Lecture #6 Power System Reactive power and voltage control Dr.Qi Huang School of Energy Science and Engineering,UESTC
Lecture #6 Power System Reactive power and voltage control Dr. Qi Huang School of Energy Science and Engineering, UESTC
Contents Introduction Concept of Reactive power in power system Control and management of reactive and voltage Difference between active power frequency regulation Importance of voltage control Measures for voltage control Rules of reactive compensation and voltage control Excitation control of generator 电力拿镜广城洲量写控制四川省童点实验蜜 家电
电力系统广域测量与控制四川省重点实验室 Contents Introduction Concept of Reactive power in power system Control and management of reactive and voltage Difference between active power & frequency regulation Importance of voltage control Measures for voltage control Rules of reactive compensation and voltage control Excitation control of generator
Concept of reactive power Power in an electric circuit is the rate of flow of energy past a given point of the circuit.In alternating current circuits,energy storage elements such as inductance and capacitance may result in periodic reversals of the direction of energy flow. 口 The portion of power that,averaged over a complete cycle of the AC waveform,results in net transfer of energy in one direction is known as real power. The portion of power due to stored energy,which returns to the source in each cycle,is known as reactive power. 电力拿镜广城洲量写控制四川省童点实验蜜 家电网
电力系统广域测量与控制四川省重点实验室 Concept of reactive power Power in an electric circuit is the rate of flow of energy past a given point of the circuit. In alternating current circuits, energy storage elements such as inductance and capacitance may result in periodic reversals of the direction of energy flow. The portion of power that, averaged over a complete cycle of the AC waveform, results in net transfer of energy in one direction is known as real power. The portion of power due to stored energy, which returns to the source in each cycle, is known as reactive power
Concept of reactive power The instantaneous product of voltage and current is the 0 power flow;however,only the in-phase part can be used to do work(for example 0.010.020.030.040.050.060.070.080.09 0.1 current overcome friction in a motor, voltage or heat an element) the portion of power flow that is temporarily stored in the 2 form of magnetic or electric fields,due to inductive and 0 0.010.02 0.030.040.050.060.070.080.09 0.1 Im capacitive network elements, and then returned to source, is known as reactive power. 电力集镜广城测量与控制四川省重点实脸室 家电
电力系统广域测量与控制四川省重点实验室 Concept of reactive power The instantaneous product of voltage and current is the power flow; however, only the in-phase part can be used to do work (for example overcome friction in a motor, or heat an element) the portion of power flow that is temporarily stored in the form of magnetic or electric fields, due to inductive and capacitive network elements, and then returned to source, is known as reactive power. 0 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.1 -4 -2 0 2 4 0 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.1 -4 -2 0 2 4 current voltage
Concept of reactive power The active power is used to keep the normal operation of appliances,converting electrical energy into other forms(mechanical,light or heat) Reactive power is used to exchange energy (electric field and magnetic field).It does not do work,but just help exchange the energy.Any appliances that have coils would consume reactive power. Reactive power is not useless!Motor needs to build up a magnetic field,driving mechanical movements; Transformer needs to build up magnetic field, helping induction of voltage. 电力拿镜广城洲量写控制四川省童点实验蜜 家电网
电力系统广域测量与控制四川省重点实验室 Concept of reactive power The active power is used to keep the normal operation of appliances, converting electrical energy into other forms (mechanical, light or heat) Reactive power is used to exchange energy (electric field and magnetic field). It does not do work, but just help exchange the energy. Any appliances that have coils would consume reactive power. Reactive power is not useless! Motor needs to build up a magnetic field, driving mechanical movements; Transformer needs to build up magnetic field, helping induction of voltage