Renewable generation interfaced through gridforming converters are proposed as a replacement for synchronous generators in power systems.However,compared to the synchronous generator,the power electronics converter ha...Renewable generation interfaced through gridforming converters are proposed as a replacement for synchronous generators in power systems.However,compared to the synchronous generator,the power electronics converter has a strict limit on the current to avoid overcurrent damage.The gridforming converter acts like a voltage source,directily controlling the voltage.This conflicts with the operation of the conventional current limit control,which is applied to a current source.The switch between the voltage control and current control aimed to impose the current limit leads to synchronization instability.This paper proposes a novel control scheme which can be applied to the grid forming voltage control in order to enforce current limits.The proposed method has been verified through simulation and hardware tests in both symmetrical and asymmetrical faults to perform current suppression while maintaining synchronization stability in the voltage control mode.展开更多
To achieve a constant current limit,low power consumption and high driving capability,a micro-power LDO with a piecewise voltage-foldback current-limit circuit is presented.The current-limit threshold is dynamically a...To achieve a constant current limit,low power consumption and high driving capability,a micro-power LDO with a piecewise voltage-foldback current-limit circuit is presented.The current-limit threshold is dynamically adjusted to achieve a maximum driving capability and lower quiescent current of only 300 nA.To increase the loop stability of the proposed LDO,a high impedance transconductance buffer under a micro quiescent current is designed for splitting the pole that exists at the gate of the pass transistor to the dominant pole,and a zero is designed for the purpose of the second pole phase compensation.The proposed LDO is fabricated in a BiCMOS process. The measurement results show that the short-circuit current of the LDO is 190 mA,the constant limit current under a high drop-out voltage is 440 mA,and the maximum load current under a low drop-out voltage is up to 800 mA. In addition,the quiescent current of the LDO is only 7μA,the load regulation is about 0.56%on full scale,the line regulation is about 0.012%/V,the PSRR at 120 Hz is 58 dB and the drop-out voltage is only 70 mV when the load current is 250 mA.展开更多
基金This work was supported in part by the Science Foundation Ireland(SFI)under Grant SFI/15/SPP/E3125。
文摘Renewable generation interfaced through gridforming converters are proposed as a replacement for synchronous generators in power systems.However,compared to the synchronous generator,the power electronics converter has a strict limit on the current to avoid overcurrent damage.The gridforming converter acts like a voltage source,directily controlling the voltage.This conflicts with the operation of the conventional current limit control,which is applied to a current source.The switch between the voltage control and current control aimed to impose the current limit leads to synchronization instability.This paper proposes a novel control scheme which can be applied to the grid forming voltage control in order to enforce current limits.The proposed method has been verified through simulation and hardware tests in both symmetrical and asymmetrical faults to perform current suppression while maintaining synchronization stability in the voltage control mode.
基金supported by the Ministerial "12th Five-Year" Pre-Research Fund of China(No.413080203)
文摘To achieve a constant current limit,low power consumption and high driving capability,a micro-power LDO with a piecewise voltage-foldback current-limit circuit is presented.The current-limit threshold is dynamically adjusted to achieve a maximum driving capability and lower quiescent current of only 300 nA.To increase the loop stability of the proposed LDO,a high impedance transconductance buffer under a micro quiescent current is designed for splitting the pole that exists at the gate of the pass transistor to the dominant pole,and a zero is designed for the purpose of the second pole phase compensation.The proposed LDO is fabricated in a BiCMOS process. The measurement results show that the short-circuit current of the LDO is 190 mA,the constant limit current under a high drop-out voltage is 440 mA,and the maximum load current under a low drop-out voltage is up to 800 mA. In addition,the quiescent current of the LDO is only 7μA,the load regulation is about 0.56%on full scale,the line regulation is about 0.012%/V,the PSRR at 120 Hz is 58 dB and the drop-out voltage is only 70 mV when the load current is 250 mA.
