CN110854983A - Voltage stabilizing device and method for stabilizing sudden change of direct current bus voltage based on super capacitor - Google Patents
Voltage stabilizing device and method for stabilizing sudden change of direct current bus voltage based on super capacitor Download PDFInfo
- Publication number
- CN110854983A CN110854983A CN201911206661.9A CN201911206661A CN110854983A CN 110854983 A CN110854983 A CN 110854983A CN 201911206661 A CN201911206661 A CN 201911206661A CN 110854983 A CN110854983 A CN 110854983A
- Authority
- CN
- China
- Prior art keywords
- voltage
- bus
- conversion circuit
- super capacitor
- storage battery
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/34—Parallel operation in networks using both storage and other dc sources, e.g. providing buffering
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J1/00—Circuit arrangements for dc mains or dc distribution networks
- H02J1/10—Parallel operation of dc sources
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/34—Parallel operation in networks using both storage and other dc sources, e.g. providing buffering
- H02J7/345—Parallel operation in networks using both storage and other dc sources, e.g. providing buffering using capacitors as storage or buffering devices
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
Abstract
The invention discloses a voltage stabilizing device and a method for stabilizing voltage mutation of a direct current bus based on a super capacitor, wherein the voltage stabilizing device comprises a detection circuit, a control circuit, a conversion circuit and a hybrid energy storage module, wherein the detection circuit is connected to the direct current bus through a voltage sensor and a current sensor; the control circuit comprises a central processing unit, and the central processing unit controls the on-off of a voltage compensation bus circuit and a capacitor charging circuit according to the detected voltage value on the direct current bus; the conversion circuit adopts a bidirectional DC/DC Buck-Boost circuit and is used for charging the hybrid energy storage module or enabling the hybrid energy storage module to compensate a direct-current power grid; the hybrid energy storage module comprises a super capacitor bank array and a storage battery pack array; the super capacitor group array is formed by connecting a plurality of unit super capacitors in series and parallel, and the storage battery group array is formed by connecting a plurality of unit storage batteries in series and parallel. The method and the system can improve the quality of the electric energy of the data center in the intelligent park and ensure the stability of the incoming line voltage of the data center.
Description
Technical Field
The invention belongs to the technical field of direct current power grids, and particularly relates to a voltage stabilizing device and method for stabilizing direct current bus voltage mutation based on a super capacitor.
Background
With the development of distributed power supplies, the direct-current microgrid is widely applied as a system for efficient utilization. The direct-current micro-grid generally comprises a plurality of power modules such as power supplies and constant-power loads, when a distributed power supply or a load is switched into the direct-current grid, the sudden change of bus voltage can be caused, and the output power has volatility and randomness due to the fact that distributed energy in the micro-grid is easily influenced by environmental factors, and the sudden change of voltage is caused. The voltage mutations specifically comprise two manifestations: first, voltage sag, and second, voltage overshoot.
The data center is one of typical loads of an intelligent park, and when sudden change of bus voltage occurs, great threat is caused to the safety of data center equipment. The system oscillation, overvoltage or undervoltage protection misoperation can be caused, the operation efficiency and the service life of equipment in the data center are reduced if the equipment is in a light state, the switching power supply which is used by the data center in a large amount is withdrawn from operation if the equipment is in a heavy state, and the equipment is burnt if the equipment is in a serious state.
In the prior art, the bus voltage fluctuation is only stabilized in an alternating current system, and along with the development of a direct current power distribution network, when the direct current power distribution network generates voltage mutation, bus voltage stabilizing equipment for the direct current power distribution network is needed, so that the stable operation of loads is ensured.
Disclosure of Invention
The invention aims to provide a voltage stabilizing device and a voltage stabilizing method for stabilizing sudden change of direct current bus voltage based on a super capacitor, so as to overcome the defects of the prior art.
In order to achieve the purpose, the invention adopts the following technical scheme:
a voltage stabilizing device for stabilizing sudden change of direct current bus voltage based on a super capacitor comprises a detection circuit, a control circuit, a conversion circuit and a hybrid energy storage module, wherein the detection circuit is connected to the direct current bus in parallel through a voltage sensor; the control circuit is used for controlling the on-off of the conversion circuit according to the detected voltage value on the direct current bus; the conversion circuit adopts a bidirectional DC/DC Buck-Boost circuit and is used for charging the hybrid energy storage module or enabling the hybrid energy storage module to compensate a direct-current power grid; the hybrid energy storage module comprises a super capacitor bank array and a storage battery pack array; the super capacitor bank array is formed by connecting n groups of super capacitors in parallel, n is an even number, the super capacitor bank is formed by connecting a plurality of unit super capacitors in series, the storage battery bank array is formed by connecting n groups of storage batteries in parallel, n is an even number, and the storage battery bank is formed by connecting m unit storage batteries in series.
A voltage stabilizing method for stabilizing sudden change of direct current bus voltage based on a super capacitor comprises the following steps:
step A: the detection circuit measures the voltage of the direct current bus through the voltage sensor, sends data to the control unit, calculates the voltage change rate and the voltage value, and compares the voltage value with a preset value;
and B: the control circuit judges the voltage change rate and the voltage value and determines how the hybrid energy storage participates in the operation of the conversion circuit;
and C: after the judgment of the step B, the control circuit starts to control the operation of the conversion circuit and determines how the conversion circuit works;
step D: setting rated voltage of DC bus to UNDetecting the bus voltage again, and judging whether the steady state voltage value is 0.995U or notNTo 1.005UNAnd if the voltage change rate is lower than the preset value, ending the stabilizing of the bus voltage, and if the voltage change rate is not lower than the preset value, repeating the steps A to D.
Further, in step a: when the detected voltage value exceeds the rated voltage and the voltage conversion rate reaches 0.2% per second, the voltage value is defined as voltage overshoot, and when the voltage value is lower than the rated voltage and the voltage change rate reaches 0.2% per second, the voltage value is defined as voltage drop; in addition, when the voltage value is 0.975UNTo 0.995UN，1.005UNTo 1.025UNDefined as region I when the voltage value is 1.005UNTo 1.05UNAnd 0.995UNTo 0.975UNDefined as zone II.
Further, step B specifically includes:
step B1: judging whether the voltage change rate reaches a preset value, if not, judging whether the steady-state voltage value changes, if so, when the voltage value is higher than UNAfter calculating the compensation voltage, the conversion circuit works in Buck mode, and at this time, whether the detected voltage value is in the I area or the II area is judged again, if so, the conversion circuit works in Buck modeThe group of storage battery packs work in a charging state, and if the group of storage battery packs work in the region II, the n groups of storage battery packs work in the charging state; when the voltage value is lower than UNAfter calculating the compensation voltage, the conversion circuit works in a Boost mode, at the moment, whether the detected voltage value is in a region I or a region II is judged again, and if the detected voltage value is in the region I, the conversion circuit works in the Boost modeThe group storage battery set works in a discharging state, if the group storage battery set works in the second zone, the n group storage battery sets work in a discharging stateState;
step B2: when the voltage change rate reaches a preset value and the steady-state voltage is 0.995UNTo 1.005UNIn the method, only the super capacitor bank array is controlled to stabilize the sudden change of the bus voltage when the voltage is higher than UNWhen the compensation voltage is calculated, the conversion circuit works in a Boost mode, and the super capacitor bank array works in a charging state; when the voltage is lower than UNWhen the compensation voltage is calculated, the conversion circuit works in a Buck mode, and the super capacitor bank array works in a discharge state;
step B3: when the voltage change rate reaches a preset value and the steady-state voltage changes in a region I or a region II, when the voltage is higher than UNAnd the steady state voltage is stabilized in the region I, and the compensation voltage is calculated and firstly controlled
The super capacitor group carries out bus voltage stabilization, the bus voltage is reduced to a stable state, and then the control is carried out
The group storage battery pack stabilizes the bus voltage; when the voltage is higher than UNAnd the steady state voltage is stabilized in the area II, through calculating the compensating voltage, control n groups of super capacitor groups to carry on the bus voltage to stabilize first, drop the bus voltage to the steady state, then control n groups of storage battery group to stabilize the bus voltage; when the voltage is lower than UNAnd the steady state voltage is stabilized in the region I, and the compensation voltage is calculated and firstly controlled
The super capacitor group carries out bus voltage stabilization, raises the bus voltage to a stable state, and then controls
The group storage battery pack stabilizes the bus voltage; when the voltage is lower than UNAnd the steady state voltage is stabilized in the area II, through calculating the compensation voltage, firstly controlling n groups of super capacitor groups to stabilize the bus voltage, raising the bus voltage to a stable state, and then controlling n groups of storage battery groups to stabilize the bus voltagePressing;
step B4: and if the voltage change rate and the steady-state voltage value are changed, ending the bus voltage stabilizing program.
Further, step C specifically includes:
step C1: after the judgment of the step B, the conversion circuit needs to work, a switch tube V1 and a switch tube V2 in the conversion circuit both adopt a full-control switch tube IGBT, the conversion circuit is structurally characterized in that the hybrid energy storage and a large inductor are connected in series and then connected in parallel to a switch tube V2, a switch tube V2 is connected in parallel with a diode in reverse, an emitter of the switch tube V1 is connected with a collector of a switch tube V2, a switch tube V1 is connected in parallel with a diode in reverse, the switch tube V1 and a switch tube V2 are connected in parallel with a large capacitor and then connected to a direct current bus, if the conversion circuit works in a Buck mode, the switch tube V1 is switched on, the switch tube V2 is completely switched off, and during the switching-on period of the switch tube V1, because the voltage on the direct current side is greater than the hybrid energy storage voltage, the energy; during the turn-off period of the switching tube V1, the electromagnetic energy stored in the inductor continues to charge the hybrid energy storage through the reverse parallel diode D2 of the switching tube V2, and the charging voltage of the hybrid energy storage is changed by controlling the switching duty cycle and the duty ratio of the switching tube V1;
step C2: through the judgment of the step B, if the conversion circuit works in the Boost mode, at this time, the switching tube V2 is turned on, the switching tube V1 is completely turned off, the switching period is set to be Ts, Ton is set to be D Ts during the on period of the switching tube V2, where D is the duty ratio and Ton is the on time, and the hybrid energy storage module stores energy in the inductor L through the switching tube V2; during the off period of the switching tube V2, Toff is (1-D) Ts, the electromagnetic energy stored in the inductor L is released to the dc side through the anti-parallel diode D1 of the switching tube V1, and the dc side voltage is adjusted by controlling the duty cycle and duty ratio of the switching tube V2.
Compared with the prior art, the invention has the following beneficial technical effects:
the super capacitor in the device for stabilizing the voltage mutation of the direct current bus based on the super capacitor has the advantages of high power density, long cycle life, high charging and discharging speed and high dynamic response, and can quickly stabilize the voltage mutation of the direct current bus; the storage battery has the characteristics of high energy density, low power density and the like, and can continuously and stably stabilize the voltage fluctuation of the direct-current bus. The energy storage device disclosed by the invention combines the super capacitor and the storage battery, when the voltage of the direct current bus suddenly changes or fluctuates independently, the energy storage device can quickly and efficiently stabilize, and when the voltage of the direct current bus suddenly changes and fluctuates simultaneously, the energy storage device can quickly stabilize the voltage of the direct current bus suddenly changes and fluctuates.
When the voltage of the direct current bus is overshot or dropped, the device can quickly compensate the voltage of the direct current bus, and the continuous and stable operation of a load is guaranteed. The matched equipment for stabilizing the voltage mutation is installed before the data center is fed with the line, and a certain control strategy is adopted, so that the voltage fluctuation can be effectively stabilized, the power supply quality of the micro-grid is improved, and the reliable operation of the data center is ensured.
In summary, the installation of the device by a data center user is the most feasible way for inhibiting voltage abrupt change.
Drawings
FIG. 1 is a schematic view of the installation location of the present invention;
FIG. 2 is a block diagram of the present invention;
FIG. 3 is a schematic diagram of an array of supercapacitors and batteries;
FIG. 4 is a schematic diagram of a bi-directional DC/DC converter circuit;
FIG. 5 is a converter control strategy control block diagram;
FIG. 6 is a flow chart for smoothing bus voltage transients;
FIG. 7 is a voltage partition.
Detailed Description
The invention is described in further detail below:
a voltage stabilizing device for stabilizing sudden change of direct current bus voltage based on a super capacitor comprises a detection circuit, a control circuit, a conversion circuit and a hybrid energy storage module, wherein the detection circuit is connected to the direct current bus in parallel through a voltage sensor; and the control circuit controls the on-off of the voltage compensation bus circuit and the capacitor charging circuit according to the detected voltage value on the direct current bus. The control circuit comprises a central processing unit and a peripheral circuit for assisting the central processing unit, wherein the central processing unit controls the on-off of the conversion circuit according to the detected voltage value on the direct current bus; the conversion circuit adopts a bidirectional DC-DC converter, so that the hybrid energy storage module can be charged and can be compensated for a direct-current power grid; the hybrid energy storage module comprises a super capacitor bank array and a storage battery array. The super capacitor bank array is composed of a plurality of unit super capacitors in a series-parallel connection mode, and the storage battery bank array is also composed of unit storage batteries in a series-parallel connection mode.
The voltage detection method comprises two voltage detection modes, namely, voltage change rate is detected, when the voltage exceeds rated voltage and the change rate reaches 0.2% per second, voltage overshoot is defined, and when the voltage is lower than the rated voltage and the voltage change rate reaches 0.2% per second, voltage drop is defined; secondly, detecting a steady state voltage value, and setting the rated voltage of the bus to be UNWhen the voltage value is 0.975UNTo 0.995UN，1.005UNTo 1.025UNDefined as region I when the voltage value is 1.005UNTo 1.05UNAnd 0.995UNTo 0.975UNDefined as zone II. The detection circuit adopts a voltage Hall sensor, sends a direct current bus voltage signal to the control unit in real time, preferentially calculates the voltage change rate, and then judges the steady-state voltage value. The voltage data is processed to calculate a compensation voltage value.
The conversion circuit adopts a bidirectional DC/DC Buck-Boost circuit, so that bidirectional flow of power can be realized, and charging and discharging of the hybrid energy storage can be realized. The hybrid energy storage and the large inductor are connected in series and then connected in parallel to a full-control switch tube V2, a switch tube V2 needs to be connected in anti-parallel with a diode, an emitter of a switch tube V1 is connected with a collector of a switch tube V2, the switch tube V1 needs to be connected in anti-parallel with a diode, and the switch tube V1 and the switch tube V2 are connected in parallel with the large capacitor and then connected to a direct current bus. The circuit is shown in figure 4. The control strategy adopts voltage droop control and voltage outer loop current inner loop control, and a voltage droop control loop is additionally arranged on the basis of a common voltage current loop, so that the control of the converter can be more accurate, and the control strategy is as shown in figure 5. When the acquired voltage value of the direct current bus is higher than the rated voltage value of the bus, the conversion circuit works in a Buck mode, energy flows from the direct current power grid to the energy storage module, so that the voltage fluctuation of the direct current bus is stabilized, the voltage of the direct current bus is reduced, the voltage of the direct current bus is maintained within a rated range, and the voltage of the incoming line of the data center does not generate large fluctuation; when the collected direct current bus voltage value is lower than the bus voltage rated value, the conversion circuit works in a Boost mode, and energy flows to a direct current power grid from the hybrid energy storage module, so that the direct current bus voltage fluctuation is stabilized and the direct current bus voltage is improved.
The hybrid energy storage module comprises a super capacitor bank array and a storage battery array, and the super capacitor has the characteristics of small energy density, high power density, long cycle life, high charging and discharging speed, high dynamic response and the like, and can quickly stabilize voltage mutation of a direct current bus when voltage overshoot and voltage drop occur; the storage battery has the characteristics of large energy density, small power density, short cycle life, low charging and discharging speed, low dynamic response and the like, and is suitable for stabilizing voltage fluctuation when the voltage value of the bus is stabilized in a region I and a region II. The super capacitor bank array is not a single capacitor, but a capacitor bank is formed by connecting unit capacitors in series and parallel. The super capacitor has three composition modes: series connection, parallel connection and series-parallel connection. The working voltage of a single capacitor is not high, and the requirement of actual working conditions cannot be met, so that the capacitors are required to be connected in series. However, the series connection of the capacitors also has a problem, and due to the inherent difference of the capacitors, a voltage imbalance problem exists in a circuit, and the capacitors are affected in severe cases, so that the overall performance is affected. The parallel capacitors can input and output large current, but the existence of the charging and discharging resistors causes a control circuit for adjusting the resistors to be extremely complex and difficult to control. The series-parallel super capacitor battery pack has the advantages of series connection and parallel connection, and the defects of two modes are avoided. The storage battery also has the problems caused by the series-parallel connection mode, so the super capacitor bank and the storage battery pack both adopt the series-parallel connection mode. In the hybrid energy storage module, a super capacitor bank array is formed by connecting n groups of super capacitors in parallel, n is an even number, the super capacitor bank is formed by connecting a plurality of unit super capacitors in series, a storage battery bank array is formed by connecting n groups of storage batteries in parallel, n is an even number, and the storage battery bank is formed by connecting m unit storage batteries in series.
The energy management strategy of hybrid energy storage is as follows: when only the bus voltage conversion rate changes, the compensation voltage is calculated by the control unit, and then only the super capacitor is charged and discharged, so that sudden change of the bus voltage can be quickly stabilized. When only the steady-state voltage exceeds the rated voltage, the storage battery is only charged and discharged after the control unit calculates the compensation voltage, because when the bus voltage is stabilized at a certain value, the power of the capacitor is not enough compensated, the advantage of large energy density of the storage battery is utilized, and the fluctuation of the bus voltage can be stably stabilized. When the bus voltage transformation rate changes and the steady state voltage exceeds the region II at the same time, the control unit calculates the compensation voltage, then the super capacitor bank stabilizes the bus voltage, the bus voltage is pulled back to the region II, and then the storage battery is used for compensating the bus voltage. Detecting whether the DC bus voltage reaches the rated range and 0.995U after compensationNTo 1.005UNIf the preset range is reached, compensation is not carried out, and if the preset range is not reached, compensation is continued.
The invention also provides a voltage stabilizing method for stabilizing the voltage mutation of the direct current bus based on the super capacitor, and the method has good dynamic response, can quickly stabilize the voltage mutation and maintain the voltage stability of the system. Due to the fact that the data center has high requirements for power quality, common power quality problems such as voltage drop and voltage overshoot affect normal operation of the data center. Therefore, the most feasible way is to install the stabilizing device at the front end of the service wire of the data center to inhibit the voltage sudden change.
How to smooth the sudden bus voltage change is further described with reference to fig. 6.
Step A: the detection circuit measures the voltage of the direct current bus through the voltage sensor, sends data to the control unit, calculates the voltage change rate and the voltage value, and compares the voltage value with a preset value. When the voltage exceeds the rated voltage and the transformation rate reaches 0.2% per second, the voltage overshoot is defined, and when the voltage is lower than the rated voltage and the voltage change rate reaches 0.2% per second, the voltage drop is defined; secondly, detecting a steady state voltage value when the voltage value is within0.975UNTo 0.995UN，1.005UNTo 1.025UNDefined as region I when the voltage value is 1.005UNTo 1.05UNAnd 0.995UNTo 0.975UNDefined as zone II. After being processed, the next step is carried out.
And B: the control circuit judges the voltage change rate and the voltage value and determines how the hybrid energy storage participates in the operation of the conversion circuit.
(B1) Judging whether the voltage change rate reaches a preset value, if not, judging whether the steady-state voltage value changes, if so, when the voltage value is higher than UNAfter the compensation voltage is calculated, the conversion circuit works in a Buck mode, at the moment, whether the detected voltage value is in a region I or a region II needs to be judged again, and if the detected voltage value is in the region I, the conversion circuit works in the Buck mode
The pack battery is operated in a charged state. If the battery pack is in the area II, enabling n groups of battery packs to work in a charging state; when the voltage value is lower than UNAfter calculating the compensation voltage, the conversion circuit is made to work in a Boost mode, and at this time, whether the detected voltage value is in the I area or the II area needs to be judged again, if so, the conversion circuit is made to work in the Boost mode
The pack battery is operated in a discharge state. If the battery is in the area II, enabling the n groups of storage batteries to work in a discharging state;
(B2) when the voltage change rate reaches a preset value and the steady-state voltage is 0.995UNTo 1.005UNIn, only control super capacitor group and carry out the sudden change of flat busbar voltage, because combine super capacitor's characteristics, can charge and discharge fast, can reach the effect of fine flat direct current busbar voltage sudden change. When the voltage is higher than UNWhen the compensation voltage is calculated, the conversion circuit works in a Boost mode, and the super capacitor bank works in a charging state; when the voltage is lower than UNDuring the process, after the compensation voltage is calculated, the conversion circuit works in a Buck mode, and the super capacitor bank works in a discharging state.
(B3) When the voltage change rate reaches a preset value and the steady-state voltage changes in a region I or a region II, when the voltage is higher than UNAnd the steady state voltage is stabilized in the region I, and the compensation voltage is calculated and firstly controlled
The super capacitor group carries out bus voltage stabilization, the bus voltage is reduced to a stable state, and then the control is carried out
The group storage battery pack stabilizes the bus voltage; when the voltage is higher than UNAnd the steady state voltage is stabilized in the area II, through calculating the compensating voltage, control n groups of super capacitor groups to carry on the bus voltage to stabilize first, drop the bus voltage to the steady state, then control n groups of storage battery group to stabilize the bus voltage; when the voltage is lower than UNAnd the steady state voltage is stabilized in the region I, and the compensation voltage is calculated and firstly controlled
The super capacitor group carries out bus voltage stabilization, raises the bus voltage to a stable state, and then controls
The group storage battery pack stabilizes the bus voltage; when the voltage is lower than UNAnd the steady state voltage is stabilized in the area II, through calculating the compensation voltage, firstly controlling n groups of super capacitor groups to stabilize the bus voltage, raising the bus voltage to a stable state, and then controlling n groups of storage battery groups to stabilize the bus voltage.
(B4) And if the voltage change rate and the steady-state voltage value are changed, ending the bus voltage stabilizing program.
And C: and B, after the judgment of the step B, the control circuit starts to control the operation of the conversion circuit and determines how the conversion circuit works.
(C1) Through the judgment of the step B, if the conversion circuit works in the Buck mode, the switching tube V1 is turned on, the switching tube V2 is completely turned off, and during the period that the switching tube V1 is turned on, because the voltage on the direct current side is greater than the hybrid energy storage voltage, the energy in the direct current network can be absorbed by the inductor and then the hybrid energy storage module is charged; during the turn-off period of the switching tube V1, the electromagnetic energy stored in the inductor continues to charge the hybrid energy storage through the reverse parallel diode D2 of the switching tube V2, and the charging voltage of the hybrid energy storage is changed by controlling the switching duty cycle and the duty ratio of the switching tube V1;
(C2) through the judgment of the step B, if the conversion circuit works in the Boost mode, at this time, the switching tube V2 is turned on, the switching tube V1 is completely turned off, the switching period is set to be Ts, Ton is set to be D Ts during the on period of the switching tube V2, where D is the duty ratio and Ton is the on time, and the hybrid energy storage module stores energy in the inductor L through the switching tube V2; during the off period of the switching tube V2, Toff is (1-D) Ts, the electromagnetic energy stored in the inductor L is released to the dc side through the anti-parallel diode D1 of the switching tube V1, and the dc side voltage is adjusted by controlling the duty cycle and duty ratio of the switching tube V2.
Step D: setting rated voltage of DC bus to UNDetecting the bus voltage again, and judging whether the steady state voltage value is 0.995U or notNTo 1.005UNAnd if the voltage change rate is lower than the preset value, ending the stabilizing of the bus voltage, and if the voltage change rate is not lower than the preset value, repeating the steps A to D.
When the voltage of the direct current bus is suddenly changed, the system generates a proper compensation voltage to be injected into the direct current network system, so that the voltage of the data center is stable, and the protected equipment is not influenced by the voltage change until the voltage of the direct current bus is recovered to be normal. The system is in a standby state when the voltage of the direct current bus is normal, the energy storage is charged when voltage overshoot occurs, and the energy storage is discharged when voltage drop occurs.
Claims (5)
1. A voltage stabilizing device for stabilizing sudden change of direct current bus voltage based on a super capacitor is characterized by comprising a detection circuit, a control circuit, a conversion circuit and a hybrid energy storage module, wherein the detection circuit is connected to the direct current bus in parallel through a voltage sensor; the control circuit is used for controlling the on-off of the conversion circuit according to the detected voltage value on the direct current bus; the conversion circuit adopts a bidirectional DC/DC Buck-Boost circuit and is used for charging the hybrid energy storage module or enabling the hybrid energy storage module to compensate a direct-current power grid; the hybrid energy storage module comprises a super capacitor bank array and a storage battery pack array; the super capacitor bank array is formed by connecting n groups of super capacitors in parallel, n is an even number, the super capacitor bank is formed by connecting a plurality of unit super capacitors in series, the storage battery bank array is formed by connecting n groups of storage batteries in parallel, n is an even number, and the storage battery bank is formed by connecting m unit storage batteries in series.
2. A voltage stabilizing method based on super-capacitor stabilizing direct-current bus voltage sudden change adopts the voltage stabilizing device based on super-capacitor stabilizing direct-current bus voltage sudden change, which is characterized by comprising the following steps:
step A: the detection circuit measures the voltage of the direct current bus through the voltage sensor, sends data to the control unit, calculates the voltage change rate and the voltage value, and compares the voltage value with a preset value;
and B: the control circuit judges the voltage change rate and the voltage value and determines how the hybrid energy storage participates in the operation of the conversion circuit;
and C: after the judgment of the step B, the control circuit starts to control the operation of the conversion circuit and determines how the conversion circuit works;
step D: setting rated voltage of DC bus to UNDetecting the bus voltage again, and judging whether the steady state voltage value is 0.995U or notNTo 1.005UNAnd if the voltage change rate is lower than the preset value, ending the stabilizing of the bus voltage, and if the voltage change rate is not lower than the preset value, repeating the steps A to D.
3. The voltage stabilizing method based on super-capacitor suppression of sudden change of direct-current bus voltage according to claim 2, characterized in that in step A: when the detected voltage value exceeds the rated voltage and the voltage conversion rate reaches 0.2% per second, the voltage overshoot is defined, and when the voltage value is lower than the rated voltage and the voltage change rate reaches 0.2% per second, the voltage drop is definedDropping; in addition, when the voltage value is 0.975UNTo 0.995UN，1.005UNTo 1.025UNDefined as region I when the voltage value is 1.005UNTo 1.05UNAnd 0.995UNTo 0.975UNDefined as zone II.
4. The voltage stabilizing method based on super-capacitor suppression direct-current bus voltage sudden change according to claim 3, wherein the step B specifically comprises:
step B1: judging whether the voltage change rate reaches a preset value, if not, judging whether the steady-state voltage value changes, if so, when the voltage value is higher than UNAfter calculating the compensation voltage, the conversion circuit works in Buck mode, and at this time, whether the detected voltage value is in the I area or the II area is judged again, if so, the conversion circuit works in Buck mode
The group of storage battery packs work in a charging state, and if the group of storage battery packs work in the region II, the n groups of storage battery packs work in the charging state; when the voltage value is lower than UNAfter calculating the compensation voltage, the conversion circuit works in a Boost mode, at the moment, whether the detected voltage value is in a region I or a region II is judged again, and if the detected voltage value is in the region I, the conversion circuit works in the Boost mode
The group of storage battery packs work in a discharging state, if the group of storage battery packs work in the area II, the n groups of storage battery packs work in the discharging state;
step B2: when the voltage change rate reaches a preset value and the steady-state voltage is 0.995UNTo 1.005UNIn the method, only the super capacitor bank array is controlled to stabilize the sudden change of the bus voltage when the voltage is higher than UNWhen the compensation voltage is calculated, the conversion circuit works in a Boost mode, and the super capacitor bank array works in a charging state; when the voltage is lower than UNWhen the compensation voltage is calculated, the conversion circuit works in a Buck mode, and the super capacitor bank array works in a discharge state;
step B3: when the voltage change rate reaches a preset value and the steady-state voltage changes in a region I or a region II, when the voltage is higher than UNAnd the steady state voltage is stabilized in the region I, and the compensation voltage is calculated and firstly controlled
The super capacitor group carries out bus voltage stabilization, the bus voltage is reduced to a stable state, and then the control is carried out
The group storage battery pack stabilizes the bus voltage; when the voltage is higher than UNAnd the steady state voltage is stabilized in the area II, through calculating the compensating voltage, control n groups of super capacitor groups to carry on the bus voltage to stabilize first, drop the bus voltage to the steady state, then control n groups of storage battery group to stabilize the bus voltage; when the voltage is lower than UNAnd the steady state voltage is stabilized in the region I, and the compensation voltage is calculated and firstly controlled
The super capacitor group carries out bus voltage stabilization, raises the bus voltage to a stable state, and then controlsThe group storage battery pack stabilizes the bus voltage; when the voltage is lower than UNAnd the steady state voltage is stabilized in the area II, through calculating the compensating voltage, control n groups of super capacitor groups to carry on the bus voltage to stabilize first, raise the bus voltage to the steady state, control n groups of storage battery group to stabilize the bus voltage;
step B4: and if the voltage change rate and the steady-state voltage value are changed, ending the bus voltage stabilizing program.
5. The voltage stabilization method based on super-capacitor suppression of sudden change of direct-current bus voltage according to claim 3, wherein the step C specifically comprises:
step C1: after the judgment of the step B, the conversion circuit needs to work, a switch tube V1 and a switch tube V2 in the conversion circuit both adopt a full-control switch tube IGBT, the conversion circuit is structurally characterized in that the hybrid energy storage and a large inductor are connected in series and then connected in parallel to a switch tube V2, a switch tube V2 is connected in parallel with a diode in reverse, an emitter of the switch tube V1 is connected with a collector of a switch tube V2, a switch tube V1 is connected in parallel with a diode in reverse, the switch tube V1 and a switch tube V2 are connected in parallel with a large capacitor and then connected to a direct current bus, if the conversion circuit works in a Buck mode, the switch tube V1 is switched on, the switch tube V2 is completely switched off, and during the switching-on period of the switch tube V1, because the voltage on the direct current side is greater than the hybrid energy storage voltage, the energy; during the turn-off period of the switching tube V1, the electromagnetic energy stored in the inductor continues to charge the hybrid energy storage through the reverse parallel diode D2 of the switching tube V2, and the charging voltage of the hybrid energy storage is changed by controlling the switching duty cycle and the duty ratio of the switching tube V1;
step C2: through the judgment of the step B, if the conversion circuit works in the Boost mode, at this time, the switching tube V2 is turned on, the switching tube V1 is completely turned off, the switching period is set to be Ts, Ton is set to be D Ts during the on period of the switching tube V2, where D is the duty ratio and Ton is the on time, and the hybrid energy storage module stores energy in the inductor L through the switching tube V2; during the off period of the switching tube V2, Toff is (1-D) Ts, the electromagnetic energy stored in the inductor L is released to the dc side through the anti-parallel diode D1 of the switching tube V1, and the dc side voltage is adjusted by controlling the duty cycle and duty ratio of the switching tube V2.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911206661.9A CN110854983B (en) | 2019-11-29 | 2019-11-29 | Voltage stabilizing device and method for stabilizing sudden change of direct current bus voltage based on super capacitor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911206661.9A CN110854983B (en) | 2019-11-29 | 2019-11-29 | Voltage stabilizing device and method for stabilizing sudden change of direct current bus voltage based on super capacitor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110854983A true CN110854983A (en) | 2020-02-28 |
| CN110854983B CN110854983B (en) | 2021-05-25 |
Family
ID=69606698
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911206661.9A Active CN110854983B (en) | 2019-11-29 | 2019-11-29 | Voltage stabilizing device and method for stabilizing sudden change of direct current bus voltage based on super capacitor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110854983B (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111431253A (en) * | 2020-05-08 | 2020-07-17 | 江苏云邦电子科技有限公司 | Overvoltage protection system and method for energy storage power supply, electronic device and storage medium |
| CN112421135A (en) * | 2020-11-20 | 2021-02-26 | 四川长虹电器股份有限公司 | Series energy storage battery direct current conversion system and control method thereof |
| CN112671007A (en) * | 2020-12-28 | 2021-04-16 | 浙江朗普电气科技有限公司 | Frequency conversion anti-disturbance intelligent regulation device |
| CN113285518A (en) * | 2021-04-12 | 2021-08-20 | 中广核研究院有限公司 | DC power supply system |
| CN113328450A (en) * | 2020-12-28 | 2021-08-31 | 青岛鼎信通讯股份有限公司 | Start-stop bus compensation method for tail end low voltage treatment device |
| WO2022012427A1 (en) * | 2020-07-14 | 2022-01-20 | 珠海格力电器股份有限公司 | Direct-current power supply and distribution control method and system and direct-current micro data center |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102185329A (en) * | 2011-05-04 | 2011-09-14 | 华北电力大学 | Super-capacitor-based DC voltage sag suppression device and suppression method thereof |
| CN104218658A (en) * | 2014-09-18 | 2014-12-17 | 上海电力学院 | Control method for micro-grid hybrid energy storage system |
| CN105429128A (en) * | 2016-01-08 | 2016-03-23 | 江苏省电力公司电力科学研究院 | DC micro grid bus voltage control strategy based on hybrid energy storage |
| US20160118799A1 (en) * | 2014-10-22 | 2016-04-28 | SEWW Energy Inc. | Apparatuses, Methods, and Systems for Sustainable Energy Microgrid Mobile Medical Solutions |
| CN110445120A (en) * | 2019-08-06 | 2019-11-12 | 太原科技大学 | Direct-current grid busbar voltage control strategy based on hybrid energy-storing |
-
2019
- 2019-11-29 CN CN201911206661.9A patent/CN110854983B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102185329A (en) * | 2011-05-04 | 2011-09-14 | 华北电力大学 | Super-capacitor-based DC voltage sag suppression device and suppression method thereof |
| CN104218658A (en) * | 2014-09-18 | 2014-12-17 | 上海电力学院 | Control method for micro-grid hybrid energy storage system |
| US20160118799A1 (en) * | 2014-10-22 | 2016-04-28 | SEWW Energy Inc. | Apparatuses, Methods, and Systems for Sustainable Energy Microgrid Mobile Medical Solutions |
| CN105429128A (en) * | 2016-01-08 | 2016-03-23 | 江苏省电力公司电力科学研究院 | DC micro grid bus voltage control strategy based on hybrid energy storage |
| CN110445120A (en) * | 2019-08-06 | 2019-11-12 | 太原科技大学 | Direct-current grid busbar voltage control strategy based on hybrid energy-storing |
Non-Patent Citations (3)
| Title |
|---|
| XINBO LIU等: "Control Strategy of Super Capacitor-Battery Hybrid Energy Storage System Considering Constant Power Loads Characteristics", 《2018 21ST INTERNATIONAL CONFERENCE ON ELECTRICAL MACHINES AND SYSTEMS (ICEMS)》 * |
| 常晓勇等: "基于超级电容的直流微电网电压波动抑制研究", 《电力电子技术》 * |
| 王海波等: "平抑光伏系统波动的混合储能控制策略", 《电网技术》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111431253A (en) * | 2020-05-08 | 2020-07-17 | 江苏云邦电子科技有限公司 | Overvoltage protection system and method for energy storage power supply, electronic device and storage medium |
| WO2022012427A1 (en) * | 2020-07-14 | 2022-01-20 | 珠海格力电器股份有限公司 | Direct-current power supply and distribution control method and system and direct-current micro data center |
| CN112421135A (en) * | 2020-11-20 | 2021-02-26 | 四川长虹电器股份有限公司 | Series energy storage battery direct current conversion system and control method thereof |
| CN112671007A (en) * | 2020-12-28 | 2021-04-16 | 浙江朗普电气科技有限公司 | Frequency conversion anti-disturbance intelligent regulation device |
| CN113328450A (en) * | 2020-12-28 | 2021-08-31 | 青岛鼎信通讯股份有限公司 | Start-stop bus compensation method for tail end low voltage treatment device |
| CN113285518A (en) * | 2021-04-12 | 2021-08-20 | 中广核研究院有限公司 | DC power supply system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110854983B (en) | 2021-05-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110854983B (en) | Voltage stabilizing device and method for stabilizing sudden change of direct current bus voltage based on super capacitor | |
| CN106786490A (en) | Distributed DC microgrid energy control method | |
| CN113690873A (en) | Photovoltaic direct-current micro-grid coordination control method containing hybrid energy storage | |
| US10790769B2 (en) | Control method and control system for enhancing endurance to anomalous voltage for doubly-fed induction generator | |
| WO2017148251A1 (en) | Control system for enhancing frequency support of wind turbine generator | |
| US20040207366A1 (en) | Multi-mode renewable power converter system | |
| CN102088190A (en) | Grid-connected power storage system and method for controlling grid-connected power storage system | |
| CN101673963A (en) | Wind and solar hybrid generation system for communication base station based on dual direct-current bus control | |
| CN110120679B (en) | Household photovoltaic energy storage converter coupled with direct current side of photovoltaic inverter | |
| CN108054826B (en) | Light storage system for protecting anti-impact current storage battery | |
| CN109888845B (en) | AC/DC hybrid micro-grid | |
| CN105576685A (en) | Energy storage system for new energy micro-grid | |
| JP4566658B2 (en) | Power supply | |
| CN116054237A (en) | Power limiting method based on optical storage common direct current bus system | |
| CN108879783B (en) | Power spring energy consumption system | |
| CN112104306B (en) | Mixed type flexible loop closing device and optical storage sharing interface control method | |
| CN106026174B (en) | A kind of grid-connected photovoltaic system with intelligent power dividing function | |
| CN108667114A (en) | The control method of power supply system and power supply system | |
| CN218415866U (en) | Charging voltage and power automatic regulating system of energy storage system | |
| CN205724935U (en) | A kind of grid-connected photovoltaic system with intelligent power dividing function | |
| CN215322084U (en) | Energy storage type direct current charging pile | |
| JP4337687B2 (en) | Power supply | |
| JP4569223B2 (en) | Power supply | |
| CN113890156A (en) | Cable monitoring equipment power supply system combining multiple energy taking modes | |
| CN113852061A (en) | Photovoltaic power generation-containing DC micro-grid work control method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |