RELAY PROTECTION METHOD AND DEVICE AGAINST LC PARALLEL CIRCUIT DETUNING FAULTS
    1.
    发明公开
    RELAY PROTECTION METHOD AND DEVICE AGAINST LC PARALLEL CIRCUIT DETUNING FAULTS 审中-公开
    VARRICHTUNG GEGEN PARALLELE的相关资料LC-SCHALTVERSTIMMMUNGSFEHLER

    公开(公告)号:EP3139462A1

    公开(公告)日:2017-03-08

    申请号:EP15785909.1

    申请日:2015-01-08

    IPC分类号: H02H7/22

    摘要: A relay protection method against LC parallel circuit detuning faults comprises the steps of: a relay protection device samples a current of a parallel LC, that is, a reactor and a capacitor, and samples a total current flowing through the whole LC; convert the current of the reactor into a current of an equivalent capacitor; calculate amplitudes of the current of the equivalent capacitor and a current of a realistic capacitor and calculate an amplitude of the total current flowing through the LC; calculate a current amplitude ratio of the equivalent capacitor to the realistic capacitor; and when the amplitude of the total current flowing through the LC is large enough, send an alarm signal or a trip after a setting time delay if the current ratio exceeds a preset upper and lower limit range. Also provided is a corresponding relay protection device. The relay protection method and device against LC parallel circuit detuning faults can improve stability of calculation results of a current ratio and raise sensitivity and rapidity of protection.

    摘要翻译: 一种针对LC并联电路失谐故障的继电保护方法,包括以下步骤:继电保护装置对并联LC的电流,即电抗器和电容器进行采样,并对流过整个LC的总电流进行采样; 将电抗器的电流转换为等效电容器的电流; 计算等效电容器的电流的幅度和实际电容器的电流,并计算流过LC的总电流的幅度; 计算等效电容器与实际电容器的电流幅度比; 并且当流过LC的总电流的幅度足够大时,如果电流比超过预设的上下限范围,则在设定时间延迟之后发送报警信号或跳闸。 还提供了相应的继电保护装置。 针对LC并联电路失谐故障的继电保护方法和装置可以提高电流比的计算结果的稳定性,提高灵敏度和快速保护。

    METHOD AND APPARATUS FOR IDENTIFYING OPEN PHASE OF CIRCUIT BREAKER ON BASIS OF VOLTAGE
    4.
    发明公开
    METHOD AND APPARATUS FOR IDENTIFYING OPEN PHASE OF CIRCUIT BREAKER ON BASIS OF VOLTAGE 审中-公开
    用于根据电压识别断路器的开路相位的方法和设备

    公开(公告)号:EP3291401A1

    公开(公告)日:2018-03-07

    申请号:EP16785743.2

    申请日:2016-02-19

    IPC分类号: H02H7/22

    摘要: A method and apparatus for identifying an open phase of a circuit breaker on the basis of voltage. The method comprises: a protection apparatus measures three-phase voltages (Ua, Ub, Uc, UA, UB, UC) at two sides (M, N) of a circuit breaker (B); respectively calculates a vector difference and an effective value of the voltages at two sides of the circuit breaker; when the phase voltages at two sides are both greater than 80% to 90% of a rated voltage, and the voltage vector difference at two sides of the one-phase or two-phase circuit breaker is greater than a set voltage, it is determined that the circuit breaker has an open phase; and actuates an alarming or tripping operation after a short time delay t. The method and the corresponding apparatus can solve the problem of the failure in recognizing an open phase by a traditional negative-sequence current criterion when a circuit breaker has an open phase in the case of light load; and moreover, three-phase inconsistent contact is not needed, and the method and apparatus are also suitable for a three-phase linked circuit breaker.

    摘要翻译: 一种基于电压识别断路器断相的方法和装置。 该方法包括:保护装置测量断路器(B)的两侧(M,N)处的三相电压(Ua,Ub,Uc,UA,UB,UC); 分别计算断路器两侧电压的矢量差和有效值; 当两侧的相电压均大于额定电压的80%至90%,并且单相或两相断路器两侧的电压矢量差大于设定电压时, 断路器具有断相; 并在短时间延迟t后启动报警或跳闸操作。 该方法及相应装置可解决在轻载情况下断路器为断相时,传统负序电流判据识别断相失败的问题; 而且不需要三相不一致触点,该方法和装置也适用于三相联动断路器。

    OPTICAL CT-BASED STARTING STANDBY TRANSFORMER OPEN-PHASE DETECTION METHOD

    公开(公告)号:EP3703210A1

    公开(公告)日:2020-09-02

    申请号:EP18905615.3

    申请日:2018-05-02

    IPC分类号: H02H7/04

    摘要: The present invention discloses a method for detecting open phase of a startup/standby transformer based on optical CT. A startup/standby transformer in a power plant is in a no-load condition for a long time as a standby power supply. Once a single-phase open phase fault occurs, there is no significant change in the voltage phasor and voltage sequence component of each side. If not found in time, the defect may pose a great threat to the safe operation of the power plant. In the present invention, the optical CT is used to detect a three-phase current of the high-voltage side of the startup/standby transformer. If the current satisfies an open phase criterion, it is determined that an open phase fault occurs, and then, an alarm signal is given after a delay and an operator is informed to handle the fault in time. Therefore, the operation reliability of the startup/standby transformer system in the power plant is enhanced.

    FREQUENCY-CONVERSION DIFFERENTIAL PROTECTION METHOD FOR OUTPUT TRANSFORMER OF STATIC FREQUENCY CONVERTOR SYSTEM
    7.
    发明公开
    FREQUENCY-CONVERSION DIFFERENTIAL PROTECTION METHOD FOR OUTPUT TRANSFORMER OF STATIC FREQUENCY CONVERTOR SYSTEM 审中-公开
    VERFAHRENFÜRFREQUENZWANDLUNGSDIFFERENZIALSCHUTZFÜRAUSGANGSTRANSFORMATOR EINES STATISCHEN FREQUENZWANDLERSYSTEMS

    公开(公告)号:EP2897243A1

    公开(公告)日:2015-07-22

    申请号:EP13837802.1

    申请日:2013-07-01

    IPC分类号: H02H7/045

    CPC分类号: H02H7/045

    摘要: In a frequency-conversion differential protection method for an output transformer of a static frequency converter (SFC) system, a protection device measures the three-phase current on each side of the output transformer of the SFC system; according to the connection manner of the output transformer, triangle side is used as a reference to perform phase correction on the star side; at the same time, in consideration of the secondary rated current on each side of the transformer are different, a balance coefficient on each side is adjusted, to calculate sampling values of correcting current on each side and the differential current; a generatorstart-up and shutdown protection algorithm which unaffected by frequency is used to calculate amplitude values of the correcting current, the differential current, and the restraint current; and frequency-conversion differential protection for the output transformer is implemented by using biased differential characteristic and according to magnitudes of the differential current and the restraint current. The protection method adapts to a large-scale frequency change, and compared with instantaneous overcurrent protection, greatly improves the sensitivity of detection on an internal fault of the output transformer.

    摘要翻译: 在静态变频器(SFC)系统的输出变压器的变频差动保护方法中,保护装置测量SFC系统输出变压器两侧的三相电流; 根据输出变压器的连接方式,三角侧作为参考,在星形侧执行相位校正; 同时,考虑到变压器两侧的二次额定电流不同,调整每侧的平衡系数,计算出每侧校正电流的采样值和差动电流; 不受频率影响的发电机起动和停机保护算法用于计算校正电流,差动电流和约束电流的振幅值; 并且通过使用偏置差分特性并根据差分电流和约束电流的大小来实现输出变压器的变频差动保护。 保护方式适应大规模变频,与瞬时过流保护相比,大大提高了输出变压器内部故障检测灵敏度。

    PROTECTION METHOD, APPARATUS AND SYSTEM FOR PSEUDO-BIPOLAR DIRECT-CURRENT POWER DISTRIBUTION NETWORK, AND DEVICE AND MEDIUM

    公开(公告)号:EP4016778A1

    公开(公告)日:2022-06-22

    申请号:EP20852658.2

    申请日:2020-03-17

    IPC分类号: H02H7/26 H02H3/26 G01R19/10

    摘要: The present application provides a protection method, apparatus and system for a pseudo-bipolar direct-current power distribution network, and a device and a medium. The method comprises: detecting a transverse differential current value of a first direct-current switch of the pseudo-bipolar direct-current power distribution network, the transverse differential current value being an absolute value of a difference between a positive pole current amplitude and a negative pole current amplitude of the first direct-current switch; generating first transverse differential out-of-limit signals in response to a condition of the transverse differential current value being greater than a preset transverse differential out-of-limit threshold; detecting second transverse differential out-of-limit signals of a subordinate direct-current switch of the first direct-current switch; and determining that the fault of the first direct-current switch is an internal fault in response to a condition that the first transverse differential out-of-limit signals have been generated and the second transverse differential out-of-limit signals of the subordinate direct-current switch of the first direct-current switch are not found, and performing fault protection.

    DIFFERENTIAL PROTECTION METHOD FOR CURRENT SOURCE CONVERTER, AND RELAY PROTECTION DEVICE
    9.
    发明公开
    DIFFERENTIAL PROTECTION METHOD FOR CURRENT SOURCE CONVERTER, AND RELAY PROTECTION DEVICE 审中-公开
    差动保护方法及继电器STROMQUELLENUMRICHTER GUARD

    公开(公告)号:EP3007294A1

    公开(公告)日:2016-04-13

    申请号:EP14804991.9

    申请日:2014-04-14

    IPC分类号: H02H7/26

    摘要: Embodiments of the present invention disclose a differential protection method for current source converter, including: sampling, by a relay protection device, secondary side currents of current transformers on two sides of a protected current source converter, to obtain incomer-side three-phase currents, and outgoer-side three-phase currents; rectifying the incomer-side three-phase currents and the outgoer-side three-phase currents, to obtain an incomer-side input current and an outgoer-side output current which are equivalent; converting the incomer-side input current and the outgoer-side output current according to a current ratio of the current transformers on the two sides, to acquire a transient differential current and a transient restraint current; acquiring a differential current and a restraint current according to the transient differential current and the transient restraint current; and achieving differential protection according to the differential current and the restraint current. The embodiments of the present invention further disclose a relay protection device correspondingly.