静止无功系统(Static Var Systems,SVS)是静止无功补偿装置和机械投切的无功补偿装置的组合,可用于提高电力系统电压稳定性、增加系统阻尼和改善电能质量等。SVS模型的适用性直接影响仿真结果的准确性。电力系统仿真软件PSS/E中的三种SV...静止无功系统(Static Var Systems,SVS)是静止无功补偿装置和机械投切的无功补偿装置的组合,可用于提高电力系统电压稳定性、增加系统阻尼和改善电能质量等。SVS模型的适用性直接影响仿真结果的准确性。电力系统仿真软件PSS/E中的三种SVS模型具有通用性和准确性,是机电暂态仿真中模拟SVS动态特性的典型模型。本文首先讨论SVS模型在机电暂态仿真中的模拟原则,之后对PSS/E中的三种SVS模型进行分析比较。最后,通过仿真算例验证SVS的动态无功补偿作用,分析慢速电纳控制、非线性斜率控制和直接死区控制的特点。研究结果表明,控制参数选择时应兼顾响应时间、动态无功裕度和允许的电压变化范围。展开更多
针对静止无功发生器(Static Var Generator,简称SVG)在低压领域动态无功补偿中的应用,提出了一种适合单相桥式电压源型SVG的无功电流控制策略。介绍了基于这种控制策略的控制系统设计及电路实现方法,并通过实验验证了这种控制策略和控...针对静止无功发生器(Static Var Generator,简称SVG)在低压领域动态无功补偿中的应用,提出了一种适合单相桥式电压源型SVG的无功电流控制策略。介绍了基于这种控制策略的控制系统设计及电路实现方法,并通过实验验证了这种控制策略和控制系统以及电路设计的有效性和实用性。所设计的控制系统全部采用硬件电路来实现,电路具有简单、可靠、抗干扰能力强、实用及成本低廉的特点。展开更多
This paper presents the model of a SVC (Static VAR Compensator) which is controlled externally by a PI (Proportional Integral) & PD (Proportional Differential) controllers for the improvements of voltage stabil...This paper presents the model of a SVC (Static VAR Compensator) which is controlled externally by a PI (Proportional Integral) & PD (Proportional Differential) controllers for the improvements of voltage stability and damping effect of an on line power system. Both controller parameters has been optimized by using Ziegler-Nichols close loop tuning method. Both single phase and three phase (L-L) faults have been considered in the research. In this paper, a power system network is considered which is simulated in the phasor simulation method & the network is simulated in four steps; without SVC, With SVC but no externally controlled, SVC with PI controller & SVC with PD controller. Simulation result shows that without SVC, the system parameters become unstable during faults. When SVC is imposed in the network, then system parameters become stable. Again, when SVC is controlled externally by PI & PD controllers, then system parameters becomes stable in faster way then without controller. It has been observed that the SVC ratings are only 50 MVA with controllers and 200 MVA without controllers. So, SVC with PI & PD controllers are more effective to enhance the voltage stability and increases power transmission capacity of a power system. The power system oscillations are also reduced with controllers in compared to that of without controllers. So with both controllers the system performance is greatly enhanced.展开更多
As power system interconnections become more prevalent, there has been an increase in use of thyristor controlled shunt connected compensation devices for dynamic power compensation and enhancement of real power trans...As power system interconnections become more prevalent, there has been an increase in use of thyristor controlled shunt connected compensation devices for dynamic power compensation and enhancement of real power transmission capacity. In this paper, an enhancement technique of real power transfer capacity of transmission lines is presented. A SVC (static var compensator) is designed and applied to a simple power system for this purpose. Increase in power flow and improvement in bus voltage profile are observed after using the SVC. Stability analysis of the system after experiencing fault as well as consequent fault clearance by time domain analysis has also beeu performed and satisfactory results are obtained.展开更多
This paper addresses the enhancement of power system stability by simultaneous tuning of synergetic excitation damping controller and SVC (static var compensator)-based damping controllers. Each machine or generator...This paper addresses the enhancement of power system stability by simultaneous tuning of synergetic excitation damping controller and SVC (static var compensator)-based damping controllers. Each machine or generator is considered as a subsystem and its interaction with the remaining part of the system, the SVC inclusive, is modeled as a quadratic function of the active power delivered by the generator. Stable manifold is constructed for each excitation controller and based on that, an effective damping controller is derived. A lead-lag compensator is employed as a supplementary controller for the SVC. PSO (particle swarm optimization) algorithm is effectively utilized to simultaneously tune the parameters for the excitation damping controller(s) and the SVC supplementary controller. The coordination of the controllers effectively dampens the power angle oscillation and regulates the generator terminal voltage when a fault occurs. Simulation results are obtained by using the PAT (power analysis toolbox) for a SMIB (single machine infinite bus) system and a two area power system.展开更多
Power interconnections are becoming increasingly important in various parts of the world, as incentives for power exchange between countries are growing. A current example is that the Baltic Energy Market Interconnect...Power interconnections are becoming increasingly important in various parts of the world, as incentives for power exchange between countries are growing. A current example is that the Baltic Energy Market Interconnection Plan is launched by the European Council. For a variety of reasons, it is desirable to keep transmission corridors as slender as possible, i.e. keeping the number of lines as limited as possible, while still keeping adequate stability and power transmission capacity over the corridor. This is true, no matter whether it concerns a green-field project, or if it is a question of expanding an existing transmission corridor into higher power transmission capability. To achieve this, FACTS (flexible AC transmission systems), based on state of the art high power electronics, is a highly useful option, from technical, economical and environmental points of view, to increase the utilization and stability of a transmission system or intertie. The paper presents salient design features as well as benefits of recently installed FACTS devices, more specifically SVC (static var compensators) and series capacitors, for enabling or improving cross-border as well as interregional power transfer in a cost-effective and environmentally friendly way.展开更多
文摘静止无功系统(Static Var Systems,SVS)是静止无功补偿装置和机械投切的无功补偿装置的组合,可用于提高电力系统电压稳定性、增加系统阻尼和改善电能质量等。SVS模型的适用性直接影响仿真结果的准确性。电力系统仿真软件PSS/E中的三种SVS模型具有通用性和准确性,是机电暂态仿真中模拟SVS动态特性的典型模型。本文首先讨论SVS模型在机电暂态仿真中的模拟原则,之后对PSS/E中的三种SVS模型进行分析比较。最后,通过仿真算例验证SVS的动态无功补偿作用,分析慢速电纳控制、非线性斜率控制和直接死区控制的特点。研究结果表明,控制参数选择时应兼顾响应时间、动态无功裕度和允许的电压变化范围。
文摘针对静止无功发生器(Static Var Generator,简称SVG)在低压领域动态无功补偿中的应用,提出了一种适合单相桥式电压源型SVG的无功电流控制策略。介绍了基于这种控制策略的控制系统设计及电路实现方法,并通过实验验证了这种控制策略和控制系统以及电路设计的有效性和实用性。所设计的控制系统全部采用硬件电路来实现,电路具有简单、可靠、抗干扰能力强、实用及成本低廉的特点。
文摘This paper presents the model of a SVC (Static VAR Compensator) which is controlled externally by a PI (Proportional Integral) & PD (Proportional Differential) controllers for the improvements of voltage stability and damping effect of an on line power system. Both controller parameters has been optimized by using Ziegler-Nichols close loop tuning method. Both single phase and three phase (L-L) faults have been considered in the research. In this paper, a power system network is considered which is simulated in the phasor simulation method & the network is simulated in four steps; without SVC, With SVC but no externally controlled, SVC with PI controller & SVC with PD controller. Simulation result shows that without SVC, the system parameters become unstable during faults. When SVC is imposed in the network, then system parameters become stable. Again, when SVC is controlled externally by PI & PD controllers, then system parameters becomes stable in faster way then without controller. It has been observed that the SVC ratings are only 50 MVA with controllers and 200 MVA without controllers. So, SVC with PI & PD controllers are more effective to enhance the voltage stability and increases power transmission capacity of a power system. The power system oscillations are also reduced with controllers in compared to that of without controllers. So with both controllers the system performance is greatly enhanced.
文摘As power system interconnections become more prevalent, there has been an increase in use of thyristor controlled shunt connected compensation devices for dynamic power compensation and enhancement of real power transmission capacity. In this paper, an enhancement technique of real power transfer capacity of transmission lines is presented. A SVC (static var compensator) is designed and applied to a simple power system for this purpose. Increase in power flow and improvement in bus voltage profile are observed after using the SVC. Stability analysis of the system after experiencing fault as well as consequent fault clearance by time domain analysis has also beeu performed and satisfactory results are obtained.
文摘This paper addresses the enhancement of power system stability by simultaneous tuning of synergetic excitation damping controller and SVC (static var compensator)-based damping controllers. Each machine or generator is considered as a subsystem and its interaction with the remaining part of the system, the SVC inclusive, is modeled as a quadratic function of the active power delivered by the generator. Stable manifold is constructed for each excitation controller and based on that, an effective damping controller is derived. A lead-lag compensator is employed as a supplementary controller for the SVC. PSO (particle swarm optimization) algorithm is effectively utilized to simultaneously tune the parameters for the excitation damping controller(s) and the SVC supplementary controller. The coordination of the controllers effectively dampens the power angle oscillation and regulates the generator terminal voltage when a fault occurs. Simulation results are obtained by using the PAT (power analysis toolbox) for a SMIB (single machine infinite bus) system and a two area power system.
文摘Power interconnections are becoming increasingly important in various parts of the world, as incentives for power exchange between countries are growing. A current example is that the Baltic Energy Market Interconnection Plan is launched by the European Council. For a variety of reasons, it is desirable to keep transmission corridors as slender as possible, i.e. keeping the number of lines as limited as possible, while still keeping adequate stability and power transmission capacity over the corridor. This is true, no matter whether it concerns a green-field project, or if it is a question of expanding an existing transmission corridor into higher power transmission capability. To achieve this, FACTS (flexible AC transmission systems), based on state of the art high power electronics, is a highly useful option, from technical, economical and environmental points of view, to increase the utilization and stability of a transmission system or intertie. The paper presents salient design features as well as benefits of recently installed FACTS devices, more specifically SVC (static var compensators) and series capacitors, for enabling or improving cross-border as well as interregional power transfer in a cost-effective and environmentally friendly way.