WO2014106469A1

WO2014106469A1 - High-voltage direct-current power supply system

Info

Publication number: WO2014106469A1
Application number: PCT/CN2014/070075
Authority: WO
Inventors: 沈亚斌
Original assignee: 浙江中碳科技有限公司
Priority date: 2013-01-06
Filing date: 2014-01-03
Publication date: 2014-07-10
Also published as: CN103066684A

Abstract

A high-voltage direct-current power supply system comprises a high-voltage direct-current power supply, a standby alternating-current power supply and an alternating/direct-current switch output unit for interlocking and switching the high-voltage direct-current power supply and the standby alternating-current power supply and then outputting it to electric equipment. The high-voltage direct-current power supply and the standby alternating-current power supply input dually, output a high-voltage direct current, and output an alternating current by the alternating/direct-current switch output unit as well; at the same time, the high-voltage direct-current power supply and the standby alternating-current power supply in the system have the effect of mutual backup. The high-voltage direct-current power supply system improves the reliability of power supply.

Description

High voltage DC power supply system

Technical field

The invention relates to a power supply and an uninterruptible power supply technology, in particular to a high voltage direct current power supply and a direct current power supply distribution system. Background technique

With the continuous advancement of financial, securities trading centers, customs, government and other units, the shrinking of traditional services and related electrical equipment supporting traditional services has brought about rapid expansion of data services and new related equipment. The power supply to these devices is still powered by a traditional AC uninterruptible power system (UPS). With the rapid growth of transformation business and value-added services, the communication UPS power supply model has become more and more serious in terms of security, reliability and economy in these unit systems, mainly in the following aspects:

High energy consumption. Since the inverter is used in the AC UPS, the battery pack is connected to the front stage of the inverter, and there are many power conversion links, which results in low efficiency. In order to ensure the safety and reliability of the equipment, the current 1 UPS parallel backup system or 2+1 parallel redundant backup system is basically used in the AC UPS power system, which further reduces the system efficiency. Since the UPS is a whole equipment, considering the later development plan, the UPS system construction must be in place at the beginning of the construction of the equipment room, but the development of the business in actual use is a gradual process, which makes the UPS average use efficiency lower. For the above reasons, the average efficiency of AC UPS systems is generally only 50%.

Low safety and reliability. In the AC UPS power system, the reliability of the UPS power supply can be greatly improved by the redundancy technology for a single device, but for the entire UPS power supply system, there are many single point of failure points of the system that cannot be backed up, such as Synchronous parallel boards, static switches, output switches, etc., these single point of failure points may cause the entire power supply system to "blackout". In addition, the battery pack is connected to the front stage of the inverter. Once the inverter fails, the entire power supply system can be "blackout".

Online maintenance and expansion are difficult. Since the AC UPS expansion involves the synchronization of the frequency, voltage, phase sequence, phase, and waveform of the AC, unlike the DC system, only the voltage is concerned. Parameters. Therefore, every online expansion of the AC UPS is an arduous risk operation. It may even be impossible to expand the UPS due to the upgrade and replacement of the UPS manufacturer's own products. As a result, the UPS equipment cannot be replaced when it fails.

Construction investment costs are large. With the growth of business and the rapid expansion of new related equipment, a large number of new AC UPS systems need to be built each year according to the existing equipment power supply mode. The cost of investment and construction is very high, especially in important scenes involving core networks, important business platforms, and VIP customer business. From the perspective of security, the imported UPS system is often used, which further increases the construction cost.

As early as in the 1990s, China's computer power supply fully realized switching power supply, and was the first to complete the electrical equipment, program-controlled switches, communications, power detection equipment power and control equipment power. Most of the devices now have a switching power supply inside. When the input is AC, the direction of the rectifier bridge is alternated. After rectification, it is converted into a fluctuating high-voltage DC, and then passed through.

The DC/DC circuit changes to a low-voltage DC that can work normally with CPUs, LEDs, and various electronic components. When the input is high-voltage direct current, the rectifier bridge is unidirectionally turned on, and the conduction direction is unchanged. At this time, a stable high-voltage direct current is obtained at the rear end of the rectifier bridge, and the voltage is reduced to CPU and LED after being changed by the DC/DC circuit. And low-voltage DC power that can work normally with various electronic components. Therefore, as long as a suitable DC voltage is input to the switching power supply, the switching power supply can work normally.

We know that when the AC power is 220V, the actual peak voltage is 311V, which requires the voltage rating of the component to be higher than the peak voltage. Therefore, the DC voltage of 270V we chose is lower than the highest voltage when AC is working, which is beneficial to the voltage safety and reliability of components.

When the input is AC 220V, its equivalent DC voltage is 220V (lower considering the power factor). When the power of the consumer is constant, according to Ohm's law, the voltage rises and the current drops. When 270V DC is input, the voltage rises and the current decreases to 0.81 times AC. The calculation formula of the calorific value: Ql = KxPxRxT, assuming that the input resistance R of the switching power supply is constant, the heat generated by the switching power supply is 270V DC input: Q2 = Kx0.81Ix0.81IxRxT = 0.656Q1. Where K is the heat conversion coefficient, T For unit time. It is known from the calculation results that the rectifier diode R does not change when the switching power supply is operated for a long time, and the heat generated during the DC input operation is about 1/2 of the heat generated when the AC input is operated. In practical applications, depending on the volt-ampere characteristics of the diode, the rectifier diode is The equivalent resistance at DC input is much smaller than the equivalent resistance R at AC input. Therefore, the amount of heat generated by the switching power supply during actual operation is far less than 1 /2 of the AC input.

Therefore, for the existing switching power supply, the high-voltage DC power supply is indeed better than the AC power supply in terms of energy saving, efficiency improvement, and safety reliability.

In recent years, with the continuous development of technology, various new types of precision electrical equipment have been widely used, and higher requirements have been placed on the safety and reliability of power supplies. With the development of power and power supply technologies, new high-voltage DC power supply systems have emerged. Compared with traditional UPS power supply, the new high-voltage DC power supply system has obvious advantages in terms of safety and reliability, energy saving rate, maintainability and construction cost, and has promoted the use of high-voltage DC power supply system in the data center, replacing the traditional UPS power supply.

However, with the continuous expansion of the application fields of the new high-voltage DC power supply system, the power equipment is more and more complicated, and some new technical problems are encountered. The equipment with switching power supply supports high-voltage DC power supply, but the equipment of non-switching power supply cannot be used. With high voltage DC power supply, only AC power can be used. Therefore, even if the high-voltage DC power supply has obvious advantages, it cannot be applied to all power-consuming places, and it is difficult to take advantage of the high-voltage DC power supply.

At the same time, in the event of a power failure failure of the high-voltage DC power supply and the battery pack is exhausted, the power-consuming equipment will be in a "blackout" state. If there is another backup power supply, you can quickly switch to the backup power supply to restore the power supply through the switching device.

In view of the above two reasons, to promote high-voltage DC power supply to other application areas, and to take advantage of high-voltage DC power supply, we need to develop a new type of high-voltage DC power supply system, suitable for any power use, to meet all power equipment. Power supply requirements. The high-voltage DC system provides direct current while outputting alternating current. At the same time, high-voltage direct current and alternating current are used as backup power sources, which further improves the reliability of the system power supply. Summary of the invention

The object of the present invention is to provide a novel high voltage DC power supply system. The system can output DC power, and can switch output AC power as needed. It can make high voltage DC power supply suitable for most applications, with obvious energy saving effect, high safety and reliability, simple maintenance and low investment cost. In order to achieve the above object, the present invention adopts the following technical solutions: including a high-voltage DC power supply, a standby AC power supply, and an AC-DC switching output unit for outputting the high-voltage DC power supply and the standby AC power supply to each other after being interlocked and switched to the power-consuming equipment.

The high-voltage DC power supply has a nominal voltage of 240V, an actual voltage of 270V, and an operating voltage range of 204V to 292V, which is continuously adjustable.

Further, the AC/DC switching unit includes a DC input end and an AC input end, the DC input end is connected to the output end of the high voltage DC power source, and the AC input end is connected to the standby AC power output end; the output end of the AC/DC switching output unit has a The selection switch with interlock function, the AC/DC switching output unit can output DC power to the switching power supply device through the switching device in the case of AC/DC dual input, and the AC power can be output through the switching device for the non-switching power supply device. At the same time, when the high-voltage DC power supply fails, the standby AC power can be output to the powered device through the switching device.

Further, the high voltage direct current power source includes an alternating current input unit, a rectifier module, and a power storage group.

Among them: 1) AC input unit, including manual/automatic switching device and AC monitoring unit for switching dual AC power input (mains and generator), connecting two AC power inputs to the input of the rectifier module; 2 Rectifier module, for providing high-voltage DC power supply, the output end of the rectifier module is divided into two parallel circuits, one is connected to the DC input end of the AC-DC switching output unit, the other is connected to the battery pack; 3) The battery pack is used for rectification When the module is not working, it supplies power to the powered device through the AC/DC switching output unit.

Further, the AC monitoring unit is used for measuring the electrical signals of the two input and the AC bus, and can also output the control signal of the input switching device according to the two input states.

The AC monitoring unit includes a test CPU, a display interface, and a detection circuit for measuring three-phase voltage, current, and frequency. The outputs of the respective detection circuits are connected to the input of the detection CPU. The measured voltage, current and frequency and other electrical signals can be displayed on the display interface, and sound and light alarm signals and control signals can be emitted at the same time.

Further, the rectifier module is configured to rectify the alternating current into direct current, and the output voltage is continuously adjustable from 204V to 292V. The rectifier module can also charge or discharge the battery; the rectifier module has a current sharing function and has a sleep function in cooperation with the monitoring system. The rectifier module includes at least one rectifying unit, and each rectifying unit includes a main circuit, a control circuit, and an auxiliary power circuit.

The main circuit includes a lightning protection unit, an EMC/EMI circuit, an AC filter circuit, a power conversion circuit, a rectifier circuit, a DC-DC conversion circuit, and a DC filter output circuit. After the three-phase AC input is passed through the lightning protection unit and the EMC/EMI circuit, AC filtering is performed; then the power conversion circuit is used to rectify the output; the output is output to the DC-DC conversion circuit, and finally the desired DC power is output.

The control circuit includes an input overvoltage and undervoltage protection unit, a current limiting protection circuit, an output overvoltage protection circuit, a short circuit protection circuit, a voltage stabilization loop, a sampling circuit, a PFC unit, and a PMW control unit. The PMW control unit collects the signals of the input overvoltage and undervoltage protection unit, the current limiting protection circuit, the output overvoltage protection circuit, the short circuit protection circuit, and the voltage stabilization loop, and summarizes them into the power conversion circuit. The voltage regulation loop collects information from the sampling circuit. The sampling circuit, the short circuit protection circuit, the output overvoltage protection circuit, and the current limiting protection circuit all collect information from the DC filter output circuit in the main circuit. The corresponding information of the AC filter circuit in the main circuit is sent to the input overvoltage and undervoltage protection unit and the PFC unit, and the information input into the overvoltage protection unit is also sent to the PFC unit.

The auxiliary power circuit provides the necessary power for the control circuit.

Further, the battery pack includes a battery management unit and at least one set of batteries. As a backup power of the high-voltage DC power supply, the battery pack is directly connected to the battery pack connection end of the DC bus, and is used for continuously supplying power to the power-consuming equipment when the rectifier module fails to work;

When the two AC input power failures or the rectifier module fails, the battery pack does not need to invert the DC power into AC power, and continuously supplies power to the electrical equipment.

The battery management unit includes a processor, a voltage measuring circuit and a temperature detecting circuit. The input ends of the processor are respectively connected to the output ends of the voltage measuring circuit and the temperature detecting circuit, and the voltage and temperature of each group of batteries are collected in real time.

Further, the standby AC power source is used as a backup power source for the high voltage DC power supply system to output an alternating current to the power device. The standby AC power source can be a mains or UPS, and its output is connected to the input of the AC-DC switching unit.

The alternate AC power source also includes an AC monitoring unit for measuring the state of the alternate AC power input. The AC monitoring unit includes a detection CPU, an AC voltage measuring circuit and an AC current measuring circuit, and an output of the AC voltage measuring circuit and the AC current measuring circuit are both connected to the detection CPU input terminal. Connected.

The AC/DC switching output unit further includes an AC circuit breaker for switching the AC input, a DC circuit breaker for switching the DC input, a miniature circuit breaker for switching the output, and a power distribution detecting unit for monitoring the working state of the AC DC switching output unit, and the miniature circuit breaker. The utility model has a mechanical interlocking device; the power distribution detecting unit comprises a voltage measuring circuit, a current measuring circuit and an insulation detecting circuit.

The measuring end of the voltage measuring circuit and the measuring end of the current measuring circuit are all connected with the output end of the AC/DC switching output unit; the output end of the AC/DC switching output unit is provided with a leakage current sensor, and the detecting end of the insulation detecting circuit and the AC/DC The output of the leakage current sensor in the output of the switching output unit is connected.

The insulation detecting circuit further comprises an insulation detecting processor, wherein the leakage current sensor is a soft magnetic core, and the input end of the insulation detecting processor is connected to the output end of the leakage current sensor, and a ground fault occurs at any one of the output ends of the AC/DC switching output unit. , timely transmit the generated insulation information to the monitoring system.

Further, the system further comprises a monitoring system, and the monitoring system is respectively connected with the AC monitoring unit, the rectifier module, the battery management unit, the standby AC monitoring unit and the power distribution detecting unit, and reads and transmits all working data of the high voltage DC power supply system. Information and control commands.

The monitoring system includes a display module and a system operation management unit, and the output of the system operation management unit is connected to the input end of the display module. The display module is used to display all the data information of the system and obtain the user's input to the system operation.

The most obvious feature of the present invention is: The present invention provides a high-voltage DC power supply and a standby AC power supply dual input, output high-voltage direct current, and can output AC power through the AC-DC switching output unit, so that the high-voltage DC power supply system can be applied to most of the Application area. At the same time, the high-voltage DC power supply and the standby AC power supply in the system have mutual backup functions. When the DC power supply fails and is powered off, you can quickly switch to the standby AC power through the AC/DC switching unit to continue to supply power to the device. Users do not need to make any modifications to existing electrical equipment, and they can use DC power supply, which greatly improves the safety and reliability of power supply while reducing energy consumption. DRAWINGS

1 is a schematic diagram of a power supply system of the present invention; 2 is a block diagram showing the overall structure of a power supply system according to the present invention;

3 is a schematic diagram of an AC input unit in a power supply system of the present invention;

4 is a structural block diagram of a rectifier module in a power supply system according to the present invention;

FIG. 5 is a schematic diagram of an AC/DC switching output unit in a power supply system according to the present invention. detailed description

In order to make the objects, the technical solutions and the advantages of the present invention more comprehensible, the present invention will be further described in detail below with reference to the accompanying drawings.

Referring to FIG. 1, the present invention provides a high-voltage DC power supply system, including a high-voltage DC power supply, a standby AC power supply, and an AC-DC switching output unit for outputting an interlocking switch between a high-voltage DC power supply and a standby AC power supply to a power device.

Referring to FIG. 5, the AC/DC switching unit includes a DC input terminal and an AC input terminal, the DC input terminal is connected to the output end of the high voltage DC power source, and the AC input terminal is connected to the output terminal of the standby AC power source; the output end of the AC/DC switching output unit has a belt The selection switch of the interlock function, the AC/DC switching output unit can output DC power to the switching power supply device through the switching device in the case of AC/DC dual input, and the AC power can be output through the switching device for the non-switching power supply device. At the same time, when the high-voltage DC power supply fails, the standby AC power can be output to the powered device through the switching device.

Referring to FIG. 2, the high voltage DC power supply includes an AC input unit, a rectifier module, and a battery pack. Among them: 1) AC input unit, including manual/automatic switching device (QA1, QA2) and AC monitoring unit for switching dual AC power input (mains and generator), input two AC power input and rectifier module The input terminal is connected; 2) the rectifier module is used to provide high-voltage DC power supply, and the output end of the rectifier module is divided into two parallel circuits, one is connected to the DC input end of the AC-DC switching output unit, and the other is connected to the battery pack; 3) The battery pack It is used to supply power to the powered device through the AC/DC switching output unit when the rectifier module is not working.

Referring to FIG. 3, the AC monitoring unit is used for measuring the electrical signals of the two input and the AC bus, and can also output the control signal of the input switching device according to the two input states. The AC monitoring unit includes a detection CPU, a display interface, and a detection circuit for measuring three-phase voltage, current, and frequency. The outputs of the respective detection circuits are connected to the input of the detection CPU. The measured voltage, current and frequency and other electrical signals can be displayed on the display interface, and sound and light alarm signals and control signals can be emitted at the same time. The AC monitoring unit further includes a lightning arrester FV1, a microcircuit breaker QFV1 for turning on and off the arrester, and microcircuit breakers QPR1 and QPR2 QPRN for switching the respective rectifier units.

Referring to Figure 4, the rectifier module is used to rectify the alternating current into direct current, and the output voltage is continuously adjustable from 204V to 292V. The rectifier module can also charge or discharge the battery; the rectifier module has a current sharing function and has a sleep function in cooperation with the monitoring system.

The rectifier module includes at least one rectifying unit, and each rectifying unit includes a main circuit, a control circuit, and an auxiliary power circuit.

As can be seen in Figure 2, the battery pack includes a battery management unit and at least one battery. As a backup power of the high-voltage DC power supply, the battery pack is directly connected to the battery pack connection end of the DC bus, and is used for continuously supplying power to the powered device when the rectifier module fails to work;

The battery management unit includes a processor, a voltage measuring circuit, and a temperature detecting circuit, and processes The input terminals are respectively connected to the output terminals of the voltage measuring circuit and the temperature detecting circuit, and the voltage and temperature of each group of batteries are collected in real time.

The standby AC power supply, as a backup power source for the high-voltage DC power supply system, outputs AC power to the powered device. The standby AC power source can be a mains or a UPS, and its output is connected to the input of the AC/DC switching unit.

The alternate AC power source also includes an AC monitoring unit for measuring the state of the alternate AC power input. The AC monitoring unit includes a detection CPU, an AC voltage measuring circuit and an AC current measuring circuit, and an output of the AC voltage measuring circuit and the AC current measuring circuit are connected to the detecting CPU input.

It can also be seen from FIG. 2 that in the embodiment, the power supply system further includes a monitoring system, and the monitoring system is respectively connected with the AC monitoring unit, the rectifier module, the battery management unit, the standby AC monitoring unit, and the power distribution detection unit, and reads All work data information and control commands of the high voltage DC power supply system are taken and transmitted.

Claims

Claim

1. A high-voltage DC power supply system, comprising: a high-voltage DC power supply, a standby AC power source, and an AC-DC switching output unit for switching the high-voltage DC power supply and the standby AC power supply to each other and outputting the power to the power-consuming equipment.

2. The high voltage direct current power supply system according to claim 1, wherein: the AC/DC switching unit comprises a DC input terminal and an AC input terminal, the DC input terminal is connected to the output end of the high voltage DC power source, and the AC input terminal is in standby communication. The power output is connected; the output of the AC/DC switching output unit has a selector switch with an interlock function.

3. The high voltage DC power supply system according to claim 1, wherein: the high voltage DC power supply comprises an AC input unit, a rectifier module, and a battery pack; wherein: 1) an AC input unit, configured to switch dual AC power sources The input manual/automatic switching device and the AC monitoring unit connect the two AC power inputs to the input end of the rectifier module; 2) the rectifier module is used to provide the high voltage DC power supply, and the output terminals of the rectifier module are separated into two parallel circuits. One is connected to the DC input terminal of the AC/DC switching output unit, and the other is connected to the battery pack; 3) The battery pack is used to supply power to the powered device through the AC/DC switching output unit when the rectifier module is not working.

4. The high voltage direct current power supply system according to claim 1, wherein: the alternating current monitoring unit comprises a detection CPU, a display interface, and a detection circuit for measuring three-phase voltage, current and frequency; The outputs are connected to the input of the detection CPU.

The high voltage direct current power supply system according to claim 1, wherein: the rectifying module comprises at least one rectifying unit, each rectifying unit comprises three parts: a main circuit, a control circuit and an auxiliary power circuit; the main circuit includes Thunder unit, EMC/EMI circuit, AC filter circuit, power conversion circuit, rectifier circuit, DC-DC converter circuit, DC filter output circuit; After three-phase AC input is passed through lightning protection unit and EMC/EMI circuit, AC filtering; After the power conversion circuit, the output is rectified; the output is output to the DC-DC conversion circuit, and finally the output DC power is required; the control circuit includes an input over-voltage protection unit, a current limiting protection circuit, an output over-voltage protection circuit, and a short-circuit protection circuit. Voltage stabilizing loop, sampling circuit, PFC unit, PMW control unit; wherein PMW control unit collects input overvoltage and undervoltage protection unit, current limiting protection circuit, and output The voltage protection circuit, the short circuit protection circuit, and the voltage stabilization loop signal are summed into the power conversion circuit; the voltage stabilization loop collects information from the sampling circuit; the sampling circuit, the short circuit protection circuit, the output overvoltage protection circuit, and the current limiting protection The circuit collects information from the DC filter output circuit in the main circuit; the corresponding information of the AC filter circuit in the main circuit is respectively sent to the input over-voltage protection unit and the PFC unit, and the information in the input under-voltage protection unit is also transmitted. Into the PFC unit; the auxiliary power circuit is to provide the necessary power for the control circuit.

6. The high voltage direct current power supply system according to claim 1, wherein: the battery pack comprises a battery management unit and at least one set of batteries; the battery management unit comprises a processor, a voltage measuring circuit and a temperature detecting circuit, and the processor input The terminals are respectively connected to the output ends of the voltage measuring circuit and the temperature detecting circuit.

7. The high voltage direct current power supply system according to claim 1, wherein: the standby alternating current power source further comprises an alternating current monitoring unit for measuring a standby alternating current power input state, wherein the alternating current monitoring unit comprises a detecting CPU, an alternating current voltage measuring circuit, and The AC current measuring circuit, the output of the AC voltage measuring circuit and the AC current measuring circuit are connected to the detection CPU input.

8. The high voltage direct current power supply system according to claim 1, wherein: the AC/DC switching output unit further comprises an AC circuit breaker that turns on and off an AC input, a DC circuit breaker that turns on and off the DC input, and a miniature that is turned on and off. The circuit breaker and the power distribution detecting unit for monitoring the working state of the AC-DC switching output unit, the miniature circuit breaker has a mechanical interlocking device; the power distribution detecting unit comprises a voltage measuring circuit, a current measuring circuit and an insulation detecting circuit.

9. The high voltage direct current power supply system according to claim 8, wherein: the measuring end of the voltage measuring circuit and the measuring end of the current measuring circuit are connected to an output end of the AC/DC switching output unit; the AC/DC switching output unit The output end is provided with a leakage current sensor, and the detecting end of the insulation detecting circuit is connected to the output end of the leakage current sensor in the output end of the AC/DC switching output unit; the insulation detecting circuit further comprises an insulation detecting processor, and the leakage current sensor is a The soft magnetic core, the input end of the insulation detection processor is connected to the output end of the leakage current sensor, and when the ground fault occurs at any one of the output ends of the AC/DC switching output unit, the generated insulation information is transmitted to the monitoring system in time.

10. The high voltage direct current power supply system according to claim 1, further comprising: a monitoring system, the monitoring system and the alternating current monitoring unit, the rectifier module, the battery management unit, and the standby The communication monitoring unit and the power distribution detection unit are connected by communication; the monitoring system includes a display module and a system operation management unit, and the output of the system operation management unit is connected to the input end of the display module.