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1. 发明专利

JPH044755A SELF-EXCITED CONVERTER USING NORMALLY ON THYRISTOR 失效
公开(公告)号：JPH044755A
公开(公告)日：1992-01-09
申请号：JP10454190
申请日：1990-04-20
申请人： HITACHI LTD , TOKYO ELECTRIC POWER CO
发明人： WAKASUGI KENJI , KAWAI TADAO , TOKIWA YUKIO , ICHIKAWA FUMITOSHI
IPC分类号： H02H7/12 , H02M7/12 , H02M7/155 , H02M7/162
摘要： PURPOSE:To surely prevent short-circuiting of a normally ON thyristor at the time of starting conversion to enable applying the normally ON thyristor to an AC/DC converter, especially to a high-voltage-converter by turning OFF only a series switch prior to operating a breaker through adding the switch to the arm of the normally ON thyristor. CONSTITUTION:At the time of starting conversion, all switches 7 are turned OFF and then a breaker 1 is closed. In this case, electric current does not flow through the arm of normally ON thyristors 2. In gate pulse amplifiers 3, power is established by the current flowing through diodes 4 to control all normally ON thyristors 2 to OFF, immediately after the breaker 1 is closed. Accordingly, AC voltage is applied to both ends of each normally ON thyristor 2 and a converter is placed in a starting state. Because the power supply of the gate pulse amplifiers 3 is a charging type, the switching operation of the switch 7 is unnecessary after the gate power supply has been once established so that a normal operation as AC/DC converter is made possible.

2. 发明专利

JPH04334926A PROTECTION APPARATUS OF SYNCHRONOUS PHASE MODIFIER 失效
公开(公告)号：JPH04334926A
公开(公告)日：1992-11-24
申请号：JP10745691
申请日：1991-05-13
申请人： HITACHI LTD
发明人： WAKASUGI KENJI , NAKAMURA TOMOHARU
IPC分类号： H02H3/16 , H02H7/06
摘要： PURPOSE:To protect various devices and apparatuses in each circuit section from an accident even if a synchronous phase modifier is driven by connecting an output transformer as a voltage booster in the output side of a power converter. CONSTITUTION:An apparatus connects a synchronous phase modifier 10 to a main circuit 14 and also connects it to a power system 2, different from the main circuit 14 and provides, in the grounding line 38 of the synchronous phase modifier 10, first accident detecting means 40, 42 for detecting an accident from an electrical signal flowing through the grounding line 38. An output transformer 28 as a voltage booster is provided between the synchronous phase modifier 10 and power converter 20. Second accident detecting means 46, 48 for detecting an accident from an electrical signal flowing into the grounding line 44 is provided in that grounding line 44 of the output transformer 28, a circuit section connecting the power system 24 and the synchronous phase modifier 10 is divided into two grounding sections and an accident in each grounding section is protected by the first accident detecting means 40, 42 and second accident detecting means 46, 48.

3. 发明专利

JPH0635556A CONTROLLER FOR SYNCHRONOUS ROTARY PHASE MODIFIER 失效
公开(公告)号：JPH0635556A
公开(公告)日：1994-02-10
申请号：JP19370292
申请日：1992-07-21
申请人： HITACHI LTD
发明人： WADA YOSHIHARU , NAKAMURA TOMOHARU , WAKASUGI KENJI
IPC分类号： G05F1/70 , H02J3/18
摘要： PURPOSE:To prevent the operation of a limiter and to effectively display a constant voltage control function by changing the voltage of an output terminal in accordance with the deviation of the float set value being the reference operation value. CONSTITUTION:A controller 5 detects the current and the voltage of a system by the detectors 10 and 13 by use of the detection signals of a current transformer 12 and a transformer 6 connected to a system. Then the controller 5 calculates the wattless power Q generated by a rotary phase modifier RC and compares this value with the set value Qref of the wattless power Q to obtain the deviation DELTAQ. The deviation DELTAQ given from a subtractor 15 is integrated by an integrator 16, and the integrated value Vf being the integration output is subtracted from a target voltage setter 11. Then the target voltage value is changed based on the deviation of the wattless power generated by the RC. Thus it is possible to cope with the up-down change of a stable point and to control to avoid the operation of a limiter.

4. 发明专利

JPH04121024A POWER FLUCTUATION CONTROL METHOD AND DEVICE 失效
公开(公告)号：JPH04121024A
公开(公告)日：1992-04-22
申请号：JP24028590
申请日：1990-09-11
申请人： HITACHI LTD
发明人： NAKAMURA TOMOHARU , GOTO MASUO , WAKASUGI KENJI
IPC分类号： H02J3/24 , H02J3/26
摘要： PURPOSE:To prevent the reverse operation by the change in the direction of power transmission line power current by inputting the absolute value of the power transmission line power current P in the power fluctuation control method using a static invalid power compensator, which controls the voltage of the system and controls the fluctuation of generator output. CONSTITUTION:The detected power current P is made into an absolute value with a block 1 for making it into an absolute value, and is made the shape of not being subject to the influence of polarity, subsequently, the change distribution P of P is detected with a P detection block 2. The detected P is input into a P control block 3 so as to get 90 deg. advance phase output. To this 90 deg. advance phase output, in a multiplier 8, power fluctuation control gain Mp is applied. On the other hand, system voltage is detected, and is input into a multiplier 1, and gain Mv is applied. The outputs of the multipliers 7 and 8 are added in an adder 9, and the output is used as the control output of a power fluctuation controller.

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