Abstract:
A method for detecting an islanding operation of an inverter based distributed power source actively is provided to minimize an output disturbance without distorting an output current. A frequency variation is induced by using a reactive power. If the frequency exceeds the detection condition of an islanding operation, the islanding operation is detected. A reactive power output controller of the distributed power source outputs a reactive power component reference current command value. A frequency variation acceleration control loop(610) is added to the reactive power component reference current command value. The frequency variation is accelerated by the reactive power output or the change of the power factor.
Abstract:
A method for detecting an islanding operation of an inverter based distributed power source actively is provided to minimize an output disturbance without distorting an output current. A frequency variation is induced by using a reactive power. If the frequency exceeds the detection condition of an islanding operation, the islanding operation is detected. A reactive power output controller of the distributed power source outputs a reactive power component reference current command value. A frequency variation acceleration control loop(610) is added to the reactive power component reference current command value. The frequency variation is accelerated by the reactive power output or the change of the power factor.
Abstract:
A method and a device of independently detecting an individual operation for a microgrid are provided to continuously supply power to a major load in the microgrid in connection with a microgrid operation system. A device for independently detecting an individual operation for a microgrid includes a current detector, voltage detectors(30,31), a filter(33), a buffer(34), an A/D(Analog to Digital) conversion circuit(35), a display and operation unit(36), a signal processor(37), a memory(38), and a communication port(40). The current detector detects a current flowing on a breaker(7) and supplies the detected current to the A/D conversion circuit through the filter. The voltage detectors detect voltages on both terminals of the breaker and supplies the detected voltages to the A/D conversion circuit through the filter. The A/D conversion circuit converts a current detection signal and a voltage detection signal received from the current and voltage detectors, and supplies converted digital signals to the signal processor.
Abstract:
본 발명은 하이브리드 분산발전 시스템을 이용한 운전 제어방법에 관한 것으로서, (f) 통합감시 제어부가 직류 공통모선(A1)의 전압(Vdc)값과, 직류단 최고전압(Vdc_max) 및 최저전압(Vdc_min)을 바탕으로 제 1 분산전원부가 승압 또는 충전모드로 설정되었는지 판단하는 단계; (g) 상기 (f) 단계의 판단결과, 승압 또는 충전모드가 설정되었을 경우, 통합감시 제어부가 계수기(Cnt)를 증가시키고, 증가된 계수기의 값을 설정치와 비교하여 설정치 이상인지 여부를 판단하는 단계; (h) 상기 (g) 단계의 판단결과, 설정치 이상인 경우 즉, 일정시간이 경과한 경우, 통합감시 제어부가 계수기를 0 으로 설정하고, 승압 또는 충전모드를 실행하는 단계; (i) 상기 통합감시 제어부가 실행되는 운전이 승압모드인지 여부를 판단하는 단계; (j) 상기 (i) 단계의 판단결과, 승압모드일 경우, 통합감시 제어부가 전압기준치를 최고전압(Vdc_max) 및 최저전압(Vdc-min)의 중간 값으로 설정하는 단계; 및 (k) 상기 통합감시 제어부가 축전지의 충전상태를 검사하고 승압운전을 실행하는 단계; 로 구성된다. 하이브리드, 분산전원, 출력평준화
Abstract:
A real-time data transmission method of a power system and a system thereof are provided to reduce data processing load of a computer connected with the network by calculating, storing, and transmitting important parameters. A real-time data transmission method of a power system is composed of steps for receiving time series data from the power system; estimating parameters for the input time series data; selecting important parameters corresponding to preset conditions, from the estimated parameters, wherein the preset condition is at least one of frequency, damping ratio, time constant, and relative residue(S102,S103,S104,S105); and transmitting the selected important parameters to a server(S107). The parameter estimated for the time series data is at least one of frequency, damping coefficient, relative residue, and phase angle.
Abstract:
A device and a method for performing a system interconnection test of a renewable energy inverter are provided to perform a simulation based on a power type and a capacitance variation by changing a program coding process. A device for performing a system interconnection test of a renewable energy inverter includes an electric power simulator and an electric power amplifier(300). The electric power simulator simulates various power supply devices by using a program based on modeling and simulation processes. The electric power amplifier includes a signal implementing unit which amplifies a simulated power signal to real voltage and current waveforms, and a source voltage unit which supplies a source voltage. The electric power amplifier is connected to the electric power simulator to receive the simulated power signal and connected to a renewable energy model(100) and a system interconnection model(200). The electric power amplifier transmits the real voltage and current waveforms to an inverter.
Abstract:
본 발명은 전력변환장치를 포함하는 계통연계형 소규모 분산형 전원, 특히 태양광발전장치의 계통연계 보호 방법에 관한 것으로서, 더 구체적으로는 소규모 분산형 전원이 연계되는 계통선로에 사고가 발생하는 경우 순간적인 사고인지 영구적인 사고인지를 판별하여 계통선로의 각 사고에 대한 대응을 차별화함으로써 소규모 분산형 전원의 운전정지시간을 최소화하여 이용률을 극대화하기 위한 소규모 분산형 전원의 계통연계 보호 방법에 관한 것이다. 본 발명에 따른 분산형 전원의 계통연계 보호 방법은 상기 분산형 전원이 연계된 계통선로가 순간정전 상태인지 영구정전 상태인지를 판단하는 단계와, 상기 판단단계에서 상기 분산형 전원이 연계된 계통선로가 순간정전 상태라고 판단하는 경우 상기 분산형 전원을 대기모드로 전환하고, 영구정전 상태라고 판단하는 경우 상기 분산형 전원을 정지모드로 전환시키는 단계와, 상기 분산형 전원이 연계된 계통선로가 정상으로 복귀하였는지를 판정하여, 정상으로 복귀하였다면 상기 분산형 전원을 운전모드로 전환하는 단계를 포함한다.