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41. 发明专利

JPS5666189A OVERVOLTAGE PROTECTOR FOR ELECTRIC MOTOR VARIABLE SPEED OPERATING INVERTERS 失效
公开(公告)号：JPS5666189A
公开(公告)日：1981-06-04
申请号：JP14077179
申请日：1979-10-31
申请人： FUJI ELECTRIC CO LTD
发明人： KURITA SHIGEFUMI , TOMITA HIROO
IPC分类号： H02H7/122 , H02P3/18 , H02P3/22 , H02P23/00
摘要： PURPOSE:To prevent the breakdown due to the overvoltage of a semiconductor device by temporarily interrupting inverter-frequency lowering operation for breaking when the voltage detection signal of the smoothing capacitor of an inverter has reached a fixed upper limit value. CONSTITUTION:The revolution braking of a motor 3 is performed by applying regenerative braking with a speed instruction pattern given to make a stator frequency omega1 lower than the rotor frequency omega2 by an acceleration and deceleration operator 12. The voltage detection signal of a capacitor 4 fro a voltage detector 21 and the capacitor voltages fixed upper limit value signal from a setting device 22 are compared by a comparator 23. When the capacitor voltage has exceeded a fixed upper limit value, the comparator 23 outputs signal and speed instruction value is held by the signal so that the lowering speed instruction value is interrupted. When the capacitor voltage returns to a normal range, the output signal of the comparator 23 disappears to cancell holding action so that the speed instruction value lowers to a given pattern.

42. 发明专利

JPS55141981A PULSE DURATION MODULATION TYPE INVERTER CONTROLLING DEVICE 失效
公开(公告)号：JPS55141981A
公开(公告)日：1980-11-06
申请号：JP5040979
申请日：1979-04-24
申请人： FUJI ELECTRIC CO LTD
发明人： MIKI HIROSHI , KURITA SHIGEFUMI
IPC分类号： H02M7/48 , H02M7/527
摘要： PURPOSE:To minimize a harmonic component of a motor current by changing a modulation ratio automatically according to an output frequency of an inverter. CONSTITUTION:There is provided a carrier frquency generator 7' operating independently from a frequnecy divider 6. While an output of the frequency divider 6 is such frequency as will change in direct proportion to a signal frequency of a voltage/frequency converter 5, a carrier frequency generated by the carrier frequency generator 7' is a constant frquency which is totally independent from the signal frequency to the output frequency of the frequency divider gets small when the output frequency of the frequency divider 6 is high and vice versa.

43. 发明专利

JPS55136878A INVERTER 失效
公开(公告)号：JPS55136878A
公开(公告)日：1980-10-25
申请号：JP4155179
申请日：1979-04-07
申请人： FUJI ELECTRIC CO LTD
发明人： ICHIJIYOU MASAMI , KURITA SHIGEFUMI
IPC分类号： H02M7/515
摘要： PURPOSE:To obtain high-frequency outputs having high voltages and large currents by a simple control method, by connecting a capacitor to the input side of a self- exciting inverter, and charging said capacitor from a DC power supply of a separately excited inverter. CONSTITUTION:A capacitor 16 is connected to the DC input side of a voltage-type three-phase self-exciting inverter 10. While a DC power supply 22, whose voltage can be adjusted, and a reactor 24 are serially connected to the input side of a current-type three-phase separately excited inverter 18. Then, the outputs of the inverters 10 and 18 are connected by a coupling reactor 26, and a load 28 is connected to the output terminal of the inverter 10. Therefore, the capacitor 16 charged by the DC power supply 22 of the separately excited inverter 18 via the self-exciting inverter 10 at the time of starting, and a specified reverse-bias voltage for commutation can be supplied to the separately excited inverter 18, thereby the number of parts can be reduced, and the high-frequency outputs having high voltages and large currents can be obtained.

44. 发明专利

JPS54152954A PARALLEL CONNECTION CIRCUIT OF TRANSISTOR 失效
公开(公告)号：JPS54152954A
公开(公告)日：1979-12-01
申请号：JP6190578
申请日：1978-05-24
申请人： FUJI ELECTRIC CO LTD
发明人： SAWA KUNIHIKO , KURITA SHIGEFUMI
IPC分类号： H03K17/12
摘要： PURPOSE:To reduce the capacity of a base driver circuit and also to eliminate the need for a current balancing transformer by driving several single transistors connected in parallel by a common Darlington transistor. CONSTITUTION:To single transistors TrTi1 to TrTin connected in parallel, Darlington TrTB is connected which flows base currents, and TrTB is also connected to base driver circuit B. In the above-mentioned constitution, saturation characteristics and switching characteristics of TrTi1 to TrTin are easy to become uniform in comparison with those of Darlington transistor TB and since their bases are connected to common TrTB, so that current balance will be extremely excellent. Further, TrTB is used for the base driver circuit, so that the circuit will require only a small current.

45. 发明专利

JPS5318375A TRANSISTOR BASE DRIVING CIRCUIT 失效
公开(公告)号：JPS5318375A
公开(公告)日：1978-02-20
申请号：JP9291576
申请日：1976-08-04
申请人： FUJI ELECTRIC CO LTD
发明人： KURITA SHIGEFUMI , ICHIJIYOU MASAMI
IPC分类号： H03K17/04
摘要： PURPOSE:Switching characteristics are improved by always supplying a certain fixed base reverse bias voltage irrespective of the amplitude and frequency of ON-signals.

46. 发明专利

JPS5316831A CONTROL METHOD FOR INVERTER 失效
公开(公告)号：JPS5316831A
公开(公告)日：1978-02-16
申请号：JP9166576
申请日：1976-07-30
申请人： FUJI ELECTRIC CO LTD
发明人： KURITA SHIGEFUMI , MIKI HIROSHI
IPC分类号： H02M7/521 , H02M7/48 , H02M7/515
摘要： PURPOSE:To vary output voltage of inverter in proportion with basic frequency of inverter.

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