TW201743535A - Switch device - Google Patents

Abstract

A switch device comprises a first relay and a first switch unit in series connection between an AC power source and a load, and a second relay and a second switch unit in series connection between the AC power source and the load, where the first switch unit has a first silicon-controlled rectifier (SCR) and the second switch unit has a second SCR. When the AC power source begins supplying an AC voltage which is a predetermined AC voltage, both first and second relays, in response to a first control signal, turns on for a first predetermined time period after which, in response to a second control signal, both first and second SCRs turns on, such that the AC voltage from the AC power source is transferred to the load either via the first relay and first SCR or via the second relay and second SCR.

Description

Switching device

The present invention relates to a switching device, and more particularly to a switching device for a power distribution system.

The switching devices configured in the power distribution system can be divided into manual or automatic types, and can be operated to select to supply power to the load or to interrupt the power supply to the load. A transfer switch that is commonly applied to this automatic switching device can be appropriately designed to perform automatic switching control between a plurality of supply sources. When an abnormality of one of the plurality of power supply sources (such as mains) is abnormal, such as when the voltage is unstable or the power is off, the automatic switching operation of the switch can be used to make another standby power supply (such as uninterrupted power) System) continue to supply stable power.

However, the switch is likely to generate an instantaneous high transient current when performing a switching operation, such as inrush current. In particular, when a relay is used as the switch, the transient current easily exceeds the limit that the relay can withstand. In addition, an arc generated when the relay is disconnected or engaged may cause electrical contact wear. In this way, when the situation is serious, a plurality of electrical contacts may be caused to be welded together, so that the switch cannot be switched normally. In view of this, the existing switch has an improved space.

Accordingly, it is an object of the present invention to provide a switching device that can withstand high transient inrush currents while maintaining high power supply reliability.

Therefore, the switching device of the present invention is adapted to be electrically connected between an AC power source for supplying an AC voltage and a load, the AC power source having a live line output end and a neutral line output end, the load having a Firewire connection And a neutral line connection end, and the switch device comprises a first relay, a first switch unit, a second relay, and a second switch unit.

The first relay and the first switch unit are connected in series between the live line output end of the alternating current power source and the live line connection end of the load, and the first relay is electrically connected to the live line output end of the alternating current power source and is responsive to The first switching unit is electrically connected to the live connection of the load, and includes at least a first controlled rectifier, and is turned on or off in response to a second control signal.

The second relay and the second switch unit are connected in series between the neutral line output end of the AC power source and the neutral line connection end of the load, and the second relay electrically connects the neutrality of the AC power source The line output terminal is turned on or off in response to the first control signal, the second switch unit is electrically connected to the neutral line connection end of the load, and includes at least a second controlled rectifier, and is responsive to the second The control signal is either conductive or non-conductive.

Wherein, when the AC power source initially supplies the AC voltage and the AC voltage is a predetermined AC voltage, the first and second relays are turned on in response to the first control signal, and in the first and second After the first predetermined period of time after the relay is turned on, the first controlled rectifier of the first switching unit and the second controlled rectifier of the second switching unit are turned on in response to the second control signal, so that the AC power source is from the AC power source. The AC voltage is transmitted to the load via the first relay and the first controlled rectifier or via the second relay and the second controlled rectifier.

The effect of the invention is that the controlled rectifier of the first and second switching units can maintain the reliability of the automatic switching device by utilizing its ability to withstand high transient currents when the AC power source is initially powered. Degree requirements.

Referring to FIG. 1, the switching device 10 and the switching device 10' of the present invention can be disposed in a power distribution system 1, and the switching device 10 is adapted to be electrically connected to an AC power supply 200 for supplying an AC voltage Vp and a load 100. The switching device 10' is adapted to be electrically connected between a backup power source 300 for supplying a backup voltage Vs and the load 100. The AC power supply 200 and the backup power supply 300 each have a live line output terminal L ₁ and a neutral line output terminal N ₁ . The load 100 has a live line connection end L and a neutral line connection end N.

Referring to FIG. 2, a first embodiment of the switch device 10 of the present invention includes a first relay 1, a first switch unit 2, a second relay 3, and a second switch unit 4. It should be noted that the switching device 10' has the same circuit structure as the switching device 10, and details are not described below.

The first relay 1 and the first switch unit 2 are connected in series between the live line output terminal L _{1 of} the AC power source 200 and the live line connection end L of the load 100, and the first relay 1 is electrically connected to the AC power source. The live line output terminal L _{1 of} 200 is turned on or off in response to a control signal S1. The first switch unit 2 is electrically connected to the live line connection end L of the load 100 and includes two first diodes 21~ 22. Two second diodes 23-24, a first controlled rectifier (SCR) 25, and a third relay 26. The first controlled rectifier 25 is turned on or off in response to a control signal S2. The third relay 26 is turned on or off in response to a control signal S3. The control signal S1 may be a first control signal, and the control signal S2 may be a second control signal, and the control signal S3 may be a third control signal.

The second relay 3 and the second switch unit 4 are connected in series between the neutral line output end N1 of the AC power source 200 and the neutral line connection end N of the load 100, and the second relay 3 is electrically connected. The neutral line output terminal N1 of the AC power source 200 is turned on or off in response to the control signal S1, and the second switch unit 4 is electrically connected to the neutral line connection terminal N of the load 100, and includes two The diodes 41 to 42 , the two fourth diodes 43 to 44 , a second controlled rectifier 45 , and a third relay 46 . The second controlled rectifier 45 is turned on or off in response to the control signal S2. The third relay 46 is turned on or off in response to the control signal S3.

Referring to FIG. 3, when the AC power source 200 supplies the AC voltage Vp at a time t0, and the AC voltage Vp is a predetermined AC voltage, for example, 110 volts, the AC power source 200 normally supplies power, and the first relay 1 and the second relay 3 is turned on in response to the control signal S1, and the first switching unit is turned off after a first predetermined period T1 after the first relay 1 and the second relay 3 are turned on, that is, from time t0 to time t1. The first controlled rectifier 25 of the second switching unit 25 and the second controlled rectifier 45 of the second switching unit 4 are turned on in response to the control signal S2 at time t1, so that the alternating voltage Vp from the alternating current power source 200 passes through the first A relay 1 is coupled to the first controlled rectifier 25 or via the second relay 3 and the second controlled rectifier 45 to the load 100.

In detail, in the positive half cycle of the AC voltage Vp, the AC voltage Vp is transmitted to the load 100 via the first relay 1 and the first controlled rectifier 25, and at this time, the AC current is from the AC power source 200. The live line output terminal L1 flows through the conduction path formed by the first relay 1, the first diode 21, the first controlled rectifier 25 and the second diode 24, and is connected to the live line connection of the load 100. The terminal L flows from the neutral line connection end N of the load 100 through the third diode 42 , the second controlled rectifier 45 , the fourth diode 43 , and the second relay 3 . The conduction path flows back to the neutral line output terminal N1 of the AC power source 200. During the negative half cycle of the AC voltage Vp, the AC voltage Vp is transmitted to the load 100 via the second relay 3 and the second controlled rectifier 45. At this time, the AC current is from the neutral line of the AC power source 200. The output terminal N1 flows through the second relay 3, the third diode 41, the second controlled rectifier 45, and the fourth diode 44 to the neutral connection terminal N of the load 100, and then The live wire connection end L of the load 100 is returned to the AC power source 200 via the conduction path formed by the first diode 22, the first controlled rectifier 25, the second diode 23 and the first relay 1 Fire line output L1. Thereby, when the switching device 10 is turned on and the AC voltage Vp of the AC power source 200 is transmitted to the load 100, that is, the forward bias and the internal resistance of the first controlled rectifier 25 and the second controlled rectifier 45 are transmitted. And the forward bias and internal resistance of the first, second, third, and fourth diodes 21-44 to suppress transient transient AC currents in the positive half cycle and the negative half cycle.

Then, the first and second step-controlled rectifiers 25, 45 are responsive to the control signal S2, and are switched to be non-conducting after being continuously turned on for a second predetermined period T2. The second predetermined period T2 is from time t1 to time t3. The third relays 26, 46 after a third predetermined period T3 (from time t1 to time t2) shorter than the second predetermined period T2 after the first and second pilot rectifiers 25, 45 are turned on And being turned on in response to the third control signal S3 at time t2, so that the AC voltage Vp via the first relay 1 is further via the first switching unit during the conduction of the first and second step-controlled rectifiers 25, 45 The third relay 26 of 2 is transmitted to the load 100, and the AC voltage Vp via the second relay 3 is transmitted to the load 100 via the third relay 46 of the second switching unit 4, and When the first and second step-controlled rectifiers 25, 45 are not conducting, the AC voltage Vp from the AC power source 200 passes through the third relay 26 via the first relay 1 and the first switching unit 2 or via the first The second relay 3 and the third relay 46 of the second switching unit 4 are transferred to the load 100.

More specifically, in the positive half cycle of the AC voltage Vp, the AC voltage Vp is transmitted to the load 100 via the first relay 1 and the third relay 26, and at this time, the AC current is from the AC power source 200. The live line output terminal L1 flows through the conduction path formed by the first relay 1 and the third relay 26, and is transmitted to the live line connection end L of the load 100, and then flows through the neutral line connection end N of the load 100. The conduction path formed by the three relays 46 and the second relay 3 flows back to the neutral line output terminal N1 of the AC power source 200. In the negative half cycle of the AC voltage Vp, the AC voltage Vp is transmitted to the load 100 via the second relay 3 and the third relay 46 of the second switching unit 4, and the AC current is from the AC power source 200. The neutral line output terminal N1 flows through the third relay 46 to the neutral line connection end N of the load 100, and then returns from the live line connection end L of the load 100 to the first relay 1 via the third relay 26 Go to the live line output L1 of the AC power source 200. That is, when the switching device 10 is turned on for a period of time and the AC voltage Vp is stably sent to the load 100, the current does not need to pass through the first and second controlled rectifiers 25, 45 and the first to fourth two. The pole bodies 21 to 44 only flow through the third relays 26, 46.

Thereby, the conduction losses of the diode and the controlled rectifier can be reduced by using the lower on-resistance of the third relays 26 and 46, and the first and second controlled rectifiers 25, 45 is switched to non-conduction after the second predetermined period T2 is continuously turned on, which can save power and improve the efficiency of the switching device 10, and the reliability of the switching device 10 can be further improved without fan cooling.

Referring to FIG. 3, when the AC voltage Vp is detected to be zero during the conduction period of the first relay 1, the second relay 3, and the third relays 26, 46, the AC voltage Vp of the AC power source 200 In the case of a dropout, the first and second relays 1, 3 switch from conduction to non-conduction in response to the control signal S1 at time td, and the third relays 26, 46 switch from conduction in response to the control signal S3. It does not turn on.

It should be noted that the first relay 1 ′ of the switching device 10 ′ shown in FIG. 2 is turned on in response to the control signal S1 ′ when the backup power supply 300 initially supplies the backup voltage V s, and is in the switching device. The first and second relays 1 and 3 of 10 and the third relays 26 and 46 are kept on during the conduction period, when the AC voltage Vp of the AC power source 200 fails and the first and second relays 1, 3 and the third relay are disabled. 26, 46 is turned off for a predetermined period T _BBM (from time td to time ts), the first and second controlled rectifiers 25', 45' of the switching device 10' are responsive to the control at time ts The signal S2' is turned on to enable the load 100 to be powered by the backup power supply 300, and during the power conversion, the high transient switching current is suppressed by the conduction periods of the first and second controlled rectifiers 25', 45'. . Then, the third relays 26', 46' are switched from non-conducting to conducting during the conduction of the first and second step-controlled rectifiers 25', 45', after which the first and second controlled rectifiers are turned on. During the 25', 45' non-conduction period, the backup voltage Vs from the backup power source 300 is passed through the first relay 1' and the third relay 26' of the first switching unit 2' or via the second relay The third relay 46' with 3' and the second switching unit 4' is delivered to the load 100. In this way, after the standby power supply 300 stably supplies the backup voltage Vs, the conduction loss of the diode and the controlled rectifier can be further reduced.

Referring to FIG. 4, when the magnitude of the AC voltage Vp is less than the predetermined AC voltage during the conduction of the first relay 1, the second relay 3, and the third relays 26, 46, the AC power source is The AC voltage Vp of 200 is a temporary low voltage, and the first and second step-controlled rectifiers 25, 45 switch from non-conduction to conduction in response to the control signal S2 at time t4, and continue to conduct for a fourth predetermined period T4. After switching to non-conduction. The fourth predetermined time T4 is from time t4 to time t6. The third relays 26, 46 are shorter than the fifth predetermined period T5 of the fourth predetermined period T4 (i.e., time t4 to time t5) after the first and second pilot rectifiers 25, 45 are turned on, In response to the control signal S3, switching from on to non-conduction. Since the third relays 26, 46 are switched to be non-conducting during the conduction of the diode and the controlled rectifier, the third relays 26, 46 do not generate an arc. After the first and second controlled rectifiers 25, 45 and the third relays 26, 46 are not turned on, the first and second relays 1, 3 are turned on in response to the control signal S1 at time t7. Switch to non-conduction to achieve back-feed protection. At this time, it should be noted that the switching device 10' shown in FIG. 2 is after the first and second relays 1, 3 are turned off for a predetermined period T _BBM (from time t7 to time t8). Waiting for the first and second step-controlled rectifiers 25', 45' to be turned on in response to the control signal S2' at time t8 for successively supplying power from the backup power source 300, and during the power conversion, by the first And the forward bias and internal resistance of the second voltage controlled rectifiers 25', 45' to suppress high transient inrush current. The third relays 26', 46' are switched from non-conducting to conducting during the conduction of the first and second step-controlled rectifiers 25', 45' to further reduce the conduction of the diode and the controlled rectifier. The loss increases the power supply efficiency of the switching device 10' and achieves the effect of energy saving and carbon reduction.

Referring to FIG. 5 and FIG. 6, FIG. 5 is a second embodiment of the switch device 10 of the present invention. The difference from the first embodiment is that the first switch unit 2 further includes a first switch-controlled rectifier 25 connected in parallel. The first switch 27 has a control terminal for receiving a control signal S4 and is turned on or off in response to the control signal S4. The first switch 27 normally operates in a non-conducting state. After the magnitude of the AC voltage Vp is detected to be less than the predetermined AC voltage, during the conduction of the first and second relays 1, 3 and at the first and second step-controlled rectifiers 25, 45 When switching from conducting to non-conducting, the first switch 27 switches from non-conducting to conducting in response to the control signal S4, and continues to conduct a sixth predetermined before the first and second relays 1, 3 are switched to be non-conducting. Period T6. The sixth predetermined period T6 is from time t6' to time tc. The control signal S4 can be a fourth control signal. In this embodiment, the first switch 27 is one of a metal oxide semiconductor field effect transistor (MOSFET) and an insulated gate bipolar transistor (IGBT).

Referring to FIG. 7A and FIG. 7B, FIG. 7A illustrates that after the first controlled rectifier 25 is switched from on to off, the current I ₂₅ flowing through the first controlled rectifier 25 does not immediately become zero, that is, The off state has not yet been reached. In general, the first controlled rectifier 25 is typically turned off when the current I _{25 is} less than its sustain current (close to 0 A). As shown in FIG. 7B, therefore, when the first controlled rectifiers 25, 45 are turned into non-conducting in response to the control signal S2, the first predetermined period 27 is continuously turned on by the first switch 27, because the first The turn-on voltage drop of the switch 27 is less than the forward bias of the first step-controlled rectifier 25, so that current is transferred to the first switch 27, which can accelerate the turn-on and turn-off of the first step-controlled rectifier 25. Then at time tc, the first switch 27 switches from conduction to non-conduction in response to the control signal S4, such that the alternating current flowing through the load 100 is turned off, and, after the first switch 27 is turned off, flows through. The current of the second controlled rectifier 45 is also naturally lower than the sustain current, resulting in the second controlled rectifier 45 being turned off. Thereby, the closing time of the first and second step-controlled rectifiers 25, 45 can be shortened, and the predetermined period T _{BBM of} the switching device 10 during power conversion can be saved.

Referring to FIG. 8, a third embodiment of the switching device 10 of the present invention is different from the second embodiment in that the second switching unit 4 further includes a second switch 47 connected in parallel to the second controlled rectifier 45. The second switch 47 has a control terminal for receiving the control signal S4, and is turned on or off in response to the control signal S4, and the second switch 47 is normally operated in a non-conducting state. After the magnitude of the AC voltage Vp is detected to be less than the predetermined AC voltage, during the conduction of the first relay 1 and the second relay 3 and at the first and second step-controlled rectifiers 25, 45 When switching from conducting to non-conducting, the second switch 47 switches from non-conducting to conducting in response to the control signal S4, and continuously turns on the sixth predetermined before the first and second relays 1, 3 are switched to be non-conducting. Period T6 (as shown in Figure 6). In this embodiment, the second switch 47 is one of a metal oxide semiconductor field effect transistor (MOSFET) and an insulated gate bipolar transistor (IGBT). With the first switch 27 and the second switch 47, the first and second step-controlled rectifiers 25, 45 can be surely accelerated to cut off, thereby shortening the power conversion time.

Referring to Figures 9 and 10, a fourth embodiment of the switching device 10 of the present invention differs from the first to third embodiments in the circuit configuration of the first and second switching units 2, 4. The first switching unit 2 includes a first controlled rectifier 25, a third controlled rectifier 28, and two first diodes 21, 22. The first and third step-controlled rectifiers 25, 28 are electrically connected in series with each other between the second end of the first relay 1 and the live connection L of the load 100, and each has a Control terminal of signal S2. The first diodes 21, 22 are electrically connected in series between the second end of the first relay 1 and the live connection end L of the load 100, and the first diodes 21, 22 are respectively The anodes are electrically connected to the cathodes of the first and third step-controlled rectifiers 25, 28, respectively. The second switching unit 4 includes a second controlled rectifier 45, a fourth controlled rectifier 48, and two third diodes 41, 42. The second controlled rectifier 45 and the fourth controlled rectifier 48 are electrically connected in series with each other between the second end of the second relay 3 and the neutral connecting end N of the load 100, and each has a A control terminal for receiving the control signal S2. The third diodes 41 and 42 are electrically connected in series between the second end of the second relay 3 and the neutral line connection end N of the load 100, and the third diode 41, The respective anodes of the 42 are electrically connected to the cathodes of the respective second and fourth step-controlled rectifiers 45, 48.

In this way, during the positive half cycle of the AC voltage Vp, the AC voltage Vp is transmitted to the load 100 via the first relay 1 and the first controlled rectifier 25, and at this time, the AC current is the hot line from the AC power source 200. The output terminal L1 flows through the first relay 1, the first controlled rectifier 25, the first diode 22 is transmitted to the live line connection end L of the load 100, and then flows from the neutral line connection end N of the load 100. The conduction path formed by the fourth controlled rectifier 48, the third diode 41, and the second relay 3 flows back to the neutral line output terminal N1 of the AC power source 200. During the negative half cycle of the AC voltage Vp, the AC voltage Vp is transmitted to the load 100 via the second relay 3 and the second controlled rectifier 45. At this time, the AC current is from the neutral line of the AC power source 200. The output terminal N1 flows through the second controlled rectifier 45, the third diode 42 and the second controlled rectifier 45 to the neutral connection terminal N of the load 100, and then connects from the live line of the load 100. The terminal L is returned to the live line output terminal L1 of the AC power source 200 via the third controlled rectifier 28 and the conduction path formed by the first diode 21 and the first relay 1 . As shown in FIG. 10, when the AC voltage Vp of the AC power source 200 is a temporary low voltage, the switching device 10 can also allow the third relays 26, 46 to be in the first to fourth step-controlled rectifiers. The fourth predetermined period T4 of 25, 28, 45, 48 conduction is switched from on to non-conducting, so that no switching arc is generated, and during switching of the power supply that is powered by the backup power source 300, the switching device 10' The first to fourth step-controlled rectifiers 25', 28', 45', 48' can be used to suppress transient inrush current flowing into the load 100 instantaneously. Therefore, in the embodiment, the forward bias and the internal resistance of the first to fourth controlled rectifiers, and the first and third portions can also be transmitted when the AC power source 100 starts supplying power and performs power conversion. The forward bias and internal resistance of the diode suppress the transient inrush current of the positive half cycle and the negative half cycle.

In summary, the advantages of the automatic switching device of the present invention are as follows.

1. The switching device 10 and the first and second switching units 2, 4 of the switching device 10' can be formed by the first to fourth diodes 21-44 and a single controlled rectifier 25, 45. The bridge diode structure is implemented, and in the transient process in which the AC power supply 200 starts to supply power and performs power conversion, the switching is performed by using the controlled rectifier to utilize the high transient. The ability to sink current to maintain the electrical reliability requirements of the automatic switching device.

2. Since the conduction paths of the first and second switching units 2, 4 are connected in series by two diodes and a controlled rectifier, the forward bias of the diode and the controlled rectifier in the conducting state can be Voltage and internal resistance to suppress transient inrush current. And since the first and second switching units 2, 4 can use a single controlled rectifier 25, 45, the gate control mechanism is relatively simple.

3. When performing power conversion, the first and second switches 27, 47 may be connected in parallel to the step-controlled rectifier, and the first and second switches 27, 47 are used to transfer the on-current of the step-controlled rectifier to force 矽Since the rectifier is turned off, the turn-off time of the controlled rectifier can be shortened to accelerate the power conversion, and therefore, the object of the present invention can be achieved.

The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, and the simple equivalent changes and modifications made by the scope of the patent application and the patent specification of the present invention are It is still within the scope of the invention patent.

10‧‧‧Switching device
10'‧‧‧Switching device
1‧‧‧First relay
1'‧‧‧First Relay
2‧‧‧First switch unit
2'‧‧‧First switch unit
21, 22‧‧‧ first diode
21', 22'‧‧‧ first diode
23, 24‧‧‧ second diode
23', 24'‧‧‧ second diode
25‧‧‧First voltage controlled rectifier
25'‧‧‧First Voltage Controlled Rectifier
26‧‧‧ Third Relay
26'‧‧‧ Third Relay
27‧‧‧Second switch
27'‧‧‧second switch
28‧‧‧ Third voltage controlled rectifier
28'‧‧‧ Third Voltage Controlled Rectifier
3‧‧‧Second relay
3'‧‧‧Second relay
4‧‧‧Second switch unit
4'‧‧‧Second switch unit
41, 42‧‧‧ third diode
41', 42'‧‧‧ third diode
43, 44‧‧‧ fourth diode
43', 44'‧‧‧ fourth diode
45‧‧‧Second voltage controlled rectifier
45'‧‧‧Second voltage controlled rectifier
46‧‧‧third relay
46'‧‧‧ Third Relay
47‧‧‧second switch
47'‧‧‧Second switch
48‧‧‧4th voltage controlled rectifier
48'‧‧‧fourth voltage controlled rectifier
100‧‧‧ load
L‧‧‧Firewire connection
200‧‧‧AC power supply
N‧‧‧Neutral cable connection
300‧‧‧Reserved power supply
Vp‧‧‧AC voltage
L1‧‧‧Firewire output
Vs‧‧‧ spare voltage
N1‧‧‧Neutral output
T0~t8‧‧‧Time
T _BBM ‧‧‧ scheduled period
T1~T6‧‧‧First to sixth scheduled period

Other features and advantages of the present invention will be apparent from the embodiments of the present invention, wherein: FIG. 1 is a block diagram illustrating that the switching device of the present invention can be configured in a power distribution system; FIG. 2 is a circuit diagram A first embodiment of the switching device of the present invention is illustrated; FIG. 3 is a timing diagram illustrating the switching operation between the power supply normal and a power drop (dropout) of the first embodiment; FIG. FIG. 5 is a circuit diagram illustrating a second embodiment of the switching device of the present invention; FIG. 5 is a circuit diagram illustrating a switching operation between a power supply normal and a power supply temporary low voltage (brownout); 6 is a timing diagram, and FIG. 5 illustrates a switching operation between a power supply normal and a power supply temporary low voltage in the second embodiment; FIG. 7A and FIG. 7B are timing charts illustrating a second embodiment of the second embodiment. The first switch can accelerate the shutdown of the step-controlled rectifier and accelerate the power conversion; FIG. 8 is a circuit diagram illustrating a third embodiment of the switching device of the present invention; FIG. 9 is a circuit diagram illustrating one of the switching devices of the present invention The fourth embodiment; and FIG. 10 is a timing chart. The auxiliary FIG. 9 illustrates the switching operation of the fourth embodiment between a normal power supply and a temporary low voltage of the power supply.

10‧‧‧Switching device

10'‧‧‧ Switchgear

1‧‧‧First relay

1’‧‧‧First Relay

2‧‧‧First switch unit

2'‧‧‧First switch unit

21, 22‧‧‧ first diode

21’, 22’‧‧‧ first diode

23, 24‧‧‧ second diode

23’, 24’‧‧‧ second diode

25‧‧‧First voltage controlled rectifier

25’‧‧‧First Voltage Controlled Rectifier

26‧‧‧ Third Relay

26’‧‧‧ Third Relay

3‧‧‧Second relay

3’‧‧‧Second relay

4‧‧‧Second switch unit

4'‧‧‧Second switch unit

41, 42‧‧‧ third diode

41’, 42’‧‧‧ Third Dipole

43, 44‧‧‧ fourth diode

43’, 44’‧‧‧ fourth diode

45‧‧‧Second voltage controlled rectifier

45’‧‧‧Second voltage controlled rectifier

46‧‧‧third relay

46’‧‧‧ Third Relay

S1~S3‧‧‧ control signal

S1’~S3’‧‧‧ control signal

100‧‧‧ load

L‧‧‧Firewire connection

200‧‧‧AC power supply

N‧‧‧Neutral cable connection

300‧‧‧Reserved power supply

Vp‧‧‧AC voltage

L1‧‧‧Firewire output

Vs‧‧‧ spare voltage

N1‧‧‧Neutral output

Claims (10)

A switching device adapted to be electrically connected between an AC power source for supplying an AC voltage and a load, the AC power source having a Firewire output end and a neutral line output end, the load having a Firewire connection end and a a neutral line connection end, and the switch device includes: a first relay and a first switch unit connected in series between the live line output end of the alternating current power source and the live line connection end of the load, the first relay Electrically connecting the live line output of the AC power source and conducting or not conducting in response to a first control unit, the first switch unit is electrically connected to the live line connection end of the load, and includes at least a first controlled rectifier, and Translating or not conducting at least in response to a second control signal; and a second relay and a second switching unit are connected in series to each other at the neutral line output end of the AC power source and the neutral line connection end of the load The second relay is electrically connected to the neutral line output end of the AC power source and is turned on or off in response to the first control signal, and the second switch unit is electrically connected The neutral line connection end of the load includes at least a second controlled rectifier, and is turned on or off at least in response to the second control signal; wherein, when the AC power source initially supplies the AC voltage and the AC voltage When the predetermined voltage is a predetermined voltage, the first and second relays are turned on in response to the first control signal, and the first switching unit is in a first predetermined period after the first and second relays are turned on The first controlled rectifier and the second controlled rectifier of the second switching unit are turned on in response to the second control signal, so that the alternating voltage from the alternating current power source is connected to the first controlled rectifier via the first relay Or being transmitted to the load via the second relay and the second controlled rectifier. The switching device of claim 1, wherein: the first and second controlled rectifiers are switched to non-conducting after being continuously turned on for a second predetermined period in response to the second control signal; Each of the first and second switching units further includes a third relay, and is further turned on or off in response to a third control signal; and one of the second and second controlled rectifiers is shorter than the second After the third predetermined period of the predetermined period, the third relays are turned on in response to the third control signal, so that during the conduction of the first and second controlled rectifiers, the AC voltage via the first relay is also via The third relay of the first switching unit is transmitted to the load, and the alternating voltage via the second relay is also transmitted to the load via the third relay of the second switching unit, and at the first And the alternating current voltage from the alternating current power source is disconnected from the third relay via the first relay and the first switching unit or via the second relay and the second opening The third relay of the off unit is transferred to the load. The switching device of claim 2, wherein the first and second relays respond when the alternating voltage is detected to become zero during the on periods of the first, second, and third relays The first control signal S1 is switched from on to non-conducting, and the third relays are switched from on to non-conducting in response to the third control signal. The switching device of claim 3, wherein: when the magnitude of the alternating voltage is less than the predetermined alternating voltage during the first, second, and third relays being turned on, the The first and second controlled rectifiers switch from non-conducting to conducting in response to the second control signal, and are switched to non-conducting after being turned on for a fourth predetermined period; the third relays are in the first and second control a fifth predetermined period shorter than the fourth predetermined period after the rectifier is turned on, in response to the third control signal being switched from conducting to non-conducting; and in the first and second controlled rectifiers and the third relay After the non-conduction, the first and second relays switch from conducting to non-conducting in response to the first control signal. The switching device of claim 2, wherein: the first relay has a first end electrically connected to the live line of the AC power source, a second end, and a first control signal for receiving the first control signal a second terminal having a first end connected to the neutral line output of the AC power source, a second end, and a control end for receiving the first control signal; the first and the first The two controlled rectifiers each have a cathode, an anode, and a control terminal for receiving the second control signal; the third relays each have a first end, a second end, and a third for receiving the third a control end of the control signal, the first and second ends of the third relay of the first switch unit are electrically connected to the second end of the first relay and the live line end of the load, respectively, the second switch The first and second ends of the third relay of the unit are respectively electrically connected to the second end of the second relay and the neutral line connection end of the load; the first switch unit further includes two first two a pole body electrically connected to each other in series Between the second end of the first relay and the live connection of the load, the cathodes of the first diodes and the anode of the first controlled rectifier are electrically connected to each other, and the two second diodes Electrically connected in series with each other between the second end of the first relay and the live connection of the load, the anodes of the second diodes being electrically connected to the cathodes of the first controlled rectifier And the second switching unit further includes two third diodes electrically connected in series with each other between the second end of the second relay and the neutral line connection end of the load, the third two The cathodes of the pole bodies are electrically connected to the anode of the second controlled rectifier, and the two fourth diodes are electrically connected in series to each other at the second end of the second relay and the neutral of the load Between the line terminals, the anodes of the fourth diodes and the cathodes of the second voltage controlled rectifier are electrically connected to each other. The switching device of claim 5, wherein: the first switching unit further comprises a first switch connected in parallel to the first controlled rectifier, the first switch having a fourth control signal for receiving a fourth control signal a control terminal that is turned on or off in response to the fourth control signal, the first switch generally operating in a non-conducting state; and after the magnitude of the alternating voltage is detected to be less than the predetermined alternating voltage, When the first and second relays are turned on and when the second and second controlled rectifiers are switched from conductive to non-conductive, the first switch is switched from non-conducting to conducting in response to the fourth control signal, and The first and second relays are switched to be continuously turned on for a sixth predetermined period before being turned on. The switching device of claim 6, wherein: the second switch unit further includes a second switch connected in parallel to the second controlled rectifier, the second switch having a fourth control signal for receiving the fourth control signal a control terminal that is turned on or off in response to the fourth control signal, the second switch generally operating in a non-conducting state; and after the magnitude of the alternating voltage is detected to be less than the predetermined alternating voltage, Waiting for the first and second relays to be turned on and when the second and second step-controlled rectifiers are switched from on to off, the second switch is switched from non-conducting to conducting in response to the fourth control signal, and The first and second relays are switched to be continuously turned on for the sixth predetermined period before being turned on. The switching device of claim 7, wherein the first and second switches are each one of a metal oxide semiconductor field effect transistor and an insulating gate bipolar transistor (IGBT). The switching device of claim 2, wherein: the first relay has a first end electrically connected to the live line of the AC power source, a second end, and a first control signal for receiving the first control signal The second relay has a first end electrically connected to the neutral line output end of the AC power source, a second end, and a control end for receiving the first control signal; Having a first end, a second end, and a control end for receiving the third control signal, the first and second ends of the third relay of the first switch unit are electrically connected to the first relay The second end of the second switch and the live connection of the load, the first and second ends of the third relay of the second switch unit are electrically connected to the second end of the second relay and the load The first switching unit further includes a third controlled rectifier, and the first controlled rectifier is electrically connected in series with each other at the second end of the first relay and the live connection of the load Between and each has one for Receiving a control end of the second control signal, two first diodes are electrically connected in series with each other between the second end of the first relay and the live connection end of the load, the first two poles The respective anodes of the body and the cathodes of the first and third step-controlled rectifiers are electrically connected to each other; and the second switching unit further includes a fourth controlled rectifier, and the second controlled rectifier is electrically connected to each other in series The second end of the second relay is connected to the neutral line of the load, and each has a control end for receiving the second control signal, and two third diodes are electrically connected to each other in series Connected between the second end of the second relay and the neutral line connection end of the load, the respective anodes of the third diodes and the cathodes of the second and fourth controlled rectifiers are electrically connected to each other connection. The switching device of claim 2, wherein: the first relay has a first end electrically connected to the live line of the AC power source, a second end, and a first control signal for receiving the first control signal a second terminal having a first end connected to the neutral line output of the AC power source, a second end, and a control end for receiving the first control signal; the first and the first The two controlled rectifiers each have a cathode, an anode, and a control terminal for receiving the second control signal; the third relays each have a first end, a second end, and a third for receiving the third a control end of the control signal, the first and second ends of the third relay of the first switch unit are electrically connected to the second end of the first relay and the live line end of the load, respectively, the second switch The first and second ends of the third relay of the unit are electrically connected to the second end of the second relay and the neutral line connection end of the load, respectively.