JPS5856001A - N:1 backup system for decentralized microcontroller power source - Google Patents

Abstract

PURPOSE:To relieve a burden on an operator greatly when a power source is faulty, by monitoring the number of normal power sources and stopping the arithmetic of a controller in case of the fault of the power source in accordance with priority. CONSTITUTION:For example, if one of five power sources has a fault, the arithmetic of only a local controller SLC-4 with low priority is stopped to reduce the current consumption of the system. Then, a transmission controller SLC-5, a device master controller MC, a fuel system controller SLC-1, an air system controller SLC-2, and a water feed system controller SLC-3 which control a control system with high priority are allowed to perform arithmetic continuously. Thus, the number of normal power sources is monitored to allow the controllers to perform control, and as the number of faulty power sources increases, the arithmetic is stopped starting at the controller with the lowest priority. Consequently, automatic control by the controllers is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a distributed microcontroller power supply N:1 backup system, which controls a control system with a high priority when one power supply fails, then two power supplies fail in that order. The present invention relates to an N:1 backup method that enables automatic control of controllers.

° In the N:1 backup method of conventional distributed microcontroller power supplies, the number of power supplies is determined by the current consumption of the controller, and if two or more power supplies fail, all controllers will stop computing. For,
Automatic control by a controller was impossible. For this reason, all control systems that were previously controlled by individual controllers are switched to manual operation, so all controls must be performed manually, making operation difficult and requiring skill. there were.

An object of the present invention is to use an N:1 backup system for the power supply of a distributed microcontroller, so that even if two or more power supplies fail, all controllers do not switch to manual mode, and the control system with the highest priority is It is an object of the present invention to provide a control device that can reduce the burden on an operator and improve reliability when the power is cut off by continuing automatic control by a controller.

In the conventional N:1 backup method of distributed microcontroller power supplies, if two or more power supplies fail, all controllers stop operating. In the present invention, as one or two power supplies fail, the controllers that control the control system with the lowest priority stop calculations in order, reducing the consumption of the entire controller. The control system enables automatic control by a controller.

The overall configuration and operation of the present invention will be explained below with reference to FIGS. 1 to 3. FIG. 1 shows an example of a plant integrated control device in a thermal power plant.

The overall configuration is the same as the conventional N:1 backup method,
In the case of FIG.
It consists of A switching section T. This 4:1 backup method is
As shown in FIG. 2, the controller with a higher priority determines the number of power supplies in consideration of current consumption so that automatic control can be performed no matter how many of the five power supplies fail. In this system, conventionally, if two or more power supplies failed, it became impossible to supply drive current to all controllers, all controllers were stopped, and the H/A switching section was switched to slave operation. In the system of the present invention, as shown in Fig. 3, each controller monitors how many power supplies are normal, and it is possible to determine which controller to operate based on the number of normal power supplies in an interlock manner. , the controller priorities are determined.

That is, the priorities of the microcontrollers are determined as follows.

(1) Transmission controller (SLC-5) (2)
Unit mask controller (MC) (3) Fuel system controller (8LC-1) (4) Air system controller (SLC-2) (5) Water supply system controller (SLC-3)
) (6) Local control system controller (8LC-4
) Among the controllers, the local control system controller 5LC-4 controls NOx control,
Since this control, such as temperature control, has a relatively small influence on plant operation, and it is not very difficult to perform manual operation, this controller is given a low priority.

In other words, when all five power supplies are operating normally and the number of normal power supplies is four or less, the local control controller 5
Set up an interlock to stop the LC-4. This is because, as shown in Figure 2, when the power of the first unit goes down, the current consumption of all controllers can be secured, but when the power of the second unit goes down, the local control system controller 5LC-4 Before it stops, the current consumption drops below the amount required to drive all controllers, albeit instantaneously. As a result, all controllers temporarily stop, and the entire control system instantly switches to manual mode. In order to eliminate this problem, when one power supply goes down, if you stop the local control system controller 5LC-4, which has little effect on plant operation even with this manual operation, even if two power supplies go down, the remaining controllers Since the current consumption necessary to drive the controllers is secured, all controllers will not stop even temporarily. In other words, no matter how many controllers are powered down, the number of controllers that are still operating is always N:
1 backup is being performed.

Similarly, water supply system 5LC-3, air system controller 5LC
-2: If four or more out of five power supplies are operating normally, and three or less power supplies are operating normally, an interlock is set up to stop the controller. By monitoring the number of normal power supplies in this way, as the number of failed power supplies increases, if the calculations are stopped in order from the controllers with the lowest priority, important control systems can be automatically controlled by the controller even if the number of power supplies decreases. control becomes possible, greatly reducing the burden on operators in the event of a power outage.

According to the invention, N of the distributed microcontroller power supply
:1 When two or more power supplies fail in the backup method, all controllers stop and the control system does not switch to manual mode, and important control systems can be controlled by the controller, allowing operation even when the power is cut off. At the same time, the reliability of the control device itself is improved while reducing the amount of operation required by the operator.

[Brief explanation of the drawing]

Figure 1 is a system configuration diagram of a control device using a distributed microcontroller, Figure 2 is a diagram showing the relationship between the number of controllers that make up the system and the number of power supplies depending on the controller's current consumption, and Figure 3 shows how FIG. 4 is an interlock circuit diagram for determining whether to operate the controller. MC...Mask controller, SLC...Safloop controller, H/A...Han)', , t-cut L T (5 filled tt5!L,) Fast 3 Figure (θ (2)

Claims (1)

[Claims] 1. In the N:1 backup method of the power supply for distributed microcontrollers, if the power supply fails, only the controller that controls the control system with a lower priority will stop operating, thereby reducing system current consumption and increasing the priority A controller of a control system that controls a control system with a high level of power continues calculation and monitors the number of normal power supplies so that control by the controller is possible. An N:1/< pull-up method for a distributed microcontroller power supply characterized by stopping according to priority.