KR102316744B1 - Method and apparatus for optimizing home energy management system in three-phase unbalanced low-voltage distribution network - Google Patents

Abstract

에 대한 목적함수를 구성하고, 상기 목적함수에 대해 무효 전력 제약 조건, 3상 선형 전압 제약 조건, 전압 의존 부하 모델, 태양광 발전(PV) 및 에너지 저장 시스템(ESS)의 무효 전력, 전압 및 부하 시 탭 절환기 중 적어도 하나를 고려하여 상기 수집된 전력 소비 데이터로부터 가전 제품의 부하 감소 및 부하 쉬프팅을 위한 최적화 해를 계산하도록, 상기 프로세서에 의해 실행되는 프로그램 명령어들을 저장하는 홈 에너지 관리 시스템 최적화 장치가 제공된다.The present invention discloses an apparatus and method for optimizing a home energy management system (HEMS) in a three-phase unbalanced low voltage distribution network. According to this embodiment, a processor; and a memory coupled to the processor, wherein the memory collects power consumption data from each of a plurality of households receiving power from the three-phase unbalanced low voltage distribution network, and is configured to collect power consumption data from each of a plurality of households receiving power from the three-phase unbalanced low voltage distribution network, and to optimize the HMES for a total electricity bill during a scheduling period. and household inconvenience cost, the phase at time t

Construct an objective function for , and reactive power constraint, three-phase linear voltage constraint, voltage-dependent load model, reactive power, voltage and load of photovoltaic (PV) and energy storage system (ESS) for the objective function Home energy management system optimizing device for storing program instructions executed by the processor to calculate an optimization solution for load reduction and load shifting of home appliances from the collected power consumption data in consideration of at least one of the time tap changers is provided

Description

Method and apparatus for optimizing home energy management system in three-phase unbalanced low-voltage distribution network

The present invention relates to a method and apparatus for optimizing a home energy management system in a three-phase unbalanced low voltage distribution network.

As residential households account for one-third of total electricity consumption, Home Energy Management System (HEMS) has become an essential technology for efficient and economical energy management.

The main goal of HEMS is to reduce electricity costs while ensuring comfort by scheduling optimal energy consumption for smart appliances (eg air conditioners and washing machines, etc.).

More recently, distributed energy resources (DERs, such as roof solar photovoltaic (PV) and Energy Storage Systems (ESS)), advanced metering infrastructure with smart meters and demand management Smart grid technologies that include

The core technology of the conventional HEMS is an optimization method used for economical load reduction and load shifting of smart home appliances in addition to operation scheduling (charging/discharging) of the DER.

However, the conventional HEMS optimization algorithm has a problem of inaccuracy due to the following limitations.

First, it does not consider reactive power and only considers active power of home appliances and active power injection/absorption of DER. Load voltage dependence is not taken into account.

In practice, the consumer load varies with voltage, and in these circumstances the conventional HEMS approach ignores the voltage quality for the individual consumer and uses voltage regulators (e.g., on-load tap changers (OLTC) and Volt- There is a problem in that the effect of VAR optimization (VVO) is not considered.

Korean Patent Publication No. 10-2015-0040894

In order to solve the problems of the prior art, the present invention provides a method and apparatus for optimizing a home energy management system in a three-phase unbalanced low voltage distribution network that can reduce electricity costs while ensuring user convenience in consideration of the voltage quality of individual consumers. I would like to suggest

에 대한 목적함수를 구성하고, 상기 목적함수에 대해 무효 전력 제약 조건, 3상 선형 전압 제약 조건, 전압 의존 부하 모델, 태양광 발전(PV) 및 에너지 저장 시스템(ESS)의 무효 전력, 전압 및 부하 시 탭 절환기 중 적어도 하나를 고려하여 상기 수집된 전력 소비 데이터로부터 가전 제품의 부하 감소 및 부하 쉬프팅을 위한 최적화 해를 계산하도록, 상기 프로세서에 의해 실행되는 프로그램 명령어들을 저장하는 홈 에너지 관리 시스템 최적화 장치.In order to achieve the above object, according to an embodiment of the present invention, a home energy management system (HEMS) optimization device in a three-phase unbalanced low voltage distribution network, the processor; and a memory coupled to the processor, wherein the memory collects power consumption data from each of a plurality of households receiving power from the three-phase unbalanced low voltage distribution network, and is configured to collect power consumption data from each of a plurality of households receiving power from the three-phase unbalanced low voltage distribution network, and to optimize the HMES for a total electricity bill during a scheduling period. and household inconvenience cost, the phase at time t

Construct an objective function for , and reactive power constraint, three-phase linear voltage constraint, voltage-dependent load model, reactive power, voltage and load of photovoltaic (PV) and energy storage system (ESS) for the objective function Home energy management system optimizing device for storing program instructions executed by the processor to calculate an optimization solution for load reduction and load shifting of home appliances from the collected power consumption data in consideration of at least one of the time tap changers .

The voltage dependent load model can be defined using the square vector of the three-phase voltage magnitude of generation u at time t, three-phase effective and reactive line flow and line impedance of line uv at time t.

The objective function may be defined as follows for the scheduling period (T).

[Equation]

는 시간 t에 그리드로부터 TOU 기반으로 구입하는 가격,

는 시간 t에서 위상

에 대한 세대 u의 순 유효 전력 소비량,

는 시간 t에 그리드로 TOU 기반으로 판매하는 가격,

는 시간 t에서 위상

에 대한 세대 u의 그리드 공급을 위한 순 유효 전력 소비량,

는 위상

에서 세대 u의 불편 비용에 대한 패널티 파라미터,

는 시간 t에서 위상

에 대한 세대 u의 불편 비용(discomfort cost)임 here,

is the purchase price based on TOU from the grid at time t,

is the phase at time t

net active power consumption of generation u for

is the selling price based on TOU as a grid at time t,

is the phase at time t

net active power consumption for grid supply of generation u for

is the phase

a penalty parameter for the inconvenience cost of generation u,

is the phase at time t

is the inconvenience cost of generation u for

The linearized voltage dependence model for the three-phase active and reactive loads of generation u at time t can be defined as

[Equation]

[Equation]

는

에 대해,

로 표현되고,

와

는 일정한 임피던스, 일정한 전류 및 일정한 유효 및 무효 전력에 대한 전력 부하의 백분율을 나타내는 계수의 셋이며,

와

방정식을 만족시키며,

는 시간 t에서 세대 u의 3상 전압 크기의 제곱 벡터임here,

Is

About,

is expressed as

Wow

is a set of coefficients representing the percentage of power load to constant impedance, constant current and constant active and reactive power,

Wow

satisfies the equation,

is the square vector of the magnitude of the three-phase voltage of generation u at time t

에 대한 목적함수를 구성하는 단계; 및 상기 목적함수에 대해 무효 전력 제약 조건, 3상 선형 전압 제약 조건, 전압 의존 부하 모델, 태양광 발전(PV) 및 에너지 저장 시스템(ESS)의 무효 전력, 전압 및 부하 시 탭 절환기 중 적어도 하나를 고려하여 상기 수집된 전력 소비 데이터로부터 가전 제품의 부하 감소 및 부하 쉬프팅을 위한 최적화 해를 계산하는 단계를 포함하는 홈 에너지 관리 시스템 최적화 방법이 제공된다.According to another aspect of the present invention, there is provided a method for optimizing a home energy management system (HEMS) in a three-phase unbalanced low-voltage distribution network performed by a device including a processor and a memory, wherein a plurality of collecting power consumption data from each household; For the HMES optimization, related to the total electricity cost and household inconvenience cost during the scheduling period, the phase at time t

constructing an objective function for and at least one of reactive power constraint condition, three-phase linear voltage constraint condition, voltage dependent load model, reactive power of photovoltaic (PV) and energy storage system (ESS), voltage and on-load tap-changer for the objective function. There is provided a home energy management system optimization method including calculating an optimization solution for load reduction and load shifting of home appliances from the collected power consumption data in consideration of the.

According to the present invention, a solution for HEMS optimization can be accurately calculated in consideration of a reactive power and voltage-dependent model.

1 is a diagram illustrating a system model for HEMS in an LV distribution feeder.
2 is a diagram showing the configuration of an optimization device according to the present embodiment.

Since the present invention can have various changes and can have various embodiments, specific embodiments are illustrated in the drawings and described in detail.

However, this is not intended to limit the present invention to specific embodiments, and it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

The present invention proposes a voltage-reactive power constraint HEMS optimization framework that can be performed in a three-phase unbalanced power distribution system, and the HEMS optimization according to this embodiment minimizes electricity bills at the comfort level of consumers, to improve the voltage quality for

According to this embodiment, the active and reactive power consumption of the unbalanced voltage dependent load along with the operation of the OLTC and smart inverter of the DER is scheduled to save energy and maintain voltage quality.

In this embodiment, the proposed HEMS optimization algorithm is formulated as a MILP model.

Models for three-phase unbalanced active/reactive power flow, voltage dependent load and OLTC are linearized and these linear equations are incorporated as constraints of the proposed MILP HEMS optimization problem.

Hereinafter, the HEMS optimization algorithm according to the present embodiment will be described in detail with reference to the drawings.

1 is a diagram illustrating a system model for HEMS in an LV distribution feeder.

1 is a diagram illustrating a radial LV distribution network comprising a Medium-Voltage (MV)/Low-Voltage (LV) transformer with OLTC along a distribution feeder and several smart generations.

) 및 일련의 분기(

)를 포함하고, 여기서,

이고,

이다. A distribution feeder is a series of nodes (

) and a series of branches (

), wherein

ego,

am.

) 및 각 선로가 한 쌍의 노드(

)로 구성된다. one node (

) and each line is a pair of nodes (

) is composed of

The smart generation is connected to each node and is assumed to be connected to PV, ESS and smart home appliances.

A plurality of households receiving power from the same LV system form one entity, which is regarded as a community.

In a residential community, consider the situation in which each consumer (household) can exchange energy with the grid according to the TOU rate system.

It is assumed that the distribution system operator can collect power consumption data from consumers in the community.

Therefore, the collected data is used as input data for scheduling the optimal energy consumption of the home by the community HEMS.

In this embodiment, the main function of the HEMS community is to schedule the optimal energy consumption of home appliances and the consumer's power exchange while maintaining the consumer's comfort level and voltage quality within the desired range.

Smart appliances are classified into uncontrollable loads (eg TV, PC and lighting) and controllable loads (eg air conditioners, washing machines and ESSs).

HEMS can only schedule and operate controllable loads.

Both loads consume both active and reactive power, and the reactive power consumption of the load is expressed as the actual power consumption and the power factor. It is assumed that each home's PV system and ESS have individual smart inverters that can regulate the voltage through either active power injection or reactive power injection/absorption into the system. In this LV system, the voltage regulation device is the OLTC transformer and smart inverter of the PV system and the ESS of each home.

Hereinafter, the conventional HEMS optimization algorithm will be first described, and the HEMS optimization algorithm according to the present embodiment will be described in detail.

Prior to formulation, the variables are defined as follows.

: 시간 t에서 세대 u의 순 유효(무효) 전력 소비량

: net active (reactive) power consumption of generation u at time t

: 시간 t에서 세대 u에 의한 그리드로의 순 유효 전력량

: net active power to grid by generation u at time t

: 시간 t에서 세대 u의 불편 비용(discomfort cost)

: Discomfort cost of generation u at time t

: 시간 t에서 세대 u의 총 유효(무효) 부하 전력 소비량

: total active (reactive) load power consumption of generation u at time t

: 시간 t에서 세대 u의 ESS 충전(방전) 전력량

: ESS charging (discharging) wattage of generation u at time t

: 세대 부하 공급을 위한 시간 t에서 세대의 ESS 유효 전력 방전량

: ESS active power discharge amount of household at time t for household load supply

: 그리드 공급을 위한 시간 t에서 가정의 ESS 유효 전력 방전량

: ESS active power discharge amount of the household at time t for grid supply

: 세대 부하 공급을 위한 시간 t에서 세대 u의 PV 유효 전력량

: PV active power amount of household u at time t for household load supply

: 그리드 공급을 위한 시간 t에서 세대 u의 PV 유효 전력량

: PV active wattage of generation u at time t for grid supply

: 시간 t에 선로 uv에서 유효(무효) 전력 흐름

: active (reactive) power flow in line uv at time t

: 시간 t에서 세대 u의 노드 유효(무효) 전력량

: Node active (reactive) power amount of generation u at time t

: 시간 t에서 세대 u의 제어 가능한 부하의 유효(무효) 전략 소비량

: effective (ineffective) strategy consumption of controllable load of generation u at time t

: 시간 t에서 세대 u의 내부 온도

: internal temperature of generation u at time t

: 시간 t에서 세대 u의 전력 거래 상태를 보장하기 위한 이진 변수

: Binary variable to guarantee the power transaction state of generation u at time t

: 시간 t에서 세대 u의 ESS 충전 및 방전을 만족시키기 위한 이진 변수

: Binary variables for satisfying ESS charging and discharging of generation u at time t

: 시간 t에서 세대 u의 PV 시스템으로부터 주입/흡수되는 무효 전력량

: amount of reactive power injected/absorbed from the PV plant of generation u at time t

: 시간 t 및 세대 u에서 3상에 대한 전압 크기의 제곱 벡터

: square vector of voltage magnitudes for three phases at time t and generation u

: 공칭전압(nominal voltage)에서 시간 t에서 세대 u의 유효(무효) 전력 소비량

: effective (reactive) power consumption of generation u at time t at nominal voltage

: 시간 t에서 각 위상에 대한 OLTC 턴 비율(turn ratios)의 제곱

: the square of the OLTC turn ratios for each phase at time t

: 시간 t에서 위상

의 OLTC의 적절한 턴 비율을 결정하기 위한 이진 변수

: phase at time t

Binary variable to determine the proper turn ratio of the OLTC of

: 시간 t에서 그리드로부터(또는 그리드에서) TOU-기반 판매(또는 구입) 가격

: TOU-based sale (or purchase) price from (or on grid) grid at time t

: 세대 u의 불편 비용에 대한 패널티 파라미터

: Penalty parameter for the inconvenience cost of generation u

: 시간 t에서 세대 u의 예측된 PV 유효 전력 출력

: predicted PV active power output of generation u at time t

: 세대 u의 ESS 충전(방전) 효율

: ESS charging (discharging) efficiency of generation u

: 세대 u의 최대 ESS 용량

: Maximum ESS capacity of generation u

: 시간 t에서 세대 u의 예측 외부 온도

: predicted external temperature of generation u at time t

: 세대 u의 최소(최대) ESS 충전 상태

: Minimum (maximum) ESS charge state of generation u

: 세대 u의 최소 ESS 충전 유효 전력

: Minimum ESS charging active power of generation u

: 세대 u의 최대 ESS 충전 유효 전력

: Maximum ESS charging active power of generation u

: 세대 u의 최소 ESS 방전 유효 전력

: Minimum ESS discharge active power of generation u

: 세대 u의 최대 ESS 방전 유효 전력

: Maximum ESS discharge active power of generation u

: 세대 u의 최소(최대) 내부 온도

: Minimum (maximum) internal temperature of generation u

: 세대 u의 최소(최대) 제어 가능한 부하 유효 전력 소비량

: Minimum (maximum) controllable load active power consumption of generation u

: 세대의 불편 비용의 최대 이완(relaxation) 변수

: Maximum relaxation variable of household discomfort cost

: 시간 t에서 세대 u의 최소(최대) 제어 불가능한 부하 유효 전력 소비량

: Minimum (maximum) uncontrollable load active power consumption of generation u at time t

: 위상

에서 세대 u의 최소(최대) PV 무효 전력 용량

: Phase

Minimum (maximum) PV reactive power capacity of generation u in

: 위상

에서 세대 u의 최소(최대) ESS 무효 전력 용량

: Phase

Minimum (maximum) ESS reactive power capacity of generation u in

: 시스템에서 전압 크기의 최소(최대)의 제곱

: the minimum (maximum) square of the voltage magnitude in the system

: 시스템에서 전압 크기 제곱의 공칭값

: the nominal value of the square of the voltage magnitude in the system

(여기서,

는 스케줄링 지평선의 셋이다)인 각 소비자(또는 세대)에 대해, 일반적인 HEMS 최적화 알고리즘은 다음과 같이 공식화된다. the scheduling period

(here,

For each consumer (or generation) that is the set of scheduling horizons, the general HEMS optimization algorithm is formulated as

Equation 1 of the objective function for the HEMS optimization problem consists of two parts.

The first part represents the total electricity cost for the scheduling period T, where T is set to 24 hours with a scheduling resolution of 1 hour.

)에 따른 세대의 순 유효 전력 소비량(

)과 TOU 기반 판매 가격(

)에 따른 순 전원 공급량(

)의 전기 구매 비용과 전기 판매 비용의 차이이다. The total electricity cost is the TOU-based purchase price (

) net active power consumption of households according to (

) and the TOU-based selling price (

) according to the net power supply (

) is the difference between the cost of purchasing electricity and the cost of selling electricity.

)은 총 패널티 비용(

)을 나타내며 이는 소비자의 불편 비용과 관련된다. second part (

) is the total penalty cost (

), which is related to the cost of inconvenience to consumers.

The inconvenience here is the difference between the temperature preferred by the consumer and the room temperature.

는 HEMS의 최적화 문제의 실행 가능성을 보장하기 위한 이완 변수이다.

is a relaxation variable to ensure the feasibility of the optimization problem of HEMS.

는

에 대한 패널티를 나타낸다.

Is

represents a penalty for

가 증가함에 따라

는 감소하고, 결과적으로 실내 온도와 소비자 선호 온도의 차이가 최소화되지만 하지만 전기료 절감 정도는 작아진다. E.g,

as the increases

decreases, and as a result, the difference between the indoor temperature and the consumer's preferred temperature is minimized, but the degree of electricity cost savings is small.

)에 따른 모든 가전 제품(

)의 총 유효 전력 소비량과 ESS 방전(

)에 따른 PV로부터의 총 유효 전력 공급량(

)과의 차이이다. Equation 2 is the net energy consumption, e.g., ESS charging in one generation (

All household appliances according to ( )

) of total active power consumption and ESS discharge (

Total active power supply from PV according to ( )

) is the difference from

)에 대한 제약이고, ESS의 방전 유효 전력(

)과 PV 시스템이 주입한 유효 전력(

)으로 구성된다. Equation 3 is the sales power of consumers (

), and the discharge active power of the ESS (

) and the active power injected by the PV plant (

) is composed of

) 생성량은 세대의 전력 소비량(

)과 그리드로 공급한 전력량(

)의 합으로 나타난다. In Equation 4, the predicted PV active power (

) is the generation's power consumption (

) and the amount of electricity supplied to the grid (

) as the sum of

)은 세대의 전력 소비량(

)과 그리드에 판매한 전력량(

)의 합으로 나타난다. In Equation 5, the total ESS discharge power (

) is the household's power consumption (

) and the amount of electricity sold to the grid (

) as the sum of

)에서 유효 전력 흐름은 소비자 v에서 노드 유효 전력(

)과 노드 v에서 노드 w로의 유효 전력 흐름의 합과 관련되고, 여기서 w는 노드 v에 연결된 일련의 다운스트림 노드

이다. The equilibrium equation for active power flow is Equation 6, where the branch uv(

) from the active power flow at the consumer v to the node active power (

) and the sum of the active power flows from node v to node w, where w is the set of downstream nodes connected to node v

am.

)은 수학식 7과 같이 순 전력 소비량과 그리드로의 순 전력 공급량과의 차이로 표현된다. Node active power (

) is expressed as the difference between the net power consumption and the net power supply to the grid as shown in Equation 7.

)이 제어 가능한 부하의 유효 전력 소비량(

)과 제어 불가능한 노드의 유효 전력 소비량(

)의 합이라는 점을 나타낸다. Equation 8 is the active power load consumption (

) is the active power consumption of this controllable load (

) and the active power consumption of uncontrollable nodes (

) is the sum of

), 충방전 효율(

,

) 및 소비자의 충방전 전력량(

,

)으로 표현된다는 점을 나타낸다. Equation 9 shows that the state of charge of the ESS at the current time t is the state of charge of the previous time (t-1), the battery capacity (

), charge/discharge efficiency (

,

) and the consumer's charge/discharge power (

,

) is expressed as

)의 제약이고, 이는 시간 t-1에서의

, 시간 t에서의 예측된 외부 온도(

), 에어컨의 전력 소비량(

) 및 외부 온도 조건에 관한 환경 파라미터(

)로 표현된다. Equation 10 is the temperature dynamics of the air conditioner at time t (

), which is at time t-1

, the predicted external temperature at time t (

), the power consumption of the air conditioner (

) and environmental parameters regarding external temperature conditions (

) is expressed as

Equations 11 and 12 ensure that the purchase and sale of power to or from the grid do not occur simultaneously.

Equation 13 provides the capacity constraint of the SOC for the ESS.

) 및 방전 전력(

)에 관한 제약을 나타내며, 여기서,

는 ESS의 충방전 상태를 결정하는 이진 변수를 나타낸다. Equations 14 and 15 are the charging power of the ESS (

) and discharge power (

) represents the constraint, where,

represents a binary variable that determines the charge/discharge state of the ESS.

는 수학식 17에서

에 의해 제한된다. Equation 16 represents the relaxation external temperature range. Relaxation variable in Equation 16

is in Equation 17

limited by

The power consumption capacity of the air conditioner is expressed in Equation (18).

), ii) 불균형 분배 피더 및 전압 의존 부하 모델, iii) 무효 전력 소비 가전 제품 및 iv) DER 및 OLTC를 통한 전압 조정과 같은 동작 조건을 무시한다. The existing HEMS approach mentioned above depends on the actual distribution system parameters, network topology, and i) line impedance (

), ii) unbalanced distribution feeders and voltage dependent load models, iii) reactive power consuming appliances, and iv) operating conditions such as voltage regulation via DER and OLTC.

Hereinafter, a HEMS optimization method for solving this problem will be described in detail.

)에서 구체화된다. The HEMS optimization algorithm according to this embodiment is a three-phase unbalanced distribution network (phase

) is specified in

In the HEMS algorithm according to the present embodiment, the remaining equations except for Equation 8 are expressed as follows.

는 시간 t에 그리드로부터 TOU 기반으로 구입하는 가격,

는 시간 t에서 위상

에 대한 세대 u의 순 유효 전력 소비량,

는 시간 t에 그리드로 TOU 기반으로 판매하는 가격,

는 시간 t에서 위상

에 대한 세대 u의 그리드 공급을 위한 순 유효 전력 소비량,

는 위상

에서 세대 u의 불편 비용에 대한 패널티 파라미터,

는 시간 t에서 위상

에 대한 세대 u의 불편 비용(discomfort cost)이다. here,

is the purchase price based on TOU from the grid at time t,

is the phase at time t

net active power consumption of generation u for

is the selling price based on TOU as a grid at time t,

is the phase at time t

net active power consumption for grid supply of generation u for

is the phase

a penalty parameter for the inconvenience cost of generation u,

is the phase at time t

is the discomfort cost of generation u for .

에 대한 세대 u의 순 무효 전력 소비량(

)을 무효 부하 전력 소비량(

) 및 PV 및 ESS로부터 주입 또는 흡수된 무효 전력(

,

)의 관점에서 표현한 것이다. Equation 20 is the phase at time t

net reactive power consumption of generation u for (

) to the reactive load power consumption (

) and reactive power injected or absorbed from PV and ESS (

,

) is expressed in terms of

)은 소비자의 노드 무효 전력(

)과 노드 v에서 노드 w로의 무효 전력 흐름의 합으로 표현된다. 여기서, w는 노드 v에 연결된 일련의 다운스트림

에 존재한다. 수학식 22에서 노드 무효 전력(

)은 순 무효 전력 소비량(

)와 같다. The equilibrium equation of the reactive power flow is shown in Equation 21, where the reactive power flow at branch uv (

) is the consumer's node reactive power (

) and the reactive power flow from node v to node w. where w is the set of downstream connections connected to node v

exists in In Equation 22, the node reactive power (

) is the net reactive power consumption (

) is the same as

) 및 유효 전력(

)의 관점으로 표현된다. As in Equation 23, the reactive power consumption of the air conditioner is its power factor (

) and active power (

) is expressed in terms of

,

및

로 표기한다. According to this embodiment, a complex vector and matrix of voltage, current, and line impedance are

,

and

marked with

와 함께 선형화 방법을 사용하여 세대 u와 v 사이의 전압 관계를 다음과 같이 쓸 수 있다.Kirchhoff's Voltage Law

Using the linearization method with , the voltage relationship between generations u and v can be written as

는 시간 t에서 세대 u의 3상 전압 크기의 제곱 벡터이고,

와

는 시간 t에서 선로 uv의 3상 유효 및 무효 선로 흐름이며,

이다. here,

is the square vector of the three-phase voltage magnitude of generation u at time t,

Wow

is the three-phase valid and reactive line flow of line uv at time t,

am.

는 요소별 곱셈(elementwise multiplication)이고,

는 다음과 같이 정의된다. here,

is elementwise multiplication,

is defined as

에 기초하여 본 실시예에 따른 시간 t에서 세대 u의 3상 유효 및 무효 부하에 대한 선형화된 전압 의존 모델은 다음과 같이 표현된다. Two variables of Kirchhoff's voltage law and McCormick Envelopes relaxation technique

Based on the linearized voltage dependence model for the three-phase active and reactive loads of the generation u at time t according to the present embodiment is expressed as follows.

는

에 대해,

로 표현되고,

와

는 일정한 임피던스, 일정한 전류 및 일정한 유효 및 무효 전력에 대한 전력 부하의 백분율을 나타내는 계수의 셋이며,

와

방정식을 만족시키며,

는 시간 t에서 세대 u의 3상 전압 크기의 제곱 벡터이다. here,

Is

About,

is expressed as

Wow

is a set of coefficients representing the percentage of power load to constant impedance, constant current and constant active and reactive power,

Wow

satisfies the equation,

is the square vector of the magnitude of the three-phase voltage of generation u at time t.

Equations 28 and 29 below represent the limits of nominal active and reactive load power consumption.

와

는 다음에 의해 경계가 정해진다. According to McCormick Envelopes relaxation, two variable vectors in Equations 26 and 27

Wow

is delimited by

,

)의 관점에서 다음과 같이 표현된다. At time t, the three-phase active and reactive load consumption at nominal voltage for generation u is equal to the active and reactive power consumption of the controllable appliance (

,

) is expressed as follows.

Equations 36 and 37 below represent capacity limits of reactive power supplied by the PV system and the ESS.

) 및 최대값(

)을 나타낸다. Equation 38 is the minimum value of the range of the voltage magnitude squared of generation u (

) and maximum (

) is indicated.

와 OLTC 탭 위치에 의해 결정되는 OLTC 턴 비율의 제곱

의 곱으로 표현된다. Equation 39 represents the square of the magnitude of the reference node voltage, which is the magnitude of the square of the nominal voltage.

and the square of the OLTC turn rate determined by the OLTC tap position

is expressed as the product of

의 제곱은 다음과 같이 유도된다. In Equation 39, the OLTC turn ratio

The square of is derived as

라 할때, 여기서,

는 OLTC의 턴 비율 셋

의 요소이고,

는 OLTC 턴 비율에 상응하는 탭 위치 셋이고,

는 상기한 셋에서 적절한 턴 비율을 결정하기 위해 사용된다.

When saying, here,

is the turn ratio of OLTC 3

is an element of

is the set of tap positions corresponding to the OLTC turn ratio,

is used to determine the appropriate turn ratio in the set above.

OLTC assumes that the voltage is regulated over a range of 10% of the nominal voltage, with each tap position 0.00625 p.u. Changed to turn ratio size.

및 이진 변수

라 하면, OLTC 턴 비율의 제곱은 다음과 같이 표현될 수 있다.

and binary variables

Then, the square of the OLTC turn ratio can be expressed as follows.

In the three-phase unbalanced low voltage distribution network according to the present embodiment, HEMS optimization may be performed in a computing device installed within a household or on a line connecting the households.

As shown in FIG. 2 , the optimization apparatus according to the present embodiment may include a processor 200 and a memory 202 .

The processor 200 may include a central processing unit (CPU) capable of executing a computer program or other virtual machines.

Memory 202 may include a non-volatile storage device such as a fixed hard drive or a removable storage device. The removable storage device may include a compact flash unit, a USB memory stick, and the like. The memory may also include volatile memory, such as various random access memories.

에 대한 목적함수를 구성하고, 상기 목적함수에 대해 무효 전력 제약 조건, 3상 선형 전압 제약 조건, 전압 의존 부하 모델, 태양광 발전(PV) 및 에너지 저장 시스템(ESS)의 무효 전력, 전압 및 부하 시 탭 절환기 중 적어도 하나를 고려하여 상기 수집된 전력 소비 데이터로부터 가전 제품의 부하 감소 및 부하 쉬프팅을 위한 최적화 해를 계산할 수 있다. According to an embodiment of the present invention, program instructions for a predetermined operation are stored in the memory 202, and the program instructions according to the present embodiment receive power from each of a plurality of households supplied with power from a three-phase unbalanced low voltage distribution network. Consumption data is collected and related to the total electricity cost and household inconvenience cost during the scheduling period for HMES optimization, and the phase at time t

Construct an objective function for , and reactive power constraint, three-phase linear voltage constraint, voltage-dependent load model, reactive power, voltage and load of photovoltaic (PV) and energy storage system (ESS) for the objective function An optimization solution for load reduction and load shifting of household appliances may be calculated from the collected power consumption data in consideration of at least one of the time tap changers.

The above-described embodiments of the present invention have been disclosed for the purpose of illustration, and various modifications, changes, and additions will be possible within the spirit and scope of the present invention by those skilled in the art having ordinary knowledge of the present invention, and such modifications, changes and additions should be regarded as belonging to the following claims.

Claims (5)

A home energy management system (HEMS) optimizer in a three-phase unbalanced low voltage distribution network, comprising:
processor; and
a memory coupled to the processor;
The memory is
collecting power consumption data from each of a plurality of households receiving power from the three-phase unbalanced low voltage distribution network;
For the HMES optimization, related to the total electricity cost and household inconvenience cost during the scheduling period, the phase at time t

construct an objective function for
Reactive power constraint, three-phase linear voltage constraint, voltage-dependent load model, reactive power of photovoltaic (PV) and energy storage system (ESS), voltage and on-load tap-changer are taken into account for the objective function. To calculate an optimization solution for load reduction and load shifting of household appliances from the obtained power consumption data,
store program instructions executed by the processor,
The voltage dependent load model is defined using the square vector of the three-phase voltage magnitude of generation u at time t, three-phase effective and reactive line flow and line impedance of line uv at time t,
The objective function is defined as follows for the scheduling period (T),
[Equation]

here,

is the purchase price based on TOU from the grid at time t,

is the phase at time t

net active power consumption of generation u for

is the selling price based on TOU as a grid at time t,

is the phase at time t

net active power consumption for grid supply of generation u for

is the phase

a penalty parameter for the inconvenience cost of generation u,

is the phase at time t

is the inconvenience cost of generation u for
Home energy management system optimizer considering the following linearized voltage dependence model for three-phase active and reactive loads of generation u at time t.
[Equation]

[Equation]

here,

Is

About,

is expressed as

Wow

is a set of coefficients representing the percentage of power load to constant impedance, constant current and constant active and reactive power,

Wow

satisfies the equation,

is the square vector of the magnitude of the three-phase voltage of generation u at time t delete delete delete A method for optimizing a home energy management system (HEMS) in a three-phase unbalanced low voltage distribution network performed in a device comprising a processor and a memory, the method comprising:
collecting power consumption data from each of a plurality of households receiving power from the three-phase unbalanced low voltage distribution network;
For the HMES optimization, related to the total electricity cost and household inconvenience cost during the scheduling period, the phase at time t

constructing an objective function for and
Reactive power constraint, three-phase linear voltage constraint, voltage dependent load model, reactive power of photovoltaic (PV) and energy storage system (ESS), voltage and on-load tap-changer are taken into account for the objective function. calculating an optimization solution for load reduction and load shifting of household appliances from the obtained power consumption data,
The voltage dependent load model is defined using the square vector of the three-phase voltage magnitude of generation u at time t, three-phase effective and reactive line flow and line impedance of line uv at time t,
The objective function is defined as follows for the scheduling period (T),
[Equation]

here,

is the purchase price based on TOU from the grid at time t,

is the phase at time t

net active power consumption of generation u for

is the selling price based on TOU as a grid at time t,

is the phase at time t

net active power consumption for grid supply of generation u for

is the phase

a penalty parameter for the inconvenience cost of generation u,

is the phase at time t

is the inconvenience cost of generation u for
Home energy management system optimization method considering the following linearized voltage dependence model for three-phase active and reactive loads of generation u at time t.
[Equation]

[Equation]

here,

Is

About,

is expressed as

Wow

is a set of coefficients representing the percentage of power load to constant impedance, constant current and constant active and reactive power,

Wow

satisfies the equation,

is the square vector of the magnitude of the three-phase voltage of generation u at time t

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