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Purpose. Improving the principles of management of photovoltaic system with storage battery and with autonomous functioning during daylight hours for a local object, connected to the grid with multi-zone payment when excluding the generation of energy into the grid. Methodology. Modeling and analysis of energy processes in the photovoltaic system was performed using the Matlab software package. The simulation model of energy processes is based on calculated expressions taking into account the characteristics of the battery. Operability of the proposed solutions are confirmed on an experimental setup based on a standard hybrid inverter. Results. It’s shown, that due to the battery energy during the most loaded peak hours and part of the daytime the system operates autonomously and does not depend on possible violations of the quality of electricity in the grid. Scenarios of the recommended load schedule are proposed in accordance with the ratio of the predicted value of the daily energy generation of the photovoltaic battery to its possible maximum value. A simulation model of energy processes in the system with the correction of the recommended load value was developed. Originality. A method of the recommended load calculation with current correction for the actual generation and degree of battery charge is proposed, which allows taking into account differences the actual generation of the photovoltaic battery from its predicted value and the actual load from the recommended one. Practical value. The obtained solutions are the basis for the design of new and modernization of existing photovoltaic systems of local objects using software and hardware complexes for power consumption management.

The use of a grid-tied photovoltaic system with a storage battery to increase the power of objects of railway transport infrastructure above the limit on consumption from the grid with the possibility of energy saving is considered. The methods of analysis of energy processes in photovoltaic systems with a storage battery are used. They are added via the processing of archival data of power generation of a photovoltaic battery and computer modeling results. A technique of system parameter calculation to increase the power according to the given load schedule of the object at constant and maximum possible degree of power increasing is developed. The values of the average monthly generation of a photovoltaic battery at the location point of the object based on archival data are used. The principle of the control of power, consumed from the grid, according to the given values of the added and total load is developed. Using the basic schedule of added load power in connection with the graph of photovoltaic battery generation allows reducing the installed power of the storage battery. The additional reduction in the installed power of the photovoltaic and storage batteries is possible at the corresponding choice of the degree of power load increasing. The joint formation of current schedules with reference to the added power value and state of charge of the battery according to the short-term forecast of the generation of a photovoltaic battery is proposed. The value of added power at certain intervals of time is set according to the graph of actual generation of the photovoltaic battery, which contributes to the maximum use of its energy. With the average monthly generation of a photovoltaic battery in the spring–autumn period, the discharge of the battery during the hours of the morning load peak is not used. This reduces the number of deep discharge cycles and extends the battery life. The description of energy processes in steady-state conditions for the daily cycle of system functioning is formalized. On this basis, a mathematical model is developed in MATLAB with an estimation of the costs of electricity consumed from the grid. When modeling, archival data are used for days when the generation of a photovoltaic battery over time intervals is close to average monthly values. This makes it possible to evaluate the effectiveness of system management under conditions close to real during the year.

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This work aimed to improve how the equipment of a grid-tied solar-wind system used the installed power of the storage battery while reducing the cost of electricity consumed by a local object from the grid. A method for calculating the parameters for a given load schedule is proposed, along with the value of the reduction in electricity consumption. Values for the power generation of a wind generator and photovoltaic battery are based on archival data. The possible power ratio of the wind generator and the photovoltaic battery is 1:8.33. The formation of the state of charge of the battery involves: a calculation of its value for the morning peak according to the forecast for the next day; adjustable discharge in the evening with full or partial compensation for the load consumption according to the forecast for the next day; a night charge with a given current value. At a one-tariff plan, one battery discharge cycle per day is used. A night charge from the grid is not used. With a two-tariff plan and the use of a night battery charge from the grid, one discharge cycle is used in the spring-summer-autumn period. The simulation confirms the possibility of reducing electricity costs by 2.9 times in winter, which corresponds to the set value, alongside a complete elimination of costs in summer.