CN104134997A - Unified power quality controller employing resonant electronic switch, and method - Google Patents

Abstract

The invention relates to a unified power quality control device employing a resonant electronic switch, and belongs to the technical field of power electronics and flexible alternating current transmission and distribution. The device comprises the resonant electronic switch, a voltage source converter, an energy storage unit and a master control system, wherein the master control system consists of a master controller and a plurality of sensors; the resonant electronic switch comprises a group of inductors Lr1 and Lr2, a group of capacitors Cr1 and Cr2 and a group of bidirectional thyristors T1; a branch formed by connecting the bidirectional thyristors T1 in series with the inductor Lr2 and the capacitor Cr1 is connected in parallel with the inductor Lr1; and a parallel branch formed by Lr1, Lr2, Cr1 and T1 is connected in series with the capacitor Cr2. A method comprises the steps of judging various power quality faults and controlling the device to quickly switch and operate among four modes. The device has the advantages of simple structure, low cost, high overload resistance and high operation efficiency.

Description

Utilize Unified Power Quality Controller and the method thereof of mode of resonance electronic switch

Technical field

The invention belongs to power electronics and flexible AC power transmission and distribution technical field.Be particularly related to a kind of for joining, the power quality controlling device of using electricity system, especially relate to the Power Electronic Circuit device of mode of resonance electronic switch and energy-storage units energy-storage units and the operation method of this Power Electronic Circuit.

Background technology

The factor that affects quality of power supply situation is very complicated, and system is referred to as electrical energy power quality disturbance or power quality problem conventionally.According to the length of disturbance duration, can be divided into two large classes: what the duration was no more than some seconds levels is classified as discrete type disturbance conventionally, and for example voltage falls, voltage swells, voltage oscillation and transient overvoltage etc.; More long duration is continuous type disturbance, imbalance of three-phase voltage for example, voltage flicker, voltage harmonic and current harmonics etc.At modern petrochemical industry, electric power, electronics, communication, semiconductor manufacture, aviation, industrial robot and medicine equipment, and the field such as intelligent distribution network, micro-electrical network, owing to having used in a large number, the power supply quality of power supply is required to higher power electronic equipment or sensitive equipment, comprise high frequency electric source, frequency converter, chip manufacturing production line, data or computer center etc., be easy to be subject to the impact of all kinds of electrical energy power quality disturbances, especially to voltage fall with rise sharply, dynamic reactive, harmonic wave, voltage fluctuation and flicker and imbalance of three-phase voltage etc. are the most responsive.They not only affect the operational efficiency of sensitive equipment, reduce its useful life, seriously tend to cause misoperation or the damage of these equipment, cause the security incident that serious economic loss is even great.In addition, along with the continuous expansion of electric power system scale and the continuous increase of load capacity, between area power grid, internetwork-ing is increasingly tight in addition, and the use of Low ESR high-power transformer has all caused the rapid growth of power system short circuit capacity.When near region short circuit occurs for some high-rating generators and main transformer, short circuit current can reach 100～200kA.And initiatively the concept of power distribution network and micro-electrical network can not only cause the further growth of capacity of short circuit by the access power distribution network of a large amount of new forms of energy and distributed power source, also there is the problem of the short circuit tide turns that is difficult to expection.Proposed more strict requirement so just to various electric equipments (as circuit breaker, transformer and ground network etc.) in power system security, stable operation and electric power system, need properly settle fault current and suppress problem.

Rely on traditional power supply technique and be conventionally difficult to solve polytype Power Disturbance problem, this just need to adopt flexible AC distribution (Distributed Flexible AC Transmission System, D-FACTS) technology effectively to control various power quality problems.Nowadays D-FACTS equipment has become and has improved the quality of power supply, especially solves the powerful of Dynamic Power Quality Disturbances problem.Yet the D-FACTS equipment of the overwhelming majority adopts simple parallel connection type or tandem type to connect and control mode conventionally at present, only can solve part power quality problem.

As tandem type D-FACTS equipment, mainly by regulating series voltage to solve, join, the power quality problem of voltage aspect in using electricity system, exemplary apparatus comprises solid converting switch (Solid-State Transfer Switch, SSTS), dynamic voltage compensator (Dynamic Voltage Restorer, DVR), series connection type active electric power filter (Active Power Filter, APF) etc.The defect that wherein tandem type DVR device exists is: be only applicable to the system side voltage that fault forms that is short-circuited and fall, for no matter being the power failure of near-end circuit breaker trip generation or the short term outage of higher level's circuit breaker trip and back brake formation, DVR device all cannot form effective compensation circuit.Secondly, DVR device voltage fall or the condition that jumps under conventionally in electronics bypass condition, integral device utilance is very low, although can increase the compensate function to harmonic voltage as tandem type APF device, but it cannot suppress harmonic wave and reactive current, and the latter is main harmonic pollution source in actual distribution, using electricity system.The problem of solid converting switch technology SSTS is, first needs the support of the independent electric power supply of stand-by heat each other, and this is difficult to realize in many areas and application scenario, of a high price; Secondly, the SSTS realizing based on thyristor, controls because needs turn-off, and still has the power-off time of half cycle to cycle, for many sensitive loads, is unacceptable.

Parallel connection type D-FACTS equipment is connected in parallel in electrical network conventionally, can be by regulating its offset current that injects electrical network to solve the power quality problem that the trends such as harmonic wave and dynamic reactive electric current cause, or can be used as independently voltage source for load power supply is to solve the part quality of voltage problem in distribution system.Typical case's parallel connection type D-FACTS equipment comprises Distribution Static Compensator (Distributed Static Synchronous Compensator, D-STATCOM), parallel connection type active electric filter (Active Power Filter, APF) and Line interaction UPS (Line-Interactive Uninterruptible Powe rSupply) etc.Because D-STATCOM and parallel connection type APF equipment are to distribute and realize the inhibition to power quality problems such as voltage fluctuation, voltage flicker, harmonic waves by changing in distribution system trend, belong to indirect control mode, for voltage fall, the quality of voltage problem such as voltage swells cannot effectively control.Line interaction UPS can by with join, using electricity system disconnects fast and then independently solves voltage-type electrical energy power quality disturbance problem for load power supply, but there is larger defect joining, in using electricity system this key issue of quick-disconnect time in it, currently used alternating electron by-pass switch is longer opening time, typical case's time is 4～10ms, cause the output of UPS to have the power failure of certain hour, for responsive type load, remain unacceptable.

Comprehensive D-FACTS equipment grows up just in this case.Comprehensive D-FACTS equipment can solve simultaneously join, voltage and current two class power quality problems in using electricity system, exemplary apparatus comprises Unified Power Quality Controller (Unified Power Quality Controller, UPQC), two changing type UPS (Double Conversion UPS) and online interaction formula delta type UPS (Line-Interactive Delta UPS), these equipment structurally comprise " parallel connection type and tandem type " or " rectifier and inverter " two parts current transformer equipment simultaneously.Take UPQC as example, and its concept is proposed in 1996 by Japanese scholars Akagi the earliest, and after this state scholar such as Japan, the U.S., Germany has carried out further research on initial UPQC conceptual foundation.The basic structure of UPQC is a two way convertor for formula back-to-back, and two parts of two way convertor are distinguished to series and parallel connections in electrical network.The control system of UPQC gathers the voltage and current signal of grid side and load side, calculate the output reference voltage of series connection part current transformer and the output reference current of part current transformer in parallel, generate the electronic power switch control signal of current transformer, series connection part current transformer and part current transformer in parallel are carried out respectively to voltage and current tracking control, make load voltage and power network current maintain sinusoidal waveform.Simultaneously, the direct current capacitor of formula current transformer can also be in parallel with DC energy storage units such as storage batterys back-to-back, when grid side voltage occurs such as catastrophe failures such as voltage fall, UPQC device provides continuous electric energy by part current transformer in parallel for loading during electric network fault.Two changing type UPS are by AC-DC-AC two-stage current transformer structure, realize load and join, the complete voltage of using electricity system, electric current isolation.

Comprehensive D-FACTS functions of the equipments are powerful, can realize the improvement to most type electrical energy power quality disturbances, but at present range of application is still limited, and main limiting factor is that D-FACTS equipment cost is high, anti-overload ability weak and the problem such as poor reliability.Comprehensive D-FACTS comprises in parallel and series connection two parts converter structure simultaneously, and for parallel connection type or tandem type equipment, its holistic cost obviously increases.The same with tandem type D-FACTS equipment, the series converter equipment of comprehensive D-FACTS must design according to maximum overload multiple and the most serious form factor of line load, this contradiction existing between reliability and economy often causes the design capacity of D-FACTS equipment further to increase, the further decline of installation cost and utilance.In addition, comprehensive D-FACTS equipment lacks when circuit is short-circuited to fault short circuit current is suppressed to means effectively.

In the judgement context of detection of grid disturbance, existing people is divided into 3 types by electric network fault at present: fault type I, be also called line short fault type, and refer in protected tail end line or load side serious overload or short trouble occur; Fault type II, also be called instantaneous/temporary transient/short time voltage change type, comprise that any single-phase, two-phase or three-phase voltage dynamic electric voltage jump (swells), the voltage failure type such as voltage collapse (Sags), potential pulse (Impulses), voltage oscillation (Oscillation) and instantaneous power failure (Momentary Interruptions); Fault type III, is also called long-term or stationary power quality type, comprises the power quality events such as term Voltage change, voltage fluctuation and flickering, imbalance, harmonic wave.

The decision condition of 3 kinds of fault types is described as follows:

1) fault type I decision condition: adopt the recognition methods based on load current instantaneous value size and slope.Line current instantaneous value can not suddenly change, and adopts merely instantaneous value to know the requirement that method for distinguishing may can't meet quick identification, therefore increase the identification of line current slope.The impact on load current instantaneous value slope for fear of switched capacitor and harmonic wave, the mode that therefore adopts load current instantaneous value and slope to combine.If the load current instantaneous value that detection computations obtains is i _l, rate of change is di _l/ dt, the decision condition of fault type I is

In formula, i _maxfor current instantaneous value judgement short circuit current threshold value, D _maxfor the electric current slope higher limit based on the judgement of electric current slope.

2) fault type II decision condition: use " derivative algorithm " to calculate the amplitude V of test point three-phase line voltage _sa, V _sb, V _sc.If any phase voltage amplitude detected, exceed prescribed limit, think that system has occurred that voltage falls, the instantaneous voltage failure problem such as voltage oscillation or potential pulse, the i.e. decision condition of fault type II:

$V_{\mathrm{sk}}\∉[V_{\min },V_{\max }],k=a,b,c---\left(2\right)$ Wherein, V _minand V _maxbe respectively the voltage magnitude upper and lower bound of regulation.

Derivative algorithm calculates PCC ₁the formula of some three-phase line voltage is as follows:

$V_{\mathrm{sk}}=\sqrt{u_{\mathrm{sk}}^2+{({\mathrm{du}}_{\mathrm{sk}}/\mathrm{dt})}^2/{\mathrm{\ω}}_0^2},k=a,b,c---\left(3\right)$

Wherein, u _sa, u _sb, u _scbe respectively test point three-phase voltage instantaneous value; Du _sa/ dt, du _sb/ dt, du _sc/ dt is respectively the three-phase voltage instantaneous value rate of change calculating; ω ₀first-harmonic angular frequency for system.

3) fault type III decision condition: fault type III comprises the power quality event of voltage and current type simultaneously, below just respectively the decision method of each power quality event is introduced.

A. harmonic component: the three-phase load current instantaneous value i that control system obtains sampling _la, i _lb, i _lccarry out fast Fourier transform, according to each harmonic component size in load current, judge whether the limit value that is above standard.

B. idle component and negative sequence component: according to i _la, i _lb, i _lcthe three-phase current fundamental phasors obtaining after fast Fourier transform the negative phase-sequence and the zero-sequence component that calculate three-phase load electric current, formula is as follows:

$\left[\begin{array}{c}{\stackrel{\·}{I}}_{\mathrm{La}0}\\ {\stackrel{\·}{I}}_{\mathrm{La}1}\\ {\stackrel{\·}{I}}_{\mathrm{La}2}\end{array}\right]=\frac{1}{3}\left[\begin{array}{ccc}1& 1& 1\\ 1& a& a^2\\ 1& a^2& a\end{array}\right]\·\left[\begin{array}{c}{\stackrel{\·}{I}}_{\mathrm{La}}\\ {\stackrel{\·}{I}}_{\mathrm{Lba}}\\ {\stackrel{\·}{I}}_{\mathrm{Lc}}\end{array}\right],a=e^{j\frac{2\mathrm{\π}}{3}}---\left(4\right)$

C. voltage flicker: the PCC that control system obtains according to sampling ₁the instantaneous value u of some three-phase voltage _sa, u _sb, u _sc, use square examination method (square demodulation, SD) to judge whether to exist voltage flicker.

Summary of the invention

The object of the invention is for overcoming the deficiencies in the prior art, a kind of Unified Power Quality Controller (Unified Power Quality Controller with Resonant Electronic Switch, UPQC-RES) and control method thereof of utilizing mode of resonance electronic switch is provided.The present invention joining with the same round Realization of comprehensive D-FACTS equipment, using electricity system power quality problem is unified administer in, also possesses the inhibit feature to line fault electric current, and possess simple in structure, with low cost, the advantage that anti-overload ability is strong, operational efficiency is high, can effectively advance application process and the scope of application of third generation DFACTS equipment.

For achieving the above object, the unified quality of power supply control device UPQC-RES that utilizes a kind of mode of resonance electronic switch to realize that the present invention proposes, it is characterized in that: this is unified quality of power supply control device and comprises mode of resonance electronic switch, voltage source converter energy-storage units and the master control system being formed by master controller and multiple sensors; Wherein, between mode of resonance electronic switch series connection access electrical network and protected sensitive load, the two-port of mode of resonance electronic switch is respectively PCC ₁point and PCC ₂point; Voltage source converter ac output end mouth access in parallel PCC ₂point, its DC bus capacitor port connects with the corresponding output port of energy-storage units respectively; Master controller input port is connected with each node transducer, gathers respectively PCC ₁point and PCC ₂direct voltage and the DC current signal of the voltage and current signal of point, the output current signal of voltage source converter and energy-storage units output; Master controller output is connected with each electronic power switch control end in voltage source converter and mode of resonance electronic switch respectively, the switching pulse signal of the switching pulse signal of output voltage source current transformer and mode of resonance electronic switch; This mode of resonance electronic switch comprises one group of resonant inductance L _r1, one group of current-limiting inductance L _r2, one group of resonant capacitance C _r1, series capacitance C _r2and one group of bidirectional thyristor T ₁form; Wherein, bidirectional thyristor T ₁with current-limiting inductance L _r2with resonance capacitor C _r1branch road and resonant inductance L that series connection forms _r1connection parallel with one another, described L _r1, L _r2, C _r1, T ₁the parallel branch and the series capacitance C that form _r2series connection mutually.

Described voltage source converter, full-control type power electronic switching device, consist of, topological structure can adopt 2 level three-phase bridge converters, or diode neutral point clamp type 3 level three-phase bridge converters, or 3 single-phase H bridge constructions, or any of the many level current transformers of tandem type H bridge.This voltage source converter possesses voltage-type and controls and two kinds of patterns of current-mode control;

Described energy-storage units, consists of the energy-storage units energy-storage units such as super capacitor, flywheel or battery pack and auxiliary power electronic circuit thereof, the function of realize storage of electrical energy, charging and active power is provided to voltage source converter to internal power storage unit energy-storage units.

Described master control system mainly forms by master controller and with the multiple sensors being connected.Described multiple sensors comprises PCC ₁point voltage instrument transformer group PT ₁, PCC ₂point voltage instrument transformer group PT ₂, PCC ₁dot system current transformer group CT ₁, PCC ₂point current transformer group CT ₂, voltage source converter DC capacitor voltage transducer group PT ₃, energy-storage units output current transducer group CT ₃with voltage source converter output current transducer group CT ₄.Each transducer respectively to joining, using electricity system key node voltage, current and the crucial electrical node of UPQC-RES self detect in real time; Master controller is comprised of dsp chip and fpga chip, and wherein, dsp chip is realized system-level control, calculating, protection and management, and fpga chip is realized AD controlling of sampling, pwm pulse output and unit protection.Master control system calculates in real time and judges and current power quality event type adopts corresponding quality of power supply operational mode according to power quality event Type Control UPQC-RES device.

The progress control method based on described UPQC-RES device that the present invention proposes, is characterized in that: master control system passes through PCC ₁point and PCC ₂the trend of point detects, and various power quality events will be detected and differentiates rear and be divided into 3 types, and accordingly UPQC-RES is set as to 4 kinds of operational modes, judges and controls UPQC-RES and switch fast and move between described 4 kinds of patterns.

4 kinds of operational modes of described UPQC-RES comprise: fault current limitation pattern I, uninterrupted power supply pattern II, shunt compensation pattern III and standby mode IV.

Described contrive equipment progress control method specifically comprises the following steps:

1) gather each sensor signal, comprising: PCC ₁dot system voltage V _s, PCC ₂point load voltage V _l, PCC ₁dot system current i _s, PCC2 point loaded line current i _land energy-storage units output current and output voltage, voltage source converter output current;

2) according to described fault type I, II, III decision condition, judge whether to exist power quality event; If so, go to step 3), otherwise enter standby mode IV and enter step 1);

3) distinguish fault type, according to the priority level of fault type, contrive equipment is switched to corresponding operational mode fast;

4) entering selected operational mode has confirmed, after corresponding operating, to go to step 1).

Described step 3) in, according to the priority level of fault type, to installing, be switched to fast corresponding operational mode, specifically comprise:

Master control system carries out pattern switching according to the priority of 3 kinds of fault types, sets priority to be: fault type I> fault type II> fault type III.

According to described fault type priority, the switching principle of UPQC-RES operational mode is:

No matter which kind of pattern device is currently operating at, and when device detects the high fault type of the fault type priority of administering than present mode of operation, is switched to immediately the operational mode corresponding with higher priority fault type; After the higher fault type recovering state of priority, master control system judges whether the fault type that exists priority lower successively, to determine switch mode type; When 3 kinds of fault types all do not detect, switch and enter standby mode IV.

Compared to the prior art, feature of the present invention and beneficial effect are:

The present invention is a kind of comprehensive electric energy quality compensating device, can be according to the 3 class different faults types that detect, be operated in respectively fault current limitation pattern I, uninterrupted power supply pattern II and shunt compensation pattern III, realize and suppress rapidly fault current and to comprising the comprehensive regulation of voltage-type and current mode power quality problem, solve most power quality problems comprehensively.These abatement functions comprise: join, the quality of voltage problem such as using electricity system generation voltage dip, voltage jump, the temporary transient interruption of voltage; The power quality problems such as the current quality problems such as harmonic current, reactive current, negative-sequence current and the voltage fluctuation causing and flickering; Load and join, by the electric line short circuit current problem that fault causes that is short-circuited.Production process interruption, loss of vital data, the important load reliability that can avoid on the one hand due to voltage dip and interrupt in short-term causing are lost the heavy losses that cause; Can meet on the other hand the quality of power supply causing due to problems such as nonlinear-loads in electric power system and production process and pollute, the impact on index examination or production process; Finally, the fault current limitation function that utilizes multiple spot to distribute, can also avoid the large area voltage that distribution system point short trouble causes to fall, improved to the full extent join, power supply quality and the reliability of using electricity system, and then create considerable economic benefit.

UPQC-RES has overcome the defect that conventional single parallel connection type or tandem type D-FACTS equipment cannot solve current mode and voltage-type electrical energy power quality disturbance simultaneously, as helpless to faults such as voltage fall in parallel connection type D-FACTS devices such as typical APF, DSTATCOM, and the tandem type D-FACTS equipment such as typical DVR device can be realized the improvement to quality of voltage, but cannot realize the control to current.Especially DVR device, also exists when there is the voltage interruption accidents such as system prime circuit breaker back brake or tripping operation, the defect that DVR cannot complete loop cannot play a role.

The present invention has also overcome existing comprehensive D-FACTS equipment and has comprised " parallel connection type and tandem type " or " rectifier and inverter " two parts current transformer equipment simultaneously, the shortcoming such as cost is high, overload capacity is poor and control model is complicated, UPQC-RES only adopts parallel connection type current transformer part, cooperation reliability is high, overload capacity is extremely strong and lower-cost mode of resonance electronic switch, under described control method, realize the abatement functions of comprehensive D-FACTS equipment, also increased the function of fault current limitation simultaneously.

The existing comprehensive electric energy quality controller of comparing, UPQC-RES is simple in structure, with low cost, cost performance is high.Only being equivalent to has increased a set of mode of resonance electronic switch at conventional shunt compensation equipment or series compensation equipment, separate unit cost is only a little more than the APF equipment of same capability, but the function that simultaneously possesses APF, D-STATCOM, DVR, UPS and FCL, has superiority of effectiveness.

Anti-overload ability of the present invention is strong, reliability is high, owing to only adopting parallel converters, does not have the two-stage topology of " AC-DC, DC-AC " in two changing type UPS equipment and the tandem type current transformer in traditional UPQC device and delta type UPS.Adaptability for load abnormal overload ability strengthens greatly, has reduced maintenance cost, and on-the-spot adaptability and operational reliability are higher, can effectively advance application process and the scope of application of third generation DFACTS equipment.

Apparatus of the present invention are when switching enters fault current limitation pattern or uninterrupted power supply pattern, utilize thyristor to trigger the device property of instant conducting, to load circuit and electrical network of structure LC antiresonant circuit isolated, the mode that replaces in prior art shutoff naturally or force the pass break thyristor, compare to the switching time of the common 4～6ms of Line interaction UPS equipment, after the present invention can make system voltage break down by design electronic resonance switch parameter, load voltage can be at 2.0ms with interior recovery, and the steady operation loss of device is suitable with online interaction formula UPS, with the obvious advantage.

Operational efficiency of the present invention, higher than existing comprehensive compensation equipment, due to UPQC-RES overwhelming majority operating condition, only realizes the compensation to target current trend by single convertor, therefore than adopting the comprehensive compensation equipment efficiency of double convertor obviously to improve.

The present invention makes full use of short period overload capability, design capacity is little.In long-time running, can select standby mode or shunt compensation pattern, design capacity is only considered harmonic wave, idle, negative phase-sequence trend capacity; UPS pattern is fallen compensation for the voltage of typical 0～3s, and stored energy capacitance is little, and makes full use of current transformer short period overload capability, makes full use of design capacity.

Accompanying drawing explanation

Fig. 1 is a kind of structure drawing of device that utilizes the unified quality of power supply control device UPQC-RES of mode of resonance electronic switch proposed by the invention.

Fig. 2 is the control flow chart of apparatus of the present invention master control system.

Fig. 3 is the operational mode switch logic figure of apparatus of the present invention.

Fig. 4 is the schematic diagram that apparatus of the present invention operate in standby mode IV and shunt compensation pattern III.

Fig. 5 is the schematic diagram that apparatus of the present invention operate in fault current limitation pattern I.

Fig. 6 is the schematic diagram that apparatus of the present invention operate in uninterrupted power supply pattern II.

Fig. 7 is the control block diagram of current transformer 1 under uninterrupted power supply pattern II.

Fig. 8 is the control block diagram of current transformer 1 under shunt compensation pattern III.

Fig. 9 is PCC after load side short trouble and fault recovery ₁point place three-phase current simulation waveform.

Figure 10 is the load voltage simulation waveform of line voltage while falling 90% and while recovering.

Embodiment

The present invention proposes a kind of Unified Power Quality Controller that utilizes mode of resonance electronic switch and progress control method thereof by reference to the accompanying drawings and embodiment be described in detail as follows:

A kind of quality of power supply control device UPQC-RES that utilizes mode of resonance electronic switch that the present invention proposes, it is characterized in that: comprise voltage source converter 1, energy-storage units 2, mode of resonance electronic switch 3 and the master control system 4 being formed by master controller and multiple sensors, as shown in Figure 1.Wherein, between mode of resonance electronic switch series connection access electrical network and protected non-linear sensitive load, the two-port of mode of resonance electronic switch is respectively PCC ₁point and PCC ₂point; Voltage source converter 1 ac output end mouth access in parallel PCC ₂point, its DC bus capacitor port connects with the corresponding output port of energy-storage units 2 respectively; Master controller input is connected with each transducer, input PCC ₁point and PCC ₂direct voltage and the direct current sampled signal of the voltage and current sample signal of point, the output current sampled signal of voltage source converter and energy-storage units output; Master controller output is connected with mode of resonance electronic switch with voltage source converter respectively, the switching pulse signal of the switching pulse signal of output voltage source current transformer 1 and mode of resonance electronic switch 3; Described mode of resonance electronic switch 3, mainly by one group of inductance L _r1, L _r2and capacitor C _r1, series capacitance C _r2and one group of bidirectional thyristor T ₁form; As shown in Figure 1, bidirectional thyristor T ₁with inductance L _r2and capacitor C _r1branch road and inductance L that series connection forms _r1be in parallel, described L _r1, L _r2, C _r1, T ₁the parallel branch and the capacitor C that form _r2mutually after series connection, form mode of resonance electronic switch 3.

Described voltage source converter 1, full-control type power electronic switching device, consist of, adoptable power electronics topological structure includes but not limited to 2 level or 3 level three-phase bridge structures, 3 single-phase H bridge constructions or the many level current transformers of tandem type H bridge (existing known technology).

Described voltage source converter 1 possesses voltage-type and controls and two kinds of patterns of current-mode control.When UPQC-RES processes II class fault type, voltage source converter 1 runs on voltage-type control model, inversion produce with join, using electricity system voltage magnitude is identical, frequency and phase locked power supply offer load circuit; When UPQC-RES processes III class fault type, voltage source converter 1 runs on four-quadrant current-mode control pattern, according to controlling target, produces required load disturbance injection PCC ₂point, realizes the inhibit feature to harmonic wave, idle, negative phase-sequence trend and voltage flicker; Meanwhile, according to the energy storage situation of energy-storage units 2, to its control of charging.

Described energy-storage units 2, by including but not limited to that the energy-storage units energy-storage units such as super capacitor, flywheel, battery pack and auxiliary power electronic circuit thereof form (existing known technology), the function of realize storage of electrical energy, charging and active power is provided to voltage source converter to energy-storage units energy-storage units.

Making UPQC-RES application of installation of the present invention is V in grade of rated voltage _bjoin, using electricity system, the rated power capacity of voltage source converter 1 is S _b, rated current is I _b, synchro angle frequency is ω ₀, respective frequencies rated impedance base value is X _b, and meet relational expression

$X_B=\frac{V_B^2}{S_B}---\left(5\right)$

Inductance L _r1, L _r2, capacitor C _r1, C _r2parameter is chosen: inductance L _r1with capacitor C _r1impedance parameter should meet parallel resonance condition; Inductance L _r2for small inductor, size is inductance L _r10.05 times of inductance value, makes, under the not obvious condition that affects parallel resonance, to reduce thyristor T ₁the impulse current of conducting moment; Capacitor C _rwith inductance L _r1impedance parameter meets series resonance condition; Note inductance L _r1induction reactance is jX _l1, inductance L _r2induction reactance is jX _l2, capacitor C _r1capacitive reactance be-jX _c1, capacitor C _r2capacitive reactance be-jX _c2, inductance L _r1, inductance L _r2, capacitor C _r1, capacitor C _r2induction reactance jX _l1, jX _l2or capacitive reactance-jX _c1,-jX _c2mould value should meet relational expression (6):

$\left\{\begin{array}{c}{X}_{L1}={\mathrm{mX}}_B,m\∈[m_1,m_2]\\ X_{L2}=0.05\·X_{L1}\\ X_{L1}=X_{C1}\\ X_{L1}=X_{C2}\end{array}\right.---\left(6\right)$

(6) in formula, m represents inductance L _r1the mould value X of induction reactance _l1with rated impedance base value X _bratio, m span is at m ₁with m ₂between, conventionally select m ₁=0.2, m ₂=0.33.

Mode of resonance electronic switch 3 foundations are bidirectional thyristor T wherein ₁the difference of on off state, has two kinds of mode of operations: i.e. T ₁parallel resonance pattern and T under conducting state ₁series resonance pattern under off state.When mode of resonance electronic switch 3 is operated in parallel resonance pattern, ignore inductance L _r2impact, the equiva lent impedance mould value X of mode of resonance electronic switch 3 under this pattern _andapproximates infinity, shown in (7), make to load circuit with join, using electricity system forms and to open circuit, in the time of both can being short-circuited fault to load circuit, short circuit current suppresses, also can be joining, electricity consumption side PCC ₁put while there is II class fault PCC ₁point and protected line PCC ₂point disconnects, and guarantees that UPQC-RES provides firm energy to load.

M ₁and m ₂correspond respectively to inductance L _r1and capacitor C _r1when there is parallel resonance state, bear 3～5 times to rated current I _boverload current; Correspondingly, inductance L _r1conventionally should select at least can bear in a short time 5 times to the air-core reactor of rated current.

When mode of resonance electronic switch 3 is operated in series resonance pattern, its equiva lent impedance mould value X _stringbe approximately zero, shown in (8), circuit and join, form short circuit between using electricity system makes to load.

In typical examples, get m=0.2, now air core reactor L _r1and L _r2the steady-state loss producing is suitable with equal capacity thyristor conduction loss, and after system voltage breaks down, device can be no more than 2.0ms in maximum and take interior rapidly as load provides continuous electric energy.

Described master control system 4, mainly forms by master controller and with the multiple sensors being connected.Described a plurality of transducer comprises PCC ₁point voltage instrument transformer PT ₁, PCC ₂point voltage instrument transformer PT ₂, PCC ₁dot system Current Transmit ₁, PCC ₂point Current Transmit ₂, voltage source converter 1 DC capacitor voltage transducer PT ₃, energy-storage units output current transducer CT ₃with voltage source converter output current transducer CT ₄.Each transducer respectively to joining, using electricity system key node voltage, current and the crucial electrical node of UPQC-RES self detect in real time; master controller is comprised of dsp chip and fpga chip; wherein; dsp chip is realized system-level control, calculating, protection and management, and fpga chip is realized AD sampling, pwm pulse output and unit protection.Master control system calculates in real time and judges and current power quality event type adopts corresponding quality of power supply operational mode according to power quality event Type Control UPQC-RES device.

The progress control method based on described UPQC-RES device that the present invention proposes, is characterized in that: master control system 4 passes through PCC ₁point and PCC ₂the trend of point detects, and various power quality events will be detected and differentiates rear and be divided into 3 types, and accordingly UPQC-RES is set as to 4 kinds of operational modes, judges and controls UPQC-RES and switch fast and move between described 4 kinds of patterns.

3 types of described power quality event comprise: fault type I, be also called line short fault type, and refer in protected tail end line or load side serious overload or short trouble occur; Fault type II, also be called instantaneous/temporary transient/short time voltage change type, comprise that any single-phase, two-phase or three-phase voltage dynamic electric voltage jump (swells), the voltage failure type such as voltage collapse (Sags), potential pulse (Impulses), voltage oscillation (Oscillation) and instantaneous power failure (Momentary Interruptions); Fault type III, is also called long-term or stationary power quality type, comprises the power quality events such as term Voltage change, voltage fluctuation and flickering, imbalance, harmonic wave.

4 kinds of operational modes of described UPQC-RES comprise: fault current limitation pattern I, uninterrupted power supply pattern II, shunt compensation pattern III and standby mode IV.

Described fault current limitation pattern I: refer to when master control system 4 detects fault type I, control mode of resonance electronic switch 3 and run on parallel resonance state, rapidly fault current is limited, simultaneously to voltage source converter 1 pulse blocking; When short trouble being detected, excise, extinguish bidirectional thyristor T ₁trigger impulse, to be confirmed its naturally closes to have no progeny and can enter standby mode; If short trouble fails to excise in time, open failure line switching, avoids the short trouble scope of distribution system further to expand immediately;

Described uninterrupted power supply pattern II: refer to when master control system 4 detects fault type II, lock rapidly fault previous moment PCC ₁voltage magnitude and the phase place of point; Control mode of resonance electronic switch 3 and run on parallel resonance state, control the inverter mode that voltage source converter 1 is operated in voltage-type control model simultaneously, shift active power offer the lasting electric energy of load circuit from energy-storage units 2, whole process is guaranteed PCC ₂voltage magnitude, the phase place of point voltage before and after breaking down is continuous.The single continuous working period of this mode of operation depends on stored energy capacitance and the load capacity of trunk of energy-storage units, and it is 0～3s that representative value arranges conventionally; Master control system 4 is from fault type II being detected to PCC ₂can be controlled in 2.0ms the switching time that point voltage returns between normal waveform.

Described shunt compensation pattern III: refer to when master control system 4 detects fault type III, control mode of resonance electronic switch 3 and operate in series resonance state or incomplete series resonance state; Master control system 4, according to Compensation Objectives computing reference offset currents such as idle, harmonic wave, negative phase-sequences, is controlled voltage source converter 1 and is operated in four-quadrant current-mode control pattern, and compensate according to reference current Injection Current simultaneously; In addition, master control system 4 can be to energy-storage units 2 control of charging under this pattern.

Described standby mode IV, refer to when master control system 4 does not detect any in 3 kinds of fault types, control mode of resonance electronic switch 3 and operate in series resonance or incomplete series resonance state, and control the control of charging of 1 pair of energy-storage units 2 of voltage source converter, when energy-storage units 2 does not need to charge, voltage source converter 1 is in pulse blocking.

The concrete control flow of described progress control method as shown in Figure 2, comprises the following steps:

5) gather each sensor signal, comprising: PCC ₁dot system voltage V _s, PCC ₂point load voltage V _l, PCC ₁dot system current i _s, PCC2 point loaded line current i _land energy-storage units 2 output currents and output voltage, voltage source converter 1 output current;

6) according to described fault type I, II, III decision condition, judge whether to exist power quality event; If so, go to step 3), otherwise enter standby mode IV and enter step 1);

7) distinguish fault type, according to the priority level of fault type, contrive equipment is switched to corresponding operational mode fast;

8) entering selected operational mode has confirmed, after corresponding operating, to go to step 1).

Described step 3) in, according to the priority level of fault type, to installing, be switched to fast corresponding operational mode, specifically comprise:

Master control system carries out pattern switching according to the priority of 3 kinds of fault types, sets priority to be: fault type I> fault type II> fault type III.

According to described fault type priority, the switching principle of UPQC-RES operational mode is:

No matter which kind of pattern device is currently operating at, and when device detects the high fault type of the fault type priority of administering than present mode of operation, is switched to immediately the operational mode corresponding with higher priority fault type; After the higher fault type recovering state of priority, master control system 4 judges whether the fault type that exists priority lower successively, to determine switch mode type; When 3 kinds of fault types all do not detect, switch and enter standby mode IV.

The condition of three kinds of fault type judgements is designated as respectively to condition I, condition II and condition III, the operation switch logic of apparatus of the present invention is as shown in Figure 3.The meaning of Fig. 3 Chinese and English character representative is as shown in table 1.

Operational mode switching condition explanation in table 1 Fig. 3 (√ represents to meet, * foot with thumb down ,-represent irrelevant)

Described step 4) enter selected operational mode and carry out corresponding operating, specifically comprise:

1) when UPQC-RES enters fault current limitation pattern I: master control system 4 is triggering and conducting bidirectional thyristor T immediately ₁, make inductance L _r1with capacitor C _r1form antiresonant circuit, mode of resonance electronic switch is in synchro angle frequencies omega ₀under equiva lent impedance from X _stringbecome X _and, and then fault current is limited in rapidly below the part of rated current; Block the electronic power switch pulse of voltage source converter 1 with protective device itself simultaneously.When short trouble being detected, excise, extinguish bidirectional thyristor T ₁trigger impulse, and confirm that it turn-offs naturally; If short trouble is excision in time not, control disconnecting consumers line switching, avoid the further expansion of fault coverage; According to UPQC-RES operational mode switching principle carry out work thereafter;

2) when UPQC-RES enters uninterrupted power supply pattern II: master control system 4 is triggering and conducting bidirectional thyristor T immediately ₁, make inductance L _r1with capacitor C _r1form antiresonant circuit, mode of resonance electronic switch 3 is in synchro angle frequencies omega ₀under equiva lent impedance from X _stringbecome X _and, at PCC ₁with PCC ₂between 2, form approximates infinity impedance, will join, using electricity system fault end and load circuit isolation.Meanwhile, master control system 4 will be judged fault type II previous moment PCC at once ₁voltage V _samplitude and phase place locking, control voltage source converter 1 at PCC ₂point produces and voltage V _sthe load voltage V of amplitude, the complete slitless connection of phase place _l, the electric energy that utilizes energy-storage units 2 storage provides energy for line load.When UPQC-RES detect that fault type II has recovered or the maximum discharge electrode that reaches energy-storage units 2 in limited time, master control system 4 extinguishes bidirectional thyristor T ₁trigger impulse wait for that it turn-offs naturally, mode of resonance electronic switch enters series resonance or incomplete series resonance state; According to UPQC-RES operational mode switching principle, carry out work immediately;

3) when UPQC-RES enters shunt compensation pattern III: master control system 4 is controlled bidirectional thyristor T ₁in off state, make inductance L _r1with capacitor C _r2form series resonance or incomplete series resonance state; Master control system 4 detects PCC ₁dot system current i _sand extract i _sin idle component, negative sequence component, harmonic component, according to Compensation Objectives, control voltage source converter 1 and produce target component and inject PCC ₂, realize the compensation to the power quality problem of fault type III.Master control system 4 detects the energy storage situation of energy-storage units 2 simultaneously, judges when its energy storage is not enough and passes through voltage source converter 1 from PCC ₂point absorbs active power to the energy-storage units control of charging.When the recovery of fault type III problem being detected, master control system 4 is controlled UPQC-RES and is carried out work according to operational mode switching principle.

Below in conjunction with accompanying drawing and an electric pressure 380V, the UPQC-RES device embodiment of capacity 100kVA describes the specific embodiment of the present invention.

The device example structure of the present invention proposes a kind of unified quality of power supply control device UPQC-RES that utilizes mode of resonance electronic switch as shown in Figure 1.Device is by voltage source converter 1, energy-storage units 2, and mode of resonance electronic switch 3 and master control system 4 form.Wherein, between mode of resonance electronic switch 3 series connection access electrical networks and band protection load, two-port is respectively PCC ₁point and PCC ₂point; Voltage source converter 1 ac output end mouth access in parallel PCC ₂point, its DC bus capacitor port connects with the corresponding output port of energy-storage units 2 respectively.Application of installation is when low pressure occasion (380V system), and voltage source converter can be used 2 level, 3 level three-phase bridge structures or 3 single-phase H bridge constructions, N=1 in corresponding diagram 1; When application of installation and high pressure occasion (6kV, 10kV system), voltage source converter can be used the many level current transformers of tandem type H bridge, N>1 and be integer in corresponding diagram 1.Master control system 4 gathers PCC ₁dot system voltage V _s, PCC ₂point load voltage V _l, PCC ₁dot system current i _s, PCC2 point loaded line current i _land energy-storage units 2 output currents and output voltage, voltage source converter 1 output current, energy-storage units output dc voltage U _dCwith direct current i _dC, the switching pulse signal of the switching pulse signal of output voltage source current transformer 1 and mode of resonance electronic switch 3.

The voltage providing according to the present embodiment and capacity base value can calculate impedance base value and current effective value base value, as follows

$V_B=380V,S_B=100\mathrm{kVA},X_B=V_B^2/S_B=1.44\mathrm{\Ω},I_n=S_B/\sqrt{3}{V}_B=152A---\left(9\right)$

The voltage-source type current transformer 1 of the present embodiment is selected to adopt three-phase 2 level structures, and DC terminal voltage is set as 700V, and output reactance size is made as 0.1pu.

Energy-storage units 2 is selected 20 groups of bank of super capacitors and charge-discharge circuits thereof that 220 super capacitors are monomer series-connected.Capacitor group operating voltage 590V, total capacitance size 9.09F, each super capacitor monomer operating voltage 2.7V, capacitance size 100F, sustained ceiling current 11A.Charge-discharge circuit input voltage range is direct current 460V～590V, and output voltage is direct current 700V.This energy-storage units design parameter can provide for load the back-up source of power output 100kW, power supply duration 6.4s.

Inductance L in mode of resonance electronic switch 3 _r1with capacitor C _r1induction reactance (capacitive reactance) size be set as respectively X _l1=0.2pu, X _c1=-0.2pu.Inductance L _r2reactance value is set as X _l2=0.01pu, series capacitance C _r2capacitive reactance size be set as X _c2=-0.2pu.Bidirectional thyristor T ₁withstand voltage and resistance to stream is selected respectively 200V/300A.

The controller 4 of the present embodiment UPQC-RES device will detect various power quality problems and be divided into 3 types, comprise: fault type I, also be called line short fault type, refer in protected tail end line or load side serious overload or short trouble occur; Fault type II, also be called instantaneous/temporary transient/short time voltage change type, comprise that any single-phase, two-phase or three-phase voltage dynamic electric voltage jump (swells), the voltage failure type such as voltage collapse (Sags), potential pulse (Impulses), voltage oscillation (Oscillation) and instantaneous power failure (Momentary Interruptions); Fault type III, is also called long-term or stationary power quality type, comprises the power quality problems such as term Voltage change, voltage fluctuation and flickering, imbalance, harmonic wave.Controller 4 is measured PCC ₁dot system voltage V _s, PCC ₂point load voltage V _l, PCC ₁dot system current i _s, PCC2 point loaded line current i _land energy-storage units 2 output currents and output voltage, voltage source converter 1 output current, according to measurement data and three kinds of fault type judges conditions, the fault type of system is judged.

According to 3 class power quality problems, UPQC-RES operational mode is divided into 4 kinds: fault current limitation pattern I, uninterrupted power supply pattern II, shunt compensation pattern III and standby mode IV.UPQC-RES device carries out pattern switching according to the priority of 3 kinds of fault types.Conventionally setting priority is: fault type I> fault type II> fault type III.According to this priority, the switching principle of UPQC-RES operational mode is: no matter which kind of pattern device is currently operating at, when device detects the high fault type of the fault type priority of administering than present mode of operation, be switched to immediately the operational mode corresponding with higher priority fault type; After the higher fault type recovering state of priority, controller 4 judges whether the fault type that exists priority lower successively, to determine switch mode type; When 3 kinds of fault types all do not detect, switch and enter standby mode IV.

Controller 4 passes through PCC ₁point and PCC ₂the trend of point detects, and judges quality of power supply type and control UPQC-RES switch fast and move between described 4 kinds of patterns.Control sequential flow chart as shown in Figure 2.

The operational mode switch logic figure of apparatus of the present invention as shown in Figure 3.Wherein, each pattern is switched corresponding Rule of judgment referring to the explanation of table 1, and " condition 1 " in table 1, " condition 2 " and " condition 3 " are respectively the decision condition of fault type in 3.

When UPQC-RES device enters standby mode, controller 4 extinguishes bidirectional thyristor T ₁trigger impulse wait for that it turn-offs naturally, mode of resonance electronic switch enters series resonance or not exclusively series resonance state, as shown in Figure 4 (Fig. 4 is the situation that mode of resonance electronic switch enters series resonance).If energy-storage units underfill is electric, the action of the electronic power switch in voltage source converter 1, charges to energy-storage units.If energy-storage units has been full of electricity, block the electronic power switch in voltage source converter 1, avoid switching loss.

When UPQC-RES device enters failure current limit pattern I, controller 4 is triggering and conducting bidirectional thyristor T immediately ₁, make inductance L _r1with capacitor C _r1form antiresonant circuit, mode of resonance electronic switch is in synchro angle frequencies omega ₀under equiva lent impedance from X _stringbecome X _and, and then fault current is limited in rapidly below part rated current; Block the electronic power switch pulse of voltage source converter 1 with protective device itself, as shown in Figure 5 simultaneously.

When UPQC-RES enters uninterrupted power supply pattern II, controller 4 is triggering and conducting bidirectional thyristor T immediately ₁, make inductance L _r1with capacitor C _r1form antiresonant circuit, mode of resonance electronic switch 3 is in synchro angle frequencies omega ₀under equiva lent impedance from X _stringbecome X _and, at PCC ₁with PCC ₂between 2, equivalence forms and to open circuit, and will join, using electricity system fault end isolates with load circuit, as shown in Figure 6.Meanwhile, controller 4 is according to the PCC judging fault type II time locking ₁voltage V _samplitude and phase place, control voltage source converter 1 at PCC ₂point produces and voltage V _sthe voltage of amplitude, the complete slitless connection of phase place, that utilizes energy-storage units 2 provides energy for line load.Current transformer operates in control method under uninterrupted power supply pattern as shown in Figure 7, and in figure, all signals are three-phase voltage instantaneous value signal.Controller calculates and voltage V _sthe load side voltage reference value u of amplitude, the complete slitless connection of phase place _lref, the load side instantaneous voltage u obtaining with actual measurement _lafter doing difference, carry out proportional integral, the result obtaining operates in the output voltage reference value u under uninterrupted power supply pattern as voltage-source type current transformer 1 _{ref_UPS}.

When UPQC-RES enters shunt compensation pattern III, controller 4 is controlled bidirectional thyristor T ₁in off state, make inductance L _r1with capacitor C _r2form series resonance or incomplete series resonance state, as shown in Figure 4.Controller 4 detects PCC ₁dot system current i _sand extract i _sin idle component, negative sequence component, harmonic component, according to Compensation Objectives, control voltage source converter and produce target component and inject PCC ₂, realize the compensation to the power quality problem of fault type III.Controller 4 detects described mode of resonance electronic switch 3 simultaneously, mainly by one group of inductance L _r1, L _r2and capacitor C _r1, series capacitance C _r2and one group of bidirectional thyristor T ₁form; As shown in Figure 1, bidirectional thyristor T ₁with inductance L _r2and capacitor C _r1branch road and inductance L that series connection forms _r1be in parallel, described L _r1, L _r2, C _r1, T ₁the parallel branch and the capacitor C that form _r2mutually after series connection, form mode of resonance electronic switch 3.The control of charging.Concrete control method is as shown in Figure 8 under shunt compensation pattern for voltage-source type current transformer 1.Wherein, V _drefand V _drepresent respectively current transformer 1 DC voltage reference value and measured value, be the active current i of difference controlled DC voltage after proportional integral _dref.V _srefand V _srepresent respectively PCC ₁the reference value of point voltage effective value and measured value, be the reactive current component i that difference-product divides rear controlled system voltage _qref.Controller 4 is according to the PCC measuring ₁point three-phase voltage instantaneous value u _sphase-lockedly calculate corresponding phase angle theta, meritorious and reactive current component obtains voltage-source type current transformer 1 for the reference current instantaneous value i of voltage-regulation after dq/abc conversion _ref1.Controller 4 is measured load current instantaneous value i _l, carry out fast Fourier transform and obtain load current harmonic component i _h, simultaneously according to formula (4), utilize Fourier transform result to calculate the negative sequence component i of load current _neg, by i _ref1, i _hand i _negstack just can obtain voltage-source type current transformer 1 and operate in the output current reference value i under shunt compensation pattern III _ref.By i _refcurrent transformer 1 output current instantaneous value i with actual measurement _cit is poor to do, and just can obtain voltage-source type current transformer 1 operate in the output voltage reference value u under shunt compensation pattern III through PI integration _{ref_shunt}.

Please refer to shown in Fig. 9.Constantly load side generation of analogue simulation 0.1s metallic short circuit fault, i.e. fault type I, it is 90% that short dot voltage falls the degree of depth, fault duration 0.05s.The parameter of electronic resonance switch is chosen as X _l1=0.2pu, X _c1=-0.2pu, X _l2=0.01pu, X _c2=-0.2pu, load adopts the resistance sense load simulation that power factor is 0.8.In the present embodiment, the decision condition setting parameter of fault type I is i _max1=5.0pu, i _max2=3.0pu, D _max=1.5e ^-3pu/us, corresponding base value is current peak base value, device short-time overload multiple is set as K _overload=1.5, the maximum load current summit coefficient settings allowing is K _h=2.5, obtaining the peak inrush current that auto levelizer can bear is in short-term i _max=I _nk _hk _overload=2.65pu, corresponding base value is current peak base value.The setting that can verify decision condition parameter meets i _max2> i _maxrequirement.UPQC-RES device operated in shunt compensation pattern III before fault, the rear controller of fault generation detects grid side voltage and falls within 0.2ms, switching device shifter operational mode is failure current limit pattern I, 0.15s load voltage recovers, controller detects load voltage and recovers within 0.2ms, and switching device shifter operational mode is shunt compensation pattern III again.Simulation result show during load short trouble can restriction system side electric current in 5.5p.u..

Please refer to shown in Figure 10.Constantly grid side generation of analogue simulation 0.307s voltage falls fault, i.e. fault type II, and voltage falls the degree of depth and is made as 90%, fault duration 0.03s.The parameter of electronic resonance switch is chosen as X _l1=0.2pu, X _c1=-0.2pu, X _l2=0.01pu, X _c2=-0.2pu, load adopts the resistance sense load simulation that power factor is 0.8.The decision condition setting parameter of fault type II is V _min=0.9, V _max=1.2.UPQC-RES device operated in shunt compensation pattern III before fault, after fault occurs, within 0.2ms, controller detects grid side voltage and falls, switching device shifter operational mode is uninterrupted power supply pattern II, 0.334s line voltage recovers, controller detects line voltage and recovers within 0.2ms, and switching device shifter operational mode is shunt compensation pattern III again.Simulation result shows that load voltage receives hardly any impact in whole interval, and voltage switching time is in 2.0ms.

Claims (7)

1. a unified quality of power supply control device that utilizes mode of resonance electronic switch, it is characterized in that: this is unified quality of power supply control device and comprises mode of resonance electronic switch, voltage source converter energy-storage units and the master control system being formed by master controller and multiple sensors; Wherein, between mode of resonance electronic switch series connection access electrical network and protected sensitive load, the two-port of mode of resonance electronic switch is respectively PCC ₁point and PCC ₂point; Voltage source converter ac output end mouth access in parallel PCC ₂point, its DC bus capacitor port connects with the corresponding output port of energy-storage units respectively; Master controller input is connected with each transducer; Master controller output is connected with mode of resonance electronic switch with voltage source converter respectively, the switching pulse signal of the switching pulse signal of output voltage source current transformer and mode of resonance electronic switch; This mode of resonance electronic switch comprises one group of inductance L _r1and L _r2, one group of capacitor C _r1and C _r2and one group of bidirectional thyristor T ₁; Wherein, bidirectional thyristor T ₁with inductance L _r2, capacitor C _r1branch road and inductance L that series connection forms _r1be in parallel, by L _r1, L _r2, C _r1, T ₁the parallel branch and the capacitor C that form _r2series connection mutually.

2. install as claimed in claim 1, it is characterized in that, described voltage source converter adopts any full-control type power electronic switching device of 2 level, 3 level three-phase bridge structures, 3 single-phase H bridge constructions or the many level current transformers of tandem type H bridge to form, and possesses voltage-type and controls and two kinds of patterns of current-mode control.

3. install as claimed in claim 1, it is characterized in that, described energy-storage units consists of super capacitor, flywheel or battery energy storage unit energy-storage units and auxiliary power electronic circuit thereof, realizes storage of electrical energy, to energy-storage units energy-storage units, charges and provide active power to voltage source converter.

As claimed in claim 1 device, it is characterized in that, described master control system comprise master controller and with the multiple sensors being connected; Described a plurality of transducer comprises PCC ₁point voltage instrument transformer PT ₁, PCC ₂point voltage instrument transformer PT ₂, PCC ₁dot system Current Transmit ₁, PCC ₂point Current Transmit ₂, voltage source converter 1 DC capacitor voltage transducer PT ₃, energy-storage units output current transducer CT ₃with voltage source converter output current transducer CT ₄; Each transducer respectively to joining, using electricity system key node voltage, current and utilize the crucial electrical node of unified quality of power supply control device self of mode of resonance electronic switch to detect in real time; Master controller is comprised of dsp chip and fpga chip, and wherein, dsp chip is realized system-level control, calculating, protection and management, and fpga chip is realized AD sampling, pwm pulse output and unit protection; Master control system calculates in real time and judges current power quality event type, according to power quality event Type Control, utilizes the unified quality of power supply control device of mode of resonance electronic switch to adopt corresponding quality of power supply operational mode.

5. the progress control method based on device described in claim 1, is characterized in that: master control system passes through PCC ₁point and PCC ₂the trend of point detects, various power quality events to be detected differentiates rear and is divided into 3 types, and will utilize the unified quality of power supply control device UPQC-RES of mode of resonance electronic switch to be set as 4 kinds of operational modes accordingly, judge and control UPQC-RES and switch fast and move between described 4 kinds of patterns;

4 kinds of operational modes of described UPQC-RES comprise: fault current limitation pattern I, uninterrupted power supply pattern II, shunt compensation pattern III and standby mode IV.

6. method as claimed in claim 5, is characterized in that, described progress control method specifically comprises the following steps:

1) gather each sensor signal, comprising: PCC ₁dot system voltage V _s, PCC ₂point load voltage V _l, PCC ₁dot system current i _s, PCC2 point loaded line current i _land energy-storage units output current and output voltage, voltage source converter output current;

2) according to described fault type I, II, III decision condition, judge whether to exist power quality event; If so, go to step 3), otherwise enter standby mode IV and enter step 1);

3) distinguish fault type, according to the priority level of fault type, contrive equipment is switched to corresponding operational mode fast;

4) entering selected operational mode has confirmed, after corresponding operating, to go to step 1).

7. method as claimed in claim 6, is characterized in that described step 3) in, according to the priority level of fault type, to installing, be switched to fast corresponding operational mode, specifically comprise:

Master control system carries out pattern switching according to the priority of 3 kinds of fault types, sets priority to be: fault type I> fault type II> fault type III;

According to described fault type priority, the switching principle of UPQC-RES operational mode is:

No matter which kind of pattern device is currently operating at, and when device detects the high fault type of the fault type priority of administering than present mode of operation, is switched to immediately the operational mode corresponding with higher priority fault type; After the higher fault type recovering state of priority, master control system judges whether the fault type that exists priority lower successively, to determine switch mode type; When 3 kinds of fault types all do not detect, switch and enter standby mode IV.