CN-121984209-A - AC/DC reserve integrated power supply system
Abstract
The invention discloses an AC/DC reserve integrated power supply system, which adopts mains supply as input and provides power for AC load and DC load, comprising: the alternating current-direct current (AC-DC) bidirectional converter, the AC-DC bidirectional converter, the battery pack, the switch and the control system are arranged, one end of the AC-DC bidirectional converter is connected with the AC bus, the other end of the AC-DC bidirectional converter is connected with the battery pack, one end of the DC-DC converter is connected with the battery pack, the other end of the DC-DC converter is connected with the direct current uninterruptible load, and the control system is used for controlling the battery pack to perform peak-shifting charge and discharge according to the monitored state of the mains supply. The invention realizes the uninterrupted power supply of important load and the continuous power supply of full load through the integral design of AC/DC reserve, realizes the seamless switching of normal DC direct-connected DC uninterrupted load, realizes the peak shifting charge and discharge and peak valley arbitrage by depending on an energy scheduling algorithm, and has obvious cost saving and long-term economic benefit obtaining.
Inventors
- XIAO MUXUAN
- YU GUOQIANG
Assignees
- 湖南时铭电气有限公司
Dates
- Publication Date
- 20260505
- Application Date
- 20260408
Claims (7)
- 1. The alternating current-direct current storage integrated power supply system is characterized by adopting commercial power as input and providing power for alternating current loads and direct current loads, and comprises an alternating current bus, an alternating current-direct current (AC-DC) bidirectional converter, a DC-DC converter, a battery pack, a wire inlet switch and a control system, wherein the alternating current bus is connected with the commercial power through the wire inlet switch and is connected with the alternating current loads and the direct current loads connected through a switching power supply, one end of the AC-DC bidirectional converter is connected with the alternating current bus, the other end of the AC-DC bidirectional converter is connected with the battery pack, one end of the DC-DC converter is connected with the battery pack, the other end of the DC-DC converter is connected with the direct current uninterruptible loads, and the control system is used for controlling the working states of the wire inlet switch, the AC-DC bidirectional converter, the DC-DC converter and the battery pack according to the monitored state of the commercial power; When the control system monitors that the commercial power is in a normal working range, the power grid is in a valley electricity price section, and the SOC of the battery pack is lower than a threshold value a, the commercial power is controlled to supply power for an alternating current load and a direct current load, and the battery pack is charged through an AC-DC converter; when the control system monitors that the commercial power is in a normal working range, and meanwhile, the power grid is in a peak-time power price section and the SOC of the battery pack is higher than a threshold value b, the battery pack is controlled to supply power to the alternating current load and supply direct current to the direct current load through an AC-DC bidirectional converter and a DC-DC converter respectively; When the control system monitors that the commercial power is in a normal working range and the power grid is in a valley electricity price section and the battery pack SOC is larger than a threshold value a, or the power grid is in a peak electricity price and the battery pack SOC is smaller than a threshold value b, the commercial power is controlled to supply power for an alternating current load and a direct current load, and the battery pack is not charged or discharged; When the control system monitors that the commercial power is lost or is not in a normal working range, and the SOC of the battery pack is higher than a threshold value c, the battery pack is controlled to provide direct current for the direct current load through the DC-DC converter, meanwhile, the control system turns off the incoming line switch, and the battery pack is controlled to supply power to the alternating current load through the AC-DC bidirectional converter; the relation of a, b and c is that a is larger than or equal to b is larger than or equal to c.
- 2. The alternating current-direct current storage integrated power supply system is characterized by adopting commercial power as input and providing power for alternating current loads and direct current loads, and comprises an alternating current bus, an alternating current-direct current (AC-DC) bidirectional converter, a DC-DC converter, a battery pack, a wire inlet switch and a control system, wherein the alternating current bus is connected with the commercial power through the wire inlet switch and is connected with the alternating current loads, one end of the AC-DC bidirectional converter is connected with the alternating current bus, the other end of the AC-DC bidirectional converter is connected with the battery pack, one end of the DC-DC converter is connected with the battery pack, the other end of the DC-DC converter is connected with the direct current loads, and the control system is used for controlling the working states of the wire inlet switch, the AC-DC bidirectional converter, the DC-DC converter and the battery pack according to the monitored state of the commercial power; when the control system monitors that the commercial power is in a normal working range, the power grid is at a valley electricity price section and the battery pack SOC is lower than a threshold value a, the commercial power is controlled to supply power to an alternating current load, the DC-DC converter supplies power to a direct current load, and the battery pack is charged through the AC-DC converter; When the control system monitors that the commercial power is in a normal working range and the power grid is at a peak time electricity price section and the SOC of the battery pack is higher than a threshold value b, the battery pack is controlled to supply power to the alternating current load and supply direct current to the direct current load through the AC-DC bidirectional converter and the DC-DC converter respectively; When the control system monitors that the commercial power is in a normal working range and the battery pack SOC of the electricity price section of the power grid at valley is larger than a threshold value a or the battery pack SOC at peak is smaller than a threshold value b, the commercial power is controlled to be an alternating current load, the DC-DC converter acquires energy from the AC-DC converter to supply power to the direct current load, and the battery pack is not charged or discharged; When the control system monitors that the commercial power is lost or is not in a normal working range, and the SOC of the battery pack is higher than a threshold value c, the battery pack is controlled to provide direct current for the direct current load through the DC-DC converter, meanwhile, the control system turns off the incoming line switch, and the battery pack is controlled to supply power to the alternating current load through the AC-DC bidirectional converter; the relation of a, b and c is that a is larger than or equal to b is larger than or equal to c.
- 3. The power supply system according to claim 1 or 2, wherein the battery pack is formed by connecting a plurality of battery packs in series, the DC-DC converter is formed by a plurality of DC-DC conversion sub-modules, and one end of each DC-DC conversion sub-module is connected to one or a plurality of battery packs connected in series, and the other end is connected to a direct current load.
- 4. The power supply system according to claim 1 or 2, wherein the number of ac loads and dc loads is plural.
- 5. The power supply system according to claim 1 or 2, wherein the mains is a three-phase 380V ac.
- 6. A power supply system according to claim 1 or 2, characterized in that the direct-current non-interruptible load voltage level is DC48V.
- 7. The power supply system according to claim 1 or 2, wherein the threshold a is equal to or less than a maximum value allowed by the battery pack SOC, the threshold c is equal to or more than a minimum value allowed by the battery pack SOC, and the threshold b is dependent on a difference between b and c, the power of the power supply load, and a time required for the dc uninterruptible load to be charged.
Description
AC/DC reserve integrated power supply system Technical Field The invention relates to the technical field of power supply systems, in particular to an alternating current and direct current storage integrated power supply system. Background In the key technical fields of industrial control, communication transmission, power operation and maintenance and the like, a large number of electric equipment loads with extremely high requirements on power supply continuity exist, the core requirements are that the power interruption time is strictly controlled within 10ms, and part of equipment adopts a direct-current voltage power supply mode, such as a server in a communication base station, a core communication module, a control protection system, an automatic operation system and the like of a transformer substation. Once the power supply of the power grid is interrupted, the equipment directly causes data loss, system shutdown and even key service paralysis, and serious economic loss or safety risk is caused, so that a reliable uninterrupted power supply guarantee scheme is needed. Aiming at the direct-current voltage electric equipment (the common voltage class is DC24V, DC V and other customized direct-current voltages), the existing main stream guarantee scheme is to connect a lead-acid storage battery pack in a power supply loop of the equipment, and provide short-time uninterrupted power supply for the equipment when the power grid is powered off through the electric energy stored by the lead-acid storage battery so as to avoid the power failure risk. However, the scheme has the obvious technical defects that firstly, the lead-acid storage battery is low in energy density, so that the lead-acid storage battery is huge in size and heavy in weight, high requirements are put into an installation space, secondly, the purchase cost and the later maintenance cost of the lead-acid storage battery are high, capacity detection and charge and discharge maintenance are required to be carried out regularly, the initial construction cost of a user is increased, additional manpower and material resources are required to be input for maintenance, the process is complex, thirdly, the actual utilization rate of the lead-acid storage battery is low, and the lead-acid storage battery is in an idle standby state in most cases and is put into use only when a power grid is powered off, so that the waste of resources is caused. Besides the above-mentioned direct current electric equipment, there are a large number of three-phase AC380V (including single-phase AC 220V) alternating current loads in industrial production and daily life, and such loads still need to maintain normal operation after the mains supply loses power, for example, key equipment of industrial production lines, refrigeration systems of data centers, and the like. At present, a diesel generator set is generally adopted as a standby power supply aiming at the standby power supply scheme of the alternating current load, namely, after mains supply is lost, the diesel generator set is started and put into power generation to provide continuous power supply for the alternating current load. The scheme has the same problems that firstly, the acquisition cost, the fuel consumption cost and the later maintenance cost of the diesel generator set are high, a heavy economic burden is brought to users after long-term use, secondly, the diesel generator set needs to be periodically subjected to maintenance operations such as start-up test operation, engine oil replacement, filter element cleaning and the like, or the diesel generator set is easy to start up failure to influence the power supply reliability, thirdly, the equipment utilization rate of the diesel generator set is low, the equipment is in an idle state and occupies a large storage space in most of time, and finally, larger noise and waste gas emission are generated when the diesel generator set operates, so that the diesel generator set not only pollutes the environment, but also can influence the work and life of surrounding personnel, and is especially not suitable for scenes with high requirements on noise and environmental protection. In order to solve the defects of the scheme, another standby power supply thought is provided in the industry, namely, a battery and an energy storage converter (PCS) are arranged at the electric equipment end, and the rapid switching and the integration after the mains supply is lost are realized through a static change-over switch (STS, STATIC TRANSFER SWITCH) so as to meet the requirement of power supply continuity. However, the power failure switching process involves three main processes of power grid power failure detection, STS static switch switching from on to off, and PCS switching from grid connection to off, each process requires a certain execution time, and has a severe requirement on cooperative control between STS and PCS, so that stable and reliable power sup