Power supply equipment and uninterruptible power supply

Abstract

The invention discloses power supply equipment and an uninterruptible power supply, and relates to the technical field of power electronics, and the power supply equipment comprises a switching circuit which is connected between a power grid and a load and comprises a plurality of thyristors which are connected in series; the driving module is used for switching on and switching off the thyristors and comprises a transformer and a plurality of driving circuits, the transformer comprises a primary winding and a plurality of secondary windings, and the driving circuits are connected with the thyristors and the secondary windings in a one-to-one correspondence mode; the driving circuit comprises a temperature switch, one end of the secondary winding is connected with a gate pole of the thyristor, the other end of the secondary winding is connected with one end of the temperature switch, the other end of the temperature switch is connected with a cathode of the thyristor, and the temperature switch is switched on when the temperature of the thyristor is smaller than or equal to a preset temperature and switched off when the temperature of the thyristor is larger than the preset temperature. Therefore, the over-temperature protection of the thyristor in the power supply equipment can be realized, and the size and the hardware cost of the power supply equipment can be considered.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power electronics, and particularly relates to a power supply device and an uninterruptible power system. BACKGROUND

[0002] A thyristor is commonly used as a core power control element in an uninterruptible power system (UPS), and the thyristor is used to guarantee the safe and stable operation of a main circuit in a high-voltage and high-power scene by using the characteristics of high voltage resistance, large current bearing and fast on-off of the thyristor, and the power supply reliability of the UPS is the most important performance index.

[0003] In the operation process of the thyristor, the thyristor is easy to be overheated and broken down, and even exploded and damaged due to overheating caused by factors such as process defects, long-term working loss and overcurrent impact in the working process of the thyristor, which not only causes the working failure of the UPS and leads to the shutdown of a load, but also causes a safety accident such as an electrical fire and threatens personal safety. Therefore, it is necessary to measure the temperature of each thyristor in the working process of the UPS, that is, a large number of temperature detection electronic elements need to be arranged in the device, which increases the volume and hardware cost of the UPS. SUMMARY

[0004] Embodiments of the present application provide a power supply device and an uninterruptible power system, which are used to consider the volume and hardware cost of the power supply device when implementing over-temperature protection of a thyristor in the power supply device.

[0005] In a first aspect, the present application provides a power supply device, which comprises a switching circuit and a driving module: the switching circuit is used to be connected between a power grid and a load, and the switching circuit comprises a plurality of thyristors connected in series; the driving module is used to turn on and turn off the plurality of thyristors, and the driving module comprises a transformer and a plurality of driving circuits, the transformer comprises a primary winding and a plurality of secondary windings, the plurality of secondary windings are connected to the plurality of driving circuits in a one-to-one correspondence, and the plurality of driving circuits are connected to the plurality of thyristors in a one-to-one correspondence; the driving circuit comprises a temperature switch, one end of the secondary winding is connected to a gate electrode of the thyristor, the other end of the secondary winding is connected to one end of the temperature switch, the other end of the temperature switch is connected to a cathode of the thyristor, and the temperature switch is used to be turned on when the temperature of the thyristor is less than or equal to a preset temperature, and to be turned off when the temperature of the thyristor is greater than the preset temperature.

[0006] In the embodiment, the temperature switch is arranged in the driving circuit of the thyristor, and the temperature switch is always on when the temperature of the thyristor is less than or equal to the preset temperature and is automatically turned off when the temperature of the thyristor is greater than the preset temperature, so that the temperature switch can turn off the connection between the thyristor and the transformer when the temperature of the thyristor is too high, thereby indirectly determining whether the thyristor is overheated by comparing the actual working state of the thyristor with the theoretical working state of the thyristor. In this way, the temperature data of the thyristor does not need to be obtained to detect the overheating of the thyristor, so that a temperature sensor and a supporting temperature data transmission line do not need to be additionally arranged for each thyristor, thereby reducing the number of electronic components and the wiring complexity of the power supply device, reducing the assembly and debugging workload of the power supply device, and thereby reducing the size of the power supply device and the uninterruptible power supply in which the power supply device is located, and reducing the hardware cost thereof.

[0007] In some embodiments, the power supply device further comprises a controller configured to: control the primary winding and the driving power source to be conductive, so that the plurality of thyristors are conductive; and control the primary winding and the driving power source to be disconnected when one of the plurality of thyristors is turned off, so that the other thyristors except the one thyristor are turned off.

[0008] In the embodiment, when the controller detects that the actual working state of one of the thyristors is in the off state, that is, the temperature of the one thyristor is greater than the preset temperature, the corresponding temperature switch of the one thyristor is automatically turned off, and the one thyristor is automatically turned off, so that the theoretical working state of the one thyristor is different from the actual working state. At this time, the controller controls the primary winding of the transformer and the driving power source to be disconnected, so that the other thyristors except the one thyristor are turned off, thereby avoiding the overheating failure of the other thyristors connected in series and improving the use safety of the power supply device.

[0009] In some embodiments, the power supply device further comprises a plurality of sampling resistors, the plurality of sampling resistors correspond to the plurality of thyristors one by one, and the sampling resistor and the corresponding thyristor are connected in parallel, and the controller is configured to: when the voltage across the sampling resistor corresponding to the one thyristor is greater than zero when the primary winding and the driving power source are conductive, control the primary winding and the driving power source to be disconnected, so that the other thyristors are turned off.

[0010] In the embodiment, when the sampling resistor is connected in parallel with the thyristor, the voltage transformer at both ends of the sampling resistor can reflect the working state of the thyristor, so that, by using the sampling resistor of the inherent thyristor in the power supply device, only a temperature switch needs to be arranged in the driving circuit of the thyristor, and by using the characteristic that the temperature switch is always on when the temperature of the thyristor is less than or equal to a preset temperature and is automatically turned off when the temperature of the thyristor is greater than the preset temperature, the controller can indirectly determine whether the corresponding thyristor has an over-temperature problem based on the detected voltage change at both ends of the sampling resistor, so as to realize temperature detection of the thyristor. In this way, no temperature sensor and supporting temperature data transmission line need to be additionally arranged for each thyristor, the volume of the power supply device is reduced, and the hardware cost thereof is reduced.

[0011] In some embodiments, the temperature switch includes a thermosensitive reed switch or a thermistor.

[0012] In some embodiments, the driving circuit further includes an impedance component, one end of the impedance component is connected with one end of the secondary winding, and the other end of the impedance component is connected with the other end of the secondary winding.

[0013] In the embodiment, when one of the plurality of thyristors is turned off, the impedance component can maintain the voltage of the secondary winding corresponding to the one thyristor stable, so as to avoid impedance abnormality of the driving circuit connected with the secondary winding corresponding to the one thyristor due to the turn-off of the temperature switch, thereby ensuring the working stability of the primary winding of the transformer or the driving circuit in which the other secondary windings are located.

[0014] In some embodiments, the impedance component includes a zener diode, the anode of the zener diode is connected with the other end of the secondary winding, and the cathode of the zener diode is connected with one end of the secondary winding.

[0015] In the embodiment, when the temperature switch of the driving circuit connected with the secondary winding corresponding to the one thyristor is turned off, the zener diode can maintain the voltage of the secondary winding corresponding to the one thyristor stable, that is, the voltage at both ends of the secondary winding can be clamped to a rated zener voltage, thereby suppressing the transient overvoltage of the secondary winding when the temperature switch is turned off, avoiding breakdown of other components or thyristors in the driving circuit, and ensuring the normal working of the primary winding of the transformer or the driving circuit in which the other secondary windings are located.

[0016] In some embodiments, the impedance component includes a first resistor, and the resistance value of the first resistor is greater than the resistance value of the turned-on temperature switch.

[0017] In the embodiment, the current in the driving circuit flows through the circuit where the first resistor is located. The first resistor can be used to divide the voltage of the turned-off thyristor, so as to balance the voltage burden of each thyristor in series, so that when the thyristor is turned off, the voltage is not concentrated on a single thyristor and the secondary winding connected to the single thyristor, thereby ensuring the normal operation of the driving circuit where the other secondary windings are located, so that the thyristors connected to the other secondary windings can still be normally driven to be turned on.

[0018] In some embodiments, the power supply device further comprises a plurality of heat sinks for dissipating heat from the plurality of thyristors, and the temperature switch is embedded in the heat sinks.

[0019] In the embodiment, the heat sinks are used to dissipate heat from the plurality of thyristors, and the temperature switch is embedded in the heat sinks. When the temperature switch is in close contact with the heat sinks by being embedded in the heat sinks, the temperature switch can directly sense the actual temperature of the heat sinks, avoiding environmental temperature interference, and the temperature switch has a smaller sensing error for the temperature of the thyristors, so that the switching action of the thyristors can reflect the true heating state of the thyristors.

[0020] In some embodiments, the driving circuit further comprises a rectifier bridge, a positive electrode of the rectifier bridge being connected to the other end of the secondary winding, and a negative electrode of the rectifier bridge being connected to one end of the secondary winding.

[0021] In the embodiment, when the driving power supply outputs alternating current to the primary winding of the transformer, the alternating current is converted into direct current by the rectifier bridge arranged at the secondary winding of the transformer, so that a forward trigger voltage can be always applied between the gate electrode and the cathode electrode of the thyristor of the secondary winding of the transformer, so as to meet the requirement of trigger conduction of the thyristor.

[0022] In some embodiments, the driving module further comprises a first switch and a capacitor, one end of the capacitor being connected to one end of the primary winding, and the first switch being connected between the other end of the capacitor and the other end of the primary winding.

[0023] In the embodiment, the capacitor is connected in parallel across the primary winding of the transformer. When the driving power supply supplies power to the transformer, the electric energy is first stored in the capacitor. When the transformer drives the thyristor, the capacitor is rapidly discharged through the primary winding, and a large amount of electric energy is released instantaneously, so that a large current required for trigger conduction of the thyristor can be output from the secondary winding side.

[0024] In some embodiments, the driving circuit further comprises a second resistor and a light-emitting diode, one end of the second resistor being connected to one end of the secondary winding, and the light-emitting diode being connected between the other end of the second resistor and the other end of the secondary winding, the light-emitting diode being used to emit light when the thyristor is turned on.

[0025] In the embodiment, the light-emitting diode can emit light when the thyristor is turned on, thereby intuitively prompting the operation and maintenance personnel whether the secondary winding has output and the driving circuit is normally turned on, facilitating the operation and maintenance personnel to quickly judge the working state of the driving circuit, and when the current output by the secondary winding flows through the circuit where the light-emitting diode is located, the second resistor can be used for voltage division and current limiting, so that the light-emitting diode can always work in the rated working current range, thereby avoiding damage of the light-emitting diode due to overcurrent.

[0026] In a second aspect, the embodiment of the present application provides an uninterruptible power supply, which comprises a main circuit, a maintenance bypass and an inverter bypass, the main circuit and the maintenance bypass are used for being connected between a power grid and a load, and the inverter bypass is used for being connected between an energy storage device and the load, the main circuit comprises the power supply device provided in the above embodiment, and the uninterruptible power supply is used for: turning on the power supply device to enable the power grid to supply power to the load through the main circuit; or turning on the maintenance bypass to enable the power grid to supply power to the load through the maintenance bypass; or turning on the inverter bypass to enable the energy storage device to supply power to the load through the inverter bypass.

[0027] In the embodiment, the beneficial effects of the second aspect can refer to the description of the first aspect and any implementation mode thereof, and will not be described here. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 A structure schematic diagram of an uninterruptible power supply provided in the embodiment of the present application;

[0029] Figure 2 A structure schematic diagram of a power supply device provided in the embodiment of the present application;

[0030] Figure 3 A working principle diagram of a temperature switch provided in the embodiment of the present application;

[0031] Figure 4 A structure schematic diagram of another power supply device provided in the embodiment of the present application;

[0032] Figure 5 A structure schematic diagram of a driving circuit provided in the embodiment of the present application;

[0033] Figure 6 A structure schematic diagram of another driving circuit provided in the embodiment of the present application;

[0034] Figure 7 A structure schematic diagram of still another driving circuit provided in the embodiment of the present application;

[0035] Figure 8 A packaging schematic diagram of a temperature switch provided in the embodiment of the present application. DETAILED DESCRIPTION

[0036] With reference to the accompanying drawings, the technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of the present application.

[0037] Before introducing the embodiments related to the present application, some technical terms related to the embodiments of the present application are introduced.

[0038] Silicon controlled rectifier (SCR): also known as thyristor, is a kind of high-power semiconductor device with three PN junctions, which has unidirectional conductivity, can control high power with small power, and can realize microsecond level conduction and turn-off.

[0039] Contact resistance: the resistance generated by the current passing through the contact surface of the contact point of the electronic components such as switches and connectors when the contact point is closed.

[0040] Please refer to Figure 1 , Figure 1 A structure schematic diagram of an uninterruptible power supply 100 provided by an embodiment of the present application is shown in the figure. Figure 1 As shown in the figure, the uninterruptible power supply 100 provided by the embodiment of the present application includes a main circuit 110, a maintenance bypass 120 and an inverter bypass 130.

[0041] In the embodiment, the main circuit 110 is used to be connected between the power grid 210 and the load 300. By turning on the main circuit 110, the uninterruptible power supply 100 converts the alternating current and outputs it to the load 300, so that the power grid 210 supplies power to the load 300 through the main circuit 110. The maintenance bypass 120 is used to be connected between the power grid 210 and the load 300. When the uninterruptible power supply 100 is under maintenance, by turning on the switch K0 in the maintenance bypass 120, the power grid 210 supplies power to the load 300 through the maintenance bypass 120, so as to ensure uninterrupted power supply to the load 300 during maintenance. The uninterruptible power supply 100 is used to provide uninterrupted power supply to the load 300 with high requirements for power supply stability, such as communication equipment, charging piles of electric vehicles, etc.

[0042] In addition, the inverter bypass 130 is used to connect between the energy storage device 220 and the load 300, and the uninterruptible power supply 100 is used to enable the energy storage device 220 to continue to supply power to the load 300 for a period of time when the main circuit 110 fails or the power grid 210 stops supplying power, thereby avoiding power failure of the load 300. For example, when the power grid 210 supplies power, the main circuit 110 of the uninterruptible power supply 100 converts the alternating current output by the power grid 210 and outputs the converted alternating current to the communication device, and when the power grid 210 stops supplying power, the inverter bypass 130 of the uninterruptible power supply 100 continues to supply power to the communication device for a period of time using the power stored by the energy storage device 220, so as to ensure that the communication device can operate normally before the power grid 210 recovers or to enable the user to have sufficient time to save data. The inverter bypass 130 includes an inverter circuit 131, a thyristor SCR, and a three-phase transformer TPT. When the inverter bypass 130 is turned on, the inverter circuit 131 converts the direct current output by the energy storage device 220 into alternating current, and the converted alternating current is transmitted to the three-phase transformer TPT through the turned-on thyristor SCR, and the three-phase transformer TPT converts the alternating current into alternating current that meets the power supply requirements of the load 300.

[0043] In the embodiment, the main circuit 110 of the uninterruptible power supply 100 is provided with a plurality of thyristors SCR connected in series. Since the thyristor SCR has the characteristics of a silicon rectifier device, it can work under high voltage and large current conditions, and its working process can be controlled, and it is a typical small-current control large-current electronic device. Therefore, when the uninterruptible power supply 100 works in a medium-voltage or high-voltage power system, i.e., the working voltage of the main circuit 110 is usually 10 kV or higher, by controlling the turn-on and turn-off of the thyristor SCR, the safe and stable operation of the uninterruptible power supply 100 can be ensured.

[0044] During the working process of the main circuit 110, the thyristor SCR in the main circuit 110 may be overheated due to process defects, long-term working loss, overcurrent impact, and other factors, which may burn out the thyristor SCR, cause the main circuit 110 of the uninterruptible power supply 100 to be interrupted, the load 300 to be shut down, and even cause safety accidents such as electrical fire and threaten personal safety.

[0045] In some embodiments, an optical fiber temperature measurement technology is used, and a sensing optical fiber is laid on the surface of the heat sink of each thyristor SCR to form a contact point with the heat sink of each thyristor SCR, so that the case temperature of each thyristor SCR can be obtained through the sensing optical fiber. At the same time, the instantaneous loss is calculated by combining the working current and on-state voltage, and the junction temperature of each thyristor SCR can be obtained by using parameters such as thermal resistance and heat capacity. In addition, the case temperature and the junction temperature of the thyristor SCR are used as alarm bases to alarm the safe operation of the thyristor SCR. When the case temperature or the junction temperature of the thyristor SCR exceeds a preset threshold, a corresponding alarm signal is sent, so as to realize temperature detection and over-temperature alarm of the thyristor SCR.

[0046] However, although a single optical fiber can cover multiple thyristors SCRs to avoid the complex layout and packaging of setting sensors for each thyristor SCR individually, the laying of the sensing optical fiber still has the problem of high cost, and the sensing optical fiber needs to be matched with special optoelectronic devices such as laser generators, electro-optical modulators, and optical amplifiers during temperature measurement. Not only does it need to be matched with a special sealing structure for use, which leads to a high failure rate of the sensing optical fiber during use, but it also needs to be matched with corresponding control power and control circuit for the above-mentioned optoelectronic devices, which further increases the cost of temperature measurement of the thyristors SCRs in the uninterruptible power supply 100 and increases the packaging volume of the uninterruptible power supply 100.

[0047] To improve the above problems, the embodiments of the present application provide a power supply device and an uninterruptible power supply, which are used to consider the volume and hardware cost of the power supply device when implementing over-temperature protection of the thyristors in the power supply device.

[0048] In some embodiments, the main circuit includes a power supply device 400, as shown in Figure 2 Figure 2 A structural schematic diagram of a power supply device 400 provided by the embodiments of the present application. The power supply device 400 provided by the embodiments of the present application includes a switching circuit 410 and a driving module 420.

[0049] In the present embodiment, the switching circuit 410 is used to be connected between the power grid 210 and the load 300, and the switching circuit 410 includes a plurality of thyristors SCRs connected in series. The switching circuit 410 is used to be turned on when the power grid 210 supplies power to the power supply device 400. Among them, the thyristor SCR has better voltage strength than the field effect transistor and the bipolar transistor. By using a plurality of thyristors SCRs connected in series, the voltage strength of the switching circuit 410 as a whole can be improved, so that the switching circuit 410 can be applied to the scene where the uninterruptible power supply where the power supply device 400 is located works in a medium-voltage or high-voltage power system. In addition, the power supply device 400 provided by the embodiments of the present application can also be applied to a power supply system outside the uninterruptible power supply which uses the thyristor SCR as a switching element.

[0050] ​In some embodiments, the switch circuit 410 includes two groups of multiple thyristors SCR connected in series, and corresponding thyristors SCR between the two groups are connected in anti-parallel, thereby forming two conduction channels with opposite conduction directions in the switch circuit 410, so that the switch circuit 410 can conduct in both directions when the power grid 210 inputs alternating current. In addition, when the power grid 210 outputs three-phase alternating current to the power supply device 400, the power supply device 400 includes three switch circuits 410 and three driving modules 420, the three switch circuits 410 are connected to the three driving modules 420 one by one, each switch circuit 410 corresponds to one phase of the three-phase alternating current, and the driving module 420 is used to control the conduction and turn-off of the corresponding switch circuit 410 to turn on and turn off the alternating current of the corresponding phase.

[0051] In addition, when the driving module 420 is connected to the switch circuit 410, it is used to turn on and turn off the multiple thyristors SCR connected in series in the switch circuit 410, that is, the driving module 420 turns on the thyristors SCR connected in series in the switch circuit 410, so that the main circuit in the uninterruptible power supply is turned on, and the power grid 210 supplies power to the load 300 through the switch circuit 410 turned on in the main circuit.

[0052] In some embodiments, the driving module 420 includes a transformer T and multiple driving circuits 421, the transformer T includes a primary winding and multiple secondary windings. The multiple secondary windings are connected to the multiple driving circuits 421 one by one, the multiple secondary windings share the same core, and when the primary winding inputs a trigger pulse, the magnetic field change is synchronously coupled to the multiple isolated secondary windings, and the multiple secondary windings each form an independent current loop and can be connected to different driving circuits 421. In addition, the multiple driving circuits 421 are connected to the multiple thyristors SCR one by one, the thyristor SCR includes an anode, a cathode, and a gate, the driving circuit 421 is connected between the gate and the cathode of the thyristor SCR, when the driving circuit 421 is turned on, the secondary winding of the transformer T applies a forward trigger voltage between the gate and the cathode of the thyristor SCR through the turned-on driving circuit 421, so that a trigger current is generated between the gate and the cathode, and then the anode and the cathode of the thyristor SCR change from a high-resistance blocking state to a low-resistance conduction state, so that the thyristor SCR is turned on.

[0053] In this embodiment, the driving circuit 421 includes a temperature switch TS, one end of the secondary winding is connected to the gate of the thyristor SCR, the other end of the secondary winding is connected to one end of the temperature switch TS, the other end of the temperature switch TS is connected to the cathode of the thyristor SCR, and the temperature switch TS is used to turn on when the temperature of the thyristor SCR is less than or equal to a preset temperature, and turn off when the temperature of the thyristor SCR is greater than the preset temperature.

[0054] The power supply device 400 also includes a controller ( Figure 2The controller is configured to control the primary winding of the transformer T to be connected to the driving power supply, so that the plurality of thyristors SCR are turned on. When the driving power supply supplies power to the primary winding of the transformer T, the primary winding generates an alternating magnetic field, and the secondary winding generates an alternating voltage matching the turns ratio based on the principle of electromagnetic induction. Since the temperature switch TS in the driving circuit 421 is in a normal on state when the temperature of the thyristor SCR is less than or equal to the preset temperature, the driving circuit 421 connected to the thyristor SCR is turned on, so that the secondary winding can apply a forward trigger voltage between the gate and the cathode of the thyristor SCR through the turned-on driving circuit 421, and drive the thyristor SCR to be turned on. At this time, the current flows from one end of the secondary winding to the gate of the thyristor SCR, and then flows from the cathode of the thyristor SCR to the turned-on temperature switch TS, and finally returns to the other end of the secondary winding, forming a current loop.

[0055] When one of the plurality of thyristors SCR is turned off, since the temperature switch TS in the driving circuit 421 is automatically turned off when the temperature of the thyristor SCR is greater than the preset temperature, the driving circuit 421 connected to the thyristor SCR is turned off, so that the secondary winding cannot drive the thyristor SCR to be turned on through the turned-off driving circuit 421, and the thyristor SCR is automatically turned off. Since the controller outputs a control signal to control the primary winding of the transformer T to be connected to the driving power supply, the theoretical working state of the thyristor SCR corresponding to the control signal is in the on state, but when the controller detects that the actual working state of one of the thyristors SCR is in the off state, i.e., the temperature of one of the thyristors SCR is greater than the preset temperature, the temperature switch TS in the driving circuit 421 corresponding to one of the thyristors SCR is automatically turned off, and one of the thyristors SCR is automatically turned off, so that the theoretical working state corresponding to the control signal of one of the thyristors SCR is different from the actual working state. At this time, the controller controls the primary winding of the transformer T to be disconnected from the driving power supply, so that the other thyristors SCR except one of the plurality of thyristors SCR are turned off, which can avoid over-temperature failure of the other thyristors SCR connected in series, and improve the use safety of the power supply device 400.

[0056] In this embodiment, the temperature switch TS is arranged in the driving circuit 421 of the thyristor SCR, and can be used to sense the temperature of the thyristor SCR when the temperature switch TS is close to or attached to the thyristor SCR. By using the temperature switch TS, which is always on when the temperature of the thyristor SCR is less than or equal to a preset temperature, and is automatically turned off when the temperature of the thyristor SCR is greater than the preset temperature, the controller can indirectly determine whether the thyristor SCR has an over-temperature problem based on the difference between the actual working state and the theoretical working state of the thyristor SCR when the temperature switch TS is turned off, and turn off other thyristors SCR when the actual working state is different from the theoretical working state, thereby achieving over-temperature protection of the power supply device 400 and improving the use safety of the power supply device 400.

[0057] Therefore, the controller does not need to obtain the temperature data of the thyristor SCR to achieve over-temperature detection of the thyristor SCR, so that it is not necessary to additionally arrange a temperature sensor and a matching temperature data transmission line for each thyristor SCR, thereby reducing the number of electronic elements and the wiring complexity of the power supply device 400, reducing the assembly and debugging workload of the power supply device 400, and thereby reducing the size of the power supply device 400 and the uninterruptible power supply in which the power supply device 400 is arranged, and reducing the hardware cost thereof.

[0058] In this embodiment, the temperature switch TS includes a thermal reed switch (TRS) or a thermistor, and can also include other electronic elements that are automatically controlled to be turned on and turned off based on temperature changes, which are not specifically limited herein.

[0059] In some embodiments, as shown in Figure 3 , the temperature switch TS is arranged in the driving circuit 421 of the thyristor SCR, and can be used to sense the temperature of the thyristor SCR when the temperature switch TS is close to or attached to the thyristor SCR. By using the temperature switch TS, which is always on when the temperature of the thyristor SCR is less than or equal to a preset temperature, and is automatically turned off when the temperature of the thyristor SCR is greater than the preset temperature, the controller can indirectly determine whether the thyristor SCR has an over-temperature problem based on the difference between the actual working state and the theoretical working state of the thyristor SCR when the temperature switch TS is turned off, and turn off other thyristors SCR when the actual working state is different from the theoretical working state, thereby achieving over-temperature protection of the power supply device 400 and improving the use safety of the power supply device 400. Figure 3 In this embodiment, the temperature switch of the present application provides a working principle diagram. When the temperature switch of this embodiment includes a thermal reed switch, the thermal reed switch is composed of a magnet 510 and two spring leaves 520.

[0060] In this embodiment, the spring leaf 520 is made of a temperature-sensitive soft iron magnetic material. As the temperature rises, the saturation magnetic flux density of the spring leaf 520 formed by the temperature-sensitive soft iron magnetic material in the thermal reed switch decreases, and the spring leaf 520 will change into a paramagnetic substance when the temperature of the contact object is greater than a preset temperature (determined by the material ratio).

[0061] As shown in Figure 3As shown in (a), when the temperature of the contact object of the thermal reed switch is less than or equal to the preset temperature, the temperature-sensitive soft ferromagnetic material in the thermal reed switch is a ferromagnetic body, forming a magnetic flux. That is, the two reeds 520 in the thermal reed switch are magnetized under the action of the magnetic field, and the two reeds 520 make contact and conduct, thus turning on the thermal reed switch. Furthermore, when conducting, the contact resistance of the thermal reed switch is less than 0.5Ω, which can reduce the conduction loss of the drive circuit when driving the thyristor to conduct when the thermal reed switch is on.

[0062] like Figure 3 As shown in (b), when the temperature of the object contacted by the thermal reed switch is greater than the preset temperature, the temperature-sensitive soft ferromagnetic material in the thermal reed switch transforms into a paramagnetic material, the magnetic flux becomes almost zero, the magnetic field disappears, that is, the two reeds 520 in the thermal reed switch separate and disconnect, causing the thermal reed switch to turn off.

[0063] In this embodiment, by using a thermal reed switch to be attached to or near the thyristor and placing the thermal reed switch in the thyristor's drive circuit, the controller can indirectly determine whether the thyristor has an overheating problem based on the difference between the actual and theoretical operating states of the thyristor when the thermal reed switch is off. This achieves temperature detection of the thyristor, eliminating the need for an additional temperature sensor for each thyristor, reducing the size of the power supply equipment, and lowering the hardware cost of the power supply equipment.

[0064] Please see Figure 4 , Figure 4 This is a schematic diagram of another power supply device 400 provided in an embodiment of this application. The power supply device 400 provided in this embodiment includes the aforementioned switching circuit 410 and drive module 420.

[0065] In this embodiment, the power supply device 400 also includes multiple sampling resistors Rs, each corresponding to a specific thyristor SCR, and the sampling resistors Rs are connected in parallel with their corresponding thyristors SCRs. When the primary winding of the transformer T in the drive module 420 is connected to the drive power supply, if the actual operating state of the thyristor SCR is the same as its theoretical operating state (i.e., both are in the on state), the sampling resistor Rs connected in parallel with the thyristor SCR is approximately short-circuited, and almost no current flows through it, causing the voltage across Rs to approach zero. If the primary winding of the transformer T is connected to the drive power supply, but the actual operating state of the thyristor SCR is off, since the actual operating state of the thyristor SCR differs from its theoretical operating state, current flows through the sampling resistor Rs connected in parallel with the thyristor SCR when the thyristor SCR is open-circuited, causing the voltage across Rs to be greater than zero.

[0066] Based on this, when the primary winding of the transformer T is connected with the driving power supply, if the controller detects that the voltage across the sampling resistor Rs corresponding to one thyristor SCR in the series-connected multiple thyristors is greater than zero, it is determined that the actual working state of the one thyristor SCR is different from the theoretical working state, that is, the temperature switch TS in the driving circuit 421 corresponding to the one thyristor SCR is off, and the one thyristor SCR has an over-temperature problem. At this time, the controller disconnects the primary winding of the transformer T from the driving power supply, so that the other thyristors SCR are all turned off, thereby avoiding over-temperature failure of the other thyristors SCR in series connection.

[0067] In addition, since the sampling resistor Rs for collecting the working voltage (or current) of each thyristor SCR is arranged in the power supply device 400, the controller determines whether the thyristor SCR is turned on, whether there is an over-current problem, etc. by acquiring the voltage data (or current data) of the sampling resistor Rs, which is a basic device for ensuring the safe use of the thyristor SCR. Moreover, the transmission line for transmitting and feeding back the related data of the sampling resistor Rs to the controller is a signal transmission line matched therewith.

[0068] In the present application, by using the existing sampling resistor Rs of the thyristor SCR and the matched signal transmission line in the power supply device 400, only the temperature switch TS needs to be arranged in the driving circuit 421 of the thyristor SCR, and the temperature switch TS is used to sense the temperature of the thyristor SCR. By using the characteristic that the temperature switch TS is always on when the temperature of the thyristor SCR is less than or equal to the preset temperature, and is automatically turned off when the temperature of the thyristor SCR is greater than the preset temperature, the controller can detect that the voltage across the sampling resistor Rs changes significantly when the temperature switch TS is turned off. Therefore, based on the change of the voltage data of the sampling resistor Rs, it can be indirectly judged whether the corresponding thyristor SCR has an over-temperature problem, so that the temperature detection of the thyristor SCR is realized, thereby no additional temperature sensor and matched temperature data transmission line need to be arranged for each thyristor SCR, the number of electronic elements and the wiring complexity of the power supply device 400 are reduced, the assembly and debugging workload of the power supply device 400 is reduced, and thus the volume of the power supply device 400 and the uninterrupted power supply in which the power supply device 400 is located is reduced, and the hardware cost thereof is reduced.

[0069] In some embodiments, as shown in Figure 5 , the driving circuit provided by the present application includes a temperature switch TS. Figure 5 The present application provides a structure schematic diagram of a driving circuit. The driving circuit provided by the present application includes a temperature switch TS.

[0070] In the embodiment, the transformer T includes a primary winding and a plurality of isolated secondary windings corresponding to a plurality of thyristors SCR. A driving circuit is connected between the secondary winding and the thyristor SCR, and one end of the secondary winding is connected to the gate of the thyristor SCR, and the other end of the secondary winding is connected to one end of a temperature switch TS, and the other end of the temperature switch TS is connected to the cathode of the thyristor SCR. The temperature switch TS is used to turn on when the temperature of the thyristor SCR is less than or equal to a preset temperature, and turn off when the temperature of the thyristor SCR is greater than the preset temperature.

[0071] In some embodiments, the driving circuit further includes an impedance component 4211, one end of the impedance component 4211 is connected to one end of the secondary winding, and the other end of the impedance component 4211 is connected to the other end of the secondary winding. That is, when the plurality of isolated secondary windings of the transformer T drive a plurality of thyristors SCR connected in series respectively, and each form an independent current loop, the impedance component 4211 is arranged in the driving circuit connected between each secondary winding and the thyristor SCR.

[0072] When one of the plurality of thyristors SCR is turned off, such as the temperature switch TS in the driving circuit corresponding to one thyristor SCR, which turns off the thyristor SCR when the temperature of the thyristor SCR is greater than the preset temperature, the load characteristic of the driving circuit corresponding to one thyristor SCR changes abruptly, which easily affects the voltage and current fluctuations of the driving circuit of the primary winding or other secondary windings of the transformer T, resulting in the transformer T unable to normally drive other thyristors SCR.

[0073] In the embodiment of the application, by connecting the impedance component 4211 in parallel across each secondary winding, when one of the plurality of thyristors SCR is turned off, the impedance component 4211 can maintain the voltage of the secondary winding corresponding to one thyristor SCR stable, which can avoid the driving circuit connected to the secondary winding corresponding to one thyristor SCR due to the temperature switch TS turned off, resulting in abnormal impedance, thereby ensuring the working stability of the driving circuit of the primary winding or other secondary windings of the transformer T.

[0074] As an embodiment, as shown in FIG. 4, the driving circuit of the transformer T includes a plurality of impedance components 4211 connected in parallel across each secondary winding. Figure 6As shown, the above impedance component 4211 includes a Zener diode TD, the positive electrode of which is connected to the other end of the secondary winding, and the negative electrode of which is connected to one end of the secondary winding. When the temperature switch TS corresponding to the secondary winding connected to the thyristor SCR is turned off, due to the sudden change in the voltage value of the induced voltage at the secondary winding, the Zener diode TD is reversely broken down, but the voltage across the Zener diode TD remains almost unchanged, i.e., the voltage across the secondary winding can be clamped to the rated Zener voltage, thereby quickly suppressing the transient overvoltage of the secondary winding, avoiding the breakdown of other components or thyristors SCR in the drive circuit, and ensuring the normal operation of the primary winding or other secondary windings of the transformer T.

[0075] As an implementation manner, as shown in Figure 7 As shown, the above impedance component 4211 includes a first resistor R1, the resistance value of which is greater than that of the temperature switch TS in the on state. When the temperature switch TS corresponding to the secondary winding connected to the thyristor SCR is turned off, due to the fact that the resistance value of the first resistor R1 is greater than that of the temperature switch TS in the on state, but much smaller than that of the temperature switch TS in the off state, the current in the drive circuit flows through the circuit in which the first resistor R1 is located, and the first resistor R1 can be used to divide the voltage of the thyristor SCR in the off state.

[0076] In the case of multiple thyristors SCR connected in series, for the thyristor SCR in the off state, the voltage division effect of the first resistor R1 can balance the voltage burden of each thyristor SCR connected in series, i.e., even if some thyristors SCR are turned off, the voltage will not be concentrated on a single thyristor SCR and the secondary winding connected thereto, so as to ensure the normal operation of the drive circuit of the other secondary windings, and enable the thyristors SCR connected to the other secondary windings to remain normally driven and turned on.

[0077] In some embodiments, the above drive circuit further includes a rectifier bridge RB, the positive electrode of which is connected to the other end of the secondary winding, and the negative electrode of which is connected to one end of the secondary winding. If the drive power supplies alternating current to the primary winding of the transformer T, the primary winding generates an alternating magnetic field, and based on the principle of electromagnetic induction, the secondary winding of the transformer T induces an alternating voltage matching the turns ratio, i.e., the secondary winding of the transformer T outputs alternating current. By arranging the rectifier bridge RB at the secondary winding, the alternating current is converted into direct current after passing through the rectifier bridge RB, so that a forward trigger voltage can always be applied between the gate and the cathode of the thyristor SCR of the secondary winding of the transformer T, thereby meeting the trigger and turn-on requirements of the thyristor SCR.

[0078] In some embodiments, the driving module further comprises a first switch K1 and a capacitor C, one end of the capacitor C is connected to one end of the primary winding, and the first switch K1 is connected between the other end of the capacitor C and the other end of the primary winding. When the controller controls the first switch K1 connected to the primary winding of the transformer T to be conductive, the electrical energy is first stored in the capacitor C connected to the primary winding of the transformer T, and the capacitor C is discharged rapidly through the primary winding, and a large amount of electrical energy is released instantaneously to meet the large current required for the thyristor SCR to be triggered and turned on. The first switch K1 includes a mechanical switch, a metal-oxide-semiconductor field-effect transistor (MOSFET), an insulated gate bipolar transistor (IGBT), etc., which are not limited in the present application.

[0079] In some embodiments, the driving circuit further comprises a second resistor R2 and a light-emitting diode PD, one end of the second resistor R2 is connected to one end of the secondary winding, and the light-emitting diode PD is connected between the other end of the second resistor R2 and the other end of the secondary winding, i.e. the anode of the light-emitting diode PD is connected to the other end of the second resistor R2, and the cathode of the light-emitting diode PD is connected to the other end of the secondary winding. The light-emitting diode PD is used to emit light when the thyristor SCR is turned on, which can directly indicate to the operation and maintenance personnel whether the secondary winding has output and whether the driving circuit is normally turned on, so as to facilitate the operation and maintenance personnel to quickly judge the working state of the driving circuit. Since the current output by the secondary winding may exceed the rated working current of the light-emitting diode PD when the current flows through the circuit where the light-emitting diode PD is located, the second resistor R2 can be used for voltage division and current limiting to make the light-emitting diode PD work within the rated working current range, thereby avoiding damage to the light-emitting diode PD due to overcurrent.

[0080] In some embodiments, as shown in Figure 8 , the temperature switch TS provided by the present application is packaged as shown in Figure 8 .

[0081] The power supply device comprises a plurality of heat sinks 430, and the plurality of heat sinks 430 and the thyristor SCR are fixedly arranged on a substrate where the power supply device is located through bolts, and the heat sink 430 and the thyristor SCR are arranged through the bolts. The heat sink 430 can efficiently lead out the heat generated by the thyristor SCR during operation, reduce the shell temperature and junction temperature of the thyristor SCR, and avoid overheating and breakdown or life attenuation of the thyristor SCR.

[0082] In the embodiment, the heat sink 430 is arranged at the anode A and the cathode K of the thyristor SCR, the plurality of heat sinks 430 are used to dissipate heat of the plurality of thyristors SCR, and the temperature switch TS is embedded in the heat sink 430. When the temperature switch TS is in close contact with the heat sink 430 by being embedded in the heat sink 430, the temperature switch TS can directly sense the actual temperature of the heat sink 430, avoid the interference of the ambient temperature, and has a smaller sensing error for the temperature of the thyristor SCR, and can better reflect the actual heating state of the thyristor SCR.

[0083] In some embodiments, when the driving circuit is arranged between the gate and the cathode K of the thyristor SCR, the temperature switch TS in the driving circuit is connected with the cathode K of the thyristor SCR. By embedding the temperature switch TS in the heat sink 430 at the cathode K of the thyristor SCR, the temperature switch TS is directly connected with the driving circuit at the cathode K, without the need of using additional wiring, thereby reducing the layout cost of the temperature switch TS. Moreover, when the temperature switch TS is arranged at the anode A directly connected with the high-voltage main circuit, a short circuit fault of the driving circuit is easily caused. By embedding the temperature switch TS in the heat sink 430 at the cathode K of the thyristor SCR, without the need of performing additional high-voltage insulation treatment on the temperature switch TS, the insulation between the temperature switch TS and the anode A of the thyristor SCR can be realized, thereby ensuring the use safety of the temperature switch TS.

[0084] The above merely describes the specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any change or replacement within the technical scope disclosed in the present application should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A power supply device, characterized in that, The power supply equipment includes: A switching circuit for connecting a power grid and a load, the switching circuit comprising a plurality of thyristors connected in series; A drive module is used to turn on and off the plurality of thyristors. The drive module includes a transformer and a plurality of drive circuits. The transformer includes a primary winding and a plurality of secondary windings. The plurality of secondary windings are connected to the plurality of drive circuits one by one, and the plurality of drive circuits are connected to the plurality of thyristors one by one. The driving circuit includes a temperature switch. One end of the secondary winding is connected to the gate of the thyristor, and the other end of the secondary winding is connected to one end of the temperature switch. The other end of the temperature switch is connected to the cathode of the thyristor. The temperature switch is used to turn on when the temperature of the thyristor is less than or equal to a preset temperature, and to turn off when the temperature of the thyristor is greater than the preset temperature.

2. The power supply equipment according to claim 1, characterized in that, The power supply equipment also includes a controller, the controller being used for: Control the primary winding to be connected to the drive power supply, so that the plurality of thyristors are turned on; When one of the plurality of thyristors is turned off, the primary winding is disconnected from the drive power supply, thereby turning off all the other thyristors except the one mentioned above.

3. The power supply equipment according to claim 2, characterized in that, The power supply equipment further includes multiple sampling resistors, each corresponding to one of the multiple thyristors. The sampling resistors are connected in parallel with their corresponding thyristors. The controller is used for: When the primary winding is connected to the driving power supply, if the voltage across the sampling resistor corresponding to one of the thyristors is greater than zero, the primary winding is disconnected from the driving power supply, causing all other thyristors to turn off.

4. The power supply equipment according to claim 1, characterized in that, The temperature switch includes a thermistor reed switch or a thermistor.

5. The power supply equipment according to any one of claims 1 to 4, characterized in that, The driving circuit also includes an impedance component, one end of which is connected to one end of the secondary winding, and the other end of which is connected to the other end of the secondary winding.

6. The power supply equipment according to claim 5, characterized in that, The impedance component includes a Zener diode, the positive terminal of which is connected to the other end of the secondary winding, and the negative terminal of which is connected to one end of the secondary winding.

7. The power supply equipment according to claim 5 or 6, characterized in that, The impedance component includes a first resistor, the resistance of which is greater than the resistance of the temperature switch when it is turned on.

8. The power supply equipment according to any one of claims 1 to 4, characterized in that, The power supply equipment also includes multiple heat sinks, which are used to dissipate heat from the multiple thyristors, and the temperature switch is embedded in the heat sinks.

9. The power supply equipment according to any one of claims 1 to 4, characterized in that, The drive circuit also includes a rectifier bridge, the positive terminal of which is connected to the other end of the secondary winding, and the negative terminal of which is connected to one end of the secondary winding.

10. The power supply equipment according to any one of claims 1 to 4, characterized in that, The drive module also includes a first switch and a capacitor, one end of the capacitor being connected to one end of the primary winding, and the first switch being connected between the other end of the capacitor and the other end of the primary winding.

11. The power supply equipment according to any one of claims 1 to 4, characterized in that, The driving circuit also includes a second resistor and a light-emitting diode. One end of the second resistor is connected to one end of the secondary winding, and the light-emitting diode is connected between the other end of the second resistor and the other end of the secondary winding. The light-emitting diode is used to emit light when the thyristor is turned on.

12. An uninterruptible power supply, characterized in that, The uninterruptible power supply (UPS) includes a main circuit, a maintenance bypass, and an inverter bypass. The main circuit and the maintenance bypass are used to connect between the power grid and the load. The inverter bypass is used to connect between the energy storage device and the load. The main circuit includes the power supply equipment as described in any one of claims 1 to 11. The UPS is used for: The power supply equipment is switched on, allowing the power grid to supply power to the load through the main circuit; or... The maintenance bypass is activated, allowing the power grid to supply power to the load through the maintenance bypass; or... The inverter bypass is activated, allowing the energy storage device to supply power to the load through the inverter bypass.

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