A transient performance optimized CCL-LDO regulator is proposed.In the CCL-LDO,the control method of the charge pump phase-locked loop is adopted.A current control loop has the feedback signal and reference current to...A transient performance optimized CCL-LDO regulator is proposed.In the CCL-LDO,the control method of the charge pump phase-locked loop is adopted.A current control loop has the feedback signal and reference current to be compared,and then a loop filter generates the gate voltage of the power MOSFET by integrating the error current.The CCL-LDO has the optimized damping coefficient and natural resonant frequency, while its output voltage can be sub-l-V and is not restricted by the reference voltage.With a 1μF decoupling capacitor,the experimental results based on a 0.13μm CMOS process show that the output voltage is 1.0 V;when the workload changes from 100μA to 100 mA transiently,the stable dropout is 4.25 mV,the settling time is 8.2μs and the undershoot is 5.11 mV;when the workload changes from 100 mA to 100μA transiently,the stable dropout is 4.25 mV,the settling time is 23.3μs and the overshoot is 6.21 mV.The PSRR value is more than -95 dB.Most of the attributes of the CCL-LDO are improved rapidly with a FOM value of 0.0097.展开更多
目前对特高压引起的短路电流问题的研究基本仅限于500 k V网架上。通过校验发现,潍坊特高压站投产后,虽然潍坊地区500 k V站母线短路电流水平均在50 k A以内,但东部潍坊站和潍坊电厂220 k V母线短路电流将严重超标。研究上述两站短路电...目前对特高压引起的短路电流问题的研究基本仅限于500 k V网架上。通过校验发现,潍坊特高压站投产后,虽然潍坊地区500 k V站母线短路电流水平均在50 k A以内,但东部潍坊站和潍坊电厂220 k V母线短路电流将严重超标。研究上述两站短路电流控制措施已是刻不容缓。在现状运行方式的基础上,提出通过将潍坊东西电网开环运行、将潍坊站220 k V母线分段运行、将潍坊电厂至潍坊站220 k V线路移至潍坊西段母线等措施,可较好地解决潍坊站和潍坊电厂220 k V母线短路电流超标问题。稳定、潮流等相关计算结果表明,提出的短路电流控制措施可以满足电网可靠供电要求。同时,对以后的运行方式提出了相关建议。展开更多
When the power grid suffers from grid faults that cause phase disturbances,the grid-connected converter becomes destabilized by the interaction between the phase-locked loop(PLL)and the control loop.In this paper,the ...When the power grid suffers from grid faults that cause phase disturbances,the grid-connected converter becomes destabilized by the interaction between the phase-locked loop(PLL)and the control loop.In this paper,the stability of the PLL affected by the control loop under transient grid faults is studied.First,the equivalent model of the PLL under the influence of the control loop is established.Then,different response processes of PLLs under the ground fault with various control parameters are qualitatively analyzed.Furthermore,a small-signal model is proposed to assess the stability of the PLL under different control loop parameters.The system poles can be calculated to show the physical origin of the instability.Finally,simulations of a three-phase 21-level modular multilevel converter(MMC)built in PSCAD and a down-scale experiment is performed to verify the parameter influence of the control loop on the PLL.展开更多
基金Project supported by the National New Century Excellent Talents in Universitythe Program for Changjiang Scholars and Innovative Research Team in University of Chinathe National Natural Science Foundation of China(Nos.61076036,60906009)
文摘A transient performance optimized CCL-LDO regulator is proposed.In the CCL-LDO,the control method of the charge pump phase-locked loop is adopted.A current control loop has the feedback signal and reference current to be compared,and then a loop filter generates the gate voltage of the power MOSFET by integrating the error current.The CCL-LDO has the optimized damping coefficient and natural resonant frequency, while its output voltage can be sub-l-V and is not restricted by the reference voltage.With a 1μF decoupling capacitor,the experimental results based on a 0.13μm CMOS process show that the output voltage is 1.0 V;when the workload changes from 100μA to 100 mA transiently,the stable dropout is 4.25 mV,the settling time is 8.2μs and the undershoot is 5.11 mV;when the workload changes from 100 mA to 100μA transiently,the stable dropout is 4.25 mV,the settling time is 23.3μs and the overshoot is 6.21 mV.The PSRR value is more than -95 dB.Most of the attributes of the CCL-LDO are improved rapidly with a FOM value of 0.0097.
文摘目前对特高压引起的短路电流问题的研究基本仅限于500 k V网架上。通过校验发现,潍坊特高压站投产后,虽然潍坊地区500 k V站母线短路电流水平均在50 k A以内,但东部潍坊站和潍坊电厂220 k V母线短路电流将严重超标。研究上述两站短路电流控制措施已是刻不容缓。在现状运行方式的基础上,提出通过将潍坊东西电网开环运行、将潍坊站220 k V母线分段运行、将潍坊电厂至潍坊站220 k V线路移至潍坊西段母线等措施,可较好地解决潍坊站和潍坊电厂220 k V母线短路电流超标问题。稳定、潮流等相关计算结果表明,提出的短路电流控制措施可以满足电网可靠供电要求。同时,对以后的运行方式提出了相关建议。
基金This work was supported by the National Natural Science Foundation of China(51877159,51637007,U1866601).
文摘When the power grid suffers from grid faults that cause phase disturbances,the grid-connected converter becomes destabilized by the interaction between the phase-locked loop(PLL)and the control loop.In this paper,the stability of the PLL affected by the control loop under transient grid faults is studied.First,the equivalent model of the PLL under the influence of the control loop is established.Then,different response processes of PLLs under the ground fault with various control parameters are qualitatively analyzed.Furthermore,a small-signal model is proposed to assess the stability of the PLL under different control loop parameters.The system poles can be calculated to show the physical origin of the instability.Finally,simulations of a three-phase 21-level modular multilevel converter(MMC)built in PSCAD and a down-scale experiment is performed to verify the parameter influence of the control loop on the PLL.
