Description
The figure below shows the model implementation of the DC circuit breaker model in HYPERSIM, adapted from [1]. The model is made up of two branches:
- the auxiliary branch - containing the Load Commutating Switch (LCS) and Ultra Fast Disconnector (UFD) breakers;
- the main branch - main circuit breaker with individual surge arresters forming a cell, and an option to select the number of such desired cells.
The individual surge arresters are rated to meet the full voltage and current breaking capability, and the auxiliary DC breaker for lower voltage and current capability.
Under normal operation, the current will flow only through the auxiliary branch and the current in the main breaker is zero. When a DC fault occurs, the LCS immediately commutates the current to the main DC Breaker and the fast disconnector opens. With the mechanical switch in open position, the main DC breaker breaks the current.
The LCS and main breaker switches are based on IGBT and the model allows the user to select the number of IGBTs in series and parallel. The model allows the user to select the switching times of the LCS, UFD, main breakers, and the number of switching times enabled for each breaker (up to 4).
Note:
- All switching times are given relative to the trigger signal
- Each T1 to T4 value must be larger than the previous one, i.e.: T1 < T2 < T3 < T4. Otherwise, only the first switching time respecting that condition will be operated
Mask and Parameters
General
Name | Description | Units | Variable = {Possible Values} |
|---|---|---|---|
Control type
| Internal: uses switching times defined on Timing tab. External (input pins) to use signals from the input pins | - | |
Number of cells in main breaker | Number of cells in the main breaker. From 1 to 10. | - | {1,10} |
Include inductance | Include Inductance when checked | - | |
Resistor | Parallel resistance | Ohm | {0,1e12} |
Inductance | Series inductance | H | {0,1e12} |
Number of IGBTs in parallel in the LCS | Number of IGBTs in parallel in the LCS | - | |
Number of IGBTs in parallel in each cell | Number of IGBTs in parallel in each cell | - | |
Number of IGBTs in series in the LCS | Number of IGBTs in series in the LCS | - | |
Number of IGBTs in series in each cell | Number of IGBTs in series in each cell | - |
Timing
Name | Description | Units | Variable = {Possible Values} |
Breaker initial state | Initial state of the corresponding breaker. Open or closed. | - | |
T1, T2, T3, T4 | Four switching times of the corresponding breaker (closing time if initial state is open, opening time otherwise) | s | {0,1e12} |
Number of switching times enabled | Number of switching times enabled from 0 to 4. For instance, 2 means only the two first switching are considered. | - | {0,1,2,3,4} |
Surge arrester
Name | Description | Units | Variable = {Possible Values} |
Points in Zno characteristic | Number of points in Zn0 characteristic. Note: First point must be 0,0 | - | {1,12} |
Voltage | All voltage points of the Zn0 characteristic | V | {0,1e12} |
Current | All current points of the Zn0 characteristic | A | {0,1e12} |
Advanced
Name | Description | Units | Variable = {Possible Values} |
Ron resistance for each IGBT | Resistance for each IGBT when closed | Ohm | {0,1e12} |
Ron resistance for each IGBT | Resistance for each IGBT when open | MOhm | {0,1e12} |
Ron resistance for ultra fast disconnector | Resistance of the UFD when closed | Ohm | {0,1e12} |
Roff resistance for ultra fast disconnector | Resistance of the UFD when open | MOhm | {0,1e12} |
Ports, Inputs, Outputs and Signals Available for Monitoring
Ports
| Name | Description |
|---|---|
| Net_1 | Network connection; the "+" indicates the current measurement direction |
| Net_2 | Network connection |
Input
I/O NAME | TYPE (UNIT) | DESCRIPTION |
Trig | Input (command signal) | Triggering signal. The switching times of the breakers are defined as relative to this signal. Trigger happens when the input is more than threshold value 0.5 |
ExtCtrl - LCS | Input (command signal) | Command signal of the LCS. Used only if the control type is set to External (input pins) |
ExtCtrl - UFD | Input (command signal) | Command signal of the UFD. Used only if the control type is set to External (input pins) |
ExtCtrl - Bsig | Input (command signal) | Command signal of the breakers on main branch. Used only if the control type is set to External (input pins). Bundle of size 10. Unconnected pins will be set to 0, which is an “Open” signal to the breaker. |
Imain_scp | Output (A) | Current on the main branch |
Iaux_scp | Output (A) | Current on the auxiliary branch |
Output
None
Sensors
| Name | Description | Unit |
|---|---|---|
| Bx (x=1 to 10) | Status of each breaker | |
| Trig | Trigger signal status | |
| UFD | Status of UFD | |
| LCS | Status of LCS | |
| I_aux | Current though auxiliary branch | A |
| I_main | Current though main branch | A |
| Bx_int (x=1 to 10) | Internal controlled breaker status | |
| LCS_int | Internal controlled LCS status | |
| UFD_int | Internal controlled UFD status | |
| iSegb_x (x=1 to 10) | Status of breaker cells selected | |
| IZnox (x = 1 to 10) | Current through main branch surge arresters | A |
References
- J. Häfner, B. Jacobson, "Proactive Hybrid HVDC Breakers - A key innovation for reliable HVDC Grids", International symposium on Electric Power systems of the Future, 13-15 September, 2011