TWI633743B - Power bypass apparatus with current-sharing function and method of controlling the same - Google Patents

Abstract

A power supply bypass device with a current sharing function, comprising at least two bypass switch groups and a control unit. Each bypass switch group includes a controllable switch, a cooling unit, and a temperature detecting unit. The temperature detecting unit is disposed in the heat dissipating unit to detect the temperature value of the controllable switch to generate a temperature detecting signal. The control unit receives the temperature detection signal, and outputs at least two switch control signals and at least two cooling unit control signals according to the temperature detection signal to control at least one of the controllable switches or at least two cooling units through the at least two switch control signals The control signal controls at least one of the cooling units to make the current flowing through the controllable switch the same; thereby, the overall efficiency of the power supply system is improved and the power supply bypass current sharing effect of the high power power system is achieved.

Description

Power supply bypass device with current sharing function and control method thereof

The invention relates to a power supply bypass device and a control method thereof, in particular to a power supply bypass device with a current sharing function and a control method thereof.

Referring to FIG. 1, it is a circuit block diagram of an uninterruptible power system having a bypass current sharing circuit of the related art. The uninterruptible power supply mainly includes an AC-to-DC conversion circuit 91, a DC-to-AC conversion circuit 92, a battery unit 93, and a bypass current sharing circuit 80. The AC-to-DC converter circuit 91 receives the AC input power source Vin, and converts the AC input power source Vin into a DC voltage Vdc, and the DC voltage Vc can be used to charge and store the battery unit 93, so that the battery unit 93 can be used as a backup. The AC-to-DC conversion circuit 91 includes a rectification and power factor correction function for rectifying and power factor correction of the AC input power source Vin. The DC-to-AC conversion circuit 92 receives the DC voltage Vdc and converts the DC voltage Vdc and outputs it as an AC output power source Vout to provide the power required for the back-end load. Therefore, the AC input power source Vin passes through the power conversion path formed by the AC-to-DC converter circuit 91 and the DC-to-AC converter circuit 92, and is converted into an AC output power source Vout.

In general, the bypass current sharing circuit 80 is commonly used in any power supply system that requires bypass conversion. For example, in the case of an uninterruptible power system, when the user wants to operate the uninterruptible power system in the ECO mode, Or under conditions of uninterrupted power system failure, overload or overheating. Furthermore, the bypass current sharing circuit 80 typically uses a thyristor as a bypass switch.

Because of the thyristor, a triode AC semiconductor switch (TRIAC) is taken as an example (hereinafter referred to as TRIAC), which has a negative temperature coefficient (NTC) characteristic, so it is assumed that at least two uninterruptible power supplies are provided. In parallel application of the supplier (hereinafter referred to as UPS), if only TRIAC is used as the power supply bypass of the UPS, the TRIAC of the UPS flowing through the power supply bypass current will increase its impedance value due to the temperature increase. This will cause the current flowing through the power supply bypass to increase again, which will eventually cause a vicious cycle, causing the current to flow through the power supply bypass of the same UPS, causing a thermal runaway condition to be disconnected or faulty, resulting in The effect of the power supply bypass is disintegrated.

Therefore, in order to solve the problem of power supply bypass failure caused by the thermal runaway condition of at least two UPS parallel applications, the TRIAC of the power supply bypass is usually connected to the inductor with a large impedance value. Please refer to FIG. 2A , which is a circuit diagram of a bypass current sharing circuit with series inductance, and the bypass current sharing circuit is applied to a low power UPS parallel application, that is, the bypass current sharing circuit 80 of each UPS has The switch 81, the inductor 82 and the current sensor 83 are controlled. In the present embodiment, the tamper switch 81 is exemplified by a TRIAC. Furthermore, please refer to FIG. 2B, which is a schematic block diagram of parallel application of two low power UPSs. The two UPSs are a first uninterruptible power supply 901 and a second uninterruptible power supply 902, and each UPS includes the bypass current sharing circuit 80, the AC-to-DC conversion circuit 91, and the DC pair. The AC conversion circuit 92 and the battery unit 93.

Since the inductor 82 has a positive temperature coefficient characteristic, and the impedance value of the inductor 82 is designed to be equal or much larger than the impedance value of the tamper switch 81, the power supply bypass equivalent impedance value of each UPS can be regarded as an inductor. 82 dominates the decision, which can weaken the effect caused by the negative temperature coefficient of the switch 81. Further, according to the total output current value I of the power supply bypass of each UPS sensed by each current sensor 83, the touch switch 81 and/or the second switch of the first uninterruptible power supply 901 can be further controlled. The conduction angle of the power-off power supply 902 of the power-off power supply 902 is such that the current sharing of the power supply bypass of the two small power UPSs can be achieved.

However, in order to overcome the thermal runaway condition, the inductor with a large impedance value is added, which not only increases the component cost, the circuit integrated body, but also increases the power consumption, so that the overall efficiency of the uninterruptible power system is lowered. To achieve the purpose of improving efficiency by operating the uninterruptible power system in the energy-saving mode.

Please refer to FIG. 3A, which is a circuit diagram of a bypass current sharing circuit with series inductance. The main difference between FIG. 3A and FIG. 2A is that the former bypass current sharing circuit is applied to a higher power UPS. That is, a single UPS has a large power, and the bypass current sharing circuit 80 has two branch circuits in which the switch 81 and the inductor 82 are connected in series, and a current sensor 83, and the complete two high-power UPSs are applied in parallel. See Figure 3B for details.

Whether it is a low power UPS parallel application (as shown in Figure 2B) or a high power UPS parallel application (as shown in Figure 3B), each UPS bypass current sharing circuit 80 has only one current sensor 83 To sense the total output current value I of the power supply bypass of each UPS. In other words, for a high power UPS parallel application, it is not possible to sense only the current in the series branch of the tamper switch 81 and the inductor 82. Therefore, for a high-power UPS parallel application, it is not possible to individually control the conduction angle of the corresponding tamper switch 81 based on the total output current value I of each UPS sensed by the current sensor 83, so that large The power UPS is applied in parallel to the current sharing control between the respective control switches 81 and the series of branches of the inductor 82. In addition, not only the UPS is applied in parallel, but any power system that requires bypass conversion has the above problems.

An object of the present invention is to provide a power supply bypass device with a current sharing function, which solves the problem that the power running-off causes the power supply bypass failure, the overall efficiency of the power supply system is lowered, and the high-power power system cannot be controlled by the current sharing.

To achieve the foregoing object, the power supply bypass device with current sharing function of the present invention comprises at least two bypass switch groups and a control unit. At least two bypass switch groups are correspondingly applied to at least two power supplies, and each of the bypass switch groups includes a controllable switch, a cooling unit, and a temperature detecting unit. The controllable switch is disposed on the heat dissipation unit. The cooling unit is correspondingly disposed on the heat dissipation unit, and is controlled according to a cooling capacity of the cooling unit to provide heat control of the controllable switch. The temperature detecting unit is correspondingly disposed on the heat dissipating unit, and detects a temperature value of the controllable switch to generate a temperature detecting signal with information of a temperature value. The control unit is coupled to the at least two bypass switch groups and receives the temperature detection signal. The control unit outputs at least two switch control signals corresponding to at least two bypass switch groups and at least two cooling unit control signals according to the temperature detection signal, so as to control at least one switch conduction period of the controllable switch through the at least two switch control signals, Or controlling the cooling capacity of at least one of the cooling units through at least two cooling unit control signals to make the current flowing through the controllable switch the same.

In one embodiment, the switch-on period of at least one of the controllable switches is full-cycle conduction.

In one embodiment, the controllable switch has a negative temperature coefficient characteristic.

In one embodiment, the controllable switch is a bidirectional controllable switch, and at least one of the switch control signals correspondingly controls a trigger angle of the bidirectional controllable switch to control a switch on period of at least one of the controllable switches.

In one embodiment, the controllable switch is a group of step-controlled rectifiers formed by reverse-parallel coupling of two step-controlled rectifiers, and at least one of the switch control signals correspondingly controls a trigger angle of the group of controlled rectifiers to control the controllable switch At least one of the switch conduction periods.

In an embodiment, when the switch on period of the bidirectional controllable switch is decreased, the current flowing through the bidirectional controllable switch is reduced; when the switch on period of the bidirectional controllable switch is increased, the flow is bidirectionally controllable. The current of the switch increases.

In an embodiment, when the switch conduction period of the step-controlled rectifier group decreases, the current flowing through the step-controlled rectifier group decreases; when the switch conduction angle of the step-controlled rectifier group increases, the current flowing through the step-controlled rectifier group increases. .

In an embodiment, the cooling unit is a fan unit, and the cooling unit control signal controls a rotational speed conduction period of the fan unit.

In an embodiment, when the rotation period of the fan unit increases, the cooling capacity of the fan unit increases, the temperature of the controllable switch decreases, and the current flowing through the controllable switch decreases; when the rotation period of the fan unit decreases, The cooling capacity of the fan unit is reduced, the temperature of the controllable switch is increased, and the current flowing through the controllable switch is increased.

By the proposed power supply bypass device with current sharing function, it is possible to prevent the power runaway from causing the power supply bypass failure, improve the overall efficiency of the power supply system, and realize the power supply bypass current sharing effect of the high power power system.

Another object of the present invention is to provide a power supply bypass device with a current sharing function, which solves the problem that the power running-off causes the power supply bypass failure, the overall efficiency of the power supply system is lowered, and the high-power power system cannot be uniformly current-controlled.

To achieve the foregoing object, the power supply bypass device with current sharing function of the present invention comprises at least two bypass switch groups and a control unit. At least two bypass switch groups are correspondingly applied to at least two power supplies, and each of the bypass switch groups includes a first controllable switch, a second controllable switch, a cooling unit, and a temperature detecting unit. The first controllable switch is disposed on the heat dissipation unit. The second controllable switch is disposed on the heat dissipation unit and coupled to the first controllable switch in parallel. The cooling unit is correspondingly disposed on the heat dissipation unit, and is controlled according to a cooling capability of the cooling unit to provide heat dissipation between the first controllable switch and the second controllable switch. The temperature detecting unit is correspondingly disposed on the heat dissipating unit, and detects temperature values of the first controllable switch and the second controllable switch to generate a temperature detecting signal with information of a temperature value. The control unit is coupled to the at least two bypass switch groups and receives the temperature detection signal. The control unit outputs at least two switch control signals corresponding to at least two bypass switch groups and at least two cooling unit control signals according to the temperature detection signal to control the first controllable switch and the second controllable switch through the at least two switch control signals. At least one of the switch conducting periods, or controlling the cooling capacity of at least one of the cooling units through the at least two cooling unit control signals to cause the current flowing through the first controllable switch and the second controllable switch to be the same.

In an embodiment, the switch-on period of at least one of the first controllable switch and the second controllable switch is full-cycle conduction.

In an embodiment, the first controllable switch and the second controllable switch have a negative temperature coefficient characteristic.

In one embodiment, the first controllable switch and the second controllable switch are two-way controllable switches, and at least one of the switch control signals controls the trigger angle of the two-way controllable switch to control the first controllable switch. And a switch on period of at least one of the second controllable switches.

In one embodiment, the first controllable switch and the second controllable switch are a group of controlled rectifiers formed by reverse parallel coupling of two step-controlled rectifiers, and at least one of the switch control signals correspondingly controls the group of the controlled rectifiers A firing angle to control a switching on period of at least one of the first controllable switch and the second controllable switch.

By the proposed power supply bypass device with current sharing function, it is possible to prevent the power runaway from causing the power supply bypass failure, improve the overall efficiency of the power supply system, and realize the power supply bypass current sharing effect of the high power power system.

Still another object of the present invention is to provide a current sharing control method that solves the problem that the heat runaway causes a power supply bypass failure, the overall efficiency of the power supply system is lowered, and the high power power system cannot be uniformly current controlled.

In order to achieve the foregoing, the current sharing control method proposed by the present invention is applied to a power supply bypass device of at least two power supplies, and the power supply bypass device includes at least two bypass switch groups and a control unit, and each bypass switch group includes The controllable switch on the heat dissipating unit and the cooling unit and the temperature detecting unit corresponding to the heat dissipating unit, the current sharing control method includes: each temperature detecting unit detects a temperature value of each controllable switch; each temperature detecting unit generates a temperature detection signal of the temperature value information; the control unit receives the temperature detection signal; and the control unit outputs at least two switch control signals corresponding to the at least two bypass switch groups and at least two cooling unit control signals according to the temperature detection signal to transmit The at least two switch control signals control the switch on period of at least one of the controllable switches, or control the cooling capacity of at least one of the cooling units through the at least two cooling unit control signals to make the current flowing through the controllable switch the same.

In one embodiment, the switch-on period of at least one of the controllable switches is full-cycle conduction.

In one embodiment, the controllable switch has a negative temperature coefficient characteristic.

By the proposed current sharing control method, it is possible to prevent the heat runaway from causing the power supply bypass failure, improve the overall efficiency of the power supply system, and realize the power supply bypass current sharing effect of the high power power system.

In order to further understand the technology, the means and the effect of the present invention in order to achieve the intended purpose, refer to the following detailed description of the invention and the accompanying drawings. The detailed description is to be understood as illustrative and not restrictive.

The technical content and detailed description of the present invention will be described below in conjunction with the drawings.

Referring to FIG. 4A, it is a circuit block diagram of a first embodiment of a power supply bypass device with a current sharing function according to the present invention, wherein the first embodiment is applied in parallel for a plurality of low power power supplies, and The current sharing of the power supply is achieved by controlling the on-period of the bypass switch group (described later). Taking the uninterruptible power supply as an example, as shown in FIG. 1, the power supply bypass device 100 (hereinafter referred to as "power bypass device 100") having a current sharing function is applied to at least two (low power) uninterrupted power supplies. A power supply for equalizing the power supply bypass path of at least two uninterruptible power supplies. The power supply bypass device 100 includes at least two bypass switch groups 10, 20 and a control unit 30. In this embodiment, two bypass switch groups, that is, the first bypass switch group 10 and the second bypass switch group 20 are taken as an example for description. In addition, in order to focus on the description of the power supply bypass device 100, other circuits of the uninterruptible power supply will not be presented in the drawings. Related art can be seen in conjunction with FIGS. 1, 2B and 3B.

The first bypass switch group 10 includes a first controllable switch 11 and a first temperature detecting unit 12. The first temperature detecting unit 12 is correspondingly disposed on the first controllable switch 11 for detecting the temperature of the first controllable switch 11, that is, the first temperature value T1, and generating the first temperature having the first temperature value T1 information. The signal St1 is detected. The second bypass switch group 20 includes a second controllable switch 21 and a second temperature detecting unit 22. The second temperature detecting unit 22 is correspondingly disposed on the second controllable switch 21 for detecting the temperature of the second controllable switch 21, that is, the second temperature value T2, and generating a second temperature having the second temperature value T2 information. Detection signal St2. The foregoing "corresponding setting" means that the temperature detecting unit 12, 22 can be used to detect the temperature of the corresponding controllable switches 11, 21 in any form such as coupling, proximity or co-packaging, and the aforementioned so-called "controllable" "Identifies that the first controllable switch 11 and the second controllable switch 21 are permeable to control their conduction period, or otherwise controlled. In this embodiment, the first controllable switch 11 and the second controllable switch 21 can be a triode AC semiconductor switch (TRIAC), and a silicon controlled rectifier (SCR) reverse parallel coupling. The first temperature detecting unit 12 and the second temperature detecting unit 22 can be implemented as a heat sensitive element, but the invention is not limited thereto.

In this embodiment, the first controllable switch 11 is disposed on the first heat dissipating unit 11 ′, wherein the first heat dissipating unit 11 ′ may be a heat dissipating fin, a heat dissipating module or other component or device having a heat dissipating function. The invention is not limited thereto. Therefore, the first temperature detecting unit 12 can obtain the first temperature value T1 information by directly or indirectly sensing the temperature of the first heat radiating unit 11'. Similarly, the second controllable switch 21 is disposed on the second heat dissipating unit 21', and the second temperature detecting unit 22 can directly or indirectly sense the temperature of the second heat dissipating unit 21' to obtain the second temperature value. T2 information.

The control unit 30 can be coupled to the first temperature detecting unit 12 and the second temperature detecting unit 22, or can receive the first temperature detecting signal St1 and the receiving signal transmitted by the first temperature detecting unit 12 in a communication manner. The second temperature detecting signal St2 transmitted by the second temperature detecting unit 22, that is, the control unit 30 obtains the temperature of the first controllable switch 11 according to the first temperature detecting signal St1, and the second temperature detecting signal according to the second temperature detecting signal St1 St2 can obtain the temperature of the second controllable switch 21.

The control unit 30 is further coupled to the first controllable switch 11 of the first bypass switch group 10 and the second controllable switch 21 of the second bypass switch group 20. The control unit 30 outputs at least two control signals corresponding to at least two bypass switch groups according to the first temperature detection signal St1 and the second temperature detection signal St2, for example, outputting the first switch control signal Sc1 and the second switch control signal Sc2. The first switch control signal Sc1 is used to control the first controllable switch 11 of the first bypass switch group 10, and the second switch control signal Sc2 is used to control the second controllable switch 21 of the second bypass switch group 20. In an embodiment, the first switch control signal Sc1 and the second switch control signal Sc2 can be used to control a conduction period of at least one of the first controllable switch 11 and the second controllable switch 21, that is, the first controllable switch 11 The on period can be controlled by the first switch control signal Sc1, and the on period of the second controllable switch 21 is not controlled by the second switch control signal Sc2; or the on period of the second controllable switch 21 can be the second switch The control signal Sc2 is controlled, and the on period of the first controllable switch 11 is not controlled by the first switch control signal Sc1. Thereby, the first current value I1 flowing through the first controllable switch 11 is controlled to be the same as the second current value I2 of the second controllable switch 21, and a plurality of (two in this embodiment) uninterruptible power supply are achieved. The current sharing effect of the power bypass path.

In this embodiment, the control unit 30 is not limited to one controller as shown in FIG. 4A, and can be applied to an uninterruptible power supply system architecture well known to those skilled in the art. For example, if the first bypass switch The group 10 and the second bypass switch group 20 are disposed in the same module, and the controller unit 30 can be implemented using one controller. On the other hand, if the first bypass switch group 10 and the second bypass switch group 20 are respectively located in two uninterruptible power supply devices, the two uninterruptible power supply devices respectively have one controller, which can be provided by two The controllers communicate with one another or with another controller of an external uninterruptible power supply system, whereby the control unit 30 is implemented.

Referring to FIG. 4B, it is a circuit block diagram of a second embodiment of a power supply bypass device with a current sharing function according to the present invention. The greatest difference between the second embodiment and the first embodiment is that the former (ie, the first The second embodiment) achieves the current sharing of the uninterruptible power supply by controlling the cooling capacity of the cooling unit, wherein the cooling unit can be a fan or a water-cooled motor system, etc., and the cooling is controlled by controlling the speed of the fan or the speed of the water-cooled motor. ability. For convenience of description, the cooling unit of the second embodiment takes a fan unit as an example, but is not limited thereto, and is described below.

The first bypass switch group 10 further includes a first fan unit 13. The first fan unit 13 is correspondingly disposed on the first heat dissipating unit 11 ′ provided with the first controllable switch 11 , that is, the wind flow provided by the first fan unit 13 may cover the range of the first heat dissipating unit 11 ′, and according to the The rotational speed of a fan unit 13 is controlled to provide heat dissipation from the first controllable switch 11. Likewise, the second bypass switch group 20 further includes a second fan unit 23. The second fan unit 23 is correspondingly disposed on the second heat dissipating unit 21 ′ provided with the second controllable switch 21 , that is, the wind flow provided by the second fan unit 23 may cover the range of the second heat dissipating unit 21 ′, and according to the The rotational speed of the two fan units 23 is controlled to provide heat dissipation by the second controllable switch 21.

Specifically, the control unit 30 outputs the first fan control signal Spwm1 and the second fan control signal Spwm2 corresponding to the two bypass switch groups 10, 20 according to the first temperature detection signal St1 and the second temperature detection signal St2 to respectively control The first fan unit 13 and the second fan unit 23. In this embodiment, if the first fan unit 13 and the second fan unit 23 are pulse width modulation (PWM) type fans, the first fan control signal Spwm1 and the second fan control signal Spwm2 may be pulses. The width modulation signal, and controlling the rotational speed on period of at least one of the first fan unit 13 and the second fan unit 23 by changing a duty cycle of the pulse width modulation signal. As for the switch-on period of the aforementioned controllable switch and the speed-on period of the fan unit, the two current sharing control will be described in detail later.

Referring to FIG. 5A, which is a circuit block diagram of a third embodiment of a power supply bypass device with a current sharing function according to the present invention, wherein the third embodiment is applied in parallel for a plurality of high power power supplies. Taking an uninterruptible power supply as an example, as shown in FIG. 1, a power supply bypass device 200 (hereinafter referred to as "power bypass device 200") having a current sharing function is applied to at least two (high power) uninterrupted power supplies. A power supply for equalizing the power supply bypass path of at least two uninterruptible power supplies. The power supply bypass device 200 includes at least two bypass switch groups 10, 20 and a control unit 30. In this embodiment, the two bypass switch groups, that is, the first bypass switch group 10 and the second bypass switch group 20 are taken as an example for description. In addition, in order to focus on the description of the power supply bypass device 200, other circuits of the uninterruptible power supply will not be presented in the drawings, and related art can be seen in conjunction with FIGS. 1, 2B, and 3B.

The first bypass switch group 10 includes a first controllable switch 111, a second controllable switch 112, and a first temperature detecting unit 12. The second controllable switch 112 is coupled in parallel to the first controllable switch 111. The first temperature detecting unit 12 is correspondingly disposed on the first controllable switch 111 and the second controllable switch 112, and detects the first temperature value T1 of the first controllable switch 111 and the second controllable switch 112 to generate The first temperature detection signal St1 of the information of the first temperature value T1.

The second bypass switch group 20 includes a third controllable switch 211, a fourth controllable switch 212, and a second temperature detecting unit 22, wherein the fourth controllable switch 212 is coupled in parallel with the third controllable switch 211. The second temperature detecting unit 22 is correspondingly disposed on the third controllable switch 211 and the fourth controllable switch 212, and detects the second temperature value T2 of the third controllable switch 211 and the fourth controllable switch 212 to generate The second temperature detecting signal St2 of the information of the second temperature value T2.

In this embodiment, the first controllable switch 111 and the second controllable switch 112 are disposed on the first heat dissipation unit 11 ′, wherein the first heat dissipation unit 11 ′ can be a heat dissipation fin, a heat dissipation module or the like. Functional elements or devices are not intended to limit the invention. Therefore, the first temperature detecting unit 12 can obtain the first temperature value T1 by directly or indirectly sensing the temperature of the first heat radiating unit 11'. Similarly, the third controllable switch 211 and the fourth controllable switch 212 are disposed on the second heat dissipating unit 21 ′, and the second temperature detecting unit 22 can directly or indirectly sense the temperature of the second heat dissipating unit 21 ′. And obtaining a second temperature value T2. In this embodiment, the first temperature value T1 detected by the first temperature detecting unit 12 is the temperature of the first heat dissipating unit 11 ′, which may be regarded as the first controllable switch 111 and the second controllable switch 112 . The same temperature. Similarly, the second temperature value T2 detected by the second temperature detecting unit 22 is the temperature of the second heat radiating unit 21', and can be regarded as the same temperature of the third controllable switch 211 and the fourth controllable switch 212.

In another embodiment, the first controllable switch 111 and the second controllable switch 112 are respectively disposed on different heat dissipating units, that is, one controllable switch is correspondingly disposed on one heat dissipating unit, so A temperature detecting unit group having two temperature detecting units respectively detects the temperatures of the two heat dissipating units and performs current sharing control on the detected temperatures. Similarly, the temperature detection and current sharing control of the third controllable switch 211 and the fourth controllable switch 212 respectively disposed on different heat dissipation units are also applicable. Furthermore, the temperature detection and the current sharing control are similar to the temperature detection and current sharing control of the plurality of controllable switches corresponding to one heat dissipation unit. Therefore, the third embodiment shown in FIG. 5A can be used later. The description of the analogy is known.

The control unit 30 can be coupled to the first temperature detecting unit 12 and the second temperature detecting unit 22, or can receive the first temperature detecting signal St1 and the receiving signal transmitted by the first temperature detecting unit 12 in a communication manner. The second temperature detecting signal St2 transmitted by the second temperature detecting unit 22, that is, the control unit 30 can obtain the temperatures of the first controllable switch 111 and the second controllable switch 112 according to the first temperature detecting signal St1, according to The temperature of the third controllable switch 211 and the fourth controllable switch 212 can be obtained by the second temperature detecting signal St2.

The control unit 30 is further coupled to the first controllable switch 111 and the second controllable switch 112 of the first bypass switch group 10 and the third controllable switch 211 and the fourth controllable switch 212 of the second bypass switch group 20 . The control unit 30 outputs at least two control signals corresponding to at least two bypass switch groups according to the first temperature detection signal St1 and the second temperature detection signal St2, for example, outputting the first switch control signal Sc1 and the second switch control signal Sc2. The first switch control signal Sc1 is used to control the first controllable switch 111 and the second controllable switch 112 of the first bypass switch group 10, respectively, and the second switch control signal Sc2 is used to control the second bypass switch group 20, respectively. The third controllable switch 211 and the fourth controllable switch 212. In an embodiment, the first switch control signal Sc1 and the second switch control signal Sc2 can be used to control the first controllable switch 111 and the second controllable switch 112, and the third controllable switch 211 and the fourth controllable switch 212 are at least The conduction period of one of the first controllable switch 111 and the second controllable switch 112 can be controlled by the first switch control signal Sc1, and the third controllable switch 211 and the fourth controllable switch 212 can be turned on. The cycle is not controlled by the second switch control signal Sc2, that is, the trigger angle thereof is not changed; or the conduction period of the third controllable switch 211 and the fourth controllable switch 212 can be controlled by the second switch control signal Sc2, and the The conduction period of one of the controllable switch 111 and the second controllable switch 112 is not controlled by the first switch control signal Sc1, that is, the trigger angle is not changed. Thereby, the first current value I11 flowing through the first controllable switch 111, the second current value I12 flowing through the second controllable switch 112, the third current value I21 flowing through the third controllable switch 211, and the flow are controlled. The fourth current value I22 of the fourth controllable switch 212 is the same, in other words, the total output current of the power supply bypass of each of the high-power uninterruptible power supplies can be controlled, that is, the first total current value I1 and the second total The current value I2 is the same, where I11=I12=I21=I22=1/2×I1=1/2×I2, and the power supply bypass of a plurality of high-power uninterruptible power supply devices (two in this embodiment) is achieved. The current sharing effect of the path.

Referring to FIG. 5B, it is a circuit block diagram of a fourth embodiment of a power supply bypass device with a current sharing function according to the present invention, wherein the fourth embodiment and the third embodiment have the greatest difference in the former (ie, the first The fourth embodiment) achieves the current sharing of the uninterruptible power supply by controlling the cooling capacity of the cooling unit, wherein the cooling unit can be a fan or a water-cooled motor system, etc., and the cooling is controlled by controlling the speed of the fan or the speed of the water-cooled motor. Capabilities, such as increasing the cooling capacity by controlling fan speed, or increasing the flow rate by increasing the water-cooled motor speed to increase cooling capacity. For convenience of description, the cooling unit of the fourth embodiment is exemplified by a fan unit, but is not limited thereto, and is explained as follows.

The first bypass switch group 10 further includes a first fan unit 13. The first fan unit 13 is correspondingly disposed on the first heat dissipating unit 11 ′, which is provided with the first controllable switch 111 and the second controllable switch 112 , that is, the wind flow provided by the first fan unit 13 may cover the first heat dissipating unit 11 ′. The range is controlled according to the rotation speed of the first fan unit 13 to provide heat dissipation of the first controllable switch 111 and the second controllable switch 112. Likewise, the second bypass switch group 20 further includes a second fan unit 23. The second fan unit 23 is correspondingly disposed on the second heat dissipating unit 21 ′, which is provided with the third controllable switch 211 and the fourth controllable switch 212 , that is, the wind flow provided by the second fan unit 23 may cover the second heat dissipating unit 21 ′. The range is controlled according to the rotation speed of the second fan unit 23 to provide heat dissipation of the third controllable switch 211 and the fourth controllable switch 212.

Specifically, the control unit 30 outputs the first fan control signal Spwm1 and the second fan control signal Spwm2 corresponding to the two bypass switch groups 10, 20 according to the first temperature detection signal St1 and the second temperature detection signal St2 to respectively control The first fan unit 13 and the second fan unit 23. In this embodiment, if the first fan unit 13 and the second fan unit 23 are pulse width modulation type fans, the first fan control signal Spwm1 and the second fan control signal Spwm2 may be pulse width modulation (pulse width modulation). The PWM) signal, and controlling the rotational speed conduction period of at least one of the first fan unit 13 and the second fan unit 23 by changing a duty cycle of the pulse width modulation signal. As for the switch-on period of the aforementioned controllable switch and the speed-on period of the fan unit, the two current sharing control will be described in detail later.

FIG. 6A is a block diagram showing the switch-on period feedback control of the controllable switch of the power supply bypass device with the current sharing function, wherein the temperature feedback control includes a limiting unit 41, a controller unit 42, The controllable switch 43 and the temperature detecting unit 44 constitute a closed-loop negative feedback control. 4A, since two low-power uninterruptible power supplies have two controllable switches, namely a first controllable switch 11 and a second controllable switch 21, the embodiment corresponding to FIG. 4A may have The temperature feedback control of the two groups, wherein one set of control plants, the controllable switch 43 can be the first controllable switch 11, and the other set of controlled objects can be the second controllable switch 21. Similarly, one set of temperature detecting unit 44 may be the first temperature detecting unit 12, and the other set of temperature detecting unit 44 may be the second temperature detecting unit 22. In this embodiment, the feedback control block can be implemented by the control unit 30 in an analogous or digital manner. Similarly, the embodiment shown in FIG. 5A is also applicable, and details are not described herein again.

In addition, since the embodiment is used to control the on period of at least one of the first controllable switch 11 and the second controllable switch 21, the temperature feedback control includes a limiting unit 41, or a limiter, which can be used to limit the adjustment. One of the first controllable switch 11 and the second controllable switch 21 will be described in more detail below.

In the temperature control, the average value of the first temperature value T1 of the first controllable switch 11 and the second temperature value T2 of the second controllable switch 21 can be set as the temperature reference value Tref, that is, Tref=1/2 (T1+T2), but not limited to this, you can also use different weights to generate temperature reference values. The first temperature value T1 detected by the first temperature detecting unit 12 is set to a temperature feedback value Tfb, that is, Tfb=T1.

Referring to FIG. 7 , it is a schematic diagram of the switch on period control of the controllable switch of the present invention. When the temperature feedback value Tfb is greater than the temperature reference value Tref, the average value is set as the temperature reference value Tref, that is, T1>1/2 (T1+T2), the temperature reference value Tref and the temperature feedback value Tfb. The difference, that is, the temperature error value Terr is a negative value, the controller unit 42 controls to decrease the switching on period of the first controllable switch 11, for example, to control the firing angle of the first controllable switch 11 (such as the angle α shown in FIG. 7) To reduce the switch on period, the first current value I1 flowing through the first controllable switch 11 is reduced. When the first current value I1 decreases, the first temperature value T1 of the first controllable switch 11 (ie, the temperature feedback value Tfb) decreases. Here, the controller unit 42 can utilize any control law well known to those skilled in the art, such as a Proportional-Integral controller or a Fuzzy control.

When the temperature feedback value Tfb is less than or equal to the temperature reference value Tref, that is, T1 <= 1/2 (T1 + T2), the temperature error value Terr is a positive value or zero, and the controller unit 42 does not output the control amount to change the first The firing angle of the controllable switch 11.

In summary, through the negative feedback control of the closed loop, the temperature error value Terr can be controlled to be zero, that is, the temperature feedback value Tfb is equal to the temperature reference value Tref, thereby causing the first current flowing through the first controllable switch 11 The value I1 is the same as the second current value I2 of the second controllable switch 21 (shown in FIG. 4A), and reaches the power supply bypass device 100 of the plurality of (two in this embodiment) uninterruptible power supply. Current sharing control.

As described above, the limiting unit 41 is configured to limit the adjustment of one of the first controllable switch 11 and the second controllable switch 21. In this embodiment, the limiting unit 41 can be a simple limiter that outputs zero when the temperature error value Terr is positive. In other words, the switch conduction period is adjusted only when the temperature error value Terr is negative. For example, when the first temperature value T1 of the first controllable switch 11 is greater than the temperature reference value Tref, that is, T1>1/2 (T1+T2), the difference between the temperature reference value Tref and the temperature feedback value Tfb, That is, the temperature error value Terr is a negative value, and the controller unit 42 controls to decrease the switch on period of the first controllable switch 11, for example, to control the firing angle of the first controllable switch 11 (the angle α shown in FIG. 7) to be reduced. The small switch is turned on, causing the first current value I1 flowing through the first controllable switch 11 to decrease. In contrast, the second temperature value T2 of the second controllable switch 21 is smaller than the temperature reference value Tref, that is, T2<1/2(T1+T2), and the temperature error value Terr is a positive value, so the output of the limiting unit 41 is Zero, the controller unit 42 does not adjust the switch-on period of the second controllable switch 21, that is, maintains full-cycle conduction. Therefore, in summary, the limiting unit 41 is configured to limit at least one of the first controllable switch 11 and the second controllable switch 21 to be fully cycled to provide at least one bypass path.

In addition, the control of the switch on period of the controllable switch is also applicable to the four controllable switches respectively disposed on four different heat dissipation units, and the conditions corresponding to the four temperature detection units are used, the difference is corresponding to four The temperature value detected by the temperature detecting unit (ie, the first temperature value T1 of the first controllable switch 111, the second temperature value T2 of the second controllable switch 112, and the third temperature value of the third controllable switch 211 T3 and the fourth temperature value T4) of the fourth controllable switch 212 can provide four sets of temperature feedback control, correspondingly controlling four controllable switches, that is, the first controllable switch 111, the second controllable switch 112, and the The three controllable switches 211 and the fourth controllable switch 212.

Similar to the control of the two low-power uninterruptible power supplies of FIG. 4A described above, the difference is that in the temperature control, the first temperature value T1 of the first controllable switch 111 and the second controllable switch 112 may be The average value of the second temperature value T2, the third temperature value T3 of the third controllable switch 211, and the fourth temperature value T4 of the fourth controllable switch 212 is set to the temperature reference value Tref, that is, Tref=1/4 (T1+T2) +T3+T4), but without this limitation, different weights can be used to generate the temperature reference. Corresponding to the four controllable switches, using four sets of temperature feedback control, for the temperature feedback control of the first controllable switch 111, the first temperature value T1 is set to the temperature feedback value Tfb, ie Tfb=T1 The difference between the temperature reference value Tref and the temperature feedback value Tfb is used to adjust the switch on period of the first controllable switch 111; for the temperature feedback control of the third controllable switch 211, the third temperature value T3 is set For the temperature feedback value Tfb, that is, Tfb=T3, the difference between the temperature reference value Tref and the temperature feedback value Tfb is used to adjust the switch conduction period of the third controllable switch 211; the remaining second controllable switch 112 and the fourth The control switch 212 is not described again for the same control principle. Therefore, in this embodiment, not only the current sharing effect of the power supply bypass path of a single high-power uninterruptible power supply can be realized, that is, the first current value I11 is the same as the second current value I12, and the third current value I21 The current value of each branch of the first current value I11, the second current value I12, the third current value I21, and the fourth current value I22 may be controlled to be identical to the fourth current value I22. In other words, it is also possible to control the total output current of the power supply bypass of each high-power uninterruptible power supply, that is, the first total current value I1 is the same as the second total current value I2, and multiple units are reached (two in this embodiment). The current sharing effect of the power supply bypass path of the uninterruptible power supply.

Please refer to FIG. 6B , which is a block diagram showing the rotational speed feedback control of the fan unit of the power supply bypass device with the current sharing function. Different from the switch-on period feedback control of the controllable switch shown in FIG. 6A, FIG. 6B is the feedback control of the speed of the fan unit. In the present invention, the control of the two current sharing is performed in an alternative manner, that is, when the speed of the fan unit is selected as the current sharing control, the control of the switch conduction period of the controllable switch is not performed, and vice versa. Of course.

Similar to the switch-on period feedback control of the controllable switch shown in Fig. 6A, the controlled object in Fig. 6B is the fan unit 43'. 4B, since the two low-power uninterruptible power supplies have two controllable switches, namely the first controllable switch 11 and the second controllable switch 21, the embodiment corresponding to FIG. 4A may have Temperature feedback control for both groups.

As shown in FIG. 4B, the control unit 30 learns the first controllable according to the first temperature detection signal St1 and the second temperature detection signal St2. When the first temperature value T1 of the switch 11 is higher than the second temperature value T2 of the second controllable switch 21, the control unit 30 can control the duty cycle of the pulse width modulation signal of the output first fan control signal Spwm1. Increasing, and controlling the duty cycle of the pulse width modulation signal of the output second fan control signal Spwm2 to decrease the rotation speed of the first fan unit 13, and lowering the rotation speed of the second fan unit 23, thus making the first temperature value T1 is decreased, and the second temperature value T2 is correspondingly increased. After the feedback control, the first temperature value T1 and the second temperature value T2 can be made the same, thereby controlling the first current value flowing through the first controllable switch 11. I1 is the same as the second current value I2 of the second controllable switch 21, and achieves the current sharing effect of the power supply bypass paths of the plurality of power supply units (two in this embodiment). In the above control process, the first switch control signal Sc1 outputted by the control unit 30 for controlling the first controllable switch 11 and the second switch control signal Sc2 for controlling the second controllable switch 21 are all fully turned on, that is, triggered. The angle α is zero degrees.

In addition, the limiting unit 41, or the limiter, is configured to control the conduction period of at least one of the first fan unit 13 and the second fan unit 23, since the principle and operation of the limiting unit 41 are in the foregoing description of FIG. 6A. It has been disclosed in detail, so it will not be described here. When the control unit 30 knows that the first temperature value T1 of the first controllable switch 11 is higher than the second temperature value T2 of the second controllable switch 21, the design of the limiting unit 41 is transparent, so that the control unit 30 only controls The duty cycle of the pulse width modulation signal of the output first fan control signal Spwm1 is increased to increase the rotation speed of the first fan unit 13 (at this time, the rotation speed of the second fan unit 23 remains unchanged), so that the first temperature is made The value T1 is decreased; or, the control unit 30 controls only the duty cycle of the pulse width modulation signal of the output second fan control signal Spwm2 to decrease the rotation speed of the second fan unit 23 (at this time, the first fan unit 13) The rotation speed of the second temperature value T2 is increased by the feedback control, and the first temperature value T1 can be made the same as the second temperature value T2 by the feedback control, whereby the flow of the first controllable switch 11 can also be controlled. The first current value I1 is the same as the second current value I2 of the second controllable switch 21, and the current sharing effect of the power supply bypass paths of the plurality of (two in this embodiment) uninterruptible power supply is achieved.

FIG. 6B is a block diagram showing the feedback control of the fan unit speed. However, the two units in this embodiment are taken as an example, and the first temperature value T1 and the second temperature value T2 can be simply determined. The size is used to adjust the corresponding fan speed, and those skilled in the art should understand that any control method that achieves the same temperature can be applied. The fan control signal is not limited to the pulse width modulation signal. If the fan speed is a voltage regulation type, the fan control signal is a voltage control signal, and those skilled in the art should understand that different fans have different speed control signals.

Please refer to FIG. 8, which is a flowchart of the current sharing control method of the present invention. The current sharing control method is applied to a power supply bypass device of at least two power supplies. The power bypass device includes at least two bypass switch groups and a control unit, and each bypass switch group includes a controllable switch and a temperature detecting unit. The controllable switch has a negative temperature coefficient characteristic. For example, the controllable switch can be a bidirectional controllable switch (TRIAC), and at least one control signal controls a trigger angle of the bidirectional controllable switch to change at least one of the controllable switches. The conduction period of the person is not limited by this. In addition, the controllable switch may also be a group of controlled rectifiers formed by reverse parallel coupling of two step-controlled rectifiers, and at least one control signal controls a firing angle of the group of controlled rectifiers to change a conduction period of at least one of the controllable switches .

The current sharing control method includes the following steps: First, each temperature detecting unit detects a temperature value of each controllable switch (S11). Each temperature detecting unit includes a first temperature detecting unit and a second temperature detecting unit for instantly measuring the temperature values of the first controllable switch and the second controllable switch. Wherein, each controllable switch can be disposed on a corresponding heat dissipation unit. Furthermore, the power supply bypass device further includes a cooling unit corresponding to the heat dissipation unit, that is, the first controllable switch corresponds to the first cooling unit, and the second controllable switch corresponds to the second cooling unit, and according to the first cooling unit The cooling capacity of the second cooling unit is controlled to provide heat dissipation of the first controllable switch and the second controllable switch.

Then, each temperature detecting unit generates a temperature detecting signal having temperature value information (S12), and the control unit receives the temperature detecting signal (S13). That is, the control unit can obtain the temperature of the first controllable switch and the temperature of the second controllable switch according to the temperature detection signal.

Finally, the control unit outputs at least two switch control signals and at least two cooling unit control signals according to the temperature detection signal to control a switch conduction period of at least one of the first controllable switch and the second controllable switch, or control the first cooling The cooling capability of at least one of the unit and the second cooling unit is such that the current flowing through the first controllable switch and the second controllable switch is the same (S14). In other words, the control unit can selectively control the two current sharing modes, that is, the switch-on period feedback control of the controllable switch and the cooling capacity control of the cooling unit. For the switch-on period feedback control of the controllable switch, the control unit reduces the conduction angle of the controllable switch according to the control, and reduces the current flowing through the controllable switch, thereby controlling the flow through the first controllable switch The current value is the same as the current value of the second controllable switch, achieving a current sharing effect of the power supply bypass path of the power supply. For the cooling capacity control of the cooling unit, the control unit increases the cooling capacity of the control cooling unit, reduces the current flowing through the controllable switch, or reduces the cooling capacity of the control unit to reduce the current flowing through the controllable switch. Therefore, the current value flowing through the first controllable switch is controlled to be the same as the current value of the second controllable switch, and the current sharing effect of the power supply bypass path of the power supply can also be achieved.

In summary, the present invention has the following features and advantages:

1. By adopting the power supply bypass device and the current sharing control method with current sharing function, it can prevent the power running-off from causing power supply bypass failure, improve the overall efficiency of the power supply system, and realize power supply bypass of the high-power power system. Current sharing effect.

2. The current sharing control mechanism of the switch-on period of the controllable switch and the cooling capacity of the cooling unit can more flexibly adapt to the actual operation requirements and select a suitable current sharing control mode.

The above is only the detailed description and the drawings of the preferred embodiments of the present invention, but the invention is not limited thereto, and is not intended to limit the scope of the present invention. The embodiments of the present invention and the similar variations of the scope of the present invention are intended to be included in the scope of the present invention, and any skilled person can easily change or modify them in the field of the present invention. Both can be covered in the following patent scope of this case.

100‧‧‧Power supply bypass device with current sharing function

200‧‧‧Power supply bypass device with current sharing function

10‧‧‧First Bypass Switch Set

20‧‧‧Second Bypass Switch Set

30‧‧‧Control unit

11‧‧‧First controllable switch

21‧‧‧Second controllable switch

111‧‧‧First controllable switch

112‧‧‧Second controllable switch

211‧‧‧ third controllable switch

212‧‧‧4th controllable switch

11’‧‧‧First heat sink unit

21’‧‧‧second heat sink unit

12‧‧‧First temperature detection unit

22‧‧‧Second temperature detection unit

T1‧‧‧ first temperature value

T2‧‧‧ second temperature value

T3‧‧‧ third temperature value

T4‧‧‧ fourth temperature value

St1‧‧‧First temperature detection signal

St2‧‧‧Second temperature detection signal

St3‧‧‧ third temperature detection signal

St4‧‧‧ fourth temperature detection signal

Sc1‧‧‧ first switch control signal

Sc2‧‧‧Second switch control signal

Sc3‧‧‧ third switch control signal

Sc4‧‧‧fourth switch control signal

Spwm1‧‧‧First fan control signal

Spwm2‧‧‧Second fan control signal

I1‧‧‧First total current value

I2‧‧‧second total current value

I11‧‧‧First current value

I12‧‧‧second current value

I21‧‧‧ third current value

I22‧‧‧ fourth current value

41‧‧‧Restriction unit

42‧‧‧control unit

43‧‧‧Controllable switch

44‧‧‧Temperature detection unit

43’‧‧‧Fan unit

Tref‧‧‧ temperature reference value

Tfb‧‧‧temperature feedback value

Terr‧‧‧ temperature error value

‧‧‧‧trigger angle

80‧‧‧Bypass current sharing circuit

81‧‧‧矽Control switch

82‧‧‧Inductors

83‧‧‧ Current Sensor

901‧‧‧First uninterruptible power supply

902‧‧‧Second continual power supply

91‧‧‧AC to DC converter circuit

92‧‧‧DC to AC conversion circuit

93‧‧‧ battery unit

Vin‧‧‧AC input power

Vout‧‧‧AC output power supply

Vdc‧‧‧ DC voltage

I‧‧‧Total output current value

S11~S14‧‧‧Steps

Figure 1: Circuit block diagram of an uninterruptible power system having a bypass current sharing circuit of the related art.

2A is a circuit diagram of a bypass current sharing circuit having a series inductance in the related art.

2B is a circuit block diagram of the bypass current sharing circuit with series inductance of FIG. 2A applied to a low power uninterruptible power system.

3A is a circuit diagram of a bypass current sharing circuit having a series inductance in the related art.

FIG. 3B is a circuit block diagram of the bypass current sharing circuit with series inductance of FIG. 3A applied to a high power uninterruptible power system.

4A is a circuit block diagram showing a first embodiment of a power supply bypass device with a current sharing function according to the present invention.

4B is a circuit block diagram showing a second embodiment of a power supply bypass device with a current sharing function according to the present invention.

FIG. 5A is a circuit block diagram of a third embodiment of a power supply bypass device with a current sharing function according to the present invention.

FIG. 5B is a circuit block diagram of a fourth embodiment of a power supply bypass device with a current sharing function according to the present invention.

FIG. 6A is a block diagram showing the switch-on period feedback control of the controllable switch of the power supply bypass device with the current sharing function of the present invention.

6B is a block diagram showing the rotational speed feedback control of the fan unit of the power supply bypass device with the current sharing function of the present invention.

Fig. 7 is a schematic view showing the control of the on-period of the switch of the controllable switch of the present invention.

8 is a flow chart of a method for current sharing control of the present invention.

Claims (17)

A power supply bypass device with a current sharing function, comprising: at least two bypass switch groups correspondingly applied to at least two power supply devices, each of the bypass switch groups comprising: a controllable switch disposed on a heat dissipation unit; The cooling unit is correspondingly disposed on the heat dissipating unit, and is controlled according to the cooling capacity of the cooling unit to provide heat dissipation of the controllable switch; and a temperature detecting unit corresponding to the heat dissipating unit, and detecting the controllable switch a temperature detection value to generate a temperature detection signal having the information of the temperature value; and a control unit coupled to the at least two bypass switch groups and receiving the temperature detection signals; wherein the control unit is configured according to the And an equal temperature detection signal, outputting at least two switch control signals corresponding to at least two bypass switch groups and at least two cooling unit control signals, to control a switch conduction period of at least one of the controllable switches through the at least two switch control signals, Or controlling, by the at least two cooling unit control signals, a cooling capability of at least one of the cooling units to flow through the controllable opening The same current. The power supply bypass device with current sharing function according to claim 1, wherein the switch-on period of at least one of the controllable switches is full-cycle conduction. A power supply bypass device having a current sharing function as described in claim 2, wherein the controllable switches have a negative temperature coefficient characteristic. The power supply bypass device with current sharing function according to claim 3, wherein each of the controllable switches is a bidirectional controllable switch, and at least one of the switch control signals controls the two-way controllable The firing angle of the switch to control the switching period of at least one of the controllable switches. The power supply bypass device with current sharing function according to claim 3, wherein each of the controllable switches is a group of controlled rectifiers formed by reverse parallel coupling of two step-controlled rectifiers, and the switch controls At least one of the signals correspondingly controls a firing angle of the group of controlled rectifiers to control a switching on period of at least one of the controllable switches. The power supply bypass device with current sharing function according to claim 4, wherein when the switch on period of the bidirectional controllable switch is decreased, the current flowing through the bidirectional controllable switch is reduced; When the switch on period of the controllable switch increases, the current flowing through the bidirectional controllable switch increases. The power supply bypass device with current sharing function according to claim 5, wherein when the switching on-period of the controlled rectifier group is reduced, the current flowing through the controlled rectifier group is reduced; when the controlled rectifier is used As the switch's on-period increases, the current flowing through the group of controlled rectifiers increases. The power supply bypass device with current sharing function according to claim 1, wherein the cooling unit is a fan unit, and the cooling unit control signal controls a speed conduction period of the fan unit. The power supply bypass device with a current sharing function according to claim 8, wherein when the rotation period of the fan unit increases, the cooling capacity of the fan unit increases, and the temperature of the controllable switch decreases. The current flowing through the controllable switch is reduced; when the rotational speed conduction period of the fan unit is decreased, the cooling capacity of the fan unit is reduced, the temperature of the controllable switch is increased, and the current flowing through the controllable switch is increased. A power supply bypass device with a current sharing function, comprising: at least two bypass switch groups correspondingly applied to at least two power supply devices, each of the bypass switch groups comprising: a first controllable switch disposed on a heat dissipation unit a second controllable switch is disposed on the heat dissipating unit and coupled to the first controllable switch in parallel; a cooling unit correspondingly disposed on the heat dissipating unit, and controlled according to cooling capacity of the cooling unit, to provide The first controllable switch and the second controllable switch dissipate heat; and a temperature detecting unit corresponding to the heat dissipating unit, and detecting a temperature value of the first controllable switch and the second controllable switch, a temperature detection signal for generating information having the temperature value; and a control unit coupled to the at least two bypass switch groups and receiving the temperature detection signals; wherein the control unit detects the signals according to the temperature And outputting at least two switch control signals corresponding to at least two bypass switch groups and at least two cooling unit control signals to control the first available through the at least two switch control signals Controlling a switching period of at least one of the switches and the second controllable switches, or controlling, by the at least two cooling unit control signals, a cooling capability of at least one of the cooling units to flow through the first controllable switches The currents of the second controllable switches are the same. The power supply bypass device of the current sharing function of claim 10, wherein the switch-on period of at least one of the first controllable switch and the second controllable switch is full-cycle conduction. The power supply bypass device with current sharing function according to claim 11, wherein the first controllable switch and the second controllable switch have a negative temperature coefficient characteristic. The power supply bypass device with current sharing function according to claim 12, wherein each of the first controllable switch and the second controllable switch is a bidirectional controllable switch, and the switch control signals are at least One controls the trigger angle of the two-way controllable switch to control the switch-on period of at least one of the first controllable switch and the second controllable switch. The power supply bypass device with current sharing function according to claim 12, wherein each of the first controllable switch and the second controllable switch is formed by reverse parallel coupling of two step-controlled rectifiers. Controlling the rectifier group, and at least one of the switch control signals correspondingly controls a firing angle of the group of controlled rectifiers to control a switching on period of at least one of the first controllable switch and the second controllable switch. A current sharing control method is applied to a power supply bypass device of at least two power supplies, the power supply bypass device includes at least two bypass switch groups and a control unit, and each of the bypass switch groups includes a heat dissipation unit disposed on a heat dissipation unit a controllable switch and a cooling unit and a temperature detecting unit corresponding to the heat dissipating unit, the current sharing control method includes: each of the temperature detecting units detecting a temperature value of each of the controllable switches; each of the temperature detecting The measuring unit generates a temperature detecting signal having the information of the temperature value; the control unit receives the temperature detecting signals; and the control unit outputs at least two corresponding at least two bypass switch groups according to the temperature detecting signals And a switch control signal and at least two cooling unit control signals for controlling a switch conduction period of at least one of the controllable switches through the at least two switch control signals, or controlling at least one of the cooling units through the at least two cooling unit control signals The cooling capacity is such that the current flowing through the controllable switches is the same. The current sharing control method of claim 15, wherein the switch-on period of at least one of the controllable switches is full-cycle conduction. The current sharing control method of claim 16, wherein the controllable switches have a negative temperature coefficient characteristic.