JPH0658693A - Control system of heat storage tank for cogeneration system - Google Patents

Abstract

PURPOSE:To contrive backup of a heat source apparatus group and an arbitrary heat power ratio by simply controlling a system having an engine-driven cogeneration system, a heat pump and a heat storage tank. CONSTITUTION:A heat load side QL and a heat source apparatus group thermal output side are formed through a heat storage tank ST, and as a heat source apparatus, a cogeneration system CGS and a heat pump H are disposed in parallel. When a heat power ratio is small, the cogeneration system is operated by following up an electric power, excess heat QST1 is stored in the tank ST, and when the ratio is large, part of heat demand is furnished by utilizing heat of the tank ST, and the residual heat demand is so provided by the system CGS and the pump H as to satisfy necessary and sufficient heat power ratio for the residual heat load and power load.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a heat storage tank in a combined heat and power supply system that combines an engine driven cogeneration system, a heat pump and a heat storage tank.

[0002]

2. Description of the Related Art FIG. 3 shows, for example, "cogeneration".
(Vol. 4, No. 2, 1989, P25 to P30) is a system diagram showing the optimum operation of the heat storage tank in the conventional cogeneration system shown in the figure, in which DG is a diesel engine generator and RE is an electric turbo. Refrigerator, RW is hot water absorption refrigerator, BA is hot water boiler, R
A is an oil-fired air conditioner, PC, PD, PH, PT, PW are various pumps, CT is a cooling tower, and ST is a heat storage tank.

Next, the operation will be described. The chain double-dashed line shows the flow of fuel, and the heavy oil A is the diesel engine generator DG.
And the hot water boiler BA and the oil-fired air conditioner RA.
Electric power is generated by the diesel engine generator DG, and exhaust heat is recovered and stored in the heat storage tank ST. The hot water in the heat storage tank is used to obtain cold water by the hot water absorption refrigerator RW to meet the cooling demand.

Further, the hot water in the heat storage tank ST is used for heating and hot water supply. If there is still excess, excess heat is discarded in the cooling tower CT. When the demand for heating and the demand for hot water supply cannot be met, the oil is supplied from the oil-cooling machine RA and the hot water boiler BA. Furthermore, to meet the demand for cooling, the oil-fired air conditioner RA
And the electric turbo refrigerator RE.

[0005]

Since the conventional method of operating the heat storage tank in the cogeneration system is configured as described above, it does not function as a connection between the load side and the heat source side. , There can only be a buffer function of the cogeneration system,
It has the disadvantage that it does not contribute to the selection of heat source units including other heat source units, and because it does not take into consideration the backup system in case of a failure, it has the problem of complicated control and poor reliability. It was

The present invention has been made to solve the above-mentioned problems, and a heat storage tank is arranged between the load side and the heat source side to serve as a joint between the both sides, and the heat source machine group as a whole. An object of the present invention is to provide a method of controlling a heat storage tank in a combined heat and power supply system that can perform capacity control and can meet the demand on the load side with simple control such as selection of a heat source model and backup at the time of failure.

[0007]

A method of controlling a heat storage tank in a combined heat and power supply system according to the present invention relates to a heat source unit and a heat load in which an engine driven cogeneration system and a heat pump are arranged in parallel via a heat storage tank. Separated,
When the power generation ratio on the heat load side is small relative to the thermoelectric generation ratio in the cogeneration system, the cogeneration system is operated according to the power demand, excess heat is stored in the heat storage tank, and conversely the power generation ratio on the heat load side. Is large,
A part of the required demand is radiated from the heat storage tank, and the remaining thermoelectric demand is driven by the power of the cogeneration system operated at the point where the thermoelectric generation straight line intersects the thermoelectric generation straight line in the thermoelectric generation diagram of the cogeneration system. The amount of heat from the heat pump is radiated through the heat storage tank on the heat load side.

[0008]

In the heat storage tank control method according to the present invention, excess heat is stored in the heat storage tank during power load follow-up operation when the thermoelectric load ratio is small, and when the thermoelectric load ratio is large, heat in the heat storage tank is stored. The control method has good controllability and is capable of satisfying an arbitrary demand for thermoelectric load while using the control method.

[0009]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to the drawings. In Figure 1, CGS engine driven cogeneration system, H is the heat pump, W _L is the power load, Q _L is the thermal load, ST is the heat storage tank, theta _ST heat storage tank temperature _{level, P C, P H, P} L Are pump, V _C and V respectively
_H and V _L are three-way valves, and W _A is auxiliary machine power.

FIG. 2 is a thermoelectric generation diagram of the engine-driven cogeneration system, where the horizontal axis Q _h is the heat generation amount, the vertical axis W is the power generation amount, a is the thermoelectric generation line, and X ₁ and X ₂ are the thermoelectric load demands. The points, Y ₁ and Y ₂ ', indicate the respective operating points of the cogeneration system. Q _ST1 indicates that the generated heat is excessive, and Q _ST2 indicates the amount collected from the generated heat.

As shown in FIG. 1, through the heat storage tank ST,
Configured by separated into the heat load Q _L side and the heat source unit group side.
In the heat storage tank ST, the left end is a high temperature tank and the right end is a low temperature tank. The heat load Q _L side constant flow rate pump P _L
Any hot water can be produced through the three-way valve V _L. On the heat source side, a cogeneration system CGS and a heat pump H are connected in parallel, constant flow rate pumps P _C and P _H are connected via three-way valves V _C and V _H , respectively, and the outlet water temperature is a constant high temperature. Is controlled to be.

With respect to the demand for X ₁ having a small thermoelectric load ratio in FIG. 2, the cogeneration system CGS operates at Y ₁ which follows the electric load, and the surplus heat Q _ST1 is stored in the heat storage tank ST. On the other hand, when X ₂ = Q _L / W _L , where the thermoelectric load ratio is large, part of the heat load Q _ST2 is covered by heat dissipation from the heat storage tank, so the deemed heat demand required for the cogeneration system is Q ′. _h, and the thermoelectric demand points required X _'1
Becomes ₂ cogeneration system C 'intersection Y of the heat demand realization line l and the thermoelectric generating lines a through _2, the slope of the 1 / (cop) (heat pump coefficient of performance)' thermoelectric demand point X
This is the operating point of the GS, and the electric power to the heat pump H at that time may be ΔW.

[0013]

As described above, according to the present invention, the load side and the heat source unit group side in which the cogeneration system and the heat pump are arranged in parallel are configured as a system via a heat storage tank, and the thermoelectric ratio is When the power is small, the power following operation is executed, excess heat is stored in the heat storage tank, when the thermoelectric ratio is large, part of the heat is used from the heat storage tank, and for the remaining heat, the cogeneration system and heat pump are used. Since the operation is necessary and sufficient for the heat load and the power load, it is possible to handle any power load and any heat load, and the backup of the heat source machine side can be automatically executed, which has the effect of simplifying control. .

[Brief description of drawings]

FIG. 1 is a configuration diagram of a heat generation tank of a cogeneration system and a heat pump according to an embodiment of the present invention.

FIG. 2 is a thermoelectric generation diagram of an engine-driven cogeneration system.

FIG. 3 is a system configuration diagram including a heat storage tank in a conventional cogeneration system.

[Explanation of symbols]

CGS engine driven cogeneration system ST storage tank H heat pump cop COP W _L power load (power demand) Q _L heat load X _1, X ₂ thermoelectric (load) demand point Y _1, Y ₂ 'cogeneration operating point Q _ST1 use heat Q _'h regarded heat demand l thermoelectric demand realized line a thermoelectric generation straight line from excess heat Q _ST2 storage tank

Claims (1)

[Claims] 1. A heat source machine comprising an engine-driven cogeneration system and a heat pump arranged in parallel and a heat load are separated via a heat storage tank, and the heat load side of the heat generation side with respect to the thermoelectric generation ratio in the cogeneration system. When the power generation ratio is small, the cogeneration system is operated according to the power demand, surplus heat is stored in the heat storage tank, and conversely when the heat load side power generation ratio is large, part of the required demand is radiated from the heat storage tank. However, the remaining thermoelectric demand is the amount of heat from the driven heat pump that receives the electric power of the cogeneration system operated at the intersection of the thermoelectric generation line and the thermoelectric generation line in the thermoelectric generation diagram of the cogeneration system. A method for controlling a heat storage tank in a combined heat and power supply system, characterized by radiating heat to a heat load side.