Compute positive-sequence active and reactive powers - Simulink - MathWorks 日本 - 金宝app,下载188bet金宝搏,金宝搏官方网站

Description

The Power (Positive-Sequence) block computes the positive-sequence active power P (in watts) and reactive power Q (in vars) of a periodic set of three-phase voltages and currents. To perform this computation, the block first computes the positive sequence of the input voltages and currents with a running window over one cycle of the specified fundamental frequency. These formulas are then evaluated:

$\begin{matrix} P = 3 \times \frac{| V_{1} |}{\sqrt{2}} \times \frac{| I_{1} |}{\sqrt{2}} \times \cos (φ) \\ Q = 3 \times \frac{| V_{1} |}{\sqrt{2}} \times \frac{| I_{1} |}{\sqrt{2}} \times \sin (φ) \\ φ = ∠ V_{1} - ∠ I_{1} \end{matrix}$

V₁is the positive-sequence component of input Vabc. I₁是输入Iabc的正序分量。

A current flowing into an RL circuit produces a positive P and a positive Q.

As this block uses a running average window, one cycle of simulation must complete before the outputs give the correct value. For the first cycle of simulation, the output is held constant using the values specified by theVoltage initial inputandCurrent initial inputparameters.

Parameters

Fundamental frequency (Hz): Specify the fundamental frequency, in hertz, of the input signals. Default is60.
Voltage initial input [ Mag, Phase (degrees) ]: Specify the voltage initial magnitude and phase used by the block to compute the constant output for the first cycle of simulation. Default is[0, 0].
Current initial input [ Mag, Phase (degrees) ]: Specify the current initial magnitude and phase used by the block to compute the constant output for the first cycle of simulation. Default is[0, 0].
Sample time: Specify the sample time of the block, in seconds. Set to0to implement a continuous block. Default is0.

Inputs and Outputs

Vabc: The three-phase voltage signal.
Iabc: The three-phase current signal.
P: The positive-sequence active power, in watts.
Q: The positive-sequence reactive power, in vars.

Characteristics

Sample Time	Specified in theSample Timeparameter Continuous ifSample Time= 0
Scalar Expansion	No
Dimensionalized	No

Examples

Thepower_ThreePhasePowermodel compares the outputs of the Power (Positive-Sequence) block with the Power (3ph, Instantaneous) and the Power (dq0, Instantaneous) block. The Power (Positive-Sequence) block gives ripple-free accurate results even with the presence of zero and negative sequences in the voltage supply.

The model sample time is parameterized by the Ts variable set to a default value of 50e-6 s. Set Ts to 0 in the command window and change theSimulation typeparameter of the Powergui block toContinuousto simulate the model in continuous mode.

Power (Positive-Sequence)

Library

Description

Parameters

Inputs and Outputs

Characteristics

Examples

Version History