JPS59207565A - Control system of air cooling fuel cell - Google Patents

Abstract

PURPOSE:To keep cell operation temperature constant by detecting a load, each temperature in air supply and exhaust, and air flow rate during cell operation and calculating them with a controller based on a specified program to control a blower and a damper. CONSTITUTION:Air necessary for reaction and cooling of a fuel cell is supplied to a stack S with a blower 7 through a manifold 8. Exhaust air from a manifold 8' is exhausted through a damper 3. Air flow rate is detected with an air flow rate detector 14, temperature is with temperature detectors 11 and 12 installed in manifolds 8 and 8', and load current is with a detector 4. Detected signals are inputted into a controller 13 and calculated based on a specified program, and the blower 7 and damper 3 are controlled by an output from the controller. Operation temperature of a cell is kept almost constant regardless of load variation, and reliability is increased without installing the temperature detectors 11 and 12 within the stack S.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a control method for an air-cooled fuel cell.

(B) Prior Art Conventional battery temperature control involves embedding a temperature detector (1) inside the battery as shown in Figure 1, and transmitting the temperature detected by the temperature detector (2) to a damper (3). ) and
This was done by controlling the temperature of the supplied air. At the same time, the load current is detected by a detector (4) such as a transformer, and the rotation speed of the blower (7) is adjusted to 1" by the inverter (6) via the controller (5) to match the load. It was controlled by the wind.

However, in order to embed the temperature sensor f1+ inside the battery, 1
) In order to insert the detection part into the force distribution groove of the gas separation plate, it is necessary to use an extremely thin one, which has poor mechanical strength and may break. 11) It is dangerous because it is in direct contact with the electrode, so it can be damaged by corrosion due to acid and cause an electrical short circuit.11
1) There is a possibility of damaging the electrode, and there are problems in that the reaction area is reduced due to the buried portion. Further, in the first system, there is no correlation between the adjustment of the proar and the damper, and there is a drawback that appropriate control according to the load cannot be performed.

(C) Purpose of light/j The purpose of the present invention is l (1) to solve the problems caused by embedding the temperature detector in the battery as described in j, and to make it possible to monitor the battery operating temperature regardless of load fluctuations. The goal is to control the temperature so that it remains constant.

2) The invention originated by Rei Umenari] detects the load amount, air supply and exhaust temperature, and air flow rate during battery operation, calculates it with a controller based on a predetermined program, and changes the load based on the calculated output signal. The present invention is characterized in that the air flow rate and air supply temperature are controlled by adjusting a blower and a damper so that the battery operating temperature is kept substantially constant regardless of the temperature.

(Embodiment) An embodiment of the present invention will be explained with reference to FIG. 2, and the corresponding parts are given the same symbols as in FIG. 1.

An air supply and discharge manifold (8H8) and a fuel gas (hydrogen) supply and discharge manifold (9 bars 91) are attached to each side of the stack (S) so as to face each other.

The air necessary for the reaction and cooling of the battery is blocked by the blower (7) via the manifold (8) to the stack (S), and a portion of the air exhausted from the manifold (81) is directed outside by the damper (3). At the same time as it is discharged, the remaining 'r(s) is sent to the circulation path (
1 (1), and is supplied to the stack (S) together with fresh air that can be introduced in proportion to the exhaust air.Meanwhile, fuel power is supplied from the manifold (9) and passes through the stack (S) to the manifold (9)1. more excreted.

The temperature detector (n)Oz+ according to the present invention is installed near the supply port and the discharge port in the air manifold fg)isr, respectively, and these detection signals (TI) (T2) are sent to the calculation control unit θ.
3) is input.

The air flow rate detector (14) detects the air differential pressure using a pitot tube, etc., and converts this into an electric signal using a pneumatic converter (+51) and inputs it to the controller (I (8)). Similarly, it is detected by a detector (4) such as a transformer and input to the controller a1 (03).

These input signals for air supply, discharge side temperature, air flow rate, and load amount are calculated by the controller (13) based on a predetermined program, and are used as output signals to control the blower (7) and gun bar (3). . The details will be explained below 2. Generally speaking, the heat generation amount (Ql) of a battery is related to the load as a relational expression: Q1=C11CVo-V)kwh...=-...(1)
Here, C1: Coefficient, I: Negative turtle flow VO: Dynamic electromotive force V: Operating chamber pressure, and the air pressure (Q2) is Q22C.
2yC'12-T'l) kcal ・-・-(
2! This is increased by hfi (:2: coefficient, v: air flow rate), l: air supply Ia temperature, T2: air discharge temperature.

Battery calorific value (Ql) and air cooling i=, (Q2
) are equal, so the formula (ll(2i y C, I I (V
OV)=C227-(T2-TI)a...
Old (31) Since the units are different from Qlkw and h Q2: 1 ccal, 1 kwh = 860 kcal Q
1 = Q 2/860, and the relational expression where α is the final value holds true.

In equation (3), 1. V,bi,'f2. 'f1 is a variable related to actual battery operation, among which 1. V is electric A
Jl is determined directly by the load, and Tl is controlled based on the load. Note that T2 is a variable related to T1 and the battery load (generation 8).

Next, the actual control operation will be explained.

If the load moves while the battery is operating under certain conditions, this is detected by the load current detector (4), and the inverter (6) is adjusted by the controller (13) based on the result. , the amount of air to be supplied according to the load is checked by the detector H and then set. For example, 60 m for 100 A/c
/H, 80A 50 m” for /crrf, /H
Do like this.

At the same time, the supply air temperature (T1) and the exhaust air temperature (T2) to the battery stack (S) are measured by the respective temperature detectors (river (1)
2], the controller θ3) calculates based on the above equation (3), adjusts the sidamba (3) according to the relationship between the air flow rate (+/) and the load (V, I), and then adjusts the battery stack (S). ) to keep the air supply temperature (T1) to an appropriate value.
In this control method, the air flow rate (1/) and air supply temperature (T1) are controlled so that the amount of heat generated by the battery (Ql) and the amount of cooling by air (Q2) are equal, and the battery operates regardless of load fluctuations. The temperature is kept approximately constant.

The relationship between electric and oil temperatures and T1 can be programmed in advance as described above, depending on the load amount, air flow rate, etc.
In addition, the discharge side temperature sensor θ2) is used to detect the difference between T2 and T1.It is fine if the difference between T2-'l"l is within the optimum temperature range, but the temperature difference changes widely. If this occurs, it has a function to apply feedback to readjust the proar (7) and damper (3) to maintain the temperature within the optimum range.

(F) Effects of the Invention According to the present invention, the battery temperature sensor is not embedded in the battery stack as in the past, but is installed in the supply and discharge ports of the air manifold, so it is possible to use the electrodes and the electrolyte. Since it does not come into contact with the load, it is possible to use a device with high mechanical strength without fear of damage, and the response to load fluctuations is improved, allowing accurate control.

In particular, in response to load fluctuations during battery operation, the load amount, air supply, exhaust temperature, and air flow rate are detected, and the controller calculates them based on a predetermined program to adjust the air flow rate.
Since the blower and damper are used to control the air supply temperature to an appropriate value, it is possible to maintain the battery operating temperature at a nearly constant level regardless of load fluctuations, which improves battery life. It contributes to

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing a conventional control device for an air-cooled fuel cell, and FIG. 2 is a system diagram of a control device according to the present invention. (S)...Battery stack (3)...Damper (4
)...Load current detector (6)...Inverter (
7)...Blower (8) (8)...Air supply and discharge side number manifold (II) (12i...Air supply and discharge side number temperature sensor θ3)...Calculation m1j waste unit f ``I...Air flow rate detector. Agent: Patent attorney: Yasuo Sano 1-.1.'□''i'
,j. 1・−2r°, Pa・,−′

Claims (2)

[Claims] (1) Equipped with a blower that adjusts the amount of air supplied to the battery, and a damper that adjusts the amount of air intake by changing the air discharge and circulation ratio.
Each temperature and air flow rate are detected extensively, and the controller calculates them based on a predetermined program. Based on the calculated output, the air flow rate is set by the proa according to the load, and the air supply temperature is set to an appropriate value. A control method for an air-cooled fuel cell characterized by controlling a damper to maintain a substantially constant cell operating temperature regardless of load fluctuations. (2) The air-cooled fuel cell according to item 1 of the scope of patent 8h, characterized in that the air supply and exhaust temperatures are detected by temperature detectors installed near the supply port and the discharge port of the manifold, respectively. control method.