal voltage
Parameters for acceptance criteria
Maximum wire steady-state current
If the voltages of the batteries are not exactly equal, in S5 and S13 up to twice the rated current can be expected in steady-state, i.e. in the worst case one drivetrain group’s batteries supply both drivetrain groups
