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SIMILAR PRODUCTS
SGMPH-01AAA41+SGDM-01ADA
SGMPH-01AAA4C+SGDM-01ADA
SGMPH-02AAA41+SGDM-02ADA
SGMPH-02AAA4C+SGDM-02ADA
SGMPH-04AAA41+SGDM-04ADA
SGMPH-04AAA4C+SGDM-04ADA
SGMPH-08AAA41+SGDM-08ADA
SGMPH-08AAA4C+SGDM-08ADA
SGMPH-15AAA41+SGDM-15ADA
SGMPH-15AAA4C+SGDM-15ADA
SGMPH-01AAA21+SGDM-01ADA
SGMPH-01AAA2C+SGDM-01ADA
SGMPH-02AAA21+SGDM-02ADA
SGMPH-02AAA2C+SGDM-02ADA
SGMPH-04AAA21+SGDM-04ADA
SGMPH-04AAA2C+SGDM-04ADA
SGMPH-08AAA21+SGDM-08ADA
SGMPH-08AAA2C+SGDM-08ADA
SGMPH-15AAA21+SGDM-15ADA
SGMPH-15AAA2C+SGDM-15ADA
SGMPH-01A1A41+SGDM-01ADA
SGMPH-01A1A4C+SGDM-01ADA
SGMPH-02A1A41+SGDM-02ADA
SGMPH-02A1A4C+SGDM-02ADA
SGMPH-04A1A41+SGDM-04ADA
SGMPH-04A1A4C+SGDM-04ADA
SGMPH-08A1A41+SGDM-08ADA
SGMPH-08A1A4C+SGDM-08ADA
SGMPH-15A1A41+SGDM-15ADA
SGMPH-15A1A4C+SGDM-15ADA
A phasor E, that can represent the voltage impressed on a circuit. The phasor is made of a vector with magnitude proportional to the magnitude of E, rotating at a constant rotational speed ω. The convention is that phasors rotate counterclockwise. The vertical projection of the phasor results in a sinusoidal representing the instantaneous voltage e existing at any time. In the graph, α = ω × t, where t is the time elapsed from its zero crossing. phenomenon in periodic circuits is that the resulting angle between the applied voltage and the current depends on certain characteristics of the circuit. These characteristics can be classified as being resistive, capacitive, and inductive. The angle between the voltage and the current in the circuit is called the power angle.
The cosine of the same angle is called the power factor of the circuit, or for short, the PF.
Note: As it will be shown latter, in synchronous machines the term power angle is used to identify a different concept. To avoid confusion, in this book the angle between the current and the voltage in the circuit will therefore be identified by the “power factor.”
In the case of a circuit having only resistances, the voltages and currents are in phase, meaning the angle between them equals zero. Figure 1.8 shows the various parameters encountered in a resistive circuit. It is important to note that resistances have the property of generating heat when a current flows through
them. The heat generated equals the square of the current times the value of the
resistance. When the current is measured in amperes and the resistance in ohms, the resulting power dissipated as heat is given in watts. In electrical machines this heat represents a loss of energy. It will be shown later that one of the fundamental requirements in designing an electric machine is the efficient removal of these resistive losses, with the purpose of limiting the undesirable temperature rise of the internal components of the machine.
In resistive circuits the instantaneous power delivered by the source to the load equals the product of the instantaneous values of the voltage and the current. When the same sinusoidal voltage is applied across the terminals of a circuit with capacitive or inductive characteristics, the steady-state current will exhibit
an angular (or time) displacement vis-a-vis the driving voltage.