C#在工控行业的常见应用及代码示例

工业控制系统 (ICS) 正加速向数字化、智能化转型，C# 凭借其强大的框架支持、高效的开发能力和完善的生态，已成为工控软件的主流开发语言。本文将深入探讨 C# 在工控领域的典型应用场景并提供可直接落地的代码示例（基于 .NET 6+）。

一、工控系统核心应用场景

1. ​​PLC 通信与控制​​

​​协议支持​​： OPC UA、Modbus TCP、Siemens S7

// 使用 S7.Net 库控制西门子 PLC
public void ControlPlcValve(string ip, int dbAddress, int valveIndex, bool open)
{
    using var plc = new Plc(CpuType.S71500, ip, 0, 1);
    plc.Open();
    
    if (open)
        plc.Write($"DB{dbAddress}.DBX{valveIndex}", 1);  // 打开阀门
    else
        plc.Write($"DB{dbAddress}.DBX{valveIndex}", 0);  // 关闭阀门

    plc.Close();
}

// 读取设备状态
public (bool Running, int Temp) ReadEquipmentStatus()
{
    using var plc = new Plc(CpuType.S71200, "192.168.1.10");
    plc.Open();
    
    var running = plc.Read("DB1.DBX0.0");      // 运行状态
    var temp = plc.Read("DB1.DBW2");           // 温度值
    
    return (Convert.ToBoolean(running), Convert.ToInt32(temp));
}

2. ​​工业物联网 (IIoT) 数据采集​

// 使用 OPC UA 采集传感器数据
async Task<List<SensorData>> CollectOpcDataAsync()
{
    var results = new List<SensorData>();
    var endpoint = "opc.tcp://192.168.2.100:4840";

    using var client = new Client(new ApplicationConfiguration {
        ApplicationUri = "urn:localhost:OPCSample"
    });
    
    await client.ConnectAsync(endpoint);
    
    // 读取多个传感器节点
    var nodes = new[] {
        "ns=2;s=PressureSensor1",
        "ns=2;s=TemperatureSensor1",
        "ns=2;s=FlowRateSensor1"
    };
    
    var response = await client.ReadNodesAsync(nodes);
    
    foreach (var item in response)
        results.Add(new SensorData(item.Tag, item.Value, DateTime.UtcNow));
    
    return results;
}

3. ​​HMI（人机界面）开发​​

​​技术栈​​： WPF (MVVM模式) + OPC/Modbus 驱动

<!-- 设备状态监控界面 -->
<StackPanel Orientation="Horizontal">
    <led:RoundLed Width="30" Height="30" 
                  State="{Binding IsMotorRunning}" 
                  OnColor="Lime" OffColor="Red"/>
    <TextBlock Text="{Binding MotorSpeed}" Margin="10,0" 
               Foreground="{Binding SpeedAlert, Converter={StaticResource AlertColorConverter}}"/>
    <ProgressBar Value="{Binding Pressure}" Maximum="100" Width="150"/>
</StackPanel>

// MVVM 数据绑定实现
public class EquipmentViewModel : INotifyPropertyChanged
{
    private readonly OpcClient _opc;
    private Timer _updateTimer;
    
    public EquipmentViewModel()
    {
        _opc = new OpcClient();
        _updateTimer = new Timer(UpdateData, null, 0, 500);  // 500ms 刷新
    }
    
    private bool _isRunning;
    public bool IsMotorRunning
    {
        get => _isRunning;
        set => SetField(ref _isRunning, value);
    }
    
    private async void UpdateData(object state)
    {
        // 从 PLC 读取实时数据
        var status = await _opc.ReadValueAsync("Motor.Status");
        IsMotorRunning = Convert.ToInt32(status) == 1;
    }
}

二、关键开发技术栈

1. ​​工业通信协议库​​

​​协议​​	​​推荐库​​	​​特点​​
Modbus TCP	NModbus4	支持主/从站模式，异步API
OPC UA	Opc.Ua.Client	官方标准库，完善的安全机制
Ethernet/IP	InEther.Net	高性能 CIP 协议实现
MQTT	MQTTnet	轻量级 IIoT 通信首选

2. ​​实时数据存储方案​

// 时序数据库 InfluxDB 集成
async Task SaveToInflux(IEnumerable<SensorData> data)
{
    using var client = new InfluxDBClient("http://localhost:8086", "token");
    var writeApi = client.GetWriteApiAsync();
    
    var points = data.Select(d => PointData
        .Measurement("sensor_data")
        .Tag("sensor_id", d.SensorId)
        .Field("value", d.Value)
        .Timestamp(d.Timestamp, WritePrecision.Ns)
    );
    
    await writeApi.WritePointsAsync("factory_db", "autogen", points);
}

// 实时查询最近温度
async Task<double> GetLatestTemperature(string sensorId)
{
    var query = $@"from(bucket: ""factory_db"")
        |> range(start: -1h)
        |> filter(fn: (r) => r._measurement == ""sensor_data"")
        |> filter(fn: (r) => r.sensor_id == ""{sensorId}"")
        |> last()";
    
    var result = await _influx.QueryAsync(query);
    return result.First().GetValue<double>();
}

三、工控系统安全编程

1. 通信安全加固

// OPC UA 加密连接配置
var config = new ApplicationConfiguration {
    SecurityConfiguration = new SecurityConfiguration {
        ApplicationCertificate = new CertificateIdentifier {
            StoreType = "X509Store",
            StorePath = @"CurrentUser\My",
            SubjectName = "CN=PLCClient"
        },
        TrustedPeerCertificates = new CertificateTrustList {
            StoreType = "Directory",
            StorePath = @"C:\Certs\Trusted"
        },
        AutoAcceptUntrustedCertificates = false  // 生产环境必须关闭!
    },
    TransportQuotas = new TransportQuotas {
        OperationTimeout = 10000
    }
};

2. 操作权限控制

// 基于角色的控制指令验证
[Authorize(Roles = "Engineer, Admin")]
public async Task<IActionResult> StartEquipment(int equipmentId)
{
    // 获取当前用户
    var user = HttpContext.User;
    if (!user.HasClaim(c => c.Type == "FactoryArea"))
        return Forbid();
    
    var area = user.FindFirstValue("FactoryArea");
    if (!_equipmentService.IsInArea(equipmentId, area))
        return BadRequest("无权操作该区域设备");
    
    await _plcService.SendCommand(equipmentId, CommandType.Start);
    return Ok();
}

四、故障处理与监控

1. 异常状态诊断

// PLC 通信异常重试策略
async Task<object> ReadPlcWithRetry(string address, int maxRetries = 3)
{
    int attempt = 0;
    while (true)
    {
        try
        {
            return await _plc.ReadAsync(address);
        }
        catch (PlcException ex) when (ex.ErrorCode == ErrorCode.ConnectionError)
        {
            if (++attempt >= maxRetries) 
                throw new CriticalException($"PLC连接失败: {address}");
            
            _logger.Warn($"PLC连接中断，第{attempt}次重试...");
            await Task.Delay(attempt * 1000);  // 退避等待
        }
    }
}

2. 实时告警系统

// 设备阈值告警服务
public class AlertMonitorService : BackgroundService
{
    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
    {
        while (!stoppingToken.IsCancellationRequested)
        {
            var data = await _sensorService.GetCurrentValuesAsync();
            
            foreach (var item in data)
            {
                if (item.Value > item.UpperLimit)
                    _alertManager.TriggerAlarm(item.SensorId, AlarmType.OverThreshold);
                    
                if (DateTime.Now - item.LastUpdated > TimeSpan.FromMinutes(5))
                    _alertManager.TriggerAlarm(item.SensorId, AlarmType.Offline);
            }
            
            await Task.Delay(5000, stoppingToken);  // 5秒轮询
        }
    }
}

五、工业边缘计算实现

// 使用 ML.NET 实现设备异常预测
public class EquipmentFailurePredictor
{
    private readonly PredictionEngine<SensorHistory, FailurePrediction> _predictor;

    public EquipmentFailurePredictor(string modelPath)
    {
        var mlContext = new MLContext();
        var model = mlContext.Model.Load(modelPath, out _);
        _predictor = mlContext.Model.CreatePredictionEngine<SensorHistory, FailurePrediction>(model);
    }

    public FailurePrediction PredictFailure(SensorHistory data)
    {
        return _predictor.Predict(data);  // 执行边缘推理
    }
}

// 触发预测处理
if (_predictor.PredictFailure(sensorData).FailureProbability > 0.85)
{
    _plcService.SendCommand(deviceId, CommandType.SlowDown);
    _alertManager.TriggerAlarm(deviceId, AlarmType.PredictiveMaintenance);
}

六、工控开发最佳实践

1. ​​实时性保障

// 高优先级线程配置
var controlThread = new Thread(ControlLoop)
{
    Priority = ThreadPriority.Highest,  // 最高优先级
    IsBackground = false               // 关键线程禁止后台运行
};
controlThread.Start();

​​硬件资源约束方案

// 内存限制工作模式
var memoryLimit = 512 * 1024 * 1024;  // 512MB
using var manager = new MemoryManager(memoryLimit);

// 关键进程中自监控
if (Process.GetCurrentProcess().WorkingSet64 > memoryLimit)
{
    _logger.Error("内存超限，启动清理");
    _cacheService.ClearExpiredData();
}

​​版本升级策略

七、典型行业案例

​​汽车制造产线系统架构​​：

主要功能模块​​：

1. 冲压设备状态监控
2. 焊接机器人数据采集
3. 涂装环境参数控制
4. 总装线O质量分析
5. 整线设备效能分析

---

​​结论​​：
C# 在现代工控系统中承担着核心角色，通过：

• 成熟的工业协议栈支持 OPC UA/Modbus/EtherNetIP
• 强大的可视化框架 WPF
• .NET 6+ 的高性能运行时
• 完善的开发工具链 Visual Studio

某汽车焊装车间实际数据：

​​指标​​	传统方案	C#方案	提升幅度
设备故障响应	45分钟	<8分钟	82%
数据采集延迟	2.3秒	0.4秒	83%
OEE（设备综合效率）	76%	89%	17%
系统开发周期	9个月	5个月	44%

注意事项：

1. 工控软件需通过 IEC 61131-3 认证
2. 严格遵循 NIST SP 800-82 安全标准
3. 建议部署在 Windows IoT Enterprise 系统