解决办法：给el-select加  @change="$forceUpdate()" 强制刷新，就解决了

        <el-form-item label="抄表员" prop="meterName">
          <el-select
            v-model="form.meterName"
            placeholder="请选择抄表员"
            style="width: 600px"
            :disabled="disabledDetails"
            @change="$forceUpdate()"
          >
            <el-option
              v-for="item in meterUser"
              :key="item.userId"
              :label="item.userName"
              :value="item.userName"
            >
            </el-option>
          </el-select>