CN103354363B - A kind of take bulk power grid as the microgrid power balance control method of virtual energy storage - Google Patents

Abstract

The present invention relates to a kind of take bulk power grid as the microgrid power balance control method of virtual energy storage, the method is for virtual energy storage system with the bulk power grid be connected with micro-capacitance sensor, when distributed power source output power in micro-capacitance sensor is not enough, from bulk power grid, absorbed power is that micro-capacitance sensor internal loading is powered, when distributed power source output power in micro-capacitance sensor exceeds micro-capacitance sensor internal load power demand, by microgrid power regulating system, control exerting oneself of distributed power source, make the strict coupling micro-capacitance sensor internal load of exerting oneself of distributed power source, thus make distributed power source in micro-capacitance sensor flow to the power output of bulk power grid lower than setting threshold, this method can be real-time balanced distribution formula power supply exert oneself and micro-capacitance sensor internal loading size, reduce the permeability of distributed power source in bulk power grid to greatest extent, inhibit possible distributed power source to the pollution of the bulk power grid quality of power supply, for the popularization of distributed power source application is laid a good foundation.

Description

A kind of take bulk power grid as the microgrid power balance control method of virtual energy storage

Technical field

The invention belongs to micro-capacitance sensor control technology field, relating to a kind of take bulk power grid as the microgrid power balance control method of virtual energy storage.

Background technology

Along with conventional energy resource crisis and Against Global Climate Changes become increasingly conspicuous; renewable distributed energy is as swift and violent in the growth momentum such as wind energy and solar energy; simultaneously along with the continuous expansion of electrical network scale; the drawback of ultra-large electric power system also shows especially day by day; as run difficulty large, be difficult to meet the more and more higher reliability of user and diversified need for electricity etc.; in view of the above problems, Chinese scholars starts extensively to study distributed generation technology.Distributed electrical source position flexibly, dispersion, can be for subsequent use each other with electrical network, shared the function of power transmission network and bulk power transmission remote from power plant to user to a certain extent.But relative to electrical network, distributed power source is a uncontrollable power supply, its a large amount of access can affect to electrical network, and therefore, bulk power grid also often limits or isolation distributed power source.In order to coordinate the contradiction of bulk power grid and distributed power source, the concept of micro-capacitance sensor is suggested and is developed.Micro-capacitance sensor, by combinations such as micro power, load, energy storage device and control device, forms a unit in electrical network, carries out energy exchange by points of common connection (PCC) and electrical network.In micro-capacitance sensor, distributed power generation has intermittence and probabilistic feature, the fluctuation of micro-capacitance sensor internal loading is also larger, the cost that micro-capacitance sensor builds energy storage is current also higher, or possessed energy storage but energy-storage system can not meet the requirement of the peak load that disappears, the energy in micro-capacitance sensor may deliver to electrical network.Larger permeability and the quality of power supply of distributed power source can cause larger impact to electrical network, and this is that current distributed power source and micro-capacitance sensor build Problems existing.

Summary of the invention

The object of this invention is to provide a kind of take bulk power grid as the microgrid power balance control method of virtual energy storage, to solve the quality of power supply of the larger permeability of current micro-capacitance sensor and distributed power source to the problem affected greatly in electrical network.

For achieving the above object, of the present invention is that the microgrid power balance control method technical scheme of virtual energy storage is as follows with bulk power grid: the method is for virtual energy storage system with the bulk power grid be connected with micro-capacitance sensor, when distributed power source output power in micro-capacitance sensor is not enough, from bulk power grid, absorbed power is that micro-capacitance sensor internal loading is powered, when distributed power source output power in micro-capacitance sensor exceeds micro-capacitance sensor internal load power demand, by microgrid power regulating system, control exerting oneself of distributed power source, the gross capability of distributed power source and micro-capacitance sensor internal load are matched, thus make distributed power source in micro-capacitance sensor flow to the power output of bulk power grid lower than setting threshold.

Further, in described micro-capacitance sensor, the detection that is not enough or that exceed of distributed power source output power to be flowed to and Power Exchange size obtains in meritorious, the reactive power that detect points of common connection place by checkout gear.

Further, between micro-capacitance sensor and bulk power grid, the condition of Power Exchange is:

$\left\{\begin{array}{c}{P}_{\mathrm{MGLOAD}}=P_{\mathrm{MGDG}}+P_G\\ Q_{\mathrm{MGLOAD}}=Q_{\mathrm{MGDG}}+Q_G\\ P_G\≥0\\ Q_G\≥0\end{array}\right.$

Wherein P _mGLOAD: active load in micro-capacitance sensor;

Q _mGLOAD: reactive load in micro-capacitance sensor;

P _mGDG: the active power that in micro-capacitance sensor, distributed power source provides;

Q _mGDG: in micro-capacitance sensor, distributed power source and compensation equipment provide reactive power;

P _g: the active power that the bulk power grid of virtual energy storage provides;

Q _g: the reactive power that the bulk power grid of virtual energy storage provides; And P _g, Q _gmicro-capacitance sensor is entered for positive direction with bulk power grid poower flow.

Further, when distributed power source output power in micro-capacitance sensor exceeds micro-capacitance sensor internal load power demand, namely, when generation power flow direction flows to bulk power grid by micro-capacitance sensor, backward power signal and backward power value are uploaded to microgrid power regulating system by rapid communication network by checkout gear.

Further, checkout gear arranges a backward power threshold threshold value, and in conjunction with safety factor and resetting ratio, when direction component action and backward power be greater than threshold threshold value time, checkout gear send microgrid power regulating system relevant information, on the contrary then not on give.

Of the present invention take bulk power grid as the microgrid power balance control method of virtual energy storage, exerting oneself and micro-capacitance sensor internal loading size of balanced distribution formula power supply that can be real-time, reduce the permeability of distributed power source in bulk power grid to greatest extent, inhibit possible distributed power source to the pollution of the bulk power grid quality of power supply, for the popularization of distributed power source application is laid a good foundation.

Accompanying drawing explanation

Fig. 1 is micro-capacitance sensor and the mutual schematic diagram of bulk power grid power;

Fig. 2 is the microgrid power balance control principle drawing of the embodiment of the present invention.

Embodiment

The energy storage device that micro-capacitance sensor is self with the bulk power grid be attached thereto, the implication of virtual energy storage is the stand-by power supply of bulk power grid as micro-capacitance sensor, only conveying micro-capacitance sensor electric energy, and does not accept the feeding electric energy of micro-capacitance sensor.

Take bulk power grid as the microgrid power balance control method of virtual energy storage, with the bulk power grid be connected with micro-capacitance sensor for virtual energy storage system, when distributed power source output power in micro-capacitance sensor is not enough, from bulk power grid, absorbed power is that micro-capacitance sensor internal loading is powered, when the distributed power source output power of micro-capacitance sensor exceeds the power required for micro-capacitance sensor internal load, by microgrid power regulating system, control exerting oneself of distributed power source, exerting oneself of distributed power source is allowed strictly to mate micro-capacitance sensor internal load, thus make the power output of distributed power source in micro-capacitance sensor not flow to bulk power grid.

If Fig. 1 is micro-capacitance sensor and the mutual schematic diagram of bulk power grid power, Fig. 2 is the microgrid power balance control principle drawing of the present embodiment, in Fig. 2, the voltage and current signal at checkout gear (checkout gear carries out the collection of electric parameters and the device of calculating) Real-time Collection PCC place carries out computing, major embodiment two aspect function: one, judge whether to there is backward power by power directional element, and micro-capacitance sensor sends power to bulk power grid; Its two, detect the size of backward power.When power directional element satisfies condition and the power sent is greater than threshold threshold epsilon (ε >0, escape the minimum trueness error of checkout gear, can set) time, the value of signal reverse for power and backward power is delivered to microgrid power balance control system by communication network by checkout gear, is regulated exerting oneself of distributed power source in micro-capacitance sensor by control system.

After microgrid power balance control system receives the power reverse signal that checkout gear send, i.e. starting power regulating system.Though microgrid power balance control system is a closed-loop control system, but requirement of real-time is not high under this application model, for ensureing the reliability regulated, the value that repeated detection device send can be judged continuously, in conjunction with the situation of current micro-grid system internal load, carry out a certain amount of excessive adjustments, namely ensure reliability and the validity of adjustment.The size of excessive adjustments is determined according to concrete requirement.

The concrete steps taking bulk power grid as the microgrid power balance control method of virtual energy storage are as follows:

(1) checkout gear detects the meritorious of points of common connection PCC place in real time, reactive power flows to and Power Exchange size, this power flow direction is detected by the direction component of checkout gear, when there is power flow direction and flowing to bulk power grid by micro-capacitance sensor, checkout gear is by high-speed traffic mode, by direction power signal and backward power value by communication network being delivered to microgrid power balance control system (calculating that namely central processing unit carries out power-balance judges), load mode is transmitted by rapid communication mechanism, to guarantee the requirement meeting powered balance control system (the power controlling functions on the spot of distributed power source) governing response,

(2) after microgrid power balance control system detects backward power signal, starting power balances controlling functions, and the size according to regulated quantity regulates the distributed power source in micro-capacitance sensor;

(3) according to the response time of adjustment and the effect of adjustment, continue the signal judging checkout gear, carry out the control of continuous print closed-loop adjustment;

(4) until checkout gear no longer on send anti-power signal after, a closed-loop control regulate terminate, otherwise continue repeat above-mentioned steps.

In step (1), in order to avoid the repeat function in power mutual Near The Critical Point microgrid power regulating system, checkout gear arranges a backward power threshold threshold values ε, and in conjunction with safety factor K _rel(be greater than 1.0, can set in practical application) and resetting ratio K _ret(be less than 1.0, can set in practical application), when direction component action and backward power is greater than threshold threshold values time (be greater than K _rel* ε), checkout gear send microgrid power regulating system relevant information, otherwise then not on give.

Between micro-capacitance sensor and bulk power grid, the condition of Power Exchange is:

$\left\{\begin{array}{c}{P}_{\mathrm{MGLOAD}}=P_{\mathrm{MGDG}}+P_G\\ Q_{\mathrm{MGLOAD}}=Q_{\mathrm{MGDG}}+Q_G\\ P_G\≥0\\ Q_G\≥0\end{array}\right.$

Wherein P _mGLOAD: active load in micro-capacitance sensor;

Q _mGLOAD: reactive load in micro-capacitance sensor;

P _mGDG: the active power that in micro-capacitance sensor, distributed power source provides;

Q _mGDG: in micro-capacitance sensor, distributed power source and compensation equipment provide reactive power;

P _g: the active power that the bulk power grid of virtual energy storage provides;

Q _g: the reactive power that the bulk power grid of virtual energy storage provides; And P _g, Q _gmicro-capacitance sensor is entered for positive direction with bulk power grid poower flow.

Method of the present invention is real-time regulating method, exerting oneself and microgrid internal loading size of balanced distribution formula power supply that can be real-time, reduce the permeability of distributed power source in bulk power grid to greatest extent, inhibit possible distributed power source to the pollution of the bulk power grid quality of power supply, for basis determined by the popularization pad of distributed power source application.

Claims (3)

1. one kind take bulk power grid as the microgrid power balance control method of virtual energy storage, it is characterized in that, the method is for virtual energy storage system with the bulk power grid be connected with micro-capacitance sensor, when distributed power source output power in micro-capacitance sensor is not enough, from bulk power grid, absorbed power is that micro-capacitance sensor internal loading is powered, when distributed power source output power in micro-capacitance sensor exceeds micro-capacitance sensor internal load power demand, by microgrid power regulating system, control exerting oneself of distributed power source, the gross capability of distributed power source and micro-capacitance sensor internal load are matched, thus make distributed power source in micro-capacitance sensor flow to the power output of bulk power grid lower than setting threshold,

When distributed power source output power in micro-capacitance sensor exceeds micro-capacitance sensor internal load power demand, namely, when generation power flow direction flows to bulk power grid by micro-capacitance sensor, backward power signal and backward power value are uploaded to microgrid power regulating system by rapid communication network by checkout gear;

Checkout gear arranges a backward power threshold threshold value, and in conjunction with safety factor and resetting ratio, when direction component action and backward power is greater than threshold threshold value time, checkout gear send microgrid power regulating system relevant information, on the contrary then not on give.

2. method according to claim 1, is characterized in that, in described micro-capacitance sensor, the detection that is not enough or that exceed of distributed power source output power is that meritorious, the reactive power detecting points of common connection place by checkout gear flows to and Power Exchange size obtains.

3. method according to claim 2, is characterized in that, between micro-capacitance sensor and bulk power grid, the condition of Power Exchange is:

$\left\{\begin{array}{c}{P}_{\mathrm{MGLOAD}}=P_{\mathrm{MGDG}}+P_G\\ Q_{\mathrm{MGLOAD}}=Q_{\mathrm{MGDG}}+Q_G\\ P_G\≥0\\ Q_G\≥0\end{array}\right.$

Wherein, P _mGLOAD: active load in micro-capacitance sensor;

Q _mGLOAD: reactive load in micro-capacitance sensor;

P _mGDG: the active power that in micro-capacitance sensor, distributed power source provides;

Q _mGDG: in micro-capacitance sensor, distributed power source and compensation equipment provide reactive power;

P _g: the active power that the bulk power grid of virtual energy storage provides;

Q _g: the reactive power that the bulk power grid of virtual energy storage provides; And P _g, Q _gmicro-capacitance sensor is entered for positive direction with bulk power grid poower flow.