JPH0368640B2 - - Google Patents
Info
- Publication number
- JPH0368640B2 JPH0368640B2 JP60007706A JP770685A JPH0368640B2 JP H0368640 B2 JPH0368640 B2 JP H0368640B2 JP 60007706 A JP60007706 A JP 60007706A JP 770685 A JP770685 A JP 770685A JP H0368640 B2 JPH0368640 B2 JP H0368640B2
- Authority
- JP
- Japan
- Prior art keywords
- power supply
- switching
- motor
- power source
- power
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P25/00—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details
- H02P25/16—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details characterised by the circuit arrangement or by the kind of wiring
- H02P25/18—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details characterised by the circuit arrangement or by the kind of wiring with arrangements for switching the windings, e.g. with mechanical switches or relays
- H02P25/20—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details characterised by the circuit arrangement or by the kind of wiring with arrangements for switching the windings, e.g. with mechanical switches or relays for pole-changing
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/08—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric motors
- H02H7/085—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric motors against excessive load
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Control Of Ac Motors In General (AREA)
Description
【発明の詳細な説明】
〔発明の技術分野〕
この発明は、可変周波数電源（以下Ｖ電源と略
称する）又は商用電源（以下Ｃ電源と略称する）
のいずれかを択一的に選択して電動機を駆動する
電源切替装置に関するものであり、特に電源切替
時に発生する電動機の過熱を防止して安全に運転
する技術に関するものである。[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a variable frequency power supply (hereinafter abbreviated as V power supply) or a commercial power supply (hereinafter abbreviated as C power supply).
The present invention relates to a power supply switching device that selectively selects one of the following to drive a motor, and particularly relates to a technique for safely operating the motor by preventing overheating of the motor that occurs when switching the power supply.
第１図は、可変周波数(V)電源システムを説明す
る図であり、図において、１は商用(C)電源、２は
Ｖ電源、３，４，５は開閉器、６はＣ電源１又は
Ｖ電源２により駆動される電動機、７は電動機６
に直結された回転体（フアン）、８は流体路、８
ａ，８ｂは流体路８のそれぞれ入口、出口、９は
流体路８を通過する流体量の制御をする機械的制
御機構（入口ベーン）１０は流体制御装置、１１
は流体制御装置１０への制御入力、１０ａ及び１
０ｂはＶ電源２及び機械的制御機構９にそれぞれ
制御信号を送る信号線、１２は電力検出器であ
る。
FIG. 1 is a diagram explaining a variable frequency (V) power supply system. In the figure, 1 is a commercial (C) power supply, 2 is a V power supply, 3, 4, and 5 are switches, and 6 is a C power supply 1 or Electric motor driven by V power source 2, 7 is electric motor 6
A rotating body (fan) directly connected to a fluid path, 8
a, 8b are the inlet and outlet of the fluid path 8, 9 is a mechanical control mechanism (inlet vane) that controls the amount of fluid passing through the fluid path 8; 10 is a fluid control device;
are the control inputs to the fluid control device 10, 10a and 1
0b is a signal line that sends control signals to the V power source 2 and the mechanical control mechanism 9, respectively, and 12 is a power detector.
第２図は、従来の制御回路図であり、図におい
て、BP，BNは制御電源の＋，−母線、１２ａ，
１２ｂは電力検出器１２が所定値以上の電力を検
出したとき、それぞれ閉、開となる接点１３ａ，
１３ｂは電力検出器１２以外の電源切替条件を与
える条件リレー（図示せず）のそれぞれ動作時
閉、開となる接点、３Ｔ，５Ｔはそれぞれ開閉器
３，５のトリツプコイル、３Ｃ，５Ｃはそれぞれ
開閉器３，５の投入コイル、５ａ，５ｂは開閉器
５が閉のときそれぞれ閉、開となる接点、３ａ，
３ｂは開閉器３が閉のとき、それぞれ閉、開とな
る接点、T1，T2はタイマー、T1a，T2aはそれぞ
れタイマーT1，T2の接点である。 FIG. 2 is a conventional control circuit diagram. In the figure, BP and BN are + and - bus bars of the control power supply, 12a,
12b is a contact 13a that closes and opens, respectively, when the power detector 12 detects power equal to or higher than a predetermined value.
13b is a contact that closes or opens during operation of a condition relay (not shown) that provides power switching conditions other than the power detector 12, 3T and 5T are trip coils of switches 3 and 5, respectively, and 3C and 5C are open and close contacts, respectively. The closing coils of the switches 3 and 5, 5a and 5b are contacts that close and open, respectively, when the switch 5 is closed.
3b is a contact that closes and opens, respectively, when the switch 3 is closed; T 1 and T 2 are timer contacts; and T 1 a and T 2 a are contacts for timers T 1 and T 2 , respectively.
なお、開閉器５を開、開閉器３を閉とする手段
を第１の開閉手段、開閉器３を開、開閉器５を閉
とする手段を第２の開閉手段と呼ぶこととする。 Note that the means for opening the switch 5 and closing the switch 3 will be called a first switching means, and the means for opening the switch 3 and closing the switch 5 will be called a second switching means.
次に動作について説明する。説明をわかりやす
くするために、第１図を発電プラントのボイラ用
フアンの例として説明する。この時、回転体７は
フアンであり、機械的制御機構９は入口ベーン、
流体路８は風路である。 Next, the operation will be explained. To make the explanation easier to understand, FIG. 1 will be explained as an example of a boiler fan for a power generation plant. At this time, the rotating body 7 is a fan, and the mechanical control mechanism 9 is an inlet vane,
The fluid path 8 is an air path.
Ｖ電源２の運転時は、開閉器４，５閉、開閉器
３開となつており、電動機６はＶ電源２で駆動さ
れる。Ｖ電源２の出力は、周波数(F)が可変となつ
ており、従つて電動機６の回転数(N)は
Ｎ＝120／Ｐ×Ｆ ……（式１）
Ｐ：電動機６の極数
となり、周波数(F)によつて電動機６は可変速運転
される。 When the V power supply 2 is in operation, the switches 4 and 5 are closed and the switch 3 is open, and the electric motor 6 is driven by the V power supply 2. The output of the V power supply 2 has a variable frequency (F), so the number of revolutions (N) of the motor 6 is N=120/P×F...(Formula 1) P: Number of poles of the motor 6 , the electric motor 6 is operated at variable speed depending on the frequency (F).
また、電動機６の電圧EM（即ちＶ電源２の出力
電圧）は電動機６の鉄心飽和を避けるために
EM／Ｆ＝Ｋ ……（式２）
Ｋ：定数
のようにEM／Ｆ＝一定等で運転されるのが一般
的である。 In addition, the voltage E M of the motor 6 (that is, the output voltage of the V power supply 2) is set as E M /F=K in order to avoid iron core saturation of the motor 6 (Equation 2) K: as a constant, E M /F= Generally, it is operated at a constant rate.
フアン７は電動機６により駆動されており、従
つて風路８に流れる風量は電動機６の回転数(N)、
即ちＶ電源２の出力周波数(F)によつて制御される
ことになる。この時、入口ベーン９は風量制御に
関与せず、省エネルギのために風路８の風路抵抗
を小さくしておく必要があり、全開又は全開付近
の一定開度としておく。 The fan 7 is driven by the electric motor 6, so the amount of air flowing into the air passage 8 is determined by the rotation speed (N) of the electric motor 6,
That is, it is controlled by the output frequency (F) of the V power supply 2. At this time, the inlet vane 9 is not involved in air volume control, and the air passage resistance of the air passage 8 must be kept small for energy saving, and the opening degree is set to be fully open or at a constant opening degree close to fully open.
即ち、信号線１０ａの信号によつてＶ電源２の
出力周波数(F)が制御され、信号線１０ｂの信号に
よつて入口ベーン９は一定開度となつている。 That is, the output frequency (F) of the V power source 2 is controlled by the signal on the signal line 10a, and the inlet vane 9 is kept at a constant opening degree by the signal on the signal line 10b.
他方、Ｃ電源１の運転時は開閉器３閉、開閉器
４，５開となつており、電動機６はＣ電源１、即
ち一定の商用電源周波数FCで駆動され、従つて
フアン７は定速で回転する。この場合には風路８
の流体量は入口ベーン９によつて制御される。即
ち信号線１０ｂの信号によつてフアン７の出力風
量は制御される。 On the other hand, when the C power source 1 is in operation, the switch 3 is closed and the switches 4 and 5 are open, and the electric motor 6 is driven by the C power source 1, that is, at a constant commercial power frequency F C , and therefore the fan 7 is driven at a constant frequency. Rotate at high speed. In this case, air path 8
The fluid volume of is controlled by the inlet vane 9. That is, the output air volume of the fan 7 is controlled by the signal on the signal line 10b.
Ｖ電源２からＣ電源１への切替は開閉器４，５
開、及び開閉器３閉、の操作によつて行われる。
Ｖ電源２は大容量電動機に適量するような場合に
は、値段をさげるために、電動機容量までのＶ電
源とせず、通常の運転をＶ電源で行う程度に小さ
くすることが多い。このフアンの例のような時、
Ｖ電源２の容量は運転周波数上限を商用周波数
FCのＸ％とすれば、ほゞ（Ｘ／100）3に比例した値と
することが出来る。 Switching from V power supply 2 to C power supply 1 is done using switches 4 and 5.
This is done by opening the switch 3 and closing the switch 3.
When the appropriate amount of V power supply 2 is used for a large-capacity motor, in order to reduce the price, the V power supply is not used up to the capacity of the motor, but is often made small enough to perform normal operation with the V power supply. In times like this example of Juan,
The capacity of V power supply 2 is set so that the upper limit of operating frequency is the commercial frequency.
If it is X% of F C , it can be set to a value approximately proportional to (X/100) 3 .
例えば1000Kwのモータで、力率cosθ＝85％、
モータ効率η＝90％のときには、電動機容量の
1000KwまてＶ電源運転しようとすれば
1000／0.85×0.9≒1310kVA
程度のＶ電源が必要であるが、通常運転が商用周
波数FCのｘ＝80％の範囲であるとすれば
1310×（80／100）3≒670kVA
のＶ電源に選ぶことが出来る。 For example, for a 1000Kw motor, the power factor cosθ=85%,
When the motor efficiency η = 90%, the motor capacity is
If you want to operate a 1000KW V power supply, you will need a V power supply of about 1000/0.85×0.9≒1310kVA, but if normal operation is in the range of x=80% of the commercial frequency F C , then 1310×(80 /100) 3 Can be selected as a V power supply of ≒670kVA.
従つて、Ｖ電源２から商用電源１への切替及び
その逆の切替はＶ電源システムでは運転中にあり
うることであり、従来は前述の切替操作を電力検
出器１２を用いて行つていた。この場合の切替に
ついて第２図の制御回路で説明する。 Therefore, switching from the V power supply 2 to the commercial power supply 1 and vice versa can occur during operation in the V power supply system, and conventionally, the above-mentioned switching operation was performed using the power detector 12. . Switching in this case will be explained using the control circuit shown in FIG. 2.
まず、Ｖ電源２の運転中について説明する。電
力検出器１２にはＶ電源２に印加する商用電源１
の電圧と電動機６への電流が印加され、電動機６
への供給電力を算出し、一定値以上を検出したと
き出力を出すように構成されている。上記電力一
定値をＶ電源２の容量又はその近傍の値に選定
し、電力検出器１２が動作したときに接点１２ａ
を閉とし、従つてトリツプコイル５Ｔをドライブ
して開閉器５を開とし、タイマT1の時限後に投
入コイル３Ｃをドライブして開閉器３を閉として
Ｖ電源２からＣ電源１に切替える。タイマT1の
時限は開閉器３を投入する時、電動機６の残留電
圧が減少するのを待つ時限である。投入コイル、
トリツプコイルの電流はそれぞれ投入、トリツプ
が完了すれば、自己しや断するように接点３ｂ，
５ａを用いている。接点１３ａが閉となつても、
上記接点１２ａの閉と同様に動作するが、接点１
３ａはＶ電源２故障の異常時等にＣ電源１に切替
えるために設けてある。以上のように、接点１２
ａ又は１３ａの閉で、第１の開閉手段によりＶ→
Ｃ電源へ切替えられる。 First, the operation of the V power supply 2 will be explained. The power detector 12 has a commercial power supply 1 applied to the V power supply 2.
voltage and current to the motor 6 are applied, and the motor 6
It is configured to calculate the power supplied to the device and output an output when it detects a certain value or more. The above constant power value is selected as the capacity of the V power supply 2 or a value close to it, and when the power detector 12 operates, the contact 12a
is closed, the trip coil 5T is driven to open the switch 5, and after the timer T1 expires, the closing coil 3C is driven to close the switch 3 and the V power supply 2 is switched to the C power supply 1. The time limit of the timer T1 is a time limit for waiting for the residual voltage of the motor 6 to decrease when the switch 3 is closed. input coil,
The current of the trip coil is turned on, and when the trip is completed, the contact 3b,
5a is used. Even if the contact 13a is closed,
It operates in the same way as closing contact 12a above, but contact 1
3a is provided for switching to the C power supply 1 in the event of an abnormality such as a failure of the V power supply 2. As described above, contact 12
When a or 13a is closed, the first opening/closing means causes V→
Switched to C power supply.
次にＣ電源１の運転中にＶ電源２へ切替える時
について説明する。Ｖ電源２を導入する目的は、
省エネルギを得るためであり、Ｖ電源２の運転領
域ではＶ電源２で電動機６を運転したい。Ｃ電源
１の運転中に電力検出器１２が所定値以下（接点
１２ａの開と必ずしも一致しなくてもよい）を検
出したとき、接点１２ｂが閉となり、Ｖ電源２故
障ではないことを条件に（接点１３ｂ閉）、トリ
ツプコイル３Ｔをドライブして開閉器３を開と
し、タイマT2の時限後に投入コイル５Ｃをドラ
イブして開閉器５を閉としてＣ電源１からＶ電源
２に切替える。タイマT2の時限は電動機６が減
速してＶ電源２によるい回転数とほゞ同じになる
まで時間に選定している。コイル３Ｔ，５Ｃの電
流は接点３ａ，５ｂで自己しや断される。 Next, a description will be given of when switching to the V power supply 2 while the C power supply 1 is in operation. The purpose of introducing V power supply 2 is
This is to save energy, and in the operating range of the V power supply 2, it is desired to operate the electric motor 6 with the V power supply 2. When the power detector 12 detects a predetermined value or less (which does not necessarily correspond to the opening of the contact 12a) during operation of the C power supply 1, the contact 12b closes, provided that there is no failure of the V power supply 2. (contact 13b closed), the trip coil 3T is driven to open the switch 3, and after the timer T2 expires, the closing coil 5C is driven to close the switch 5 and the C power source 1 is switched to the V power source 2. The time limit of the timer T2 is selected to be the time until the electric motor 6 decelerates to become almost the same as the rotational speed generated by the V power supply 2. The currents in the coils 3T and 5C are automatically cut off at the contacts 3a and 5b.
以上のように接点１２ｂ閉て、第２の切替手段
によりＣ→Ｖ電源へ切替えられる。 As described above, the contact 12b is closed and the second switching means switches from C to V power source.
第３図はＶ電源２からＣ電源１に切替える時に
発生するトルクを説明する図であり、横軸は切替
前のＶ電源２の運転回転数、縦軸は切替時の発生
トルクを示す。 FIG. 3 is a diagram illustrating the torque generated when switching from the V power source 2 to the C power source 1, where the horizontal axis shows the operating rotational speed of the V power source 2 before switching, and the vertical axis shows the torque generated at the time of switching.
第３図によれば、Ｃ電源１への切替前にＶ電源
２で運転されている回転数によつて、Ｃ電源１へ
切替える時に発生するトルクが大きい場合（例え
ば70〜80％or20〜40％回転数）があり、これは起
動時のトルクの２〜３倍に達することもある。切
替時の発生トルクが大きいことは、切替時に流れ
る電流が大きいことを示し、切替時に電動機６に
熱が蓄積されることを意味する。 According to Fig. 3, depending on the rotation speed operated by V power supply 2 before switching to C power supply 1, if the torque generated when switching to C power supply 1 is large (for example, 70 to 80% or 20 to 40% % rotation speed), which can reach 2 to 3 times the starting torque. A large generated torque during switching indicates that a large current flows during switching, and means that heat is accumulated in the electric motor 6 during switching.
従来の電源装置は以上のように構成されている
ので、Ｖ電源２からＣ電源１への切替が負荷の変
動等によつて短時間のうちに多数回実行される
と、切替時の大電流によつて電動機の過熱が蓄積
されてゆき、電動機を焼損に至らしめることにな
り、また焼損に至らなくても電動機のコイル絶縁
劣化を促進して電動機の寿命を短かくする等の欠
点があつた。 Conventional power supply devices are configured as described above, so if switching from V power supply 2 to C power supply 1 is performed many times in a short period of time due to load fluctuations, a large current at the time of switching occurs. As a result, overheating of the motor accumulates, leading to burnout of the motor, and even if burnout does not occur, there are disadvantages such as promoting deterioration of the motor coil insulation and shortening the life of the motor. Ta.
この発明は、上記のような従来のものの欠点を
除去するためになされたもので、電動機の温度が
所定値以上のとき作動する温度検出器を設けて、
この温度検出器が作動している時は切替をロツク
することにより、短時間のうちに多数回切替を行
わせないようにして、電動機の異常過熱を防止で
きる電源切替装置を提供することを目的としてい
る。
This invention was made in order to eliminate the drawbacks of the conventional ones as described above, and includes a temperature detector that operates when the temperature of the electric motor exceeds a predetermined value.
It is an object of the present invention to provide a power supply switching device that can prevent abnormal overheating of a motor by locking the switching when the temperature detector is operating, thereby preventing the switching from being performed multiple times in a short period of time. It is said that
以下、この発明の一実施例について説明する。
第４図において、１４は電動機の温度が所定値以
上の時、作動する温度検出器（図示せず）の動作
時開の温度検出器接点である。他の符号は第２図
と同一又は相当部分を示す。
An embodiment of the present invention will be described below.
In FIG. 4, reference numeral 14 denotes a temperature sensor contact that is open when a temperature sensor (not shown) is activated when the temperature of the motor is above a predetermined value. Other symbols indicate the same or corresponding parts as in FIG. 2.
第４図において、接点１２ａ又は接点１３ａが
閉となれば、第２図と同様にトリツプコイル５
Ｔ、投入コイル３Ｃにより開閉器５，３がそれぞ
れ開、閉となつてＶ電源２からＣ電源１に切替え
られる。その後、直ちに負荷減となつて電力検出
器１２の接点１２ｂが閉となつたとき、電動機６
が次のＶ電源２からＣ電源１への切替に耐えられ
ない温度に上昇していれば、温度検出器接点１４
が開となり、トリツプコイル３Ｔ、投入コイル５
Ｃはドライブされず、Ｃ電源１による電動機６の
運転が継続される。次のＶ電源２からＣ電源１へ
の切替に耐えられる温度にい電動機が冷却される
と、温度に検出器接点１４が閉となり投入コイ
ル、５Ｃ、トリツプコイル３Ｔのドライブ阻止は
解除されて、このとき接点１２ｂが閉であればＶ
電源２への切替がトリツプコイル３Ｔ、投入コイ
ル５Ｃによつて行われる。 In FIG. 4, if the contact 12a or 13a is closed, the trip coil 5
The switches 5 and 3 are opened and closed by the T and closing coils 3C, respectively, and the V power supply 2 is switched to the C power supply 1. Thereafter, when the load immediately decreases and the contact 12b of the power detector 12 closes, the motor 6
If the temperature has risen to a temperature that cannot withstand the next switching from V power supply 2 to C power supply 1, temperature sensor contact 14
is open, trip coil 3T, closing coil 5
C is not driven, and the motor 6 continues to be operated by the C power source 1. When the motor is cooled down to a temperature that can withstand the next switching from V power supply 2 to C power supply 1, the detector contact 14 closes and the drive prevention of the closing coil, 5C, and trip coil 3T is released. When contact 12b is closed, V
Switching to the power source 2 is performed by a trip coil 3T and a closing coil 5C.
なお、以上の説明では、温度検出器１４の動作
で、第１の開閉手段によるＶ電源２からＣ電源１
への切替を阻止するのに、第２の開閉手段による
Ｃ電源１からＶ電源２への切替を阻止するよう実
施例で説明したが、Ｖ電源２からＣ電源１への切
替を阻止する、あるいは両方の切替を阻止する等
の他の方法によつてもよい。 In addition, in the above explanation, the operation of the temperature detector 14 causes the voltage to change from the V power supply 2 to the C power supply 1 by the first opening/closing means.
Although it has been explained in the embodiment that the switching from the C power supply 1 to the V power supply 2 by the second opening/closing means is prevented in order to prevent the switching from the V power supply 2 to the C power supply 1, Alternatively, other methods such as blocking both switching may be used.
以上のように、この発明によれば、Ｖ電源から
Ｃ電源に、あるいはＣ電源からＶ電源に切替える
とき、電動機に蓄積される熱量が十分定常の冷却
状態になつていることを条件に次の切替を行うよ
うに構成したので、電動機の熱的破損を防止で
き、また熱的な絶縁劣化を防止して長期間、安全
な運転を続けることができる効果がある。
As described above, according to the present invention, when switching from a V power source to a C power source or from a C power source to a V power source, the amount of heat accumulated in the electric motor is in a sufficiently steady state of cooling, and the following Since the motor is configured to perform switching, it is possible to prevent thermal damage to the electric motor, and also to prevent thermal insulation deterioration, so that safe operation can be continued for a long period of time.
第１図はＶ電源システム図、第２図は従来の制
御回路図、第３図はＶ→Ｃ電源切替時に発生する
トルク説明図、第４図はこの発明の一実施例の制
御回路図である。
１……商用(C)電源、２……可変周波数（Ｖ）電
源、３，４，５……開閉器、１２……電力検出
器、３Ｃ，５Ｃ……開閉器３，５の投入コイル、
３Ｔ，５Ｔ……開閉器３，５のトリツプコイル、
１２ａ，１２ｂ……電力検出器１２の動作時閉、
開接点、T1，T2……タイマー、１３ａ……条件
リレー、１４……温度検出器接点、なお、図中、
同一符号は同一、又は相当部分を示す。
Fig. 1 is a V power supply system diagram, Fig. 2 is a conventional control circuit diagram, Fig. 3 is an explanatory diagram of the torque generated when switching from V to C power supply, and Fig. 4 is a control circuit diagram of an embodiment of the present invention. be. 1... Commercial (C) power supply, 2... Variable frequency (V) power supply, 3, 4, 5... Switch, 12... Power detector, 3C, 5C... Closing coil of switches 3 and 5,
3T, 5T...trip coils of switches 3 and 5,
12a, 12b...closed when the power detector 12 is in operation;
Open contact, T1 , T2 ...Timer, 13a...Condition relay, 14...Temperature detector contact, In addition, in the figure,
The same reference numerals indicate the same or equivalent parts.
Claims (1)
源及び可変周波数電源と、前期可変周波数電源か
ら前記商用電源へ切替える第１の開閉手段と、前
記商用電源から前記可変周波数電源へ切替える第
２の開閉手段とを有する電源切替装置において、
前記電動機の温度が所定以上である時作動する温
度検出器を設け、前記温度検出器の作動時に開成
する温度検出器接点を前記第２の開閉手段又は第
２の開閉手段の回路のいずれか一方あるいは両方
に設けたことを特徴とする電源切替装置。1 A commercial power source and a variable frequency power source that are alternatively selected to supply power to the electric motor, a first opening/closing means that switches from the variable frequency power source to the commercial power source, and a second switching means that switches from the commercial power source to the variable frequency power source. In a power switching device having an opening/closing means,
A temperature detector that operates when the temperature of the electric motor is above a predetermined value is provided, and a temperature detector contact that opens when the temperature detector is activated is connected to either the second switching means or the circuit of the second switching means. Alternatively, a power supply switching device characterized in that it is provided on both sides.
Priority Applications (7)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60007706A JPS61167394A (en) | 1985-01-18 | 1985-01-18 | Power source switching system |
| KR1019850005224A KR900000767B1 (en) | 1985-01-18 | 1985-07-22 | Overheat preventing system of a.c. motor |
| EP90116144A EP0409286B1 (en) | 1984-07-28 | 1985-07-29 | Overheat preventing system of A.C. motor |
| DE3588032T DE3588032T2 (en) | 1984-07-28 | 1985-07-29 | Overheating protection for AC motor. |
| EP85305375A EP0171245B1 (en) | 1984-07-28 | 1985-07-29 | Overheat preventing system of a.c. motor |
| DE8585305375T DE3583262D1 (en) | 1984-07-28 | 1985-07-29 | OVERHEATING PROTECTION FOR AC MOTORS. |
| US07/494,840 US4977363A (en) | 1984-07-28 | 1990-03-16 | Overheat preventing system of A.C. motor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60007706A JPS61167394A (en) | 1985-01-18 | 1985-01-18 | Power source switching system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61167394A JPS61167394A (en) | 1986-07-29 |
| JPH0368640B2 true JPH0368640B2 (en) | 1991-10-29 |
Family
ID=11673186
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60007706A Granted JPS61167394A (en) | 1984-07-28 | 1985-01-18 | Power source switching system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61167394A (en) |
-
1985
- 1985-01-18 JP JP60007706A patent/JPS61167394A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61167394A (en) | 1986-07-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPS62178832A (en) | Control circuit for air conditioner with inverter | |
| JPH0665926B2 (en) | Air volume control method | |
| US6239523B1 (en) | Cutout start switch | |
| JP3721312B2 (en) | Sealed compressor | |
| JPH0368640B2 (en) | ||
| JPH05293010A (en) | Hair dryer | |
| US4977363A (en) | Overheat preventing system of A.C. motor | |
| JPH0368639B2 (en) | ||
| JP3649752B2 (en) | Air conditioner | |
| JP3435068B2 (en) | Safe starting device for single-phase induction motor and starting control method thereof | |
| KR900000767B1 (en) | Overheat preventing system of a.c. motor | |
| JP2529366B2 (en) | Heating cooker | |
| JP2635348B2 (en) | Split-phase starting Single-phase induction motor starting device | |
| JPH0238867B2 (en) | ||
| US4689508A (en) | Switched shaded-pole type induction motor | |
| JPS61167390A (en) | Operating switching system for number of pole change motor | |
| JPH1014268A (en) | Control of star-delta starting electromagnetic contactor | |
| JPH044397Y2 (en) | ||
| JPH0458722A (en) | Overload protective circuit for motor | |
| JP2598701Y2 (en) | Water supply device | |
| US10250167B2 (en) | Device and method for starting a motor for alternating current | |
| JPH0438210Y2 (en) | ||
| JP2670347B2 (en) | Blower | |
| JPS62188998A (en) | Flammable gas recombination equipment | |
| JPH0384350A (en) | Air conditioner |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |