特高压交流输电系统工频过电压差异性研究

发布时间：2018-11-26 19:23

【摘要】：根据特高压电网特点,综合考虑系统结构、电源容量、输电潮流、线路参数、高抗补偿、串联补偿及线路开关站等诸多因素,研究了特高压交流输电系统工频过电压差异性。研究结果表明:单回、同塔双回及单/双回混合3种架设方式的线路,单相接地甩负荷时变电站线路侧工频过电压存在差异,同塔双回架设时过电压水平最低,单/双回混合架设时过电压水平与混合比例有关。厂对网特高压同塔双回输电系统送电距离在300 km以内,变电站母线侧和线路侧工频过电压水平一般不超1.2 pu和1.3 pu;300?600 km内,过电压水平一般不超1.3 pu和1.5 pu。网对网特高压同塔双回输电系统过电压水平一般比厂对网结构要低,送电距离在400 km以内,母线侧和线路侧工频过电压水平一般不超1.2 pu和1.3 pu;400?600 km内,过电压水平一般不超1.2 pu和1.4 pu。线路加装串补后的工频过电压水平与无串补时基本相当。线路中间设立开关站的特高压同塔双回线路,前、后两段线路不对称的运行方式下,单相接地甩负荷工频过电压问题突出。建议采取全线单回的运行方式,以避免此类方式的出现。
[Abstract]:According to the characteristics of UHV power network, considering the system structure, power capacity, transmission power flow, line parameters, high resistance compensation, series compensation and line switching station, the difference of power frequency overvoltage in UHV AC transmission system is studied. The results show that the power frequency overvoltage of substation side is different when single circuit, same tower and double circuit and single / one double circuit are mixed, and the level of overvoltage is the lowest when the same tower is set up with double circuit, and the power frequency overvoltage of substation is different when single phase grounding and load rejection. The overvoltage level is related to the mixing ratio. The power transmission distance of the UHV dual circuit transmission system is less than 300 km, and the power frequency overvoltage level on the bus side and the line side of the substation generally does not exceed 1.2 pu and 1.3 pu;. Overvoltage levels generally not exceeding 1.3 pu and 1.5 pu. within 300,600 km The overvoltage level of UHV double-circuit transmission system is generally lower than that of power supply network, the power transmission distance is less than 400 km, and the power frequency overvoltage level of bus side and line side is less than 1.2 pu and 1.3 pu;. Overvoltage levels generally not exceeding 1.2 pu and 1.4 pu. within 400,600 km The power frequency overvoltage level after the line is installed with series compensation is basically the same as that without series compensation. The UHV double-circuit line with the same tower is set up in the middle of the line. Under the asymmetrical operation mode of the former and the latter two sections of the line, the power frequency overvoltage problem of single-phase earthing load rejection is prominent. It is recommended that the whole line single-cycle operation mode be adopted to avoid the appearance of this kind of way.
【作者单位】：中国电力科学研究院;国家电网公司;国网电力科学研究院;
【分类号】：TM721.2

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