Three Phase Wound Rotor Synchronous Machine with Neutral Connection (VBR)
Description of the Three Phase Wound Rotor Synchronous Machine with Neutral Connection (VBR) component in Schematic Editor.
Component | Component dialog window | Component parameters |
---|---|---|
|
A, B, and C are stator winding terminals. Terminal N represents the neutral point of the star (Y) connected stator windings. The stator winding uses the voltage behind reactance interface. R1 and R2 represent field winding terminals. The rotor winding uses the single phase variant of the current source interface.
Electrical sub-system model
The electrical part of the machine is represented by the following system of equations, modeled in the rotating dq reference frame. The dq reference frame is attached to the rotor, and the direct axis is aligned with the rotor magnets. The modeled dynamics can be represented with the following equations:
If the saturation effects are considered, the equations have the same form, but in that case fluxes are functions of stator currents:
where:
and:
All rotor variables and parameters are referred to the stator with an appropriate turns ratio. To illustrate this, if you apply voltage vfdr at the field winding terminals, it is transformed to the stator value, vfd with the following equation:
Similarly, the calculated rotor field winding current ifd is referred back to the real rotor windings value ifdr through the following equation:
Symbol | Description |
---|---|
ψds | Direct axis component of the stator flux [Wb] |
ψqs | Quadrature axis component of the stator flux [Wb] |
ψ0s | Zero axis component of the stator flux [Wb] |
ψkd | Direct axis component of the damper winding flux, referred to the stator [Wb] |
ψkq | Quadrature axis component of the damper winding flux, referred to the stator [Wb] |
ψfd | Field winding flux, referred to the stator [Wb] |
ψkq2 | Second quadrature axis component of the damper winding flux, referred to the stator [Wb] |
ids | Direct axis component of the stator current [A] |
iqs | Quadrature axis component of the stator current [A] |
i0s | Zero axis component of the stator current [A] |
ikd | Direct axis component of the damper winding current, referred to the stator [A] |
ikq | Quadrature axis component of the damper winding current, referred to the stator [A] |
ifd | Field winding current, referred to the stator [A] |
ifdr | Field winding current [A] |
ikq2 | Second quadrature axis component of the damper winding current, referred to the stator [A] |
vds | Direct axis component of the stator voltage [V] |
vqs | Quadrature axis component of the stator voltage [V] |
v0s | Zero axis component of the stator voltage [V] |
vkd | Direct axis component of the damper winding voltage, referred to the stator [V] |
vkq | Quadrature axis component of the damper winding voltage, referred to the stator [V] |
vfd | Field winding voltage, referred to the stator [V] |
vfdr | Field winding voltage [V] |
vkq2 | Second quadrature axis component of the damper winding voltage, referred to the stator [V] |
imd | Direct axis component of the magnetizing current [A] |
imq | Quadrature axis component of the magnetizing current [A] |
ψmd | Direct axis component of the magnetizing flux [Wb] |
ψmq | Quadrature axis component of the magnetizing flux [Wb] |
im | Magnetizing current [A] |
ψm | Magnetizing flux [Wb] |
Rs | Stator phase resistance [Ω] |
Rkd | Direct axis damper winding resistance, referred to the stator [Ω] |
Rkq | Quadrature axis damper winding resistance, referred to the stator [Ω] |
Rkq2 | Second quadrature axis damper winding resistance, referred to the stator [Ω] |
Rfd | Field winding resistance, referred to the stator [Ω] |
Lls | Stator phase leakage inductance [H] |
Lmd | Direct axis magnetizing (mutual, main) inductance [H] |
Lmq | Quadrature axis magnetizing (mutual, main) inductance [H] |
Llkd | Direct axis damper winding leakage inductance, referred to the stator [H] |
Llkq | Quadrature axis damper winding leakage inductance, referred to the stator [H] |
Llkq2 | Second quadrature axis damper winding leakage inductance, referred to the stator [H] |
Llfd | Direct axis field winding leakage inductance, referred to the stator [H] |
Lc | Canay leakage inductance, referred to the stator [H] |
ωr | Rotor electrical speed [rad/s] ( ) |
p | Machine number of pole pairs |
Te | Machine developed electromagnetic torque [Nm] |
Ns/Nfd | Turns ratio between stator phase winding and field winding used for transforming field winding variables to the stator-side |
Mechanical sub-system model
Motion equation:
symbol | description |
---|---|
ωm | Rotor mechanical speed [rad/s] |
Jm | Combined rotor and load moment of inertia [kgm2] |
Te | Machine developed electromagnetic torque [Nm] |
Tl | Shaft mechanical load torque [Nm] |
b | Machine viscous friction coefficient [Nms] |
θm | Rotor mechanical angle [rad] |
Electrical
This component offers two levels of model fidelity, designated by the Model Type property. The following options are available:- linear
- nonlinear
- no load curve
- flux vs current
symbol | description |
---|---|
Number of damper windings | Switches the number of damper windings in the machine model, causing the state space model to be either of a sixth-order or a fifth-order by removing all variables and parameters associated with a second winding |
Rs | Stator phase resistance [Ω] |
Lls | Stator phase leakage inductance [H] |
Lmd | Direct axis magnetizing (mutual, main) inductance [H] |
Lmq | Quadrature axis magnetizing (mutual, main) inductance [H] |
Rf | Field winding resistance, referred to the stator [Ω] |
Llfd | Direct axis field winding leakage inductance, referred to the stator [H] |
Rkd | Direct axis damper winding resistance, referred to the stator [Ω] |
Rkq | Quadrature axis damper winding resistance, referred to the stator [Ω] |
Rkq2 | Second quadrature axis damper winding resistance, referred to the stator [Ω] |
Llkd | Direct axis damper winding leakage inductance, referred to the stator [H] |
Llkq | Quadrature axis damper winding leakage inductance, referred to the stator [H] |
Llkq2 | Second quadrature axis damper winding leakage inductance, referred to the stator [H] |
Ns/Nfd | Turns ratio between stator phase winding and field winding used for transforming field winding variables to the stator-side |
Lc | Canay leakage inductance, referred to the stator [H] |
rated speed | Machine mechanical rated speed used in nonlinear model for magnetizing curve defined as no load curve [rpm] |
if vector | List of no load excitation current [A] |
vs vector | List of no load stator line-to-line RMS voltage [V] |
imd vector | List of magnetizing current direct axis component values [A] |
imq vector | List of magnetizing current quadrature axis component values [A] |
psimd table | Table of magnetizing flux direct axis component values [Wb] |
psimq table | Table of magnetizing flux quadrature axis component values [Wb] |
The Three Phase Wound Rotor Synchronous Machine with Neutral Connection (VBR) machine model can include magnetic saturation effects. In that case, fluxes are defined as functions of magnetizing currents imd and imq. These functions are represented in the form of lookup tables. The lookup tables use linear interpolation and linear extrapolation.
- no load curve
- flux vs current
if_vector = [0, 4514.0, 9498.0, 13260.0, 15260.0, 16710.0, 18200.0, 19210.0, 21340.0, 23650.0, 25930.0]
vs_vector = [0.0, 4986.55, 10388.65, 14313.256, 16298.64, 17637.6, 18884.26, 19623, 20915.82, 22116.28, 23224.4]
imd_vector = [-9498.0, -8548.2, -7598.4, -6648.6, -5698.8]
imq_vector = [-9498.0, -8548.2, -7598.4, -6648.6, -5698.8]
psimd_table = [-22.46306805, -20.2273073, -17.99014399, -15.75121391, -13.51008229]
psimq_table = [-11.07784855, -9.9724961, -8.86656821, -7.76004375, -6.65291642]
imd_vector = [-9498.0, -8548.2, -7598.4, -6648.6, -5698.8]
imq_vector = [-9498.0, -8548.2, -7598.4, -6648.6, -5698.8]
psimd_table = [[-22.46306805, -22.46854837, -22.47394023, -22.47914448, -22.48404604],
[-20.2273073, -20.23340111, -20.23948657, -20.24544982, -20.25115112],
[-17.99014399, -17.99688273, -18.00373418, -18.01057435, -18.01723878],
[-15.75121391, -15.75858553, -15.7662438, -15.77406724, -15.78187459],
[-13.51008229, -13.51799327, -13.52642503, -13.53528506, -13.54440031]]
psimq_table = [[-11.07784855, -9.9724961, -8.86656821, -7.76004375, -6.65291642],
[-11.08362731, -9.97826979, -8.87224078, -7.765498, -6.65801557],
[-11.08998614, -9.9847262, -8.87869102, -7.77180627, -6.6640132],
[-11.09691706, -9.99189941, -8.88600464, -7.77911226, -6.67111073],
[-11.10434879, -9.99976596, -8.89422511, -7.7875446, -6.67953349]]
Mechanical
symbol | description |
---|---|
pms | Machine number of pole pairs |
Jm | Combined rotor and load moment of inertia [kgm2] |
Friction coefficient | Machine viscous friction coefficient [Nms] |
Unconstrained mechanical angle | Limiting mechanical angle between 0 and 2π |
Load
symbol | description |
---|---|
Load source | Load can be set from SCADA/external or from model (in model case, one signal processing input will appear) |
External/Model load type | External/Model load type: torque or speed |
Load ai pin | HIL analog input address for external torque command |
Load ai offset | Assigned offset value to the input signal representing external torque command |
Load ai gain | Assigned gain value to the input signal representing external torque command |
External load enables you to use an analog input signal from a HIL analog channel with the load_ai_pin address as an external torque/speed load, and to assign offset (V) and gain (Nm/V) to the input signal, according to the formula:
Feedback
symbol | description |
---|---|
Encoder ppr | Incremental encoder number of pulses per revolution |
Encoder Z pulse length | Z digital signal pulse length in periods. Can be Quarter length or Full period (default) |
Resolver pole pairs | Resolver number of pole pairs |
Resolver carrier source | Resolver carrier signal source selection (internal or external) |
External resolver carrier source type | External resolver carrier signal source type selection (single ended or differential); available only if the Resolver carrier source property is set to external |
Resolver carrier frequency | Resolver carrier signal frequency (internal carrier) [Hz] |
Resolver ai pin 1 | Resolver carrier input channel 1 address (external carrier) |
Resolver ai pin 2 | Resolver carrier input channel 2 address (external carrier); available only if the External resolver carrier source type property is set to differential |
Resolver ai offset | Resolver carrier input channel offset (external carrier) |
Resolver ai gain | Resolver carrier input channel gain (external carrier) |
Absolute encoder protocol | Standardized protocol providing the absolute machine encoder position |
If an external resolver carrier source is selected, the source signal type can be set as either single ended or differential. The single ended external resolver carrier source type enables use of an analog input signal from the HIL analog channel with the res_ai_pin_1 address as the external carrier source. Additionally, offset (V) and gain (V/V) values can be assigned to the input signal, according to the formula:
The differential external resolver carrier source type enables use of two analog input signals from the HIL analog channels with the res_ai_pin_1 and the res_ai_pin_2 addresses. Analog signals from these HIL analog inputs are subtracted, and the resulting signal is used as the external differential carrier source. Additionally, offset (V) and gain (V/V) values can be assigned to the input signal (similarly to the single ended case), according to the formula:
The following expression must hold in order to properly generate the encoder signals:
symbol | description |
---|---|
enc_ppr | Encoder number of pulses per revolution |
fm | Rotor mechanical frequency [Hz] |
Ts | Simulation time step [s] |
Advanced
symbol | description |
---|---|
Theta_ab | Position of the stationary αβ reference frame, in respect to the stator phase a axis [rad] |
The machine model output variables (currents, voltages and fluxes) can be observed from a stationary reference frame. There are two widely used approaches in electrical machine modeling: in the first, the alpha axis of the stationary reference frame lags by 90 degrees in regard to the stator phase a axis (used by default, and indicated in a) Figure 6. In the second one, the alpha axis is aligned with the stator phase a axis (indicated in b) Figure 6. The user can select between these two situations.
It is important to know the value of Theta_ab when the rotor position feedback is necessary. As an example, if a model uses the mechanical angle as a feedback signal and feeds it to one of the abc to dq, alpha beta to dq, dq to abc, or dq to alpha beta transformation blocks, the same transformation angle offset value should be used in both components to ensure the expected simulation results.
Output
This block tab enables a single, vectorized signal output from the machine. The output vector contains selected machine mechanical and/or electrical variables in the same order as listed in this tab.
symbol | description |
---|---|
Execution rate | Signal processing output execution rate [s] |
Electrical torque | Machine electrical torque [Nm] |
Mechanical speed | Machine mechanical angular speed [rad/s] |
Mechanical angle | Machine mechanical angle [rad] |
Stator alpha axis emf | Alpha axis component of the stator VBR equivalent back emf [V] |
Stator beta axis emf | Beta axis component of the stator VBR equivalent back emf [V] |
Stator d-axis emf | Direct axis component of the stator back emf [V] |
Stator q-axis emf | Quadrature axis component of the stator back emf [V] |
Magnetizing d-axis flux | Direct axis component of the magnetizing flux [Wb] |
Magnetizing q-axis flux | Quadrature axis component of the magnetizing flux [Wb] |
Stator d-axis current | Direct axis component of the stator current [A] |
Stator q-axis current | Quadrature axis component of the stator current [A] |