GTI的网格负载电源监控电路

The post explains a circuit idea which can be used as a power monitor and control system for ensuring that only the specified amount of watts is allowed to enter into the allocated socket, as per the maximum calculated wattage of the appliances connected across those points. The idea was requested by Mr. Bob Rudman.

Technical Specifications

I have solar panels on my roof that pump 3Kw into the grid in full sunlight, I don’t get the money for what goes’ into the grid, my landlord does, I only get the savings for the energy I use during the hours of daylight.

我想要的是一个电路来自动调整the power fed into my water heater or night storage heater that would be plugged into a wall socket to match that coming from the solar panels.

The way this would work would be to monitor the energy going into the grid on the mains cable coming into the house, and automatically adjust the power going into the appliance to bring this to a null point I.E. ( nothing coming in and nothing going out ).

我曾经拥有其中一个能量监测器，这些能量显示器显示了我使用的能量，但在太阳能电池板装配后必须停止使用它，因为它无法检测到电源上的电流流动的电流，所以这是在电路设计中需要考虑的东西。

希望你能提供帮助。

Best regards Bob Rudman

The Design

As far as I have understood, the application requires a system to monitor and allow a specified amount energy to enter the grid which may be equivalent to the intended load wattage rating in use.

The idea actually may be technically incorrect, and might not be feasible, because once the specified solar inverter energy is fed into the grid line, it becomes accessible to all who may be connected with the grid across the area.

然而，如果太阳能AC被馈送到栅极线，则可能靠近预期设备，那么在一定程度上可以根据负载规范来优化能量。

远处电平的其他负载可能无法通过在路径上提供的电线的相对较高的电阻而无法访问功率。

下图解释了如何实现概念：

电路操作

现在，这个想法看起来很简单，这里的Opamp被配置为比较器。

最初，TRIAC MT1 / MT2点暂时短路，从太阳能逆变器的输入电源接通。

指定的负载范围在应用此AC的网格点上连接。

The above action develops a certain predetermined level of potential across Rx which becomes just sufficient for triggering the associated BC547 transistor.

The transistor grounds the pin#2 of the IC via the 10K resistor producing a certain level of potential difference at pin#2.

After this, the pin#3 preset is adjusted so that the red LED just lights up, which indicates pin#6 is rendered high and the connected BC547 is now switched ON.

This in turn makes sure that at this point the triac is switched OFF, however it does effect the situation since we have the triac points shorted and the circuit is in the setting up phase.

The procedures sets up the circuit so that now the power is switched OFF and the short across the triac is removed.

一旦连接的负载量超过指定限制，电路现在完全设置用于响应和切断三端双向可控硅，这是TRIAC被迫关闭，以关闭负载的开关（用于一秒钟的一小部分），直到情况在Opamp输入引脚上校正使三端双向可控硅转换接通，并且情况以快速速率保持切换，确保电网仅由用户设置提供预定的固定电量量。

Rx may be set as per the following formula:

Rx = 0.6 /最大预期网格瓦数

The triac current rating may be selected as per the load wattage specifications.