A novel control strategy for three-phase shunt active power filter (SAPF) was proposed to improve its performance under non-ideal mains voltages. The approach was inspired by our finding that the classic instantaneous...A novel control strategy for three-phase shunt active power filter (SAPF) was proposed to improve its performance under non-ideal mains voltages. The approach was inspired by our finding that the classic instantaneous reactive power theory based algorithm was unsatisfactory in terms of isolating positive sequence fundamental active components exactly under non-ideal mains voltages. So, a modified ip-iq reference current calculation method was presented. With usage of the new method, not only the positive sequence but also the fundamental active current components can be accurately isolated from load current. A deadbeat closed-loop control model is built in order to eliminate both delay error and tracking error between reference voltages and compensation voltages under unbalanced and distorted mains voltages. Computer simulation results show that the proposed strategy is effective with better tracking ability and lower total harmonic distortion (THD). The strategy is also applied to a 10 kV substation with a local electrolysis manganese plant injecting a large amount of harmonics into the power system, and is proved to be more practical and efficient.展开更多
For multiple grid-connected inverters with active filter function,it makes sense to regulate every unit to output maximum active power from photovoltaic arrays,as well as eliminate the harmonic due to the non-linear l...For multiple grid-connected inverters with active filter function,it makes sense to regulate every unit to output maximum active power from photovoltaic arrays,as well as eliminate the harmonic due to the non-linear loads connected to the electric networks.Naturally,a centralized control coordination strategy was proposed for the purpose of high facility utilization,good harmonic compensation ability and unwanted overcompensation condition.Based on a vector decoupling control scheme and generalized instantaneous reactive power theory,the solution was to allocate the harmonic eliminating task for every inverter according to the instantaneous power margin of each.The grid current always keeps sinusoidal in spite of non-linear load change and output active power change for any inverter.The simulation results validate the efficacy of the proposed coordination strategy.展开更多
In this paper, a multiplexing technique is applied on a neural harmonics extraction method, based on an efficient formulation of the instantaneous reactive power theory. This approach can be used in nonlinear loads co...In this paper, a multiplexing technique is applied on a neural harmonics extraction method, based on an efficient formulation of the instantaneous reactive power theory. This approach can be used in nonlinear loads compensation with APFs （Active Power Filters）. The architecture for reference current generation, synchronized by a neural phase lock-loop, is composed of three Adaline neural networks. This leads to an important consumption of field programmable gate array resources during implementation. The proposed technique uses only one Adaline and keeps the immunity of the approach under non-sinusoidal and unbalanced conditions of voltage. Simulation results of the neural harmonics detection system connected to a reference current controller show balanced and sinusoidal source currents under various conditions. Results with experimental measurement made on an APF test bench demonstrate its good performances on harmonics filtering. Moreover, the simplified structure from the new approach called mp-q method shows a significant resource reduction.展开更多
基金Project(JC200903180555A) supported by Shenzhen City Science and Technology Plan, China
文摘A novel control strategy for three-phase shunt active power filter (SAPF) was proposed to improve its performance under non-ideal mains voltages. The approach was inspired by our finding that the classic instantaneous reactive power theory based algorithm was unsatisfactory in terms of isolating positive sequence fundamental active components exactly under non-ideal mains voltages. So, a modified ip-iq reference current calculation method was presented. With usage of the new method, not only the positive sequence but also the fundamental active current components can be accurately isolated from load current. A deadbeat closed-loop control model is built in order to eliminate both delay error and tracking error between reference voltages and compensation voltages under unbalanced and distorted mains voltages. Computer simulation results show that the proposed strategy is effective with better tracking ability and lower total harmonic distortion (THD). The strategy is also applied to a 10 kV substation with a local electrolysis manganese plant injecting a large amount of harmonics into the power system, and is proved to be more practical and efficient.
基金Project(51107111)supported by the National Natural Science Foundation of China
文摘For multiple grid-connected inverters with active filter function,it makes sense to regulate every unit to output maximum active power from photovoltaic arrays,as well as eliminate the harmonic due to the non-linear loads connected to the electric networks.Naturally,a centralized control coordination strategy was proposed for the purpose of high facility utilization,good harmonic compensation ability and unwanted overcompensation condition.Based on a vector decoupling control scheme and generalized instantaneous reactive power theory,the solution was to allocate the harmonic eliminating task for every inverter according to the instantaneous power margin of each.The grid current always keeps sinusoidal in spite of non-linear load change and output active power change for any inverter.The simulation results validate the efficacy of the proposed coordination strategy.
文摘In this paper, a multiplexing technique is applied on a neural harmonics extraction method, based on an efficient formulation of the instantaneous reactive power theory. This approach can be used in nonlinear loads compensation with APFs （Active Power Filters）. The architecture for reference current generation, synchronized by a neural phase lock-loop, is composed of three Adaline neural networks. This leads to an important consumption of field programmable gate array resources during implementation. The proposed technique uses only one Adaline and keeps the immunity of the approach under non-sinusoidal and unbalanced conditions of voltage. Simulation results of the neural harmonics detection system connected to a reference current controller show balanced and sinusoidal source currents under various conditions. Results with experimental measurement made on an APF test bench demonstrate its good performances on harmonics filtering. Moreover, the simplified structure from the new approach called mp-q method shows a significant resource reduction.
